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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