Temat: thermodynamic - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Solubility of a pharmacological intermediate drug Isatin in different solvents at various temperatures
Autorzy:: Baluja, S.
Bhalodia, R.
Bhatt, M.
Vekariya, N.
Gajera, R.
Powiązania:: https://bibliotekanauki.pl/articles/412531.pdf
Data publikacji:: 2013
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: Isatin
solubility
Thermodynamic parameters
Opis:: The solubility of isatin in different solvents was studied by a gravimetrical method from (298.15 to 318.15) K under atmospheric pressure and the solubility data were correlated against temperature. The solvents selected for the present study are: water, methanol, ethanol, 1-butanol, dichloromethane, dichloroethane, chloroform and carbon tetra chloride. Among chlorinated solvents, solubility is observed to be maximum in 1, 2-dichloroethane and minimum in dichloromethane whereas in alcohols, maximum solubility is observed in methanol. In water, solubility is found to be minimum. Further, some thermodynamic parameters such as Gibb’s energy (ΔGsol), heat of solution (ΔHsol) and entropy of solution (ΔSsol) have also been evaluated.
Źródło:: International Letters of Chemistry, Physics and Astronomy; 2013, 12; 36-46
2299-3843
Pojawia się w:: International Letters of Chemistry, Physics and Astronomy
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Thermodynamic Properties of Cu-S Solutions
Autorzy:: Kucharski, M.
Powiązania:: https://bibliotekanauki.pl/articles/353400.pdf
Data publikacji:: 2018
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: copper
sulphur
thermodynamic properties
Opis:: A new method for description of thermodynamic properties of Cu-S mixtures is put forward. The basic feature of this method is the assumption that the activity coefficient of sulphur dissolved in liquid copper is equal to 1 for infinite dilute solution (y_[S] = 1 for x_[S] = 0). In consequence the following relationships were established: 1. The equilibrium constant for the reaction of sulphur dissolution in liquid copper (0.5S₂ (g) = [S] _Cu ): [wzór]. 2. Non-temperature dependence of the activity coefficient of sulphur dissolved in the copper-reach liquid (Liquid I): lnγ_[S] =-18.25 · x_[S]. 3. The chemical potential of the sulphur dissolved in copper in infinite dilute solution: [wzór]. 4. Non-temperature dependence of the activity of sulphur in Cu-S sulphur-rich liquid (Liquid II) – Fig. 6. 5. Non-temperature dependence of the activity of copper in Cu-S sulphur-rich liquid (Liquid II) – Fig. 7. 6. The equilibrium constant for the reaction of sulphur removal from liquid copper ([S] _Cu + 2[O] _Cu = SO₂ (g)): [wzór].
Źródło:: Archives of Metallurgy and Materials; 2018, 63, 4; 1815-1820
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Gradient theory for the description of interfacial phenomena in flashing water flows
Autorzy:: Banaszkiewicz, M.
Badur, J.
Powiązania:: https://bibliotekanauki.pl/articles/1953939.pdf
Data publikacji:: 2000
Wydawca:: Politechnika Gdańska
Tematy:: capillarity
flashing flow
thermodynamic nonequilibrium
Opis:: The present work concerns the description of phenomena taking place within interfacial regions during a flow of water, which is accompanied by heterogeneous flashing. The main aim of the work is to present a unified approach to first order phase transitions with the inclusion of capillary effects and to built on this basis a mathematical model describing nonequilibrium two-phase flows, in which the properties of the mixture include capillary components. The analysis of the problem was started with a discussion of physical aspects of flashing, which are the contents of Chapter 2. On the basis of the experimental data analysis a physical model of the phenomenon was formulated. In Chapter 3 a gradient description of first order heterogeneous phase transitions was given. The analysis was begun with a discussion of the properties and structure of interfacial areas. On the basis of the analysis constitutive equations for reversible stress tensor and free energy of a two-phase system treated as a homogeneous medium were formulated. The constitutive equations include capillary components modelled by means of the dryness fraction gradients and resulting from the nonuniformity of the system caused by the existence of two phases and interfacial surfaces. On the basis of the proposed theory a homogeneous model of two-phase flow with capillary effects was derived, which is a subject of Chapter 4. Taking into consideration the assumptions of the homogeneous model, one-dimensional balance equations for mass, momentum and energy of the mixture and mass of vapour were derived. A constitutive equation for the source term appearing in the last equation was obtained on the basis of the theory of internal parameters with the usage of the proposed form of free energy including a gradient term known from the second gradient theory. The remaining constitutive equations for the density of the two-phase system, wall shearing stresses and capillary pressure were also given. The proposed mathematical model was investigated from the point of view of wave properties, which were discussed in Chapter 5. The analysis of small disturbations was conducted, as a result of which a dispersion equation was obtained giving a relation between the velocity of disturbations, attenuation coefficient and frequency. This dispersive model was then applied for the prediction of critical mass flux in a channel flow using PIF method. On the basis of the comparison of the model predictions with experimental measurements a reasonably good agreement was found. In Chapter 6 the results of numerical calculations of flashing flow in channel were presented. Since the proposed mathematical model contains several phenomenological coefficients, a parametric analysis was performed in order to determine their value and the influence on solutions. For the sake of the analysis the classical benchmark experiment known as the Moby Dick was used. After fitting the solution of the model into the experimental measurements new calculations for other runs and other experiments were carried out. As a result of the analysis a good agreement of the model with reality was found, as well as its usefulness for the calculations of pressure and void fraction distributions in channels and for the determination of mass flow rate of two-phase systems. It constitutes a confirmation of the correctness of the proposed model as well as the theory on the basis of which it was built.
Źródło:: TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2000, 4, 2; 213-290
1428-6394
Pojawia się w:: TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Integrated approach of environmental issues in industrial complex treated as complicated operated machine
Autorzy:: Kamiński, A.
Powiązania:: https://bibliotekanauki.pl/articles/246034.pdf
Data publikacji:: 2015
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: integrated environmental approach
thermodynamic machine
Opis:: Refining, petrochemical and energy industry are examples of influence on all environment components. Uncontrolled imposing new stricter burdens and legal requirements may cause the lack of expected results in reducing their impact on the environment. Moreover, effects may be counterproductive. Simultaneously, companies have to balance between legislative challenges, social expectations and technical possibilities, paying special attention on Corporate Social Responsibility (CSR), sustainability and biodiversity. During the Fifth Refinery Forum in Brussels, representatives of the European Commission admitted that legislation laid down within the European Union in the years 2000-2012 lowered the competitiveness of European refining industry. This status is proven by the analysis of refining industry prepared by The Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs, and Joint Research Centre [1]. Weakening demand for fuels, lack of opportunities for increasing the capacity of European refineries (permanent shutdowns) and shale revolution cause a number of challenges including environmental. Therefore, it is necessary to take into account all factors mentioned above, and an integrated approach to environmental and climate protection in the face of changing legal regulations becomes crucial. This article proposes a new integrated, model approach to all issues connected with environmental protection in refining, petrochemical and energy complexes. In simple words, such complexes require maintenance shutdowns, repairs, overhauls. In addition, in the process various forms of energy is used and converted, so we can talk about the “exploitation of high thermodynamic machine”.
Źródło:: Journal of KONES; 2015, 22, 2; 110-114
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Thermodynamic Description of Ternary Fe-B-X Systems. Part 7: Fe-B-C
Autorzy:: Miettinen, J.
Visuri, V.-V.
Fabritius, T.
Vassilev, G.
Powiązania:: https://bibliotekanauki.pl/articles/352609.pdf
Data publikacji:: 2020
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: phase diagrams
thermodynamic modelling
thermodynamic database
Fe-B-X systems
Fe-B-C system
Opis:: Thermodynamic description of the Fe-B-C system in its iron-rich corner is developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, Si, Ti, V, C) database. The thermodynamic parameters of the binary sub-systems, Fe-B, Fe-C and B-C, are taken from earlier assessments modifying the B-C description. The parameters of the Fe-B-C system are optimized in this study using experimental thermodynamic and phase equilibrium data from the literature. Liquid, beta-rhombo-B and graphite phases are described using the substitutional solution model, while the ferrite (bcc), the austenite (fcc), the cementite (M₃C) and the M₂₃C₆ phases are described with the sublattice model and the borides, Fe₂B, FeB and B₄C, are treated as stoichiometric phases. A good correlation was obtained between the calculated and the experimental thermodynamic and phase equilibrium data. The description is recommended to be used at the composition region of wt% C + wt% B < 15 and at temperatures below 2700°C.
Źródło:: Archives of Metallurgy and Materials; 2020, 65, 2; 923-933
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: Właściwości termodynamiczne minerałów z szeregu piromorfit - mimetyt
Autorzy:: Flis, J.
Powiązania:: https://bibliotekanauki.pl/articles/344088.pdf
Data publikacji:: 2007
Wydawca:: nakł. Maciej Pawlikowski
Tematy:: minerały
właściwości termodynamiczne
minerals
thermodynamic properties
Źródło:: Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering; 2007, T. 4 spec. ed. [2]; 1-4
1689-6742
Pojawia się w:: Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Thermodynamic fundamentals for production of electric power in hierarchical j-cycle system
Autorzy:: Bartnik, R.
Powiązania:: https://bibliotekanauki.pl/articles/175297.pdf
Data publikacji:: 2014
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: thermodynamic fundamentals
hierarchical j -cycle systems
Opis:: This paper presents thermodynamic fundamentals for the generation of power in the hierarchical j -cycle systems.
Źródło:: Transactions of the Institute of Fluid-Flow Machinery; 2014, 126; 141-151
0079-3205
Pojawia się w:: Transactions of the Institute of Fluid-Flow Machinery
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Thermodynamic analysis of the influence of potassium on the thermal behavior of kaolin raw material
Autorzy:: Hernández-Chávez, Macaria
Vargas-Ramírez, Marissa
Herrera-González, Ana Maria
García-Serrano, Jesús
Cruz-Ramírez, Alejandro
Romero-Serrano, José Antonio
Sánchez-Alvarado, Ricardo Gerardo
Powiązania:: https://bibliotekanauki.pl/articles/1448343.pdf
Data publikacji:: 2021
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: kaolin
thermal treatment
thermodynamic analysis
viscosity
Opis:: The mineralogy and thermal properties of two kaolin clay samples from Agua Blanca (Hidalgo-México) were determined by XRD, SEM-EDS, TGA-DSC techniques. Kaolin clay A contains a higher $Al_2O_3$ and lower impurities $(K_2O, TiO_2, Fe_2O_3)$ amount than kaolin clay B, while the SiO2 amount is similar for both kaolin clays. A theoretical approach was carried out by a thermodynamic analysis considering the chemical composition of both kaolin clay samples with the FactSage 7.3 software. Stability phase diagrams were obtained to different K2O content from 0.1 to 3 wt % and temperatures in the range from 600 to 1600°C based on the chemical composition of the kaolin clay samples. The main mineralogical compounds predicted are andalusite $(Al_2O_3•SiO_2)$, K-Potash feldspar $(K_2O•Al_2O_3•6SiO_2)$, and the $SiO_2$ polymorphs (quartz, tridymite, and cristobalite) with small amounts of ferric-pseudobrookite $(Fe_2O_5Ti)$, and rutile $(TiO_2)$. As $K_2O$ content is increased, the amounts of mullite and tridymite decrease meanwhile the potash feld spar is increased at high temperatures. A liquid phase is formed at around 1350 and 1400°C for the kaolin clay samples A and B, respectively. The viscosity of the melt is increased for the evaluated $K_2O$ additions to 1400, 1500, and 1600°C.
Źródło:: Physicochemical Problems of Mineral Processing; 2021, 57, 1; 39-52
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:: Thermodynamic Description of Ternary Fe-B-X Systems. Part 4: Fe-B-V
Autorzy:: Miettinen, J.
Visuri, V.-V.
Fabritius, T.
Milcheva, N.
Vassilev, G.
Powiązania:: https://bibliotekanauki.pl/articles/355188.pdf
Data publikacji:: 2019
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: phase diagrams
thermodynamic modelling
Fe-based systems
Fe-B-X systems thermodynamic database
Fe-B-V system
Opis:: Thermodynamic descriptions of the ternary Fe-B-V system and its binary sub-system B-V, are developed using experimental thermodynamic and phase equilibrium data from the literature. The thermodynamic parameters of the other binaries, Fe-V and Fe-B, are taken from earlier assessments slightly modifying the Fe-V description. The work is in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database. The solution phases are described using substitutional solution model. The borides are treated as stoichiometric or semistoichiometric phases and described with two-sublattice models.
Źródło:: Archives of Metallurgy and Materials; 2019, 64, 2; 451-456
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Numerical Modelling of Phase Diagrams of Copper Alloys for Optimization of Semi-Solid Forming
Autorzy:: Madetko, Arkadiusz
Sołek, Krzysztof
Drożdż, Paweł
Powiązania:: https://bibliotekanauki.pl/articles/28099580.pdf
Data publikacji:: 2023
Wydawca:: Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:: thixoforming
thermodynamic calculations
copper alloys
phase diagram
Opis:: Processing of metal alloys in semi-solid state is a way of producing many near net-shape parts and nowadays is commercially successful. Particular behaviour of alloys in the partially liquid state, having non-dendritic microstructure, is a base for thixoforming processing. Processing materials in the semi-solid state concerns alloys with relatively wide solidification range. Thermodynamic modelling can be used as a one of a potential tools that allow to identify alloys with proper temperature range. It means that the key feature of alloys suitable for thixoforming is a widely enough melting range, allowing for precise control of material temperature. The data gathered from thermodynamics calculations can also pay off in the industrial thixoforming processes design. The goal of this paper is to identify copper alloys which can be successfully shaped in the semi-solid state. Apart to thermodynamic calculations, the observations on high temperature microscope was carried out. During experiments the solidus, liquidus and also deformation temperatures can be determined. An experimental work allows confirming results obtained within the confines of thermodynamic calculations and firstly to determine the deformation temperatures which are the optimal for shaping processes. The basic achievement of this work is an identification of copper alloy groups possible for shaping in the semi-solid state. At the first part of the paper, the basic criteria of suitable alloys were described. Next, both the solid fraction curves for copper alloys with different alloying elements using ProCAST software and the phase diagrams were determined to identify the solidification temperature ranges of these alloys. In the second part of these paper, the identification of the deformation temperatures was carried out with use of high temperature microscope observation.
Źródło:: Archives of Metallurgy and Materials; 2023, 68, 2; 689--696
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 11.

Tytuł:: Właściwości termodynamiczne składników mieszanin oddechowych
Therodynamic properties of breathing mixtures components
Autorzy:: Majchrzycka, A.
Powiązania:: https://bibliotekanauki.pl/articles/366126.pdf
Data publikacji:: 2011
Wydawca:: Polskie Towarzystwo Medycyny i Techniki Hiperbarycznej
Tematy:: właściwości termodynamiczne
mieszaniny oddechowe
thermodynamic properties gases
Opis:: W pracy przedstawiono równania regresji, opisujące właściwości termodynamiczne składników czynników oddechowych: gazów obojętnych, zanieczyszczeń metabolicznych (ditlenek węgla, przegrzana para wodna) oraz dodatku gazowego - sześciofluorku siarki, poprawiającego właściwości użytkowe mieszaniny oddechowej.
The paper reports regression functions describing thermal properties of gas components of breathing mixtures, metabolic gaseous contaminants (carbon dioxide, superheated water vapour) and gaseous additive sulphur hexafluoride improving properties of breathing mixture.
Źródło:: Polish Hyperbaric Research; 2011, 4(37); 7-20
1734-7009
2084-0535
Pojawia się w:: Polish Hyperbaric Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 12.

Tytuł:: STABILITY STUDIES OF CEFTIOFUR SODIUM IN AQUEOUS SOLUTIONS AND IN THE SOLID PHASE
Autorzy:: Dołhań, Agnieszka
Sobczak, Agnieszka
Muszalska, Izabela
Medenecka, Beata
Garbacki, Piotr
Tomczak, Szymon
Jelińska, Anna
Powiązania:: https://bibliotekanauki.pl/articles/895368.pdf
Data publikacji:: 2018-12-31
Wydawca:: Polskie Towarzystwo Farmaceutyczne
Tematy:: stability
kinetic parameters
thermodynamic parameters
solid phase
Opis:: Ceftiofur sodium (CFT), a third-generation cephalosporin for parenteral use, is commonly used in veterinary medicine against aerobic Gram-positive and Gram-negative bacteria as well as certain anaerobes. Its broad spectrum of activity and resistance to beta-lactamases result from the presence of methoxyimino and aminothiazole moieties at C-7 in the cephalosporin structure. The aim of this study was a comprehensive evaluation of the stability of CFT in the solid phase and in aqueous solutions. A fast and sensitive HPLC isocratic method was used for the determination of CFT degradation in the solid phase and in aqueous solutions. CFT degradation occurred according to a first-order reaction depending on the substrate concentration. The kinetic and thermodynamic parameters of CFT degradation in the solid phase were calculated. General acid-base hydrolysis of CFT was not observed in the solutions of hydrochloric acid, sodium hydroxide, phosphate (pH 5.84 – 7.25), acetate (pH 3.65 – 5.48) and borate (pH 7.49 – 10.07) buffers. CFT was the most stable in the pH range 2 – 6. The susceptibility of CFT to degradation under the influence of stress factors (pH, temperature, buffer components concentration, relative air humidity) should be considered in terms of storage conditions and the preparation of the product for administration.
Źródło:: Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 6; 1279-1286
0001-6837
2353-5288
Pojawia się w:: Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 13.

Tytuł:: Optimization of idealized ORC in domestic combined heat and power generation
Autorzy:: Rybiński, W.
Mikielewicz, J.
Powiązania:: https://bibliotekanauki.pl/articles/240921.pdf
Data publikacji:: 2013
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: ORC
CHP
thermodynamic optimization
endoreversible
optymalizacja termodynamiczna
Opis:: Organic Rankine cycle (ORC) is used, amongst the others, in geothermal facilities, in waste heat recovery or in domestic combined heat and power (CHP) generation. The paper presents optimization of an idealized ORC equivalent of the Carnot cycle with non-zero temperature difference in heat exchangers and with energy dissipation caused by the viscous fluid flow. In this analysis the amount of heat outgoing from the ORC is given. Such a case corresponds to the application of an ORC in domestic CHP. This assumption is different from the most of ORC models where the incoming amount of heat is given.
Źródło:: Archives of Thermodynamics; 2013, 34, 3; 137-146
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 14.

Tytuł:: Thermodynamic Description of Ternary Fe-B-X Systems. Part 9: Fe-B-Cu
Autorzy:: Miettinen, Jyrki
Visuri, Ville-Valtteri
Fabritius, Timo
Powiązania:: https://bibliotekanauki.pl/articles/2049545.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: phase diagrams
thermodynamic modelling
thermodynamic database
Fe-based systems
Fe-B-X systems
Fe-B-Cu system
Opis:: Thermodynamic descriptions of the ternary Fe-B-Cu system and its binary sub-system B-Cu aredeveloped in the context of a new Fe-B-X (X = Cr, Cu, Mn, Mo, Ni, Si, Ti, V, C) database. The thermodynamic parameters of the other binary sub-systems (Fe-B and Fe-Cu) are taken from earlier assessments. Experimental thermodynamic and phase equilibrium data available in the literature have been used for the optimization of the Fe-B-Cu and B-Cu systems’ thermodynamic parameters. The solution phases are described using a substitutional solution model and the compounds (two borides of the Fe-B system) are treated as stoichiometric phases. A good agreement was obtained between the calculated and the experimental thermodynamic and phase equilibrium data.
Źródło:: Archives of Metallurgy and Materials; 2021, 66, 1; 297-304
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 15.

Tytuł:: Thermodynamic Description of Ternary Fe-B-X Systems. Part 5: Fe-B-Si
Autorzy:: Miettinen, J.
Visuri, V.-V.
Fabritius, T.
Milcheva, N.
Vassilev, G.
Powiązania:: https://bibliotekanauki.pl/articles/355656.pdf
Data publikacji:: 2019
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: phase diagrams
thermodynamic modeling
Fe-based systems
Fe-B-X systems thermodynamic database
Fe-B-Si system
Opis:: Thermodynamic descriptions of the ternary Fe-B-Si system and its binary sub-system, B-Si, are developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database. The thermodynamic parameters of the other binary sub-systems, Fe-Si and Fe-B, are taken from earlier assessments. Experimental thermodynamic and phase equilibrium data available in the literature has been used for the optimization of the thermodynamic parameters of the Fe-B-Si and B-Si systems. The solution phases are described using substitutional solution model and the compounds (silicides and borides) are treated as stoichiometric phases. The calculated and experimental thermodynamic and phase equilibrium data were found to be in good agreement.
Źródło:: Archives of Metallurgy and Materials; 2019, 64, 4; 1239-1248
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 16.

Tytuł:: Thermodynamic Description of Ternary Fe-B-X Systems. Part 6: Fe-B-Ti
Autorzy:: Miettinen, J.
Visuri, V.-V.
Fabritius, T.
Milcheva, N.
Vassilev, G.
Powiązania:: https://bibliotekanauki.pl/articles/356115.pdf
Data publikacji:: 2019
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: phase diagrams
thermodynamic modeling
Fe-based systems
Fe-B-X systems thermodynamic database
Fe-B-Ti system
Opis:: Thermodynamic optimizations of the ternary Fe-B-Ti system and its binary sub-system, B-Ti are presented. The thermodynamic descriptions of the other binaries, Fe-Ti and Fe-B, are taken from the earlier studies slightly modifying the Fe-Ti system assessment. The adjustable parameters of the Fe-B-Ti and B-Ti systems are optimized in this study using the experimental thermodynamic and the phase equilibrium data from the literature. The solution phases of the system are described using the substitutional solution model and the compounds (including borides) are treated as stoichiometric phases. The results show a good correlation between the calculated and measured thermodynamic and phase equilibrium data.
Źródło:: Archives of Metallurgy and Materials; 2019, 64, 4; 1249-1255
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 17.

Tytuł:: Thermodynamic Analysis of Precipitation Process of Complex Carbonitride TixV1-xCyN1-y in HSLA-Type Steel
Autorzy:: Wojtacha, Anna
Opiela, Marek
Powiązania:: https://bibliotekanauki.pl/articles/2201794.pdf
Data publikacji:: 2022
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:: carbonitride
thermodynamic model
HSLA-type steel
microstructure
Opis:: The paper presents a detailed analysis of the MX-type interstitial phase precipitation process and a thermodynamic analysis of the TixV1-xCyN1-y carbonitride precipitation in austenite. The subject of research analysis was the newly developed HSLA-type steel containing 0.175% C, 1.02% Si, 1.87% Mn, 0.0064% N, 0.22% Mo, and microadditions 0.022% V and 0.031% Ti. Analysis of the process of precipitation of MX interstitial phases under thermodynamic equilibrium conditions proved that the first phase that precipitates in the austenite of the tested steel is TiN-type nitride. The onset temperature of this phase was 1450°C. Subsequently, carbides of the TiC-type, VN-type nitrides and VC-type carbides, for which the precipitation onset temperatures were 1180°C, 870°C and 775°C will be released, respectively. The analysis of the precipitation process of the complex carbonitride in austenite under thermodynamic equilibrium conditions was based on the Hillert and Staffansson model, developed by Adrian, with the use of the CarbNit computer program. The beginning of carbonitride precipitation with the stoichiometric composition Ti0.985V0.015C0.073N0.927 occurred at the temperature of 1394°C. At 850°C practically all of the Ti is bound in the carbonitride of the stoichiometric composition Ti0.883V0.117C0.378N0.622. At the same temperature, a significant part of microaddition V will be dissolved in austenite, which means that vanadium will have a lesser effect on the formation of a fine-grained austenite structure, but more strongly on the precipitation hardening of steel by the dispersion VN and V particles (C,N) released during the cooling of the products.
Źródło:: Advances in Science and Technology. Research Journal; 2022, 16, 4; 64--73
2299-8624
Pojawia się w:: Advances in Science and Technology. Research Journal
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 18.

Tytuł:: Thermodynamic Analysis of the Graphite Flake Formation of Low Manganese and Sulfur Gray Cast Iron
Autorzy:: Reyes-Castellanos, G.
Cruz-Ramírez, A.
Colin-García, E.
Gutiérrez-Pérez, V. H.
Powiązania:: https://bibliotekanauki.pl/articles/2049436.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: gray iron
inoculation
cell count
thermodynamic analysis
Opis:: Low manganese and sulfur gray irons were produced by adding inoculant base Fe-Si with small amounts of Al and Ca in the ladle. The effect of the cast thickness, inoculant amount and shakeout time of the green sand molds were studied on the graphite flake formation by microscopically techniques. A thermodynamic analysis was carried out for the cast iron produced with the FactSage 7.2 software. Stability phase diagrams were obtained for both gray cast irons to different manganese (0.1 to 0.9 wt.%) and sulfur (0.01 to 0.12 wt.%) amounts to 1150°C. It was shown that lower amounts of manganese and sulfur allow forming the 3Al2O3·2SiO2, Al2O3, and ZrO2 solid compounds. The thermodynamic results match with those obtained by SEM-EDS. It is possible to form MnS particles in the liquid phase when the solubility product (%Mn) × (%S) equals 0.042 and 0.039 for heats A and B, respectively.
Źródło:: Archives of Metallurgy and Materials; 2021, 66, 1; 249-258
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 19.

Tytuł:: Constructional changes of pneumopercussion machines for improving their efficiency
Autorzy:: Antonchik, Volodymyr
Zabolotnyi, Kostiantyn
Hankevich, Valentyn
Maltseva, Vira
Kuts, Oleksandra
Dyczko, Artur
Powiązania:: https://bibliotekanauki.pl/articles/27324346.pdf
Data publikacji:: 2022
Wydawca:: Instytut Techniki Górniczej KOMAG
Tematy:: pneumopercussion machines
thermodynamic processes
hammer
compressed air
Opis:: Pneumopercussion machines (pneumatic impact machines) are widely used in all areas of human activity. Also, they are widely used in the mining industry. Unfortunately, their operation is characterized by a low efficiency of compressed air energy usage. In some cases, this level of efficiency is calculated as 15-20%. Such a situation increases the cost of drilling operations significantly. In this article, due to an implementation of a new construction of the equipment, the efficiency of the pneumopercussion machines was increased. This problem is solved by combining the most effective thermodynamic processes of compressed air in the working chambers of machines. Also, a new technical solution for the construction of pneumopercussion machines is suggested by the Authors. The proposed new design is realized by a combination of the most effective thermodynamic processes in the chambers of pneumatic impact machines. A new pneumatic hammer is presented, which allows to reduce compressed air consumption twice during an operation on the surface (in comparison with hammers available on the market). The operation of pneumopercussion machines and the method of calculating geometric parameters are described. The economic performance of the equipment confirms the correctness of the proposed technological solutions.
Źródło:: Mining Machines; 2022, 40, 4; 206--215
2719-3306
Pojawia się w:: Mining Machines
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 20.

Tytuł:: Elastic Anisotropic and Thermodynamic Properties of Two BC₇ Phases
Autorzy:: Xing, Mengjiang
Li, Binhua
Yu, Zhengtao
Chen, Qi
Powiązania:: https://bibliotekanauki.pl/articles/1032568.pdf
Data publikacji:: 2017-10
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: ab initio
elastic properties
anisotropic properties
thermodynamic properties
Opis:: The structural, elastic, anisotropic, and thermodynamic properties of P3m1-BC₇ and Pmm2-BC₇ have been studied in this paper utilizing first-principles calculations. In comparison with the elastic properties of Pmm2-BC₇, P3m1-BC₇ exhibits slightly higher values in bulk modulus and B/G, with similar values in shear modulus, the Young modulus, and the Poisson ratio. The calculated Pugh modulus ratio (B/G) and the Poisson ratio demonstrates P3m1-BC₇ from brittle to ductile at 93.60 and 93.73 GPa, respectively. Calculations of shear anisotropic factor, universal elastic anisotropy index, shear modulus, the Young modulus, and the Poisson ratio for BC₇ then demonstrate that Pmm2-BC₇ exhibits a larger elastic anisotropy than P3m1-BC₇. Quasi-harmonic Debye model is finally applied to investigate the Debye temperature, the coefficient of thermal expansion, heat capacity and Grüneisen parameter of Pmm2-BC₇ and P3m1-BC₇.
Źródło:: Acta Physica Polonica A; 2017, 132, 4; 1340-1346
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 21.

Tytuł:: Heat exchangers technology and applications in heat exchanger engineering
Autorzy:: Omer, Abdeen Mustafa
Powiązania:: https://bibliotekanauki.pl/articles/1030671.pdf
Data publikacji:: 2020
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: Absorption cycles
environment
heat pumps
refrigeration cycles
thermodynamic
Opis:: Over the years, all parts of a commercial refrigerator, such as the compressor, heat exchangers, refrigerant, and packaging, have been improved considerably due to the extensive research and development efforts carried out by academia and industry. However, the achieved and anticipated improvement in conventional refrigeration technology are incremental since this technology is already nearing its fundamentals limit of energy efficiency is described is ‘magnetic refrigeration’ which is an evolving cooling technology. The word ‘green’ designates more than a colour. It is a way of life, one that is becoming more and more common throughout the world. An interesting topic on ‘sustainable technologies for a greener world’ details about what each technology is and how it achieves green goals. Recently, conventional chillers using absorption technology consume energy for hot water generator but absorption chillers carry no energy saving. With the aim of providing a single point solution for this dual purpose application, a product is launched but can provide simultaneous chilling and heating using its vapour absorption technology with 40% saving in heating energy. Using energy efficiency and managing customer energy use has become an integral and valuable exercise. The reason for this is green technology helps to sustain life on earth. This not only applies to humans but to plants, animals and the rest of the ecosystem. Energy prices and consumption will always be on an upward trajectory. In fact, energy costs have steadily risen over last decade and are expected to carry on doing so as consumption grows. Refrigerants such as hydrochlorofluorocarbons (HCFCs) are present in the ground source heat pump (GSHP) systems and can pose a threat to the environment through being toxic, flammable or having a high global warming potential.
Źródło:: World Scientific News; 2020, 139, 2; 76-101
2392-2192
Pojawia się w:: World Scientific News
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 22.

Tytuł:: Adsorption and adsorption isotherm: application to corrosion inhibition studies of mild steel in 2 M HCl
Autorzy:: Abeng, F. E.
Idim, V. D.
Obono, O. E.
Magu, T. O.
Powiązania:: https://bibliotekanauki.pl/articles/1178372.pdf
Data publikacji:: 2017
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: Adsorption isotherm
inhibition mechanism
mild steel
thermodynamic parameters
Opis:: Ethanollic extract of Phyllanthus amarus (EEPA) was tested as corrosion inhibitor for mild steel in 2 M HCl solution using gravimetric and gasometric methods at 303, 313, 323 K and 333 K. The results revealed that the corrosion rate increases with temperature and time. Addition of the concentration of ethanollic extract of Phyllanthus amarus to the corroding environment lowered the corrosion rate of mild steel and increased inhibition efficiency (IE %) of ethanollic extract. Inhibition efficiency was found to decreased with temperature. Fitting of the experimental data to the Arrhenius and Transition state equations revealed that the Organic constituents of the extract were physically adsorbed on the corroding surface of the steel and adsorption of ethanollic extract of Phyllanthus amarus (EEPA) on mild steel surface was found to obey the Langmuir adsorption isotherm and Freundlich adsorption isotherm and sign of the Gibb’s fee energy of the adsorption obtained suggested that inhibitor molecules have been spontaneously adsorbed onto the mild steel surface. Positive values obtained for enthalpy change indicated that the adsorption of inhibitor is endothermic.
Źródło:: World Scientific News; 2017, 77, 2; 298-313
2392-2192
Pojawia się w:: World Scientific News
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 23.

Tytuł:: Stanowisko laboratoryjne do wyznaczania parametrów termodynamicznych sprężarki tłokowej
Laboratory stand for determining piston compressor thermodynamic parameters
Autorzy:: Gawędzki, W.
Dziekan, A.
Hajto, P.
Powiązania:: https://bibliotekanauki.pl/articles/157042.pdf
Data publikacji:: 2008
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:: sprężarka tłokowa
parametry termodynamiczne
cykl termodynamiczny
pomiar szybkozmiennej temperatury
piston compressor
thermodynamic parameters
thermodynamic cycle
fast-variable temperature measurement
Opis:: W artykule omówiono stanowisko laboratoryjne do automatycznego wyznaczania parametrów i charakterystyk termodynamicznych sprężarki tłokowej, które może być również wykorzystane do badania innych typów obiektów, w których zachodzą przemiany termodynamiczne względnie dla celów dydaktycznych. Omówiono opracowane metody wyznaczania parametrów termodynamicznych, zastosowane układy kondycjonowania sygnałów oraz sposoby kalibracji torów pomiarowych. Opracowany system umożliwia pomiar chwilowych wartości temperatury, objętości czynnej w cylindrze sprężarki, ciśnień oraz przepływu powietrza, a także wyznaczenie cyklu termodynamicznego (p=f(V)) oraz wyznaczenie bilansu energetycznego i określenie sprawności sprężarki.
The paper presents the laboratory stand for automatic measurements of thermodynamic parameters and characteristics of a piston compressor. The stand can also be used for investigations of thermodynamic parameters of other systems as well as for didactics. The methods used for determining the thermodynamic parameters and calibrating the measurement equipment are discussed. The system enables measurements of the instantaneous values of temperature, active volume of a compressor cylinder, pressure and air flow velocity. The thermodynamic cycle (p=f(V)), energy balance and compressor efficiency factor can also be determined.
Źródło:: Pomiary Automatyka Kontrola; 2008, R. 54, nr 12, 12; 883-886
0032-4140
Pojawia się w:: Pomiary Automatyka Kontrola
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 24.

Tytuł:: Acoustical studies of binary liquid mixtures of p-chlorotoluene in benzene at different temperatures
Autorzy:: Kumar, G. P.
Babu, Ch. P.
Samatha, K
Jyosthna, A. N.
Showrilu, K.
Powiązania:: https://bibliotekanauki.pl/articles/412275.pdf
Data publikacji:: 2014
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: ultrasonic velocity
thermodynamic parameters
p-chlorotoluene
molecular interactions
Opis:: Ultrasonic velocities (U), densities (ρ), and coefficient of viscosities (η) are measured for binary mixtures containing (i) p-chlorotoluene and (ii) benzene at 303.15 K, 308.15 K, 313.15 K and 318.15 K to understand the molecular interaction. Various acoustical parameters such as adiabatic compressibility (βad), free length (Lf), acoustic impedance (Z), free volume (Vf), molar volume (Vm), Rao’s constant (R), Wada’s constant (W) and internal pressure (πi), are calculated from the measured values of U, ρ, and η. The trend in acoustical parameters also substantiates to asses strong molecular interactions.
Źródło:: International Letters of Chemistry, Physics and Astronomy; 2014, 10; 25-37
2299-3843
Pojawia się w:: International Letters of Chemistry, Physics and Astronomy
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 25.

Tytuł:: Thermal analysis of car air cooler
Autorzy:: Trzebiński, D.
Szczygieł, I.
Powiązania:: https://bibliotekanauki.pl/articles/242031.pdf
Data publikacji:: 2011
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: car air conditioning
refrigerant
thermal comfort
thermodynamic cycle
Opis:: People more and more time spend in vehicles (cars, trains, planes, buses or subway). This is the reason why the thermal comfort has more and more paid attention. In one hand people try to make comfort (in each situation) whatever they are at home, office or in car. In the other hand the thermal conditions in the cabin of vehicles directly influences on the driver's and passengers safety. The investigations presented in this paper are the part of larger project, which assumes complex modelling of thermal state of car interior. First part assumes creation of CFD model of car interior. Second part is thermodynamic modelling of air cooling unit in order to estimate the influence of basic cabin parameters on the A/C unit COP, power consumption of the unit and fuel consumption of the vehicle. In the paper thermodynamic analysis of car air cooler is presented. Typical refrigerator cycles are studied: one with uncontrolled orifice and non controlled compressor, second with thermostatic controlled expansion valve and externally controlled compressor. The influence of refrigerant charge and the inlet air temperature on the coefficient of performance, exergy efficiency, heat flux and temperature in evaporator and compressor net power were investigated. The impact of improper refrigerant charge on the performance of A/C systems was also checked.
Źródło:: Journal of KONES; 2011, 18, 2; 439-446
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 26.

Tytuł:: Synthesis and evaluation of thermodynamic solubility of triazolo quinolone class derivatives in various solvents at 298.15-328.15 K
Autorzy:: Baluja, Shipra
Pithiya, Mona
Lava, Divyata
Powiązania:: https://bibliotekanauki.pl/articles/1031268.pdf
Data publikacji:: 2021
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: Triazolo quinolone
alcohols
ethyl acetate
solubility
thermodynamic parameters
Opis:: The solubility of triazolo quinolone class derivatives in methanol, ethanol, n-propanol, n-butanol and ethyl acetate was measured using a gravimetrical method at temperature ranging from 298.15 K to 328.15 K. The results of these measurements were correlated with semi empirical equations. Some thermodynamic parameters such as dissolution enthalpy, Gibb’s free energy and entropy of mixing have also been calculated.
Źródło:: World Scientific News; 2021, 151; 16-30
2392-2192
Pojawia się w:: World Scientific News
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 27.

Tytuł:: First Principle Investigations on Electronic, Magnetic, Thermodynamic, and Transport Properties of TlGdX₂ (X = S, Se, Te)
Autorzy:: Gautam, R.
Kumar, A.
Singh, R.
Powiązania:: https://bibliotekanauki.pl/articles/1032602.pdf
Data publikacji:: 2017-10
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: semiconductors
electronic structure
magnetic properties and thermodynamic properties
Opis:: In the present research paper, we investigated spin polarized electronic, magnetic, thermodynamic, and transport properties of thallium gadolinium dichalcogenides TlGdX₂ (X = S, Se, Te) using density functional theory. Electronic structure reveals that all the three compounds are wide band gap semiconductors which are beneficial for good thermoelectric performance. Calculated magnetic moment of TlGdX₂ is found to be in good agreement with available experimental values and mainly dominant by Gd³⁺ ions. Semiclassical Boltzmann transport theory has been used to calculate the Seebeck coefficient and electrical conductivity for the proposed dichalcogenides. Calculated values of the Seebeck coefficient and electrical conductivity are found to be consistent with available experimental values in literature. Thermodynamic properties of TlGdX₂ have also been estimated for the first time and explained on the basic facts.
Źródło:: Acta Physica Polonica A; 2017, 132, 4; 1371-1378
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 28.

Tytuł:: Investigation into the effect of bore/stroke ratio on a single cylinder two stroke opposed piston engin
Autorzy:: Alqahtani, A. M.
Wyszynski, M. L.
Mazuro, P.
Powiązania:: https://bibliotekanauki.pl/articles/245226.pdf
Data publikacji:: 2016
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: opposed-piston
two-stroke
AVL Boost
thermodynamic modelling
Opis:: Opposed-piston (OP) engine’s promising fuel efficiency has attracted the interest of automotive industry in the recent years. The opposed-piston two-stroke (OP2S) engine technology heightens this fuel efficiency benefit and offers advances in structure, power density and thermal efficiency whilst sustaining its lower cost and weight. Today thermodynamic modelling remains an indispensable and cost effective route in the development and optimisation of internal combustion engines (ICEs). To achieve this goal, the OP2S engine is simulated and validated against experimental results in AVL Boost™, which is hailed as one of the most reliable and advanced engine simulation tools. Detailed analyses of the piston dynamics, heat release, scavenging and heat transfers are highlighted in discrete sections of this paper. Having compared distinct heat release models, the Wiebe 2-Zone model emerged efficacious in replicating the heat release characteristics of the PAMAR™ engine. In comparing the numerical and experimental results, the simulation revealed minimal differences in peak pressure, peak temperature and maximum pressure raise rate, under ±2.5% differences for indicated power, IMEP, indicated thermal efficiency (ITE) and ISFC. Subsequently, confidence taken from the validated numerical model is then deployed to investigate the effect of stroke-to-bore (S/B) ratio on OP2S performance. Three combinations of S/B ratios (0.5, 1.25, and 1.69) with identical swept volume are analysed in this study. Utilisation of the validated model ensured the standardisation of intake, exhaust and the combustion systems in order to isolate the effects of S/B ratio. Results indicate that heat losses decrease with increasing S/B ratio because of the reduced surface area-to-volume in the cylinder. Consequently, an improvement in ITE and mechanical efficiency is observed with reduced ISFC for higher S/B ratios. A tendency of upsurge in combustion efficiency is also evident for higher S/B ratio due to reduced heat transfer near minimum volume of the combustion chamber.
Źródło:: Journal of KONES; 2016, 23, 2; 9-16
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 29.

Tytuł:: Wpływ dodatku tworzyw sztucznych na skład produktów gazowych powstałych po detonacji materiału wybuchowego typu ANFO
Influence of the addition of plastics on the content of postdetonation gaseous products of ANFO explosive
Autorzy:: Biegańska, J.
Barański, K.
Tumen-Ulzii, G.
Powiązania:: https://bibliotekanauki.pl/articles/92622.pdf
Data publikacji:: 2018
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:: ANFO
tworzywa sztuczne
obliczenia termodynamiczne
plastics
thermodynamic calculations
Opis:: W artykule przedstawiono wyniki analizy termodynamicznej saletroli modyfikowanych dodatkiem tworzyw sztucznych. Analiza wykonana została w oparciu o program komputerowy ZMWCyw. Zaprezentowano zmiany składu powstałych produktów gazowych w zależności od procentowego dodatku wybranego polimeru. Dokonano analizy ilościowej oraz jakościowej pierwotnych gazów postrzałowych powstałych w wyniku detonacji zmodyfikowanych kompozycji ANFO.
The results of the analysis of thermodynamic ANFO explosive material modified with the addition of plastics, is presented. The analysis was made in the ZMWCyw computer program. Changes in the content of the resulting gaseous products depending on the percentage of the selected polymer are presented. Quantitative and qualitative analysis of primary gaseous products resulting from the detonation of modified ANFO compositions was performed.
Źródło:: Materiały Wysokoenergetyczne; 2018, T. 10; 5-12
2083-0165
Pojawia się w:: Materiały Wysokoenergetyczne
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 30.

Tytuł:: Thermodynamic assessment of crude distillation units: case studies of Nigeria refineries
Autorzy:: Osuolale, Funmilayo Nihinlola
Anozie, Ambrose Nwora
Powiązania:: https://bibliotekanauki.pl/articles/240552.pdf
Data publikacji:: 2019
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: crude distillation unit
exergy efficiency
refineries
thermodynamic analysis
Opis:: This paper presents the results of thermodynamic analysis of the crude distillation units of two refineries in Nigeria. The analysis was intended to assess the thermodynamic efficiencies of the refineries and proffer methods of improving the efficiencies. Presented results show the atmospheric distillation units of the refineries have 33.3% and 31.6% exergetic efficiencies and 86.5% and 74.6% energetic efficiencies, respectively. Modifications of the operating and feed conditions of the refineries resulted in increased exergetic efficiencies for as much as 62.3% and 38.7% for the refineries. Thermodynamic analysis of the refineries can bring about efficiency improvement and effectiveness of the refineries.
Źródło:: Archives of Thermodynamics; 2019, 40, 4; 83-102
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 31.

Tytuł:: A thermodynamic study on catalytic decomposition of hydrazine in a space thruster
Autorzy:: Pakdehi, Shahram
Shirvani, Fatemeh
Zolfaghari, Reihaneh
Powiązania:: https://bibliotekanauki.pl/articles/240211.pdf
Data publikacji:: 2019
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: catalytic thruster
hydrazine
ammonia
specific impulse
thermodynamic
analysis
Opis:: Most satellites stationed in space use catalytic propulsion systems for attitude control and orbit adjustment. Hydrazine is consumed extensively as liquid monopropellant, in the thrusters. Catalytic reactor is the most important section in the catalytic thruster. Ammonia and nitrogen gases are produced as a result of complete catalytic decomposition of hydrazine in the reactor, causing an increase in temperature and a rise in specific impulse. Ammonia is subsequently decomposed, leading to nitrogen and hydrogen gases. Decomposition of ammonia leads to a decrease in temperature, molecular weight and specific impulse. The latter phenomenon is unavoidable. The effect of ammonia decomposition on the reactor temperature, molecular weight of gaseous products and conclusively on specific impulse was studied in this article. At adiabatic state, thermodynamic analysis revealed that the maximum and minimum temperatures were 1655 K and 773 K, respectively. The highest molecular weight was obtained at ammonia conversion of zero and the lowest when ammonia conversion was 100%. The maximum specific impulse (305.4 S) was obtained at ammonia conversion of zero and completely conversion of ammonia, the minimum specific impulse (about 213.7 s) was obtained. For specific impulse, the result of thermodynamic calculation in this work was validated by the empirical results.
Źródło:: Archives of Thermodynamics; 2019, 40, 4; 151-166
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 32.

Tytuł:: Processing of phosphorites with extraction of phosphorus, obtaining calcium carbide and ferroalloy
Autorzy:: Shevko, Victor M.
Uteyeva, Raisa A.
Badikova, Alexandra D.
Tleuova, Saltanat T.
Powiązania:: https://bibliotekanauki.pl/articles/27323638.pdf
Data publikacji:: 2023
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: phosphorite
thermodynamic modeling
electrical melting
phosphorus
calcium carbide
ferroalloy
Opis:: The article considers the results of studying the thermodynamic computer modeling of the interaction of phosphorite (Karatau basin, Kazakhstan) with carbon and coke performed using the HSC-10 software package and electric smelting of the phosphorite with coke and steel shavings in an arc furnace. The modeling allowed us to determine the equilibrium extraction degrees of phosphorus into gas (Р2, Р4), silicon into ferroalloy in the form of iron silicides (FeSi2, FeSi, Fe3Si, Fe5Si3, Si) and calcium into CaС2. At temperatures above 1500 °C, regardless of the amount of iron, the extraction degree of phosphorus into gas is more 99%. The resulting ferroalloy contains 21.2-23.8% of Si, 1.6-2.8% of Al; the calcium carbide has a capacity of 288-325 dm3/kg. The extraction degree of silicon into the alloy was 89.8%, calcium in CaC2 – 72.5%, phosphorus into gas – 99.4%. The ferroalloy, formed at the electric smelting of the Chulaktau phosphorite together with coke and steel shavings and containing 24.9-29.8% of Si, is FS25 grade ferrosilicon, and the formed calcium carbide has a capacity of 278-290 dm3/kg and belongs to the third and second grades. The developed technology makes it possible to increase the degree of phosphorites’ comprehensive use two times (up to 87.5%).
Źródło:: Physicochemical Problems of Mineral Processing; 2023, 59, 6; art. no. 174463
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 33.

Tytuł:: AmiRNA Designer - new method of artificial miRNA design
Autorzy:: Mickiewicz, Agnieszka
Rybarczyk, Agnieszka
Sarzynska, Joanna
Figlerowicz, Marek
Blazewicz, Jacek
Powiązania:: https://bibliotekanauki.pl/articles/1038843.pdf
Data publikacji:: 2016
Wydawca:: Polskie Towarzystwo Biochemiczne
Tematy:: artificial miRNA
RNAi
gene regulation
sequence specific
thermodynamic profiles
Opis:: MicroRNAs (miRNAs) are small non-coding RNAs that have been found in most of the eukaryotic organisms. They are involved in the regulation of gene expression at the post-transcriptional level in a sequence specific manner. MiRNAs are produced from their precursors by Dicer-dependent small RNA biogenesis pathway. Involvement of miRNAs in a wide range of biological processes makes them excellent candidates for studying gene function or for therapeutic applications. For this purpose, different RNA-based gene silencing techniques have been developed. Artificially transformed miRNAs (amiRNAs) targeting one or several genes of interest represent one of such techniques being a potential tool in functional genomics. Here, we present a new approach to amiRNA*design, implemented as AmiRNA Designer software. Our method is based on the thermodynamic analysis of the native miRNA/miRNA* and miRNA/target duplexes. In contrast to the available automated tools, our program allows the user to perform analysis of natural miRNAs for the organism of interest and to create customized constraints for the design stage. It also provides filtering of the amiRNA candidates for the potential off-targets. AmiRNA Designer is freely available at http://www.cs.put.poznan.pl/arybarczyk/AmiRNA/.
Źródło:: Acta Biochimica Polonica; 2016, 63, 1; 71-77
0001-527X
Pojawia się w:: Acta Biochimica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 34.

Tytuł:: Evaluation of thermodynamic properties for the biosorption of chromium by using cherry leaves (Muntingia calabura L.)
Autorzy:: Aathithya, R.
Sowparnika, J.R.
Balakrishnan, V.
Powiązania:: https://bibliotekanauki.pl/articles/11897.pdf
Data publikacji:: 2014
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: thermodynamic property
biosorption
chromium
cherry
leaf
Muntingia calabura
entropy
Opis:: Chromium is a heavy metal which has widely used in tannery and electroplating industries. Contaminations of these industrial metals into the river possess major threat to an environment. Therefore, biosorption is a technique which is applied for the sorption of heavy metal by a biomaterial. In the present study reveals that cherry leaves was used as a biomaterial and for that the thermodynamic properties was evaluated for the biosorption of chromium. From the thermodynamic studies it was found that the reaction was feasible, spontaneous and exothermic because the values of ΔG = negative, ΔS = negative and ΔH = positive. So, it was concluded that the experiment was thermodynamically feasible.
Źródło:: International Letters of Natural Sciences; 2014, 20
2300-9675
Pojawia się w:: International Letters of Natural Sciences
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 35.

Tytuł:: Generalized thermoelastic interactions due to an inclined load at a two-temperature half-space
Autorzy:: Abouelregal, A. E.
Zenkour, A. M.
Powiązania:: https://bibliotekanauki.pl/articles/279661.pdf
Data publikacji:: 2016
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:: thermoelasticity
conductive and thermodynamic temperatures
half-space
inclined load
Opis:: The article presents a two-temperature theory to study the thermally insulated stress-free surface of a thermoelastic solid half-space due to an inclined load. The inclined load is a linear combination of a normal load and a tangential load. The normal mode analysis has been employed to solve the present problem. Variations of conductive and thermodynamic temperatures, displacements, and stresses distributions with the horizontal distance have been presented graphically. Some comparisons have been made to estimate the effects due to the two-temperature parameter and the inclination angle on the field quantities. Results of earlier works have been deduced from the present investigation as special cases.
Źródło:: Journal of Theoretical and Applied Mechanics; 2016, 54, 3; 827-838
1429-2955
Pojawia się w:: Journal of Theoretical and Applied Mechanics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 36.

Tytuł:: Wykorzystanie programu FactSage w projektowaniu stalowniczych żużli kadziowych
Application of FactSage software for designing of steelmaking ladle slags
Autorzy:: Różański, P.
Borecki, M.
Szypuła, I.
Powiązania:: https://bibliotekanauki.pl/articles/182360.pdf
Data publikacji:: 2012
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Metalurgii Żelaza im. Stanisława Staszica
Tematy:: modelowanie termodynamiczne
FactSage
stalownictwo
żużel
thermodynamic modeling
steelmaking
slag
Opis:: Komputerowe programy termochemiczne wraz z bazami danych, obejmującymi ciekłe stale, żużle i stałe roztwory tlenków coraz częściej wykorzystuje się do symulacji skomplikowanych reakcji chemicznych i równowag fazowych występujących w procesach wytwarzania stali. Dzięki temu można ograniczyć zakres eksperymentów w skali laboratoryjnej i przemysłowej, co pozwala skrócić czas i obniżyć koszty prac badawczo-rozwojowych. Za pomocą programu FactSage można obliczyć lepkość żużli oraz określić przebieg ich krzepnięcia przy użyciu modelu równowagowego lub modelu Scheil'a, wyznaczając temperatury likwidusu i solidusu oraz powstające fazy. Symulacje w układzie ciekła stal-żużel pozwalają oceniać zdolności rafinacyjne żużli, w tym zdolność odsiarczania lub odfosforowania kąpieli stalowej. Z kolei symulacje w układzie żużel - materiał ogniotrwały można wykorzystać w procesie doboru wymurówki roboczej urządzenia na linii żużla. W artykule przedstawiono przykłady wykorzystania programu FactSage w procesie doboru kadziowego żużla rafinacyjnego.
Computer programs with thermochemical databases, covering the liquid steels, slags and oxide solid solutions, are increasingly used to simulate complex chemical reactions and phase equilibria occurring in the steelmaking process. This enables to limit number of experiments in laboratory and industrial scale, which allows shortening the time and reducing the cost of research and development works. Slag viscosity can be calculated and slag solidification microstructure can be defined using the equilibrium solidification and Scheil's models by FactSage software. Simulations in the liquid steel - slag refining systems allow to assess the refining abilities of slags, including the desulfurization and dephosphorization ability of steel bath. The simulations in the system slag - refractory material can be used in selection of refractory materials for the slag line. The paper presents examples of thermochemical simulations made by FactSage used for selection of the ladle refining slag.
Źródło:: Prace Instytutu Metalurgii Żelaza; 2012, T. 64, nr 1, 1; 184-187
0137-9941
Pojawia się w:: Prace Instytutu Metalurgii Żelaza
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 37.

Tytuł:: Thermodynamic analysis of medium pressure reciprocating natural gas expansion engines
Autorzy:: Farzaneh-Gord, M.
Izadi, S.
Pishbin, S. I.
Sheikhani, H.
Deymi-Dashtebayaz, M.
Powiązania:: https://bibliotekanauki.pl/articles/777996.pdf
Data publikacji:: 2015
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: Expansion engine
thermodynamic
first law
optimization
ideal gas model
Opis:: Natural gas pressure has to be reduced from medium pressure of 1.724 MPa (250 psia) to lower pressure of 0.414 MPa (60 psia) at Town Border pressure reduction Station (TBS). Currently, the pressure reduction is carried out by throttling valves while considerable amount of pressure energy is wasted. One of the equipment which could be used to recover this waste energy is the reciprocating expansion engine. The purpose of this research is to simulate one-sided reciprocating expansion engine thermodynamically for TBS pressure range. The simulation is based on first law of thermodynamics, conversation of mass and ideal gas assumptions. The model could predict in-cylinder pressure and in-cylinder temperature at various crank angles. In addition, the effects of the engine geometrical characteristics, such as intake and exhaust port area and ports timing on the Indicated work per cycle output are investigated.
Źródło:: Polish Journal of Chemical Technology; 2015, 17, 2; 119-125
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 38.

Tytuł:: Thermodynamic Description of Ternary Fe-B-X Systems. Part 8: Fe-B-Mo, with Extension to Quaternary Fe-B-Cr-Mo System
Autorzy:: Miettinen, Jyrki
Visuri, Ville-Valtteri
Fabritius, Timo
Powiązania:: https://bibliotekanauki.pl/articles/2049544.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: phase diagrams
thermodynamic modeling
thermodynamic database
Fe-based systems
Fe-B-X systems
Fe-B-Mo system
Fe-B-Cr-Mo system
Opis:: Thermodynamic optimizations of the ternary Fe-B-Mo system and its binary sub-system B-Mo are presented. The Fe-B-Mo description is then extended to the quaternary Fe-B-Cr-Mo system by assessing the ternary B-Cr-Mo system. The thermodynamic descriptions of the other binaries (Fe-B, Fe-Cr, Fe-Mo, B-Cr, and Cr-Mo) and the other ternaries (Fe-B-Cr and Fe-Cr-Mo) are taken from earlier studies. In this study, the adjustable parameters of the B-Mo, Fe-B-Mo, and B-Cr-Mo systems were optimized using the experimental thermodynamic and the phase equilibrium data from the literature. The solution phases of the system (liquid, bcc and fcc) are described with the substitutional solution model, and most borides are treated as stoichiometric phases or semistoichiometric phases, using a simple two-sublattice model for the latter. The system’s intermetallic phases, Chi, Mu, R, and Sigma (not dissolving boron) as well as boride M3B2, based on a formulation of (Cr,Fe)(Cr,Fe,Mo)2(B)2, are described with a three-sublattice model. Reasonable agreement is obtained between the calculated and measured phase equilibria in all four systems: B-Mo; Fe-B-Mo; B-Cr-Mo; and Fe-B-Cr-Mo.
Źródło:: Archives of Metallurgy and Materials; 2021, 66, 1; 281-295
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 39.

Tytuł:: Free energy of helix propagation in short polyalanine chains determined from peptide growth simulations of La3+-binding model peptides. Comparison with experimental data
Autorzy:: Maciejczyk, Maciej
Hermans, Jan
Bierzyński, Andrzej
Powiązania:: https://bibliotekanauki.pl/articles/1041277.pdf
Data publikacji:: 2006
Wydawca:: Polskie Towarzystwo Biochemiczne
Tematy:: thermodynamics
peptide
helix-coil equilibrium
thermodynamic integration
molecular dynamics
Opis:: Molecular dynamics (MD) is, at present, a unique tool making it possible to study, at the atomic level, conformational transitions in peptides and proteins. Nevertheless, because MD calculations are always based on a more or less approximate physical model, using a set of approximate parameters, their reliability must be tested by comparison with experimental data. Unfortunately, it is very difficult to find a peptide system in which conformational transitions can be studied both experimentally and using MD simulations so that a direct comparison of the results obtained in both ways could be made. Such a system, containing a rigid α-helix nucleus stabilized by La3+ coordination to a 12-residue sequence taken from an EF-hand protein has recently been used to determine experimentally the helix propagation parameters in very short polyalanine segments (Goch et al. (2003) Biochemistry 42: 6840-6847). The same parameters were calculated here for the same peptide system using the peptide growth simulation method with, alternatively, charmm 22 and cedar potential energy functions. The calculated free energies of the helix-coil transition are about two times too large for cedar and even three times too large for charmm 22, as compared with the experimental values. We suggest that these discrepancies have their origin in the incorrect representation of unfolded peptide backbone in solution by the molecular mechanics force fields.
Źródło:: Acta Biochimica Polonica; 2006, 53, 1; 121-130
0001-527X
Pojawia się w:: Acta Biochimica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 40.

Tytuł:: Thermodynamic Phase Diagram and Phonon stability, Electronic and Optical Properties of FeVSb: A DFT study
Autorzy:: Bagheri, A.
Boochani, A.
Masharian, S. R.
Jafarpour, F. H.
Powiązania:: https://bibliotekanauki.pl/articles/2203753.pdf
Data publikacji:: 2023
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: DFT
thermodynamic phase diagram
phonon
electronic properties
optical properties
Opis:: Mechanical, electronic, thermodynamic phase diagram and optical properties of the FeVSb half-Heusler have been studied based on the density functional theory (DFT) framework. Studies have shown that this structure in the MgAgAs-type phase has static and dynamic mechanical stability with high thermodynamic phase consistency. Electronic calculations showed that this compound is a p-type semiconductor with an indirect energy gap of 0.39 eV. This compound’s optical response occurs in the infrared, visible regions, and at higher energies its dielectric sign is negative. The Plasmon oscillations have occurred in 20 eV, and its refraction index shifts to zero in 18 eV.
Źródło:: Archives of Metallurgy and Materials; 2023, 68, 1; 331--338
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 41.

Tytuł:: Thermodynamic calculation of a rotary engine with external heat supply based on the ideal rallis cycle
Autorzy:: Usenkov, Roman A.
Popov, Igor A.
Gortyshov, Yuri F.
Kokhanova, Svetlana Y.
Latypov, Ravil A.
Powiązania:: https://bibliotekanauki.pl/articles/2106207.pdf
Data publikacji:: 2022
Wydawca:: Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:: thermodynamic calculation
ideal cycle
work
heat
external combustion engine
Opis:: The design and kinematic scheme of the operation of a rotary external combustion engine with offset shafts have been developed. Expressions are obtained that make it possible to calculate the values of the increasing and decreasing functions of the working volume of the hot and cold cavities with a change in the angle of rotation of the rotor. An expression is obtained for calculating the compression ratio in the cold cavity of a rotary heat engine with an external heat supply. An expression has been determined that makes it possible to calculate the total torque of a rotary external combustion engine. A comparative analysis of the torque values of a rotary heat engine with an external heat supply and a Wankel engine is carried out. An assessment of the efficiency of an external combustion engine with offset shafts is carried out. Based on the thermodynamic calculations using ideal Erickson and Rallis cycles for a rotary external combustion engine, the processes occurring inside the hot and cold cavities of a heat engine are described. The thermodynamic condition parameters at the characteristic points of the cycle are determined and expressions are obtained that determine the thermal efficiency of the ideal Erickson and Rallis cycles in relation to the considered external combustion engine. A method for calculating the ideal cycle for an external combustion engine with offset shafts is presented.
Źródło:: Acta Mechanica et Automatica; 2022, 16, 1; 40--47
1898-4088
2300-5319
Pojawia się w:: Acta Mechanica et Automatica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 42.

Tytuł:: A comparative study of thermodynamic electrolyte models applied to the Solvay soda system
Autorzy:: Jaworski, Z.
Czernuszewicz, M.
Gralla, Ł.
Powiązania:: https://bibliotekanauki.pl/articles/185481.pdf
Data publikacji:: 2011
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: model termodynamiczny
elektrolit
thermodynamic model
electrolytes
activity coefficients
soda system
Opis:: Fast development of computation techniques for electrolyte activities contributed recently to introduction of a few substantial programmes for thermodynamic computing of multiphase systems. The presented study comprises useful information for practical computing using selected thermodynamic models of aqueous electrolyte solutions. Those models enable quantitative description of both phase and ionic equilibria and provide values of activity coefficients. The carried out analysis of individual models involved a comparison of their practical effectiveness features along with problems encountered in evaluation of the coefficients. The authors conclude that for the Solvay soda system the exUNIQUAC model for an in-house code or the MSE model for a commercial one can be used.
Źródło:: Chemical and Process Engineering; 2011, 32, 2; 135-154
0208-6425
2300-1925
Pojawia się w:: Chemical and Process Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 43.

Tytuł:: Alternative cogeneration thermodynamic cycles for domestic ORC
Autorzy:: Mikielewicz, D.
Wajs, J.
Mikielewicz, J.
Powiązania:: https://bibliotekanauki.pl/articles/185524.pdf
Data publikacji:: 2018
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: microcogeneration
thermodynamic cycle
power generation
mikrokogeneracja
cykl termodynamiczny
wytwarzanie energii
Opis:: The Organic Flash Cycle (OFC) is suggested as a vapor power cycle that could potentially improve the efficiency of utilization of the heat source. Low and medium temperature finite thermal sources are considered in the cycle. Additionally the OFC’s aim is to reduce temperature difference during heat addition. The study examines 2 different fluids. Comparisons are drawn between the OFC and an optimized basic Organic Rankine Cycle (ORC). Preliminary results show that ethanol and water are better suited for the ORC and OFC due to higher power output. Results also show that the single flash OFC achieves better efficiencies than the optimized basic ORC. Although the OFC improves the heat addition exergetic efficiency, this advantage was negated by irreversibility introduced during flash evaporation.
Źródło:: Chemical and Process Engineering; 2018, 39, 1; 75--84
0208-6425
2300-1925
Pojawia się w:: Chemical and Process Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 44.

Tytuł:: Thermodynamic properties of water sorption isotherms of grape seed
Autorzy:: Majd, K.M.
Karparvarfard, S.H.
Farahnaky, A.
Ansari, S.
Powiązania:: https://bibliotekanauki.pl/articles/24427.pdf
Data publikacji:: 2014
Wydawca:: Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:: thermodynamic property
water sorption
moisture sorption
isotherm
grape seed
seed
Opis:: In this study the moisture sorption isotherm of grape seed was determined by using a static gravimetric method at 35-65°C and 0.108-0.821 water activity range. The sorption isotherms were found to be typical sigmoid shape of most food materials. Five models including the Brunauer-Emmett-Teller (2-parameter), Guggenheim, Anderson and De Boer (3-parameter), Oswin (2-parameter), Ferro-Fontan (3-parameter) and Peleg (4-parameter) models were considered to fit the experimental data. The Ferro- Fontan and Peleg equations (at three temperatures 35, 45, 65°C) having R2 greater than 0.97 and lower values of standard error of estimate and deviation modulus gave the best fit of the experimental data throughout the entire range of water activity. The net isosteric heat of sorption, calculated by Calusius-Clapeyron equation on experimental data, was found to be a polynomial and exponential function of equilibrium moisture content within the temperature range investigated.
Źródło:: International Agrophysics; 2014, 28, 1
0236-8722
Pojawia się w:: International Agrophysics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 45.

Tytuł:: Dft investigation of a high energy density polynitro compound, 2,2’-Bis(trinitromethyl)-5,5’-azo-1,2,3,4- tetrazole
Autorzy:: Lin, H.
Zhu, S. G.
Chen, P. Y.
Li, K.
Li, H. Z.
Peng, X. H.
Powiązania:: https://bibliotekanauki.pl/articles/358030.pdf
Data publikacji:: 2013
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:: polynitro
electronic structure
thermodynamic properties
crystal structure
detonation performance
stability
Opis:: A novel polynitro compound, 2,2’-bis(trinitromethyl)-5,5’-azo- 1,2,3,4-tetrazole, was designed and investigated at the DFT-B3LYP/6-31G(d) level. Its properties, such as electronic structure, IR spectrum, heat of formation, thermodynamic properties and crystal structure, were predicted. This compound is most likely to crystallize in the P21 space group, and the corresponding cell parameters are Z = 2, a = 5.46 Å, b = 9.72 Å, c = 14.05 Å, α = 90°, β = 90°, γ = 90°. In addition, the detonation velocity and pressure were also estimated by using the empirical Kamlet-Jacobs equations, and were predicted to be 8.28 km/s and 31.61 GPa respectively. The oxygen balance of this compound is +13.79%, which indicates that it could serve as an oxidizer. Bond dissociation energy calculations show that the C(13)-N(21)O2 and C(14)-N(30)O2 bonds are the locations of thermal decomposition and that this compounds meets the thermal stability requirements as an exploitable explosive. Keywords: polynitro, electronic structure, thermodynamic properties, crystal structure, detonation performance, stability.
Źródło:: Central European Journal of Energetic Materials; 2013, 10, 3; 325-338
1733-7178
Pojawia się w:: Central European Journal of Energetic Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 46.

Tytuł:: Enthalpy of formation of intermetallic phases from Fe-Ni-Ti System. Comparative studies
Entalpia tworzenia faz międzymetalicznych z układu Fe-Ni-Ti. Studia porównawcze
Autorzy:: Gąsior, W.
Dębski, A.
Powiązania:: https://bibliotekanauki.pl/articles/356183.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: intermetallics
phase diagrams
thermodynamic and thermochemical properties
phase identification
calorimetry
Opis:: The solution calorimetric method was used for the measurement of the formation enthalpy of the binary FeTi and Fe2Ti intermetallic phases and of the FeNiTi2 phase from the region of the ternary B2 one. The FeNi and FeNiTi2 phases were prepared by levitation melting and the Fe2Ti phase - by melting the metals in a glove-box under high purity argon. The alloys obtained were identified by the X-ray diffraction analysis. The structural study of the alloys with the composition equal to the FeTi and Fe2Ti phase confirmed the mentioned phases mainly in the samples. In the case of the ternary alloy of the composition of the FeNiTi2 phase, a slight amount of iron was also found. The obtained values of the formation enthalpy equal as follows: -27.2±1.3 kJ/mole of atoms, -22.5±1.4 kJ/mole of atoms and -34.2±1.3 kJ/mole of atoms for the Fe2Ti, FeTi and FeNiTi2 phase, respectively.
Stosując kalorymetryczna metodę rozpuszczania zostały zmierzone entalpie tworzenia dwóch dwuskładnikowych faz międzymetalicznych FeTi i Fe2Ti oraz z obszaru fazy trójskładnikowej B2. Fazy FeTi i FeNiTi2 zostały przygotowane metoda lewitacyjnego topienia a faza Fe2Ti metoda metalurgiczna przez stopienie metali w komorze manipulacyjnej z atmosfera ochronna argonu wysokiej czystości. Otrzymane stopy były poddane identyfikacji metoda analizy dyfrakcji promieniowania rentgenowskiego. Badania te potwierdziły występowanie w próbkach dwuskładnikowych głównie faz FeTi i Fe2Ti. W przypadku stopu trójskładnikowego oprócz fazy FeNiTi2 została wykryta niewielka ilość żelaza. Zmierzone wartości entalpii tworzenia faz wynoszą: -27.2±1.3 kJ/mol atomów dla Fe2Ti, -22.5±1.4 kJ/mol atomów dla FeTi oraz -34.2±1.3 kJ/mol atomów dla FeNiTi2.
Źródło:: Archives of Metallurgy and Materials; 2012, 57, 4; 1095-1104
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 47.

Tytuł:: Research and development of a high-performance oxy-fuel combustion power cycle with coal gasification
Autorzy:: Kindra, Vladimir
Rogalev, Andrey
Zlyvko, Olga
Sokolov, Vladimir
Milukov, Igor
Powiązania:: https://bibliotekanauki.pl/articles/1955073.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: carbon dioxide
Oxy-fuel combustion
Gasification
energy efficiency
thermodynamic analysis
Opis:: Recent climate changes stimulate the search and introduction of solutions for the reduction of the anthropogenic effect upon the environment. Transition to the oxy-fuel combustion power cycles is an advanced method of CO2 emission reduction. In these energy units, the main fuel is natural gas but the cycles may also work on syngas produced by the solid fuel gasification process. This paper discloses a new highly efficient oxy-fuel combustion power cycle with coal gasification, which utilizes the syngas heat in two additional nitrogen gas turbine units. The cycle mathematics simulation and optimization result with the energy unit net efficiency of 40.43%. Parametric studies of the cycle show influence of the parameters upon the energy unit net efficiency. Change of the cycle fuel from natural gas to coal is followed by a nearly twice increase of the carbon dioxide emission from 4.63 to 9.92 gmCO2/kWh.
Źródło:: Archives of Thermodynamics; 2021, 42, 4; 155-168
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 48.

Tytuł:: Adsorption of CO2 by surface modified coal-based activated carbons: kinetic and thermodynamic analysis
Autorzy:: Xinzhe, Liu
Mingyang, Zhang
Juan, Chen
Zhengyu, Hu
Shuaifei, Xian
Mingxuan, Tang
Chenchen, Zhang
Powiązania:: https://bibliotekanauki.pl/articles/2174813.pdf
Data publikacji:: 2022
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: Surface modification
CO2 adsorption capacity
adsorption kinetics
thermodynamic parameters
Opis:: The effects of different surface modifiers on the CO2 adsorption capacity of coal-based activated carbons were studied, and the diffusion behavior, adsorption kinetics and thermodynamic parameters of CO2 in activated car-bons were analyzed. The results show that compared with ethylene glycol, 1,2-propylenediamine and zinc chloride, potassium hydroxide and sodium hydroxide can greatly improve CO2 adsorption capacity. The adsorption rate is faster, and the adsorption capacity is larger, with the maximum CO2 adsorption capacity being 33.54 mL/g. Fick’s law can well describe the diffusion behavior of CO2 in activated carbon. The addition of a surface modifier can increase the diffusion coefficient. The diffusion of CO2 in activated carbon falls into the category of crystal diffusion. The adsorption kinetics of CO2 before and after surface modification follow the Bangham equation. During the adsorption process, δ H < 0, δ G < 0, δ S < 0. Surface modification can reduce adsorption heat and promote adsorption, and the adsorption process is dominated by physisorption.
Źródło:: Polish Journal of Chemical Technology; 2022, 24, 3; 19--28
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 49.

Tytuł:: Experimental Study on Ammonium Nitrate(V)-based Solid Propellants for Fracturing Wells
Autorzy:: Hadzik, J.
Koślik, P.
Wilk, Z.
Frodyma, A.
Habera, Ł.
Powiązania:: https://bibliotekanauki.pl/articles/358138.pdf
Data publikacji:: 2017
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:: fracturing wells
solid propellants
ammonium nitrate(V)
polyurethanes
thermodynamic analyses
Opis:: This paper investigates the possibility of using ammonium nitrate(V)-based solid propellants for fracturing wells in borehole mining. Various modified propellant compositions with ammonium nitrate(V) and polyurethanes were prepared. Using laboratory rocket motors (LRMs) and underwater tests in pressure chambers, the energetic parameters (i.e., maximum pressure of the gaseous products and pressure impulse) for the selected AN-propellants were determined. Furthermore, thermodynamic analyses for these propellants were performed. The influence of the proposed additives on the energetic parameters (i.e., calorific value and specific energy) was shown. The gas volume generated per unit volume of propellant, which is an important parameter in the process of hydraulic fracturing, was estimated.
Źródło:: Central European Journal of Energetic Materials; 2017, 14, 3; 660-674
1733-7178
Pojawia się w:: Central European Journal of Energetic Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 50.

Tytuł:: Nonequilibrium state of engineering systems
Autorzy:: Dolinskii, A.
Draganov, B.
Kozirskii, V.
Powiązania:: https://bibliotekanauki.pl/articles/410714.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Oddział w Lublinie PAN
Tematy:: stan nierównowagi
systemy niestabilne
termodynamika
nonequilibrium state
unstable system
thermodynamic
Opis:: We present a characteristic of nonequilibrium phenomena and describe a method of determining the interdependence of thermodynamic forces and irreversible processes caused by them.
Źródło:: ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2012, 1, 1; 33-34
2084-5715
Pojawia się w:: ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 51.

Tytuł:: Characteristics of natural and synthetic molecular sieves and study of their interactions with fragrance compounds
Autorzy:: Kasperkowiak, M.
Strzemiecka, B.
Voelkel, A.
Powiązania:: https://bibliotekanauki.pl/articles/110548.pdf
Data publikacji:: 2016
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: molecular sieves
fragrance compounds
adsorption properties
thermodynamic parameters
thermal stability
Opis:: Structural, physicochemical and adsorption properties of two natural and one synthetic molecular sieves were investigated by various techniques: X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, low-temperature nitrogen adsorption and inverse gas chromatography. The influence of these properties on the ability to adsorb two model fragrances: p-cymene and menthol was studied. The free enthalpy, entropy and Gibbs free energy of adsorption of fragrance molecules on the surface of zeolite and zeolite-like materials were estimated by using inverse gas chromatography. Also, the influence of temperature on the stability of solid-fragrance compound systems as well as the release of the adsorbed fragrance compounds was studied. The obtained results exhibit that both porosity and chemical composition of molecular sieves influence the size and strength of adsorption of fragrance compounds. The study indicated different release characteristics for p-cymene and menthol.
Źródło:: Physicochemical Problems of Mineral Processing; 2016, 52, 2; 789-802
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 52.

Tytuł:: Phenol Biosorption from Polluted Aqueous Solutions by Ulva lactuca Alga Using Batch Mode Unit
Autorzy:: Abbas, Mohammed Nsaif
Al-Hermizy, Suadat Mustafa Mohammed
Abudi, Zaidun Naji
Ibrahim, Thekra Atta
Powiązania:: https://bibliotekanauki.pl/articles/124215.pdf
Data publikacji:: 2019
Wydawca:: Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:: sea lettuce
Ulva lactuca
adsorption
phenol
aqueous solutions
isotherm
thermodynamic
Opis:: This paper is related to study the using sea lettuce (Ulva lactuca) as a low-cost adsorbent for removing the phenol compounds from aqueous solutions by adsorption under different operating conditions in a batch unit. The SEM and FTIR tests were performed to determine the morphological characteristics and the functional groups existing on the adsorbent material, respectively, while the surface area was identified by means of two techniques which were blue color method and BET method. The results of the adsorption experiments showed that the efficiency of the removal process is inversely proportional with initial concentration of phenol, pH and temperature; while the efficiency was directly proportional to adsorbent amount, agitation speed and treatment time. The results showed that the percentage of removal of phenol from processed water solutions ranged from 25.446% to 90.125%. The Langmuir and Freundlich isotherm models were chosen to estimate the amounts of phenol adsorption by the sea lettuce powder. The kinetic study shows that the adsorption was obeyed pseudo second order also the thermodynamic parameters were calculated.
Źródło:: Journal of Ecological Engineering; 2019, 20, 6; 225-235
2299-8993
Pojawia się w:: Journal of Ecological Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 53.

Tytuł:: Analiza termodynamiczna procesu spalania mieszanin perchlorowanych węglowodorów z azydkiem sodu
Thermodynamic analysis of combustion in perchlorated hydrocarbons/sodium azide systems
Autorzy:: Szala, M.
Powiązania:: https://bibliotekanauki.pl/articles/210333.pdf
Data publikacji:: 2008
Wydawca:: Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:: synteza spaleniowa
analiza termodynamiczna
nanostruktury
combustion synthesis
thermodynamic analysis
nanostructures
Opis:: W pracy przedstawiono wyniki badań teoretycznych i eksperymentalnych dotyczących mechanizmu reakcji oraz składu skondensowanych produktów powstających podczas mieszanin perchlorowanych węglowodorów z azydkiem sodu. Analiza teoretyczna obejmowała obliczenia zmian parametrów termodynamicznych, takich jak entropia, entalpia i entalpia swobodna reakcji oraz wyznaczenie na podstawie przyjętych równań reakcji wydajności stałych produktów. Wykazano, że stałymi produktami spalania binarnych mieszanin tetrachlorometanu, heksachloroetanu, heksachlorobutadiemu i heksachlorocyklopentadienu z azydkiem sodu są cyjanek sodu, węgiel oraz chlorek sodu. Stwierdzono występowanie w produktach spalania enkapsulatów zawierajacych w swym wnętrzu krystality chlorku sodu.
Combustion reactions of perchlorated hydrocarbons with sodium azide mixtures were theoretically and experimentally investigated. Standard thermodynamic parameters like enthalpy, entropy and free enthalpy of assumed reactions were calculated. Reactions between these substrates are fast and exothermic enough to proceed at a high temperature and self-sustaining regime. Heat effects accompanying the reaction were measured and the presence of sodium cyjanide, sodium chloride and carbon in solid state reaction products were experimentally confirmed.
Źródło:: Biuletyn Wojskowej Akademii Technicznej; 2008, 57, 1; 203-213
1234-5865
Pojawia się w:: Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 54.

Tytuł:: Wood fibreboard paraffin hydrophobization and the impact of this treatment on the board surface finishing quality
Autorzy:: Kudela, Josef
Powiązania:: https://bibliotekanauki.pl/articles/24072362.pdf
Data publikacji:: 2019
Wydawca:: Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:: fibreboards
paraffin
surface treatment
coating materials
paint drying
thermodynamic characteristics
Opis:: Wood fibreboard paraffin hydrophobization and the impact of this treatment on the board surface finishing quality. The aim of this paper is to analyse the causes of surface treatment defects in commercially produced wood fibreboards (FB). The analysis of: the obtained (measured and calculated) thermodynamic characteristics and of the results of microscopic examinations demonstrated that the excessive FB hydrophobization with paraffin may cause the paraffin to release from the FB surface and to migrate into the first primer layer. For the sanded FBs, similar paraffin migration was also observed into the second primer layer. This entailed lowered drying rate for the coating materials applied on FB, lower adhesion of the coating materials to the substrate and also lower adhesion between the particular coating layers applied. At the same time, the occurring frequency of surface treatment defects increased.
Źródło:: Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology; 2019, 107; 115--123
1898-5912
Pojawia się w:: Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 55.

Tytuł:: Optimizing the shape of a compression-ignition engine combustion chamber by using simulation tests
Autorzy:: Pielecha, Ireneusz
Merkisz, Jerzy
Powiązania:: https://bibliotekanauki.pl/articles/962691.pdf
Data publikacji:: 2019
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:: CI engine combustion system
combustion process thermodynamic analysis
combustion chamber optimization
Opis:: Modern solutions used in compression-ignition internal combustion engines are quite similar to each other. The use of high-pressure, direct fuel injection results in high combustion rates with controlled exhaust emissions. One of the combustion system quality criteria is to obtain adequately high thermodynamic indicators of the combustion process, which are obtained through, among others, the right combustion chamber geometry. Its shape influences the fuel atomization process, turbulence of fuel dose, evaporation and the combustion process. Optimizing the combustion chamber shape is one of the decisive factors proving the correct execution of the combustion process. This article presents the methodology of choosing the combustion chamber shape (changes of three selected combustion chamber dimensions) by using the optimization methods. Generating multidimensional data while maintaining the correlation structure was performed by using the Latin hypercube method. Chamber optimization was carried out by using the Nelder-Mead method. The combustion chamber shape was optimized for three engine load values (determined by the average indicated pressure) at selected engine operating conditions. The presented method of engine combustion chamber optimization can be used in low and high speed diesel propulsion engines (especially in maritime transport applications).
Źródło:: Polish Maritime Research; 2019, 3; 138-146
1233-2585
Pojawia się w:: Polish Maritime Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 56.

Tytuł:: Mechanism and kinetics oxidation of inconel 617 and 625 alloys
Autorzy:: Staszewska, K.
Scendo, M.
Powiązania:: https://bibliotekanauki.pl/articles/134738.pdf
Data publikacji:: 2016
Wydawca:: ADVSEO
Tematy:: inconel alloy
thermogravimetric analysis
thermodynamic parameters
parabolic rate constants
activation energy
Opis:: The mechanism and kinetics of oxidation of Inconel 617 and 625 alloys in air atmosphere were investigated. Materials were examined by the thermogravimetric method. The X-ray diffraction spectrometer (XRD) was used to observation change in chemical composition the oxide scales of Inconel alloys specimens. Oxidation kinetics was determined from weight-change measurements. The surface and microstructure of the sample were observed in an optical microscope (OM) and a scanning electron microscope (SEM). The results showed that the oxide scales of the alloys were compact and continuous. The layer were contained as the outer of Cr2O3, and the internal of NiCr2O4 spinel, NiO and other oxides. Oxides’ scales with good adherence were formed on the surface of alloys. The kinetics and thermodynamic parameters of oxides formation were calculated and discussed for both alloys.
Źródło:: Technical Issues; 2016, 1; 82-89
2392-3954
Pojawia się w:: Technical Issues
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 57.

Tytuł:: Failure of gas turbine cone burner by carburization
Autorzy:: Ardy, H.
Putra, S.
Hardianto, T.
Powiązania:: https://bibliotekanauki.pl/articles/247322.pdf
Data publikacji:: 2012
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: gas turbine
cone burner
Hastelloy-X
carburization
microstructure
carbide
thermodynamic simulation
Opis:: Gas turbine for a power plant has 72 pieces of cone burner in its combustion chamber. High-speed diesel oil (HSD) is use as fuel to produce 130 MW of power at 3,000 rpm. The maximum temperature at the turbine inlet is estimated about 1087 centigrade and at the outlet is between 400-540oC. Sixty percent of the cone burner failed repetitively at one side of the tip-end after 6,000 hours of service. The refurbished cone burner has to be replaced by a new one after 18,000 of service-hours. The cone burner material is cast Hastelloy-X (nickel based alloys). Metallurgical analyses by microstructural observation using optical and scanning electron microscopes, and energy dispersive spectroscope have been performed to observe the change in burner microstructure. Thermodynamics analysis has been performed to obtain temperature distribution around the failed section. Two failed cone burners have been examined; cone burner that has not been repaired, and that has been repaired twice. Thermodynamics analysis result shown that the temperature around the failed section is between 897 to 1087 centigrade. Microstructure of the good part, far from the failed section, consists of cast structure of austenite matrix and fine carbide particles. Severe carbide precipitation and growth was observed on the failed section even the nominal carbon content in material is only 0.10 percent (max.). Severe carbide precipitation occurred because of carbon ingress from the environment (carburization) which combines with carbide forming elements in material (chromium, molybdenum, and tungsten). As a result, the corrosion and oxidation resistance of material decreased significantly after long time exposure at high temperature that led to oxidation, thinning, and failure of the cone burner tip. Failure only localized on one side of the tip-edge, therefore refurbishment by welding and coating can be performed to extend the life cycle of cone burner. The current examination results shows that the replacement cycle is not only limited to 18,000 hours but can also be extended to 48,000 hours.
Źródło:: Journal of KONES; 2012, 19, 2; 9-16
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 58.

Tytuł:: Selected thermodynamic aspects of liquefied natural gas (LNG) pipeline flow during unloading process
Autorzy:: Włodek, T.
Łaciak, M.
Powiązania:: https://bibliotekanauki.pl/articles/299121.pdf
Data publikacji:: 2015
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:: LNG
liquefied natural gas
unloading operations
thermodynamic processes
cryogenics
LNG terminal
Opis:: Liquefied natural gas (LNG) is transported by ships to unloading points on the LNG terminals, where the LNG is transported by above-ground superinsulated pipelines to storage tanks. Storage tanks are located a few hundred meters to several kilometers away from the unloading point. The article shows the changes in the basie thermodynamic parameters of liquefied natural gas during the flow in the pipeline modeled for an exemplary unloading process for different variants using Peng-Robinson equation of state.
Źródło:: AGH Drilling, Oil, Gas; 2015, 32, 2; 275-287
2299-4157
2300-7052
Pojawia się w:: AGH Drilling, Oil, Gas
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 59.

Tytuł:: Thermal Degradation Behaviour and Kinetics of aged TNT-based Melt Cast Composition B
Autorzy:: Singh, Arjun
Sharma, Tirupati Chander
Singh, Vasundhara
Mukherjee, Niladri
Powiązania:: https://bibliotekanauki.pl/articles/358256.pdf
Data publikacji:: 2019
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:: composition B
thermal degradation
thermogravimetry
Differential Scanning Calorimetry
kinetics
thermodynamic parameters
Opis:: In the present paper, three kinds of aged and freshly prepared 2,4,6-trinitrotoluene (TNT) based Composition B stockpiled, for a period of 20 and 32 years, were investigated for the effect of natural ageing on their thermal degradation behaviour and kinetic parameters. The properties investigated indicated that there was no significant change in the thermal stability of the samples aged under natural environmental conditions. The kinetic parameters were studied by means of the Kissinger method using the peak temperature at maximum reaction rate from DSC data, and the isoconversional Kissinger-Akahira-Sunnose (KAS) and ASTM E689 methods from TGA data. The apparent activation energies calculated by the Kissinger method were 173.8 kJ·mol–1 for fresh, 170.4 kJ·mol–1 for 20 y old and 187.1 kJ·mol–1 for 32 y old Composition B, respectively. The values calculated by the KAS method were found to be in the range 77.2-235.8 kJ·mol–1 for fresh Composition B, 75.7-224.0 kJ·mol–1 for 20 y old and 70.4-196.0 kJ·mol–1 for 30 y old Composition B, respectively. The activation energies obtained from the KAS methods are in good agreement and consistent with the isoconversional ASTM E689 kinetic method. The thermodynamic parameters, such the Gibbs free energy of activation (ΔG#), activation enthalpy (ΔH#) and activation entropy (ΔS#) for the formation of activated complexes were also studied and are discussed.
Źródło:: Central European Journal of Energetic Materials; 2019, 16, 3; 360-379
1733-7178
Pojawia się w:: Central European Journal of Energetic Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 60.

Tytuł:: A Predictive Method for the Heat of Explosion of Non-ideal Aluminized Explosives
Autorzy:: Zhang, Q.
Chang, Y.
Powiązania:: https://bibliotekanauki.pl/articles/358737.pdf
Data publikacji:: 2013
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:: aluminized explosives
heat of explosion
thermodynamic
nonideal explosives
high energy materials
Opis:: The heat of explosion is one of the most important thermodynamic parameters of aluminized explosives. Two improvements in numerical calculations to predict the behaviour of the explosion of non-ideal aluminized explosives were completed in this work. The chemical reaction between aluminum and the C-J detonation products of high energy ingredients was determined and the equation of state for the detonation products of high energy ingredients was revised. The constant k in the BKW equation was revised to obtain perfect results for predicting the C-J parameters for high energy ingredients. The predicted results show that the heats and temperatures of aluminized explosives become maximized when the mass fraction of aluminum powder is 30%, which is in good agreement with the results obtained by empirical formulae.
Źródło:: Central European Journal of Energetic Materials; 2013, 10, 4; 541-554
1733-7178
Pojawia się w:: Central European Journal of Energetic Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 61.

Tytuł:: Pattern Selection in the Frame of Thermodynamic Similarity between Eutectics: Cu-Cu2O and (Zn)-Zn16Ti – Experiment
Autorzy:: Wołczyński, W.
Powiązania:: https://bibliotekanauki.pl/articles/353292.pdf
Data publikacji:: 2018
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: minimum entropy production
regular eutectics
irregular eutectics
droplets coagulation
thermodynamic competition
Opis:: Coagulation and solidification of the copper droplets suspend in the liquid slag are usually accompanied by the appearance of the Cu-Cu₂ O eutectic. Locally, this eutectic is created in the stationary state. Therefore, frequently it has a directional morphology. Since the E = (Zn) + Zn₁₆ Ti – eutectic is similar in the asymmetry of the phase diagram to the Cu-Cu₂ O – eutectic, the (Zn) single crystal strengthened by the E = (Zn) + Zn₁₆ Ti precipitate is subjected to directional growth by the Bridgman’s system and current analysis. Experimentally, the strengthening layers (stripes) are generated periodically in the (Zn) – single crystal as a result of the cyclical course of precipitation which accompanies the directional solidification. These layers evince diversified eutectic morphologies like irregular rods, regular lamellae, and regular rods. The L – shape rods of the Zn₁₆ Ti – intermetallic compound appear within the first range of the growth rates when the irregular eutectic structure is formed. Next, the branched rods transform into regular rods and subsequently the regular rods into regular lamellae transitions can be recorded. The regular lamellae exist only within a certain range of growth rates. Finally, the regular rods re-appear at some elevated growth rates. The entropy production per unit time and unit volume is calculated for the regular eutectic growth. It will allow to formulate the entropy production per unit time for both eutectic structure: rod-like and lamellar one.
Źródło:: Archives of Metallurgy and Materials; 2018, 63, 3; 1555-1564
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 62.

Tytuł:: Thermodynamic Analysis and Mathematic Modeling of Waste Sludge from Drinking Water Treatment Plants
Autorzy:: Azeddine, Fantasse
El Khadir, Lakhal
Ali, Idlimam
Powiązania:: https://bibliotekanauki.pl/articles/2026746.pdf
Data publikacji:: 2022
Wydawca:: Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:: drinking water sludge
sludge valorization
wastewater management
thermodynamic analysis
isosteric heat
Opis:: Water treatment annually produces a huge amount of Drinking Water Treatment Sludge (DWTS) wastes. The latter causes environmental problems in Morocco in terms of energy and pollution. Therefore, cost-effective and eco-friendly solutions for managing them should be proposed in order to reduce the frequency of storage along with transportation costs. In this paper, a thermodynamic analysis of DWTS wastes was conducted based on the isosteric heat and compensation theory. Different results concerning the mineralogical identification of sludges were established. Findings revealed that the by-product of water purification was mainly composed of aluminum, silica and iron hydroxides, with pH varying between 6.23 and 6.85. The suspended matter was between 18.3 and 19.6 m/l. The volatile matter of the three sludge samples was between 18 and 21%. The measured dry matter content was between 13.41 and 15.23%. The experimental tests were performed under temperatures from 45 and 60 °C, the experimental data of the sorption curves were fitted by using several models of correlation. Furthermore, the analysis showed that the Peleg’s model perfectly described the isotherm curves in the activities ranging from 0 to 90%. The net isosteric heats of sorption of the three hydroxide sludge from the Moroccan treatment station: $S_k$, $S_m$ and $S_s$, were determined for desorption and adsorption. Moreover, it was revealed that the equilibrium water content rising lead contributed to the reduction of the net isosteric heat and the entropy of sorption. Finally, the enthalpy-entropy compensation showed that the sorption mechanism involved was enthalpy driven.
Źródło:: Journal of Ecological Engineering; 2022, 23, 2; 140-149
2299-8993
Pojawia się w:: Journal of Ecological Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 63.

Tytuł:: Phase equilibria for liquefi eld natural gas (LNG) as a multicomponent mixture
Autorzy:: Włodek, T.
Powiązania:: https://bibliotekanauki.pl/articles/299072.pdf
Data publikacji:: 2015
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:: LNG
liquefied natural gas
thermodynamic processes
cryogenics
VLE calculations
phase equilibria
Opis:: Liquefied natural gas (LNG) has an increasingly important role in the global natural gas market. Global demand for natural gas will grow over the coming years. LNG is transported by ships to unloading points on the storage terminals. During the LNG unloading and storage processes some part of LNG evaporates into gas phase and causes changes in the composition of stored LNG. The main component of LNG is methane, the remaining components are primarily ethane, propane, butane and nitrogen. Depending on the participation of these components the basic thermodynamic parameters of LNG can significantly change. LNG is also product sensitive to changes of temperature. In order to better prediction of changes of individual paramete rs of stored LNG caused by changes of temperature and LNG composition vapor-liquid equilibrium (VLE) calculations are performed for cryogenic conditions using equations of state.
Źródło:: AGH Drilling, Oil, Gas; 2015, 32, 3; 539-550
2299-4157
2300-7052
Pojawia się w:: AGH Drilling, Oil, Gas
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 64.

Tytuł:: A thermodynamic analysis of a gas-steam turbine incorporating a full model of a spray – ejector condense
Autorzy:: Ziółkowski, P.
Powiązania:: https://bibliotekanauki.pl/articles/175324.pdf
Data publikacji:: 2018
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: computational ﬂow mechanics modelling
two-phase ejector
thermodynamic analysis
numerical analysis
Opis:: The speciﬁc issues that occur in the mathematical modelling of a spray-ejector condenser have been presented. The results of a thermodynamic analysis of a steam-gas turbine cycle have been obtained by computational ﬂow mechanics code. The main aim of the spray-ejector condenser is simultaneously condensing steam and compressing CO2 from the condensation pressure to about 100 kPa. Hence, the most important innovation of this steam-gas cycle emerges as the enhanced condensation, which is based on the nano-injection of cold water and a jet-powered compression of CO2 performed in the spray-ejector condenser.
Źródło:: Transactions of the Institute of Fluid-Flow Machinery; 2018, 139; 63-96
0079-3205
Pojawia się w:: Transactions of the Institute of Fluid-Flow Machinery
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 65.

Tytuł:: Possibility of the charge exchange work diminishing of an internal combustion engine in part load
Autorzy:: Postrzednik, S.
Żmudka, Z.
Powiązania:: https://bibliotekanauki.pl/articles/247156.pdf
Data publikacji:: 2011
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: engine efficiency
charge exchange work
engine load
valve actuating
thermodynamic cycle
Opis:: Internal combustion engines, used for driving of different cars, occur not only at the full load, but mostly at the part load. The relative load exchange work at the full (nominal) engine load is significant low. At the part load of the IC engine his energy efficiency r)e is significantly lower than in the optimal (nominal field) range of the performance parameters. One of the numerous reasons of this effect is regular growing of the relative load exchange work of the IC engine. The load exchange work of IC engine essentially determines the effective engine efficiency. It is directly connected with the quantitative regulation method common used in the IC engines. From the thermodynamic point of view - the main reason of this effect is the throttling process (causing exergy losses) occurring in the inlet and outlet channels. The known proposals for solving of this problem are based on applying of the fully electronic control of the motion of inlet, outlet valves and new reference cycles. The independent actuating (steerage) procedures of the ICE inlet valves should assure the adequate mass of the fresh charge, while procedures of the outlet valves are focused on the optimal exhaust gas recirculation rate, according to the engine load. The idea presented in the paper leads to diminishing the charge exchange work of the IC engines. The mentioned above problem can be solved using presented in the paper a new concept of the reference cycle (called as eco-cycle) of IC engine.
Źródło:: Journal of KONES; 2011, 18, 4; 377-387
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 66.

Tytuł:: Preliminary analysis of thermodynamic cycle of turbofan engine fuelled by hydrogen
Autorzy:: Marszalek, N.
Powiązania:: https://bibliotekanauki.pl/articles/247482.pdf
Data publikacji:: 2018
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: liquid hydrogen
turbofan engine
turbine cooling
engine thermodynamic cycle
engine performance
Opis:: Presented article is focus on analysis of the effect of hydrogen fuel on turbofan engine performance. Selected properties of hydrogen and possibility of introduction in civil aviation were discussed. Hydrogen implementation as aviation fuel offers obvious advantages such as low emission of combustion product, higher payload, lower fuel consumption, general availability but also poses great technical challenges. The most important aspect is to ensure engine operational safety at very high level. Hydrogen implementation would eliminate the aviation dependence of exhausting sources of fossil fuels especially of crude oil. The thermodynamic model of turbofan engine was implemented in MATLAB environment. Accepted assumptions have been discussed. Turbine cooling process has been included in the numerical model. Working fluid was modelled as semi-perfect gas. Analysis was carried out for take-off and design point conditions. Engine performances were compared for two kinds of applied fuels: liquid hydrogen and commonly used in turbine engines kerosene. Combustion heat of hydrogen is about three time higher than in comparison with conventional turbine engine fuel, what exert significant influence on engine performance. The results of engine thermodynamic cycle analysis indicate the increase in specific thrust and significant reduction of specific fuel consumption. The results are presented in tabular form and on the graphs. Obtained results have been discussed and the direction of further research was indicated.
Źródło:: Journal of KONES; 2018, 25, 3; 347-354
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 67.

Tytuł:: Predicted Crystal Structures, Analysis, Impact Sensitivities and Morphology of Solid High-Energy Complexes: Alkaline-Earth Carbohydrazide Perchlorates
Autorzy:: Liu, Y.
Zhang, R.
Feng, C.-G.
Yang, L.
Zhang, T.-L.
Powiązania:: https://bibliotekanauki.pl/articles/358890.pdf
Data publikacji:: 2015
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:: crystal structure
density of state
thermodynamic property
impact sensitivity
crystal morphology
Opis:: The crystal structures, density of states, energy gap, thermodynamic properties, impact sensitivities and morphology of beryllium carbohydrazide perchlorate ([Be(CHZ)3](ClO4)2), magnesium carbohydrazide perchlorate ([Mg(CHZ)3](ClO4)2), calcium carbohydrazide perchlorate ([Ca(CHZ)3] (ClO4)2), strontium carbohydrazide perchlorate ([Sr(CHZ)3](ClO4)2) and barium carbohydrazide perchlorate ([Ba(CHZ)3](ClO4)2) were investigated using the density functional theory (DFT) and crystal morphology theory. The results show that all of the complexes have six-coordinated distorted octahedra, which is different from previous works. This was rationalised by consideration of the intermolecular interactions in the crystal structures. Hence the crystal structure is now more reliable. The chemical reactions of the whole molecule may be triggered by an electron transition of CHZ or ClO4 −. Furthermore the energy gaps were observed, and the values of the impact sensitivities were inferred to have the following sequence: [Be(CHZ)3](ClO4)2 > [Mg(CHZ)3](ClO4)2 > [Sr(CHZ)3](ClO4)2 > [Ca(CHZ)3](ClO4)2 > [Ba(CHZ)3](ClO4)2. In addition, the thermodynamic equations at 25-1000 K were obtained. The positive values of the standard molar free enthalpies shows that carbohydrazide perchlorates are stable at 298.15 K. The (1 0 -1) and (0 0 2) faces are the most important growth directions of the crystal morphologies, and have the minimum growth rates. From the cleaved main growth faces, it can be deduced that surface active agents with active hydrogen atoms in the functional groups could be used as crystal-control reagents to control the crystal morphology for alkaline-earth carbohydrazide perchlorates.
Źródło:: Central European Journal of Energetic Materials; 2015, 12, 2; 229-248
1733-7178
Pojawia się w:: Central European Journal of Energetic Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 68.

Tytuł:: TEMPERATURE DEPENDENT SOLUBILITY STUDIES OF BRIGATINIB IN SOME PURE SOLVENTS USEFUL IN DOSAGE FORM DEVELOPMENT
Autorzy:: MOHAMMAD, MUQTADER
ANWER, Md Khalid
FATIMA, FARHAT
ALSHAHRANI, SAAD M.
ALSHETAILI, ABDULLAH S.
ALALAIWE, AHMED
ALSULAYS, BADER B.
SHAKEEL, FAIYAZ
Powiązania:: https://bibliotekanauki.pl/articles/895362.pdf
Data publikacji:: 2019-04-30
Wydawca:: Polskie Towarzystwo Farmaceutyczne
Tematy:: Lung cancer
curve fitting
Thermodynamic dissolution
mole fraction solubility
Apelblat model
Opis:: In the current study, thermodynamic dissolution of brigatinib in six pure solvents namely, water, ethanol, isopropyl myristate (IPM), poly(ethylene glycol)-400 (PEG-400), dichloromethane (DCM) and ethyl acetate (EA) at (298.2-323.2K) temperature and 0.1 MPa atm. pressure were carried out using flask shaking technique.The mole-fraction solubility of brigatinib was obtainedgreatest in IPM (6.09 x 10-2) and least in water (3.12 x 10-6) at298.2 K.Experimentally obtained solubilities values of brigatinib were regressed using adapted Apelblat equation with root mean square deviations in the range of 1.91 to 4.67 in all solvents and similar trends were observed with increased the temperature. The solubility data generated in this investigation could be helpful for investigator for analysis/dosage form development of brigatinib.
Źródło:: Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 2; 225-232
0001-6837
2353-5288
Pojawia się w:: Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 69.

Tytuł:: Entall - thermodynamic database of alloys
Entall - termodynamiczna baza danych stopów
Autorzy:: Dębski, A.
Powiązania:: https://bibliotekanauki.pl/articles/355184.pdf
Data publikacji:: 2013
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: database
thermodynamic properties
hydrogen storage
bazy danych
właściwości termodynamiczne
magazynowanie wodoru
Opis:: Li-Si, Ag-Ca, B-Li, Ca-Li and Al-Li belong to the group of application alloys. The Entall database includes experimental data on the enthalpy of formation of the intermetallic phases belonging to the mentioned systems, as well as software for the calculation of other thermodynamic functions. The presented Entall database is the first proposal of a thermodynamic property data, which will be gradually extended by new metal alloy systems. It is a free database, available at www.entall.imim.pl.
Stopy Li-Si, Ag-Ca. B-Li, Ca-Li. oraz Al-Li należą do grupy stopów, mających zastosowania aplikacyjne. Baza Entall zawiera eksperymentalne dane entalpii tworzenia faz międzymetalicznych należących do cytowanych układów oraz oprogra- mowanie dające możliwość wyliczenia innych funkcji termodynamicznych. Prezentowana baza Entall jest pierwszą propozycją bazy właściwości termodynamicznych, która będzie stopniowo rozbudowywana o nowe układy stopów metali. Jest to baza darmowa i dostępna pod adresem www.entall.imim.pl.
Źródło:: Archives of Metallurgy and Materials; 2013, 58, 4; 1147-1148
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 70.

Tytuł:: Thermodynamic indexes of real driving conditions of gasoline and LPG fuelled engine
Autorzy:: Pielecha, I.
Cieślik, W.
Bueschke, W.
Skowron, M.
Powiązania:: https://bibliotekanauki.pl/articles/223652.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: liquefied petroleum gas
combustion engine
thermodynamic indexes
ropa naftowa
silnik spalinowy
Opis:: The aim of the conducted tests was to assess the method of delivering additional fuel dose in transient conditions and to determine the impact of this additional fuel dose on the engine operation conditions. The experimental tests were conducted in typical urban driving conditions. In the study was used system for indicating and acquisition of fast-varying data; the combustion pressure in the first cylinder of the 3-cylinder engine with spark ignition was measured, as well as the voltage on the petrol injectors and the liquefied petroleum gas injector. The post-processing analysis enabled defining engine operation indexes taking into account the aforementioned parameters. Also indicated mean effective pressure, the heat release rate and the amount of the heat released were analysed. In addition, the indexes of transient conditions of engine operation per one cycle were specified: change of the engine speed, of the maximum combustion pressure, of the indicated mean effective pressure and change of the heat release rate.
Źródło:: Archives of Transport; 2016, 40, 4; 51-64
0866-9546
2300-8830
Pojawia się w:: Archives of Transport
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 71.

Tytuł:: Alternatywne wersje ewolucji a problem wszechmocy Boga
The Alternative Versions of Evolution and the Problem of God’s Omnipotence
Autorzy:: Życiński, Józef
Powiązania:: https://bibliotekanauki.pl/articles/2013188.pdf
Data publikacji:: 2008
Wydawca:: Katolicki Uniwersytet Lubelski Jana Pawła II. Towarzystwo Naukowe KUL
Tematy:: celowość
determinizm
ewolucja
termodynamika
wszechmoc
zło
determinism
evil
evolution
omnipotence
teleology
thermodynamic
Opis:: The author discusses the question whether an alternative version of cosmological and bio-logical evolution could have been actualized to eliminate negative phenomena specific for evolutionary processes in our universe. Specifically, one tries to answer whether the omnipotent God could have created quite different world with different logical principles and diverse laws of nature. Maybe such a world would be better than our universe regarded by Leibniz as the best of all possible universes. In trying to solve this problem, one has to remember that the process of evolution co-directs the created world to Divine ideals, values, and purposes; it does not, however, destroy by a logic of necessity or by a determinism of events, which would limit the freedom of creation. It does not eliminate pain and it does not change suffering into joy; it only shows the deepest meaning of the struggles thanks to which biological pain manifests its creative role.
Źródło:: Roczniki Filozoficzne; 2008, 56, 1; 363-377
0035-7685
Pojawia się w:: Roczniki Filozoficzne
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 72.

Tytuł:: Peculiarities of hydrocarbon systems of Ukrainian fields
Cechy charakterystyczne nietypowych układów węglowodorów w złożach na Ukrainie
Autorzy:: Fedyshyn, V.
Bahniuk, M.
Powiązania:: https://bibliotekanauki.pl/articles/300327.pdf
Data publikacji:: 2008
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:: złoża węglowodorów
kondensat gazowy
badania termodynamiczne
hydrocarbon fields
gas condensation
thermodynamic investigations
Opis:: On the territory of Ukraine within Dniepro-Donets depression a number of oil and gas condensate pools with atypical for them properties has been revealed. These are hydrocarbon formation fluids of transitional state with initial gas content over 800-1000 m3/m3 in oils or content of fraction C5+ in gas over 1000 cm3/m3. Under such conditions it becomes complicated to define pool type (phase state), since well-known numerical classifications with the use of different physical-chemical characteristics and their ratio turn out to be ineffective. In particular, the formation hydrocarbons of Sary field horizon V-18 simultaneously have the indications typical for oil and condensates. Phase state of such formation systems can be established only during special thermodynamic investigations in installations of phase equilibrium under condition that liquid-gas ratio in production of wells is properly measured. Even, insignificant deviations in the value of this ratio lead to phase equilibrium displacement in experiments and errors in determination of formation hydrocarbon fluid type.
Na obszarze Zagłębia Dnieprowsko-Donieckiego na Ukrainie odkryto kilka złóż ropy i kondensatu o nietypowych cechach. Są to węglowodorowe płyny złożowe w stanie przejściowym o początkowej zawartości gazu powyżej 800-1000 m3/m3 w ropach lub zawartość frakcji C5+ w gazie powyżej 1000 cm3/m3. W takich warunkach trudne jest określenie stanu fazowego, gdyż dobrze znane klasyfikacje numeryczne z wykorzystaniem różnych fizykochemicznych charakterystyk i ich stosunków okazują się nieskuteczne. W szczególności, formacje zawierające węglowodory w horyzoncie V-18 na złożu Sary jednocześnie mają wskazania typowe dla ropy naftowej i kondensatu. Stan fazowy takich formacji można określić jedynie w czasie specjalistycznych badań termodynamicznych w instalacjach z równowagą faz pod warunkiem, że w produkowanej substancji właściwie określono wielkość stosunku cieczy do gazu. Nawet niewielkie odchylenia w wartości tego współczynnika prowadzą do przesunięcia punktu równowagi fazowej w badaniach i błędnej klasyfikacji płynu złożowego.
Źródło:: Wiertnictwo, Nafta, Gaz; 2008, 25, 2; 259-264
1507-0042
Pojawia się w:: Wiertnictwo, Nafta, Gaz
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 73.

Tytuł:: The influence of chosen operation parameters on the efficiency of supercritical power plant
Wpływ wybranych parametrów pracy na efektywność bloku nadkrytycznego
Autorzy:: Bartela, Ł.
Kotowicz, J.
Michalski, S.
Powiązania:: https://bibliotekanauki.pl/articles/360235.pdf
Data publikacji:: 2011
Wydawca:: Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:: obieg parowy
analiza termodynamiczna
parametry pracy
steam cycle
thermodynamic analysis
operation parameters
Opis:: In the paper the evaluation of applied solutions, as well as the operational parameters in context of achieved efficiency of steam cycle of a supercritical power plant was carried out. The analysis for the referred structure of a power plant was made. The thermodynamic computational model was created in GateCycle software. In the calculations, the basic assumption was the maintenance of constant gross power of power plant. For this purpose, in the model the flow of live steam entering steam cycle was changed. In the first step the assumptions for three cases of unit were determined. First of all, the variants differ from each other with live and reheated steam parameters. The parameters for the two examined cases can be regarded as possible to be currently achieved in a modern supercritical power plants, while the third case represents a perspective variant. Based on relevant data implemented into the computational model, the relevant results for quantities characterizing the operation of examined units were generated. Among others, in the analysis the values of following quantities were determined: steam cycle efficiency, gross overall efficiency and specific consumption of heat. In the paper the assumptions, as well as the results are shown in the form of tables. The conclusions from comparison of results for individual solutions are also formulated.
W artykule dokonano oceny stosowanych rozwiązań, jak również parametrów pracy, w kontekście uzyskiwanej sprawności obiegu parowego bloku nadkrytycznego. Analiza wykonana została dla określonej struktury elektrowni. Termodynamiczny model obliczeniowy utworzono w programie GateCycle. W trakcie obliczeń podstawowym założeniem było utrzymanie mocy elektrycznej brutto bloku na stałym poziomie. W tym celu w modelu uzmienniano strumień pary świeżej wprowadzanej do części parowej układu. W pierwszej kolejności określono założenia liczbowe dla trzech wariantów bloku. Warianty przede wszystkim różnią się między sobą parametrami pary świeżej oraz wtórnie przegrzanej. Parametry dla dwóch badanych przypadków mogą być traktowane, jako aktualnie możliwe do osiągnięcia w nowoczesnych blokach na parametry nadkrytyczne, z kolei wariant trzeci reprezentuje rozwiązanie perspektywiczne. Na podstawie danych wprowadzonych do modelu obliczeniowego wygenerowano odpowiednie rezultaty dla wielkości charakteryzujących pracę badanych układów. W analizie określono wartość między innymi dla takich wielkości, jak: sprawność obiegu parowego, sprawność wytwarzania energii elektrycznej brutto oraz jednostkowe zużycie ciepła. Zarówno dane, jak i wyniki przedstawione są w pracy w formie tabel. W artykule sformułowano wnioski wynikające z zestawienia wyników uzyskanych dla poszczególnych rozwiązań.
Źródło:: Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2011, 27 (99) z. 1; 5-11
1733-8670
2392-0378
Pojawia się w:: Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 74.

Tytuł:: Analiza zmian składu chemicznego koksu wielkopiecowego w zakresie temperatur 800÷2500 K
Analysis of changes in the chemical compositions of blast furnace coke in temperature range 800÷2500 K
Autorzy:: Konstanciak, A.
Powiązania:: https://bibliotekanauki.pl/articles/181494.pdf
Data publikacji:: 2015
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Metalurgii Żelaza im. Stanisława Staszica
Tematy:: koks
analiza termodynamiczna
gaz
faza skondensowana
coke
thermodynamic analysis
gas
condensed phase
Opis:: W artykule przedstawiono zmiany składu chemicznego koksu zawierającego 11% popiołu w procesie wielkopiecowym. Obliczenia termodynamiczne przeprowadzono z wykorzystaniem programu FactSage. Ze względu na dużą liczbę tworzących się produktów reakcji chemicznych w obrębie składników popiołu, rozważano tylko 10 najważniejszych związków biorących udział w reakcjach. Mają one wpływ na przebieg redukcji oraz tworzenia się żużla w procesie wielkopiecowym.
The article presents changes in the chemical composition of coke containing 11% of ash in blast furnace process. Thermodynamic calculations were performed by means of FactSage programme. Due to high number of products formed in chemical reactions from the components of the ash, only 10 most important chemical compounds were considered. They influence the course of the reduction reaction and the formation of slag in the blast furnace process.
Źródło:: Prace Instytutu Metalurgii Żelaza; 2015, T. 67, nr 4, 4; 50-53
0137-9941
Pojawia się w:: Prace Instytutu Metalurgii Żelaza
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 75.

Tytuł:: Chalcones: A Solubility study at different temperatures
Autorzy:: Bhalu, A. A.
Bhesaniya, K. D.
Vekariya, N. J.
Baluja, S. H.
Powiązania:: https://bibliotekanauki.pl/articles/412118.pdf
Data publikacji:: 2014
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: Chloroform
dichloromethane
thermodynamic parameters
dissolution enthalpy
Gibb’s energy and en tropy
Opis:: Some new chalcones are synthesized by the condensation of aryl ketones with aromatic aldehydes and solubility of these synthesized chalcones is determined in chloroform and dichloromethane at temperatures ranging between 293.15 K and 313.15 K by gravimetric method. The experimental data was correlated well with modified Apelblat equation. Further, from the experimental solubility data, some thermodynamic parameters such as dissolution enthalpy, Gibb’s energy and entropy etc. were evaluated using van’t Hoff equation. The positive Gibb’s energy and negative entropy suggests spontaneous dissolution and more ordered structure in solution.
Źródło:: International Letters of Chemistry, Physics and Astronomy; 2014, 12; 7-19
2299-3843
Pojawia się w:: International Letters of Chemistry, Physics and Astronomy
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 76.

Tytuł:: Experimental study on thermodynamics of Cu-Pb-Ti and Cu-Pb-V alloys
Badania właściwości termodynamicznych stopów Cu-Pb-Ti oraz Cu-Pb-V
Autorzy:: Romanowska, J.
Powiązania:: https://bibliotekanauki.pl/articles/176043.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: copper alloys
thermodynamic activity
interaction parameter
stopy miedzi
aktywność termodynamiczna
parametr oddziaływania
Opis:: The thermodynamic activity of Pb in liquid Cu-Pb-Ti and Cu-Pb-V alloys has been determined by the equilibrium saturation method at T=1473K. The Cu-Pb alloy was accepted as a reference mixture. The interaction parameters of titanium and vanadium on the lead activity, ε^Ti_Pb> and ε^V_Pb, were calculated on the basis of experimental results. Negative values of these parameters suggest that titanium and vanadium decrease lead activity in the studied alloys.
Aktywność termodynamiczną ołowiu w ciekłych stopach Cu-Pb-Ti oraz Cu-Pb-V wyznaczono metodą równowagowego nasycania. Badania prowadzono w temperaturze 1473 K. Roztworem wzorcowym był ciekły stop Cu-Pb. Na podstawie wyników wykonanych doświadczeń obliczono wartości parametrów oddziaływania tytanu i wanadu na aktywność ołowiu ε^Ti_Pb oraz ε^V_Pb. Ujemne wartości parametrów oddziaływania sugerują, że tytan i wanad zmniejszają aktywność termodynamiczną ołowiu w badanych stopach Cu-Pb-Ti i Cu-Pb-V.
Źródło:: Advances in Manufacturing Science and Technology; 2016, 40, 2; 79-86
0137-4478
Pojawia się w:: Advances in Manufacturing Science and Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 77.

Tytuł:: Simultaneous thermodynamic simulation of CNG filling process
Autorzy:: Deymi-Dashtebayaz, M.
Farzaneh-Gord, M.
Reza Rahbari, H
Powiązania:: https://bibliotekanauki.pl/articles/779861.pdf
Data publikacji:: 2014
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: compressed natural gas
cascade storage bank
fast filling process
thermodynamic analysis
entropy
Opis:: In CNG station, the fuel is usually stored in the cascade storage bank to utilize the station more efficiently. The cascade storage bank is generally divided into three reservoirs, commonly termed low, medium and high-pressure storage bank. The pressures within these reservoirs have huge effects on the performance of the stations. In the current study, a theoretical simulation based on mass balance and thermodynamic laws has been developed to study the dynamic fast fi lling process of vehicle’s (NGV) cylinder from the cascade storage bank. The dynamic change of the parameters within the storage bank is also considered. Natural gas is assumed to contain only its major component, methane, and so thermodynamic properties table has been employed for finding the thermodynamics properties. Also the system is assumed as a lumped adiabatic system. The results show that the initial pressure of the cascade storage bank has a big effect on the storage bank volumes for bringing up the NGV cylinder to its target pressure (200 bar). The results also showed that ambient temperature has effect on the refueling process, chiefly the final NGV cylinder and the cascade storage bank conditions.
Źródło:: Polish Journal of Chemical Technology; 2014, 16, 1; 7-14
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 78.

Tytuł:: Temperature influence on the electrode process in the presence of 6-thioguanine and surfactants
Autorzy:: Nosal-Wiercińska, Agnieszka
Kaliszczak, Waldemar
Martyna, Marlena
Szabelska, Anna
Gołębiowska, Beata
Wiśniewska, Małgorzata
Powiązania:: https://bibliotekanauki.pl/articles/1845199.pdf
Data publikacji:: 2020
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: catalytic effect
Bi(III) electroreduction
6-thioguanine
surfactants
thermodynamic parameters
kinetic parameters
Opis:: The measurements concerning the process of the electroreduction of Bi(III) ions in the presence of 6–thioguanine (6TG) and Triton X-100 as well as Tween 80 in the 2 $mol·dm^{-3}$ chlorates(VII) demonstrate a dependence of the process rate on temperature. The applied electrochemical techniques (DC polarography, cyclic and SWV voltammetry) allowed to determine the kinetic and thermodynamic parameters as well as their correlation with changes in kinetics of the electrode process. The catalytic activity of 6TG was confirmed by the decrease of overall enthalpies of activation. Different values of $\DeltaH^{\ne}$ and $\DeltaS^0$ for Bi(III) electroreduction in the presence of 6–thioguanine as well as Triton X-100 and Tween 80 suggest changes in kinetics of the electrode process towards inhibition.
Źródło:: Physicochemical Problems of Mineral Processing; 2020, 56, 6; 14-21
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 79.

Tytuł:: Analiza teoretyczna procesu kutrowania w aspekcie termodynamicznym
Theoretical analysis of mechanical meat cutting process in thermodynamic aspect
Autorzy:: Szeląg, M.
Powiązania:: https://bibliotekanauki.pl/articles/292121.pdf
Data publikacji:: 2011
Wydawca:: Polskie Towarzystwo Inżynierii Rolniczej
Tematy:: kutrowanie
termodynamiczny układ otwarty
dyssypacja
mechanical meat cutting
thermodynamic open system
dissipation
Opis:: W pracy przedstawiono analizę teoretyczną procesu kutrowania i wynikające stąd efekty termodynamiczne. Wyróżniony układ roboczy, złożony z misy kutra wypełnionej farszem mięsnym i zespołu noży, rozpatrywany jest jako termodynamiczny układ otwarty, przyrównywany do układu tribologicznego. Dokonano podziału pracy tarcia i oporów tarcia na część cieplną i mechaniczną rozpatrywanego układu.
The paper presents theoretical analysis of the process involving cutting meat by means of mechanical cutters and resultant thermodynamic effects. Separated working system, consisting of cutter pan filled with meat stuffing and a set of knives, is considered as a thermodynamic open system compared to a tribological system. The researchers divided friction work and frictional resistance into thermal and mechanical part of the discussed system.
Źródło:: Inżynieria Rolnicza; 2011, R. 15, nr 4, 4; 257-264
1429-7264
Pojawia się w:: Inżynieria Rolnicza
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 80.

Tytuł:: Adsorption and Thermodynamic Studies for Corrosion Inhibition of API 5L X-52 Steel in 2 M HCl Solution by Moxifloxacin
Autorzy:: Ikpi, M. E.
Abeng, F. E.
Obono, O. E.
Powiązania:: https://bibliotekanauki.pl/articles/1118241.pdf
Data publikacji:: 2017
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: API 5L X-52 steel
corrosion inhibition
moxifloxacin and adsorption
thermodynamic
Opis:: The inhibition of API 5L X-52 steel corrosion in an acidic medium by moxifloxacin at 303 K, 313 K and 323 K was monitored by potentiodynamic polarization measurement. The concentration of acid medium was maintained throughout the experiment. The inhibition efficiency was found to increased with increase in concentration of moxifloxacin and temperature. Activation energy, adsorption and thermodynamic parameters were evaluated from the study temperature. Herein, moxifloxacin brought about a decrease in activation energy Ea that reflects chemisorption. The adsorption of the moxifloxacin on the steel surface was found to obeyed Langmuir adsorption isotherm ΔGads values, indicating strong and spontaneous adsorption of the moxifloxacin on the surface of API 5L X-52 steel.
Źródło:: World News of Natural Sciences; 2017, 9; 52-61
2543-5426
Pojawia się w:: World News of Natural Sciences
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 81.

Tytuł:: Formation and Thermodynamic Analyses of Inclusions in Ti-Containing Steel Weld Metals with Different Al Contents
Autorzy:: Wang, Bingxin
Jiang, Yingtian
Powiązania:: https://bibliotekanauki.pl/articles/2049426.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: thermodynamic calculation
electron probe micro-analyzer
oxide inclusion
aluminium content
phase diagram
Opis:: Ti-containing steel weld metals with Al contents of 0.01-0.085% were prepared. The effects of Al contents on the inclusions evolution were investigated by means of thermodynamic calculations coupled with electron probe micro-analyses and transmission electron microscopy. The results show that the inclusions in the 0.01% Al weld metal are mainly composed of ilmenite withsome amounts of (Mn-Si-Al)-oxide and titanial_spinel. When Al content is increased up to 0.035%, a more amount of corundum and a small amount of pseudobrookite are formed. In 0.085% Al weld metal, the (Mn-Si-Al)-oxide disappears completely, and the inclusions contain a substantial amount of corundum, in addition to a minimal amount of pseudobrookite. Ti3O5, MnTi2O4 and MnTiO3 are the primary constituents of pseudobrookite, titanial_spinel and ilmenite, respectively. Titanial_spinel and ilmenite have higher amounts of Mn, but lower Ti levels compared with pseudobrookite. In the case of presence of a considerable amountsof titanial_spinel and ilmenite, Mn-depleted zone is formed in matrix around the inclusions.
Źródło:: Archives of Metallurgy and Materials; 2021, 66, 1; 171-180
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 82.

Tytuł:: Study of thermal degradation behavior and kinetics of ABS/PC blend
Autorzy:: Bano, Saira
Ramzan, Naveed
Iqbal, Tanveer
Mahmood, Hamayoun
Saeed, Farhan
Powiązania:: https://bibliotekanauki.pl/articles/778844.pdf
Data publikacji:: 2020
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: ABS/PC blend
thermal degradation
iso-conversional analysis
activation energy
thermodynamic parameters
Opis:: This work investigated kinetics and thermal degradation of acrylonitrile butadiene styrene and polycarbonate (ABS/PC) blend using thermogravimetric analysis in the range of 25 to 520°C. For thermal degradation of blend, activation energy (E_a) and pre-exponential factor (A) were calculated under various heating rates as 5, 10, 15 and 20°C/min using iso-conversional model-free methods (Kissinger, Flynn-Wall- Ozawa and Friedman). Mass loss of the blend as a function of temperature was plotted as thermogravimetric curve (TG) while derivative values of mass loss were drawn as derivative thermogravimetric (DTG) curve. Using Kissinger method, Ea was 51.4 kJ/mol, while values calculated from FWO and Friedman method were 86–161 and 30–251 kJ/mol respectively. Results showed increasing trend of E_a with higher conversion values indicating different degradation mechanisms at the initial and final stages of the experiment. Thermodynamic parameters such as enthalpy change (ΔH), Gibbs free energy (ΔG) and entropy change (ΔS) were also calculated.
Źródło:: Polish Journal of Chemical Technology; 2020, 22, 3; 64-69
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 83.

Tytuł:: New Features of Entall Database: Comparison of Experimental and Model Formation Enthalpies
Nowe funkcje bazy danych Entall: porównanie doświadczalnych i modelowych entalpii tworzenia
Autorzy:: Dębski, A.
Dębski, R.
Gąsior, W.
Powiązania:: https://bibliotekanauki.pl/articles/353128.pdf
Data publikacji:: 2014
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: COST 535
database
thermodynamic properties
Miedema model
baza
właściwości termodynamiczne
model Miedemy
Opis:: This paper presents a new version of the Entall database of the thermodynamic properties of metals and their alloys. The changes are related to the thermodynamic data of new binary and ternary systems as well as the integration of the database with an application for the modeling of the formation enthalpies of intermetallic phases with the use of the Miedema model. Using this tool, calculations of the enthalpies of formation of 38 intermetallic phases from 12 binary systems were performed and a comparative analysis conducted. The results of the analysis clearly showed a weak correlation between the model and experimental data. To improve this correlation, an intermediate method of proportional change was proposed, on the basis of the measurement of the enthalpy of formation for one of the phases. The values for the other phases obtained from this indirect method should not deviate much from the experimental ones provided that before the measurements (dissolving or pulping) or after them (direct synthesis), the phase being examined should undergo structural tests, in order to confirm its dominating amount in the samples.
W pracy przedstawiona została nowa wersja bazy właściwośsci termodynamicznych metali i stopów Entall. Modyfikacja dotyczyła z jednej strony danych termodynamicznych nowych układów dwu i trójskładnikowych a z drugiej zaadaptowania do niej opracowanego programu (kalkulatora) do modelowania entalpii tworzenia faz międzymetalicznych modelem Miedemy. Korzystając z tego nowego narzędzia wykonane zostały obliczenia entalpii tworzenia dla 38 faz międzymetalicznych z 12 układów dwuskładnikowych oraz przeprowadzona została analiza porównawcza. Wyniki analizy pokazały jednoznacznie słaba korelacje między danymi modelowymi i doświadczalnymi. Dla poprawienia tej korelacji zaproponowana została pośrednia metoda proporcjonalnej zmiany w oparciu o pomiar entalpii tworzenia dla jednej z faz. Uzyskane z tej pośredniej metody wartości dla innych faz powinny niewiele odbiegąc od eksperymentalnych przy spełnieniu warunku, że faza dla której wykonywane były badania została przed pomiarami (rozpuszczanie lub roztwarzanie) lub po nich (bezpośrednia synteza) poddana badaniom strukturalnym, w celu potwierdzenia jej dominującej ilości w próbkach.
Źródło:: Archives of Metallurgy and Materials; 2014, 59, 4; 1337-1343
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 84.

Tytuł:: Wpływ objętości próbki chemoutwardzalnej żywicy poliestrowej na przebieg jej utwardzania
Effect of the specimen volume of chemosetting polyester resin on the curing process
Autorzy:: Kozioł, M.
Mocek, P.
Jankowski, P.
Powiązania:: https://bibliotekanauki.pl/articles/947015.pdf
Data publikacji:: 2016
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
Tematy:: żywica poliestrowa
proces utwardzania
model termodynamiczny
polyester resin
curing process
thermodynamic model
Opis:: Zbadano wpływ objętości próbki żywicy poliestrowej na przebieg zmian temperatury oraz na czas utwardzania. Stwierdzono, że wraz ze zwiększającą się objętością próbki żywicy (do 120 cm3) skraca się czas sieciowania i rośnie temperatura maksymalna (szczytu egzotermicznego). Sztywność żywicy utwardzanej za pomocą aktywniejszego inicjatora maleje ze wzrostem objętości próbki, natomiast w przypadku zastosowania mniej aktywnego inicjatora — się zwiększa. Przeprowadzono modelowanie matematyczne termodynamicznego procesu utwardzania żywicy za pomocą modelu układu o parametrach rozłożonych, opisującego sieciowanie determinowane chemicznie z dyfuzją ciepła. Stwierdzono duży wpływ chłodzenia konwekcyjnego na przebieg procesu.
The paper presents an experimental evaluation of the influence of polyester resin specimen volume on the time and temperature of curing process. It was found that the maximum peak temperature increased with an increase of the resin volume up to 120 cm³ (Figs. 4—6) while the curing time was decreased. The stiffness of the resin cured with the use of a more active initiator decreased with an increase in the resin volume and increased when a less active initiator was employed (Figs. 9 and 10). The mathematical modelling of the thermodynamics of curing process was performed using a model of distributed parameters system, describing the chemically determined curing process with heat diffusion. A strong influence of convective cooling on the course of the process was found.
Źródło:: Polimery; 2016, 61, 2; 133-141
0032-2725
Pojawia się w:: Polimery
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 85.

Tytuł:: Assessment of thermodynamic cycle of internal combustion engine in terms of rightsizing
Autorzy:: Sroka, Zbigniew J.
Dworaczyński, Maciej K.
Powiązania:: https://bibliotekanauki.pl/articles/133097.pdf
Data publikacji:: 2019
Wydawca:: Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:: internal combustion engine
thermodynamic cycle
rightsizing
silnik o spalaniu wewnętrznym
obieg termodynamiczny
Opis:: The modification of the downsizing trend of internal combustion engines towards rightsizing is a new challenge for constructors. The change in the displacement volume of internal combustion engines accompanying the rightsizing idea may in fact mean a reduction or increase of the defining swept volume change factors and thus may affect the change in the operating characteristics as a result of changes in combustion process parameters - a research problem described in this publication. Incidents of changes in the displacement volume were considered along with the change of the compression space and at the change of the geometric degree of compression. The new form of the mathematical dependence describing the efficiency of the thermodynamic cycle makes it possible to evaluate the operation indicators of the internal combustion engine along with the implementation of the rightsizing idea. The work demonstrated the invariance of cycle efficiency with different forms of rightsizing.
Źródło:: Combustion Engines; 2019, 58, 3; 182-186
2300-9896
2658-1442
Pojawia się w:: Combustion Engines
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 86.

Tytuł:: Thermo-economic analysis and environmental aspects of absorption refrigeration unit operation onboard marine vehicles: RO- PAX vessel case study
Autorzy:: Ammar, N. R.
Sediek, I. S.
Powiązania:: https://bibliotekanauki.pl/articles/260242.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:: ship emissions
IMO
lithium bromide-water ARU
thermodynamic analysis
economic and environmental analysis
Opis:: Marine diesel engines lose a huge amount of fuel heat content in the form of exhaust gas and jacket cooling water, especially onboard high-powered marine vehicles such as Ro-Pax ships. In this paper, the possibility of using the waste heat of marine diesel engines as a source of heat for air conditioning absorption system is investigated. The thermodynamic analysis, in addition to the environmental and economic analysis of the air condition absorption cycle operated with two heat sources using lithium bromide as absorbent, are performed using the Engineering Equation Solver (EES) software. The last 10 years have seen a steady growth in the passenger ferry and Ro-Pax market, with particularly strong growth in passenger numbers. As a case study, a Ro-Pax vessel operating in the Red Sea area is considered, regarding the profitability of using air conditioning absorption system. The results show specific economic benefits of the jacket cooling water operated absorption refrigeration unit (ARU) over the exhaust gas operated unit, with annual costs of capital money recovery of 51,870 $/year and 54,836 $/year, respectively. Environmentally, applying an ARU machine during cruising will reduce fuel consumption by 104 ton/year. This, in turn, will result in reducing NOx, SOx, and CO2 emissions with cost-effectiveness of 7.73 $/kg, 20.39 $/kg, and 0.13 $/kg, respectively.
Źródło:: Polish Maritime Research; 2018, 3; 94-103
1233-2585
Pojawia się w:: Polish Maritime Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 87.

Tytuł:: Analiza termodynamiczna i ekonomiczna hierarchicznej dwuobiegowej elektrowni jądrowej z dwustopniowym rozprężaniem i dwustopniowym sprężaniem w obiegu Joule’a w zakresie wysokich temperatur
Autorzy:: Bartnik, Ryszard
Powiązania:: https://bibliotekanauki.pl/articles/2096866.pdf
Data publikacji:: 2022
Wydawca:: Nowa Energia
Tematy:: analiza termodynamiczna
elektrownia jądrowa
wysokie temperatury
thermodynamic analysis
nuclear power plant
high temperatures
Opis:: W pracach [1, 2, 3] przedstawiono termodynamiczną i ekonomiczną analizę innowacyjnej, hierarchicznej elektrowni jądrowej z jednym, chłodzonym helem wysokotemperaturowym reaktorem HTGR (rys. 1). W elektrowni realizowane są dwa obiegi Joule’a, jeden wysokotemperaturowy, drugi niskotemperaturowy. Oba obiegi charakteryzują się pojedynczymi stopniami rozprężania i sprężania helu. W niniejszej pracy przedstawiono natomiast analizę termodynamiczną i ekonomiczną elektrowni z dwoma wysokotemperaturowymi reaktorami HTGR (rys. 2).
Źródło:: Nowa Energia; 2022, 1; 82-94
1899-0886
Pojawia się w:: Nowa Energia
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 88.

Tytuł:: Wskaźniki pracy silnika spalinowego z bezpośrednim wtryskiem benzyny podczas przyspieszania
Indexes of operation of combustion engine with direct gasoline injection during accelerating
Autorzy:: Pielecha, I.
Cieślik, W.
Borowski, P.
Skowron, M.
Bueschke, W.
Powiązania:: https://bibliotekanauki.pl/articles/134116.pdf
Data publikacji:: 2015
Wydawca:: Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:: silnik spalinowy
nieustalone warunki pracy
analiza termodynamiczna
combustion engine
transient conditions
thermodynamic analysis
Opis:: Silniki o zapłonie iskrowym z wtryskiem bezpośrednim w coraz większym stopniu zastępują silniki z wtryskiem pośrednim benzyny. Wymusza to konieczność prowadzenia badań tych jednostek w nieustalonych warunkach pracy. Celem badań była analiza nieustalonych w arunków podczas swobodnego przyspieszania silnikiem oraz przyspieszania pojazdem. Wykorzystanie systemu do analizy procesów szybkozmiennych pozwoliło na ocenę wskaźników pracy silnika w warunkach swobodnego przyspieszania i przyspieszania pojazdu przy jednoczesnym oszacowaniu strat i sprawności mechanicznej turbodoładowanego silnika z bezpośrednim wtryskiem benzyny.
Engines with spark ignition and direct injection more and more often replace those with indirect gasoline injection. Due to this it is necessary to conduct tests of those engines in transient operational conditions. The aim of these tests was the analysis of such conditions during free engine acceleration and vehicle acceleration. The use of the system for the analysis of the fast-varying processes enabled estimation of indexes of engine operation during free acceleration and vehicle acceleration and, at the same time, estimation of the losses and mechanical efficiency of the turbocharged engine with direct gasoline injection.
Źródło:: Combustion Engines; 2015, 54, 3; 291-299
2300-9896
2658-1442
Pojawia się w:: Combustion Engines
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 89.

Tytuł:: Numerical thermodynamic optimization of supercritical coal fired power plant with support of IPSEpro software
Autorzy:: Elsner, W.
Kowalczyk, Ł.
Marek, M.
Powiązania:: https://bibliotekanauki.pl/articles/240118.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: optymalizacja termodynamiczna
siłownia nadkrytyczna
symulacja
wydajność
efficiency
simulation
supercritical power plant
thermodynamic optimization
Opis:: The paper presents a thermodynamic optimization of supercritical coal fired power plant. The aim of the study was to optimize part of the thermal cycle consisted of high-pressure turbine and two chosen high-pressure feed water heaters. Calculations were carried out using IPSEpro software combined with MATLAB, where thermal efficiency and gross power generation efficiency were chosen as objective functions. It was shown that the optimization with newly developed framework is sufficiently precise and its main advantage is the reduction of computation time on comparison to the classical method. The calculations have shown the tendency of the increase in efficiency, with the rise of a number of function variables.
Źródło:: Archives of Thermodynamics; 2012, 33, 3; 101-110
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 90.

Tytuł:: Characteristics modeling for supercritical circulating fluidized bed boiler working in oxy-combustion technology
Autorzy:: Balicki, A.
Bartela, Ł.
Powiązania:: https://bibliotekanauki.pl/articles/240453.pdf
Data publikacji:: 2014
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: thermodynamic analysis
oxy-combustion
supercritical CFB boiler
analiza termodynamiczna
oksyspalanie
nadkrytyczny kocioł CFB
Opis:: Among the technologies which allow to reduce greenhouse gas emission, mainly carbon dioxide, special attention deserves the idea of 'zero-emission' technology based on boilers working in oxy-combustion technology. In the paper the results of analyses of the influence of changing two quantities, namely oxygen share in oxidant produced in the air separation unit, and oxygen share in oxidant supplied to the furnace chamber on the selected characteristics of a steam boiler including the degree of exhaust gas recirculation, boiler efficiency and adiabatic flame temperature, was examined. Due to the possibility of the integration of boiler model with carbon dioxide capture, separation and storage installation, the subject of the analysis was also to determine composition of the flue gas at the outlet of a moisture condensation installation. Required calculations were made using a model of a supercritical circulating fluidized bed boiler working in oxy-combustion technology, which was built in a commercial software and in-house codes.
Źródło:: Archives of Thermodynamics; 2014, 35, 2; 51-63
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 91.

Tytuł:: Analiza termodynamiczna procesu spalania biomasy
Autorzy:: Łapczyńska-Kordon, B.
Frączek, J.
Powiązania:: https://bibliotekanauki.pl/articles/311608.pdf
Data publikacji:: 2011
Wydawca:: Instytut Naukowo-Wydawniczy "SPATIUM"
Tematy:: kotły energetyczne
spalanie biomasy
analiza termodynamiczna
power boilers
combustion of biomass
thermodynamic analysis
Opis:: W artykule została przedstawiona analiza termodynamiczna spalania rozdrobnionych roślin energetycznych, oparta na bilansie substancji. Z pomocą obliczeń stechiometrycznych określono rzeczywiste zapotrzebowanie powietrza, ilości spalin suchych oraz ich skład. Wyniki obliczeń porównano z pomiarami wykonanymi na stanowisku laboratoryjnym podczas spalania wierzby energetycznej, miskanta olbrzymiego i ślazowca pensylwańskiego.
This paper was presented thermodynamic analysis of combustion particulate feedstock, based on the balance sheet of the substance. With the help of stoichiometric calculations determined the actual air demand, the amount of dry flue gas and its composition. The calculation results were compared with measurements made on a laboratory during the combustion of the willow, the miscanthus and the Virginia mallow.
Źródło:: Autobusy : technika, eksploatacja, systemy transportowe; 2011, 12, 10; 298-304
1509-5878
2450-7725
Pojawia się w:: Autobusy : technika, eksploatacja, systemy transportowe
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 92.

Tytuł:: Performance of cryogenic oxygen production unit with exhaust gas bleed for sewage sludge gasification and different oxygen purities
Autorzy:: Kaszuba, Maja
Ziółkowski, Paweł
Mikielewicz, Dariusz
Powiązania:: https://bibliotekanauki.pl/articles/27312208.pdf
Data publikacji:: 2023
Wydawca:: Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:: thermodynamic analysis
oxy-combustion of syngas
BECCS
cryogenic air separation
penalty production
oxygen production
Opis:: The paper presents a thermodynamic analysis of the integration of a cryogenic air separation unit into a negative CO2 emission gas power plant. The power cycle utilizes sewage sludge as fuel so this system fits into the innovative idea of bioenergy with carbon capture and storage. A cryogenic air separation unit integrated with the power plant was simulated in professional plant engineering and thermodynamic process analysis software. Two cases of the thermodynamic cycle have been studied, namely with the exhaust bleed for fuel treatment and without it. The results of calculations indicate that the net efficiencies of the negative CO2 emission gas power plant reach 27.05% (combustion in 95.0% pure oxygen) and 24.57% (combustion in 99.5% pure oxygen) with the bleed. The efficiencies of the cycle without the bleed are 29.26% and 27.0% for combustion in 95.0% pure oxygen and 99.5% pure oxygen, respectively. For the mentioned cycle, the calculated energy penalty of oxygen production was 0.235 MWh/kgO2 for the lower purity value. However, for higher purity namely 99.5%, the energy penalty of oxygen production for the thermodynamic cycle including the bleed and excluding the bleed was indicated 0.346 and 0.347 MWh/kgO2, respectively. Additionally, the analysis of the oxygen purity impact on the carbon dioxide purity at the end of the carbon capture and storage installation shows that for the case with the bleed, CO2 purities are 93.8% and 97.6%, and excluding the bleed they are 93.8% and 97.8%, for the mentioned oxygen purities respectively. Insertion of the cryogenic oxygen production installation is required as the considered gas power plant uses oxy-combustion to facilitate carbon capture and storage method.
Źródło:: Archives of Thermodynamics; 2023, 44, 3; 63--81
1231-0956
2083-6023
Pojawia się w:: Archives of Thermodynamics
Dostawca treści:: Biblioteka Nauki

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Tytuł:: Functional dependence of thermodynamic and thermokinetic parameters of refrigerants used in mine air refrigerators. Part 1 – Refrigerant R407C
Zależności funkcyjne parametrów termodynamicznych i termokinetycznych czynników chłodniczych stosowanych w górniczych chłodziarkach powietrza. Część 1 – Czynnik chłodniczy R407C
Autorzy:: Nowak, B.
Życzkowski, P.
Łuczak, R.
Powiązania:: https://bibliotekanauki.pl/articles/219737.pdf
Data publikacji:: 2017
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: czynniki chłodnicze
R407C
parametry termodynamiczne i termokinetyczne
refrigerants
thermodynamic and thermokinetic parameters
Opis:: The authors of this article dealt with the issue of modeling the thermodynamic and thermokinetic properties (parameters) of refrigerants. The knowledge of these parameters is essential to design refrigeration equipment, to perform their energy efficiency analysis, or to compare the efficiency of air refrigerators using different refrigerants. One of the refrigerants used in mine air compression refrigerators is R407C. For this refrigerant, 23 dependencies were developed, determining its thermodynamic and thermokinetic parameters in the states of saturated liquid, dry saturated vapour, superheated vapor, subcooled liquid, and in the two-phase region. The created formulas have been presented in Tables 2, 5, 8, 10 and 12, respectively. It should be noted that the scope of application of these formulas is wider than the range of changes of that refrigerant during the normal operation of mine refrigeration equipment. The article ends with the statistical verification of the developed dependencies. For this purpose, for each model correlation coefficients and coefficients of determination were calculated, as well as absolute and relative deviations between the given values from the program REFPROP 7 (Lemmon et al., 2002) and the calculated ones. The results of these calculations have been contained in Tables 14 and 15.
Autorzy niniejszego artykułu zajęli się zagadnieniem modelowania właściwości (parametrów) termodynamicznych i termokinetycznych czynników chłodniczych. Znajomość tych parametrów jest niezbędna do projektowania urządzeń chłodniczych, ich analizy energetycznej, a także do porównaniu efektywności pracy chłodziarek powietrza wykorzystujących różne czynniki chłodnicze. Jednym ze stosowanych w górniczych sprężarkowych chłodziarkach powietrza czynnikiem chłodniczym jest R407C. Dla wymienionego czynnika chłodniczego opracowano 23 zależności określające jego parametry termodynamiczne i termokinetyczne w stanie cieczy nasyconej, w stanie pary nasyconej suchej, w stanie pary przegrzanej, w stanie cieczy przechłodzonej oraz w stanie pary mokrej. Utworzone wzory podano odpowiednio w tabelach: 2, 5, 8, 10 i 12. Należy zaznaczyć, że zakresy obowiązywania tych wzorów są szersze od zakresów zmian tego czynnika podczas normalnej pracy górniczych urządzeń chłodniczych. Artykuł kończy weryfikacja statystyczna utworzonych zależności. W tym celu dla każdego wzoru obliczono współczynniki korelacji, determinacji oraz odchyłki bezwzględne i względne między wartościami danymi z programu REFPROP 7 (Lemmon i in., 2002) a obliczonymi. Rezultaty tych obliczeń zamieszczono w tabelach 14 i 15.
Źródło:: Archives of Mining Sciences; 2017, 62, 1; 55-72
0860-7001
Pojawia się w:: Archives of Mining Sciences
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 94.

Tytuł:: Monazite Th-U-total Pb geochronology and P-T thermodynamic modelling in a revision of the HP-HT metamorphic record in granulites from Stary Gierałtów (NE Orlica-Śnieżnik Dome, SW Poland)
Autorzy:: Budzyń, B.
Jastrzębski, M.
Kozub-Budzyń, G. A.
Konečný, P.
Powiązania:: https://bibliotekanauki.pl/articles/2060006.pdf
Data publikacji:: 2015
Wydawca:: Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:: monazite
Th-U-total Pb dating
thermodynamic modelling
granulite
Orlica-Śnieżnik Dome
Bohemian Massif
Opis:: Thermodynamic modelling and monazite Th-U-total Pb dating via electron microprobe were used to improve the pressure, temperature and timing constraints of the HP-HT metamorphic record in granulites from Stary Gierałtów (NE Orlica-Śnieżnik Dome (OSD), SW Poland). The thermodynamic calculations constrained the P-T conditions to 20-22 kbar and ca. 920ºC in the felsic to intermediate granulites and 20-22 kbar and ca. 970ºC in the mafic granulite. These conditions are considered to closely represent the peak temperatures experienced by these rocks. In the intermediate granulite, the matrix monazite and monazite inclusions in garnet and allanite yielded an age of 349±2.5 Ma. An HP-HT metamorphic event with temperature conditions exceeding 900ºC, which are greater than the closure temperatures of most geochronometers, must have disturbed and completely reset the isotopic systems, including the Th-U-Pb system in the monazite. Consequently, this resetting prevented us from constraining the age of potential earlier metamorphic events or the igneous protolith. The 349±2.5 Ma age reflects the timing of the late-stage HP-HT event and cooling below 900ºC related to the initial exhumation of the granulites. A comparison of the new P-T-t constraints with previous data from the NE Orlica-Śnieżnik Dome indicates that the activation of the channels that exhumed the HP rocks to mid-crustal depths most likely initiated at ca. 350 Ma, and all the metamorphic rocks in the OSD likely shared a common Variscan evolution after ca. 340 Ma.
Źródło:: Geological Quarterly; 2015, 59, 4; 700--717
1641-7291
Pojawia się w:: Geological Quarterly
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 95.

Tytuł:: Warunki termodynamiczne podczas spawania drobnoziarnistej stali S960 MC
Thermodynamic conditions when welding fine-grained steel S960 MC
Autorzy:: Szczucka-Lasota, Bożena
Węgrzyn, Tomasz
Piwnik, Jan
Jurek, Adam
Kalwas, Jerzy
Wilczyński, Krzysztof Ireneusz
Powiązania:: https://bibliotekanauki.pl/articles/271124.pdf
Data publikacji:: 2020
Wydawca:: Centralny Ośrodek Badawczo-Rozwojowy Aparatury Badawczej i Dydaktycznej, COBRABiD
Tematy:: inżynieria lądowa
transport
środki transportu
warunki termodynamiczne
civil engineering
means of transport
thermodynamic conditions
Opis:: Nieustannie wrasta zapotrzebowanie na spajanie trudno-spawalnych stali wysokowytrzymałych stosowanych w inżynierii lądowej i w transporcie. Ważnym materiałem konstrukcyjnym w budowie środków transportu są stale drobnoziarniste z uwagi na ich dużą wytrzymałość na rozciąganie na poziomie 1250 MPa. Celem niniejszego artykułu było dobranie parametrów termodynamicznych w procesie spawania MAG trudno-spawalnej stali S960 MC. Stale drobnoziarniste, charakteryzują się wysoką wytrzymałością na rozciąganie i granicą plastyczności. Złącza z tych stali są trudnospawalne ze względu na dominującą strukturę martenzytyczną i skomplikowaną procedurę związaną z koniecznością ograniczenia zawartości wodoru w stopiwie. Postanowiono sprawdzić rolę podgrzewania wstępnego i temperatury warstw międzyściegowych na poprawność wykonanego złącza MAG konstrukcji o grubości 8 mm. Sprawdzono udarność złącza i oszacowano zawartość wodoru dyfundującego w stopiwie.
There is growing demand for bonding high-strength steels with a low level of weldability used in civil engineering and transport. Fine-grained steels are an important material for the construction of means of transport due to their high tensile strength of 1000 MPa. The aim of this article was to select thermodynamic parameters for MAG welding of low weldability S960 MC steel. Fine-grained steels demonstrate a high tensile strength and yield point. Joints made using these steels are difficult to weld due to the dominant martensitic structure and the complicated procedure needed to limit hydrogen in the weld. A decision was made to check the impact of preheating and the temperature of interpass layers on the correctness of a MAG joint in a structure 8 mm thick. The impact toughness of the joint has been checked and the content of diffusible hydrogen in the weld estimated.
Źródło:: Aparatura Badawcza i Dydaktyczna; 2020, 25, 2; 102-111
2392-1765
Pojawia się w:: Aparatura Badawcza i Dydaktyczna
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 96.

Tytuł:: Maximisation of Combined Cycle Power Plant Efficiency
Maksymalizacja sprawności elektrowni gazowo-parowych
Autorzy:: Kotowicz, J.
Job, M.
Brzęczek, M.
Powiązania:: https://bibliotekanauki.pl/articles/397508.pdf
Data publikacji:: 2015
Wydawca:: ENERGA
Tematy:: combined cycle power plant
turbine cooling
thermodynamic optimisation
elektrownia gazowo-parowa
chłodzenie turbiny
optymalizacja
Opis:: The paper presents concepts for increasing the efficiency of a modern combined cycle power plant. Improvement of gas turbine performance indicators as well as recovering heat from the air cooling the gas turbine’s flow system enable reaching gross electrical efficiencies of around 65%. Analyses for a wide range of compressor pressure ratios were performed. Operating characteristics were developed for the analysed combined cycle plant, for different types of open air cooling arrangements of the gas turbine’s expander: convective, transpiration and film.
W artykule przedstawiono koncepcje zwiększenia sprawności nowoczesnej elektrowni gazowo-parowej. Poprawa charakterystyk pracy turbiny gazowej oraz wykorzystanie ciepła powietrza chłodzącego układ przepływowy turbiny gazowej pozwalają na osiągnięcie sprawności elektrycznej brutto rzędu 65%. Analizy przeprowadzono w szerokim zakresie stopni sprężania w kompresorze. Sporządzono główne charakterystyki pracy analizowanego układu gazowo-parowego dla różnych typów chłodzenia otwartego powietrzem ekspandera turbiny gazowej: konwekcyjnego, transpiracyjnego oraz błonowego.
Źródło:: Acta Energetica; 2015, 4; 42-53
2300-3022
Pojawia się w:: Acta Energetica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 97.

Tytuł:: Oxygen Activity in Melts of Fe-C-Cr-Ni Based Alloys
Autorzy:: Záděra, A.
Dulava, M.
Pernica, V.
Kaňa, V.
Powiązania:: https://bibliotekanauki.pl/articles/381686.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: oxygen activity
polycomponent solution
thermodynamic equilibrium
activity coefficient
aktywność tlenu
równowaga termodynamiczna
współczynnik aktywności
Opis:: Oxygen is an element that is first purposely brought into the steel melt to remove some unwanted elements or to reduce their concentration (oxidation). In the made cast steel there is on the contrary necessary to reduce the oxygen content with the use of deoxidation to such a level in order to avoid a reaction with carbon with the formation of CO bubbles. Concentration of oxygen in steel before casting is given, in particular, by the manner of metallurgical processing and the used deoxidation process. Oxygen is found in molten steels both as chemically bound in the form of oxides and in the form of oxygen dissolved in the solution – the melt. Chemical composition of the melt strongly influences the activity of oxygen dissolved in the melt and further on the composition of oxidic inclusions forming in the melt during the reaction with oxygen. In the Fe-C-Cr-Ni based alloys in the reaction with oxygen greatly participates also chrome, whose products are often in solid state and they are the cause of forming such defects as e.g. oxidic films.
Źródło:: Archives of Foundry Engineering; 2016, 16, 4; 181-186
1897-3310
2299-2944
Pojawia się w:: Archives of Foundry Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 98.

Tytuł:: Obliczenia numeryczne i analiza wytrzymałości silnika Stirlinga typu alfa
Numerical calculations and strength analysis of the Stirling engine of alpha type
Autorzy:: Płoński, M.
Grzejda, R.
Powiązania:: https://bibliotekanauki.pl/articles/268670.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
Tematy:: kogeneracja
obieg termodynamiczny
silnik Stirlinga
mechanizm korbowy
cogeneration
thermodynamic cycle
Stirling engine
crank mechanism
Opis:: Przedstawiono model bryłowy i obliczenia silnika Stirlinga typu alfa. Scharakteryzowano podstawowe typy silników Stirlinga. Zaprezentowano model I rzędu (model Schmidta) obiegu termodynamicznego dla wybranego silnika, na podstawie którego dobrano warunki obciążenia dla zbudowanego modelu bryłowego tego silnika. Przeprowadzono statyczną analizę wytrzymałości mechanizmu roboczego silnika z korpusem dla trzech położeń wału korbowego z wykorzystaniem metody elementów skończonych. Przedstawiono wybrane wyniki badań numerycznych modelu mechanizmu roboczego silnika z korpusem w postaci mapy naprężeń zredukowanych wywołanych zadanym ciśnieniem czynnika roboczego. Na ich podstawie wykazano poprawność konstrukcji mechanizmu roboczego silnika i jego korpusu według przyjętego kryterium wytrzymałościowego.
The solid model and calculations of the Stirling engine of alpha type are presented. The basic types of single acting Stirling engines (called as: alpha, beta, gamma) are characterised. The first order model (Schmidt’s model) of the thermodynamic cycle for the selected engine is shown. On its basis, the loading conditions for the constructed solid model of this engine are chosen. Static analysis of the strength of the working mechanism of the engine and its body is carried out for three positions of the crankshaft (for the upper position of the piston in the cold cylinder, aberration of the crankshaft by 30 degrees from the upper position of the piston and aberration of the crankshaft by 90 degrees from the upper position of the piston). The calculations are made using the finite element method (FEM). Selected results of simulation studies of the FEMmodel of the working mechanism of the engine and its body in the form of reduced stress maps in the model under specified pressure of the working medium are presented. On their basis, the correctness of the structure of the modelled working mechanism of the engine and its body has been demonstrated according to the adopted strength criterion.
Źródło:: Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2018, 61; 65-68
1425-5766
2353-1290
Pojawia się w:: Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 99.

Tytuł:: Simultaneous synthesis-immobilization of nano ZnO on perlite for photocatalytic degradation of an azo dye in semi batch packed bed photoreactor
Autorzy:: Khani, A.
Sohrabi, M.R.
Powiązania:: https://bibliotekanauki.pl/articles/778943.pdf
Data publikacji:: 2012
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: Natural gas vehicle
driving range
compressed natural gas (CNG)
thermodynamic properties
CNG fuelling station
Opis:: A novel, simple and simultaneous synthesis-immobilization of nano ZnO on perlite (nZnO-P) as a photocatalyst for photocatalytic degradation of Acid orange 7 (AO7) in aqueous solution was investigated. The effect of operational parameters such as initial dye concentration, initial pH, flow rate, photocatalyst granule size, temperature and the kinetic of the removal of AO7 in terms of the Langmuir-Hinshelwood model in a designed semi batch packed bed photoreactor connected to an on-line sampling UV-Vis spectrophotometer was studied. The results showed that AO7 removal efficiency increased with nZnO-P using the designed setup and the proposed photocatalyst was more efficient than TiO2 as a standard catalyst. Our results confirmed the pseudo-first-order kinetics model. The values of the adsorption equilibrium constant, KAO7, the kinetic rate constant of surface reaction, kc, and the activation energy (Ea) were found to be 0.57 (mg.l-1)-1, 0.41 mg.l-1.min-1 and 11.44 kJ/mol, respectively.
Źródło:: Polish Journal of Chemical Technology; 2012, 14, 4; 69-76
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 100.

Tytuł:: The effect of important parameters on the natural gas vehicles driving range
Autorzy:: Farzaneh-Gord, M.
Rahbari, H.R.
Nikofard, H.
Powiązania:: https://bibliotekanauki.pl/articles/778945.pdf
Data publikacji:: 2012
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: Natural gas vehicle
driving range
compressed natural gas (CNG)
thermodynamic properties
CNG fuelling station
Opis:: One of the most important issues regarding Natural Gas Vehicles (NGVs) is the Driving Range, chich is defi ned as capability of a NGV to travel a certain distance after each refueling. The Driving Range is a serious obstacle in the development and growth of NGVs. Thus the necessity of studying the effects of various parameters on the Driving Range could be realized. It is found that the on-board storage capacity and the natural gas heating value have the greatest effect on the Driving Range. The charge mass of NGV cylinders is varied due to the natural gas composition and the fi nal in-cylinder values (temperature and pressure). Underfi lling of NGV cylinders, during charging operations, is a result of the elevated temperature which occurs in the NGV storage cylinder, due to compression and Rother processes could be overcome by applying extensive over-pressurization of the cylinder during the fuelling operation. Here, the effects of the most important parameters on the Driving Range have been investigated. The parameters are natural gas composition, engine effi ciency and fi nal NGV on-board in-cylinder temperature and pressure. It is found that, the composition has big effects on the Driving Range. The results also show that as fi nal in-cylinder pressure decreases (or temperature increases), the Driving Range will be increased.
Źródło:: Polish Journal of Chemical Technology; 2012, 14, 4; 61-68
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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