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Tytuł:
Comparative evaluation of different techniques for herniorrhaphy in calves
Autorzy:
Fatima, A.
Arif Khan, M.
Aslam, S.
Ashraf, K.
Khalid Mahmood, A.
Asif, M.
Shah, S.
Hussain, N.
Powiązania:
https://bibliotekanauki.pl/articles/16539145.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
calves
mesh application
suture material
umbilical hernia
Opis:
Umbilical hernia is one of the most common problems in young calves. This problem occurs in dairy sector as well as in the local farmers. Present study was conducted to compare outcomes of four different techniques of herniorrhaphy. Twenty four young calves (n=24) were divided in 4 groups (A, B, C, and D) which underwent four different surgical techniques. Group A underwent vicryl plus suture material and pants-over-west technique, Group B underwent mesh application with Dexon suture material by using simple interrupted suture pattern, Group C underwent closed method with Nylon No. 3 suture material by using vertical mattress suture pattern and Group D underwent clamp application method with Silk No. 2 suture material by using simple interrupted suture pattern. The result showed that mesh application method was comparatively better with respect to feed intake, body weight gain and healing time. There was no reoccurrence with non-significant hematological changes (p≤0.05). It is concluded that mesh application method is safer than other three techniques and there are no systemic effects of this surgical intervention on calves’ health.
Źródło:
Polish Journal of Veterinary Sciences; 2022, 25, 2; 207-212
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of a linear quadratic regulator based on genetic model reference adaptive control
Autorzy:
Abdullah, Abdullah I.
Mahmood, Ali.
Thanoon, Mohammad A.
Powiązania:
https://bibliotekanauki.pl/articles/27314263.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
model reference adaptive control
gradient approach
Linear Quadratic Regulator
genetic algorithm
Opis:
The conventional control system is a controller that controls or regulates the dynamics of any other process. From time to time, a conventional control system may not behave appropriately online; this is because of many factors like a variation in the dynamics of the process itself, unexpected changes in the environment, or even undefined parameters of the system model. To overcome this problem, we have designed and implemented an adaptive controller. This paper discusses the design of a controller for a ball and beam system with Genetic Model Reference Adaptive Control (GMRAC) for an adaptive mechanism with the MIT rule. Parameter adjustment (selection) should occur using optimization methods to obtain an optimal performance, so the genetic algorithm (GA) will be used as an optimization method to obtain the optimum values for these parameters. The Linear Quadratic Regulator (LQR) controller will be used as it is one of the most popular controllers. The performance of the proposed controller with the ball and beam system will be carried out with MATLAB Simulink in order to evaluate its effectiveness. The results show satisfactory performance where the position of the ball tracks the desired model reference.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2022, 16, 3; 75--81
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigating the effect of insoluble additives type on the drag reduction performance in a crude oil turbulent flow system
Autorzy:
Mahmood, Wafaa Kamil
Abdulbari, Hayder A.
Laft, Asaad H.
Powiązania:
https://bibliotekanauki.pl/articles/2142862.pdf
Data publikacji:
2022
Wydawca:
Centrum Badań i Innowacji Pro-Akademia
Tematy:
drag reduction
turbulence
insoluble additives
crude oil
powder
redukcja oporu
turbulencja
dodatki nierozpuszczalne
ropa naftowa
proszek
Opis:
In the present work, the effect of three insoluble additives densities on reducing the drag of crude oil was investigated. The objective of the present work is to evaluate the effect of the insoluble additive’s densities on their drag reduction efficiency in hydrocarbon flow medium. Three powders with different densities are chosen, namely carbon powder, glass powder, and copper powder, with a density of 1710 kg/m3 , 2550 kg/m3 , and 8950 kg/m3 , respectively. The turbulence flow environment was created in a custom-made rotating disc apparatus with a maximum rotation speed of 300 rpm. To evaluate the effect of the powder density, the particle's size was chosen to be 100 µm. All the solutions were tested at the exact operating conditions with a rotation speed ranging between 200 to 2200 rpm. The experimental results showed a clear effect of the powder density on the drag reduction performance. The glass powders showed the highest drag reduction effect, while the copper and carbon powders were lower. The effect of the degree of turbulence on the drag reduction performance of the powders was clear, where the interaction between the powders and the turbulence structures (eddies) governed the turbulence-suppression efficiency of the additives.
Źródło:
Acta Innovations; 2022, 43; 44-53
2300-5599
Pojawia się w:
Acta Innovations
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seroprevalence, associated risk factors and clinico-pathological studies of buffalopox disease in various regions of Punjab province, Pakistan
Autorzy:
Usmani, M.W.
Rizvi, F.
Khatoon, A.
Mahmood, M.S.
Powiązania:
https://bibliotekanauki.pl/articles/16539103.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
seropositive
single radial hemolysis
scab samples
PCR
C18L gene
leukocytes
Opis:
Buffalopox (BPX) is a highly contagious disease that causes high morbidity and production losses in buffaloes. During this study, seroprevalence, effect of various associated risk factors, and pathological studies of BPX were recorded in the Punjab province. A total of 97 blood samples and 63 scabs were collected from clinically pox suspected buffaloes. Serum was harvested to perform single radial hemolysis to assess the seroprevalence, and scabs were subjected to PCR for BPX virus confirmation. Results revealed that, animal demographics and environmental associated factors showed significant effect (p<0.05,1<R2>0) on BPX occurrence. The overall BPX seroprevalence was recorded 4.18% in the Punjab province. The BPX was recorded 5.48% in Nili Ravi breed during winter (7.42%), aged 5-7 years (7.46%) under loose housing (5.51%) in the Faisalabad region (8.03%). Further, BPX was 5.37% in pregnant, 6.86% pregnant milking buffaloes during the 3rd lactation period (7.28%) in dairy herds (5.20%). The BPX was 5.22% in non-vaccinated buffaloes where multiple animals were reared together (4.99%) in the herds having 21-30 total number of animals. A total of 49 scab samples were found positive for the BPX virus via PCR with C18L gene amplification. Grossly, inflammatory lesions with pits in the center and wart-like nodules were seen on teats and udder of buffaloes. Increased leukocytes, especially neutrophils and lymphocytes, were seen in the blood of the infected animals. These results provide a broader window to understand the effect of associated risk factors, strengthen the diagnostic aid, and to contain the current spread of BPX in Pakistan to safeguard large ruminant-based livelihood.
Źródło:
Polish Journal of Veterinary Sciences; 2022, 25, 1; 137-147
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Arsenic removal through bio sand filter using different bio-adsorbents
Autorzy:
Keerio, Ghulam S.
Keerio, Hareef A.
Ibuphoto, Khalil A.
Laghari, Mahmood
Panhwar, Sallahuddin
Talpur, Mashooque A.
Powiązania:
https://bibliotekanauki.pl/articles/1844385.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
arsenic
banana peel
bio-adsorbent
bio-sand filter
biochar
rice-husk
water treatment
Opis:
Arsenic is one of the most harmful pollutants in groundwater. In this paper, the Nepali bio sand filter (BSF) was modified with different bio-adsorbents, and proved to be an efficient method for arsenic removal from groundwater. Three different bio-adsorbents were used to modify the Nepali BSF. Iron nails and biochar BSF, ~96% and ~93% arsenic removal was achieved, within the range of WHO guidelines. In iron nails, BSF and biochar BSF ~15 dm3∙h–1 arsenic content water was treated. In the other two BSFs, rice-husk and banana peel were used, the arsenic removal efficiency was ~83% of both BSFs. Furthermore, the efficiency of rice-husk and banana peel BSFs can be increased by increasing the surface area of the adsorbent or by reducing the flow rate.
Źródło:
Journal of Water and Land Development; 2021, 48; 11-15
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation of convective heat transfer of single wall carbon nanotube nanofluid laminar flow inside a circular tube
Autorzy:
Saeed, Farqad Rasheed
Jasim, Marwah A.
Mahmood, Natheer B.
Jaffar, Zahraa M.
Powiązania:
https://bibliotekanauki.pl/articles/1845470.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
convective heat transfer
reynolds number
nanofluid
single
wall
carbon
nanotube
SWCNT
laminar flow
Opis:
This study presents the behavior of a single wall carbon nanotube (SWCNT)/water nanofluid for convective laminar flow inside a straight circular pipe heated by a constant heat flux. Five volume fractions of SWCNT were used to investigate their effect on the heat transfer coefficient, Nusselt number, temperature distribution and velocity field in comparison with pure water flow. One model for each property was tested to calculate the effective thermal conductivity, effective dynamic viscosity, and effective specific heat of the SWCNT/water mixture. The models were extracted from experimental data of a previous work. The outcomes indicate that the rheological behavior of SWCNT introduces a special effect on the SWCNT/water properties, which vary with SWCNT volume fraction. The results show an improvement in the heat transfer coefficient with increasing volume fraction of nanoparticles. The velocity of SWCNT/water nanofluid increased by adding SWCNT nanoparticles, and the maximum increase was registered at 0.05% SWCNT volume fraction. The mixture temperature is increased with the axial distance of the pipe but a reduction in temperature distribution is observed with the increasing SWCNT volume fraction, which reflects the effect of thermophysical properties of the mixture.
Źródło:
Archives of Thermodynamics; 2021, 42, 2; 103-119
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Review of mechanical vapour compression refrigeration system part 2: performance challenge
Autorzy:
Mahmood, R. A.
Ali, O. M.
Al-Janabi, A.
Al-Doori, G.
Noor, M. M.
Powiązania:
https://bibliotekanauki.pl/articles/2106451.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
para
układ chłodniczy
współczynnik wydajności
vapour compression
refrigeration system
cycle
coefficient of performance COP
Opis:
Reducing energy consumption and providing high performance for a vapour compression refrigeration system are big challenges that need more attention and investigation. This paper provides an extensive review of experimental and theoretical studies to present the vapour compression refrigeration system and its modifications that can be used to improve system’s performance and reduce its energy consumption. This paper also presents the challenges that can be considered as a gab of research for the future works and investigations. Cooling capacity, refrigerant effect, energy consumption can be improved by using vapour injection technique, natural working fluid, and heat exchanger. Based on the outcome of this paper, vapour injection technique using natural refrigerant such as water can provide ultimate friendly refrigeration system. Future vision for the vapour compression refrigeration system and its new design technique using Computational Fluid Dynamic (CFD) is also considered and presented.
Źródło:
International Journal of Applied Mechanics and Engineering; 2021, 26, 3; 119--130
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spiro-cyclotriphosphazene with three functional end groups: synthesis and structural characterization of new polycyclotriphosphazenes with Schiff-base groups
Spiro-cyklotrifosfazen z trzema funkcyjnymi grupami końcowymi: synteza i charakterystyka struktury nowych policyklotrifosfazenów z grupami zasad Schiffa
Autorzy:
Al-Shukri, Salah Mahdi
Mahmood, Ayad Tarik
Al Hanbali, Othman A.
Powiązania:
https://bibliotekanauki.pl/articles/1790060.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
Tematy:
spirocyclotriphosphazene
polycyclophosphazene
poly(schiff-base)
thermal stability
flame retardancy
spirocyklotrifosfazen
policyklofosfazen
poli(zasada Schiffa)
stabilność termiczna
ognioodporność
Opis:
A new tris-spiro-(3,4-dioxybenzaldehyde)cyclotriphosphazene [PNCHO] was synthesized from the condensation of hexachlorocyclotriphosphazene with 3,4-dihydroxybenzaldehyde in the presence of strong base. Further reaction of the trialdehydic cyclotriphosphazene based molecules [PNCHO] with three different dianilines (benzidine, 4,4’-methylenedianiline and 4,4′-Sulfonyldianiline) resulted in creation of a new poly(tris-spiro-3,4-dioxbenzene)cyclotriphosphazenes with Schiff-base groups [PNSB1-3]. The structures of [PNCHO] and the polycyclotriphosphazenes-schiff base derivatives were characterized by means of FTIR, 1H, 13C NMR and C.H.N elemental analysis. Differential scanning calorimetery (DSC) revealed a relatively high glass transition temperature (135−175°C) of obtained polymers. Thermal gravimetric analysis (TGA) exhibited their good thermal stability (up to 375°C). The char yield was about 36–42% at 700°C. All polymers were self-extinguishable as the LOI (Limiting Oxygen Index) values were above 26% and this meets with the V-0 and V-1, classification (UL-94). No fumes, soot, or toxic gases emission were observed during burning. The polymers obtained can be used as environmentally friendly, flame-retardant materials.
Nowy tris-spiro-(3,4-dioksybenzaldehydo)cyklotrifosfazen [PNCHO] zsyntetyzowano w procesie kondensacji heksachlorocyklotrifosfazenu z 3,4-dihydroksybenzaldehydem w obecności silnej zasady. W wyniku reakcji trialdehydo cyklotrifosfazenów z trzema różnymi dianilinami (benzydyna, 4,4’-metylenodianilina i 4,4’-sulfonylodianilina) otrzymano poli(tris-spiro-3,4-dioksabenzeno)cyklotrifosfazeny z zasadami Schiffa [PNSB1-3]. PNCHO i pochodne policyklotrifosfazen-zasady Schiffa scharakteryzowano za pomocą analizy elementarnej (C, H, N), FTIR, 1H, 13C NMR. Metodą różnicowej kalorymetrii skaningowej (DSC) wykazano wysoką temperaturę zeszklenia (135−175°C) otrzymanych polimerów. Metodą analizy termograwimetrycznej (TGA) potwierdzono ich dobrą stabilność termiczną (do 375°C). Stopień zwęglenia po spaleniu wynosił w temp. 700°C ok. 36–42%. Wszystkie polimery były samogasnące, ponieważ wartości LOI (Limiting Oxygen Index) przekraczały 26%, co odpowiada klasie palności V-0 i V-1 (UL-94). Podczas spalania nie zaobserwowano emisji oparów, sadzy ani toksycznych gazów. Otrzymane polimery mogą znaleźć zastosowanie jako przyjazne dla środowiska materiały trudnopalne.
Źródło:
Polimery; 2021, 66, 6; 341--349
0032-2725
Pojawia się w:
Polimery
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Buckling and bending properties of aluminium plate with multiple cracks
Autorzy:
Mohmmed, J. H.
Mahmood, N. Y.
Ali, M.
Zainulabdeen, A. A.
Powiązania:
https://bibliotekanauki.pl/articles/1818485.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
buckling stability
bending strength
crack
aluminium plate
ANSYS package
stabilność wyboczeniowa
wytrzymałość na zginanie
pęknięcie
płyta aluminiowa
pakiet ANSYS
Opis:
Purpose: In this paper, the bending strength and buckling stability of (AA 7075-T6) aluminium plate weakened by many transverse cracks, which located at different positions, subjected to concentrated loads applied at the ends were analysed. Design/methodology/approach: Numerical modelling and calculation by the finite element method (ANSYS Package), for the critical load of bending and compression panel were estimated. Findings: It found that the variation of the critical stress in bending and buckling is proportional to the crack conditions (no. of crack and location). In general, the critical load in bending and buckling decreases with increasing the crack number in structure. Research limitations/implications: For both bending and buckling, two transverse cracks on one face of plate is more stable than two transverse cracks on opposite faces. Practical implications: In addition, many experimental tests were carried out by using an INSTRON test machine to obtain the buckling critical loads, where the experimental results were compared with the ones of the finite element method. Furthermore, bending strength was calculated theoretically for the cracked panel. Originality/value: Comparison between the experimental and numerical (FE based model) data and between the theoretical and nu-merical (FE based model) data for buckling and bending strength respectively indicate the precise and the simplicity of the developed models to determine the critical loads in such cases.
Źródło:
Archives of Materials Science and Engineering; 2020, 106, 2; 49--58
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First principle analysis of electronic, optical and thermoelectric characteristics of XBiO3 (X = Al, Ga, In) perovskites
Autorzy:
Mahmood, Q.
Rouf, S. A.
Algrafy, E.
Murtaza, G.
Ramay, S. M.
Mahmood, A.
Powiązania:
https://bibliotekanauki.pl/articles/1818225.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
density functional theory
structural stability
optoelectronics
thermoelectric applications
indirect band gap semiconductors
Opis:
The perovskites XBiO3 (X = Al, Ga, In) have been studied in terms of mechanical, optical and thermoelectric behavior for energy harvesting application. Density functional theory is applied to study electronic, optical and thermoelectric properties of the studied materials. Structural, mechanical and thermodynamic stabilities are confirmed from the tolerance factor, Born mechanical stability and formation energy/specific heat capacity. Poisson and Plough ratios show the studied materials are ductile and have ability to withstand pressure. Band structure analysis shows the indirect band gap 3.0/2.1/1.0 eV for ABO/GBO/IBO. A complete set of optical spectra is reported by dielectric constants, refractive index, optical conduction, absorption of light and optical loss energy. Shifting of maximum absorption band to visible region increases the potential of perovskites XBiO3. Transport characteristics are also investigated by electrical conductivity, Seebeck coefficient and figure of merit.
Źródło:
Opto-Electronics Review; 2020, 28, 1; 8--14
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameters optimization of MAG welding for enhancing the mechanical properties and buckling behaviour of welded steel
Autorzy:
Alwan, A. H.
Mahmood, N. Y.
Powiązania:
https://bibliotekanauki.pl/articles/368428.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
MAG welding parameters
critical buckling load
Taguchi method
ANOVA
optimization
spawanie MAG
parametry spawania
metoda Taguchi
optymalizacja
Opis:
Purpose: The influence of metal active gas welding variables, including current, wire feeding speed and gas flow rate on the ultimate tensile strength and critical buckling load of steel (St.24) and the optimized welding conditions were discussed. Design/methodology/approach: The experimental steps are firstly designing the experiments, secondly conducting the mechanical tests, thirdly analysing the results through Minitab 16 and finally determining the optimum welding parameters. Confirmation tests of the optimized variables were validated. Findings: ANOVA approach manifested that the significant effect of welding variable on the tensile strength was the gas flow rate, while the current was on the critical buckling load. The results are confirmed and given the optimum values. Research limitations/implications: The influence of MAG welding variables (current, wire feeding speed and gas flow rate) on the tensile and buckling strengths of steel will be investigated in order to avoid the failure of many welded assemblies in the structures due to the buckling, in addition to reduce the requirement of long time and high cost to produce such assemblies. Therefore, it is necessary to find a solution to encounter the difficulties in their welding process. Practical implications: The major challenge was how to reduce the time and cost beside gaining the optimum properties through the designed experiments. Originality/value: The results may be helpful to design any welded joints in machine frames, structural steel connections and crane structures at the optimum condition.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2020, 99, 1; 5-13
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
USE OF GLUTARIC ACID TO IMPROVE THE SOLUBILITY AND DISSOLUTION PROFILE OF GLIPIZIDE THROUGH PHARMACEUTICAL COCRYSTALLIZATION
Autorzy:
Batool, Fakhra
Ahmad, Mahmood
Minhas, Muhammad U.
Khalid, Qandeel
Idrees, Hafiz A.
Khan, Fahad M.
Powiązania:
https://bibliotekanauki.pl/articles/895470.pdf
Data publikacji:
2019-02-28
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
FTIR
SEM
PXRD
thermal analysis
glipizide
glutaric acid
Opis:
The purpose of current study was to improve the solubility and dissolution profile of BCS class-II drug Glipizide using glutaric acid as a coformer via various cocrystalization techniques i.e., dry grinding, liquid assisted grinding, slurry and solvent evaporation. Fourier Transform Infrared Spectroscopy (FTIR) was performed to determine the interaction between components of glipizide-glutaric acid (GPZ-GLU) cocrystals. Powder X-ray Diffraction (PXRD) studies confirmed the crystalline nature of formulated cocrystals. Scanning Electron Microscopy (SEM) revealed cylindrical to rectangular shape of cocrystals. Flow properties of GPZ-GLU cocrystals were evaluated by micromeritics analysis. Size and surface morphology was determined by zeta sizer analysis and optical microscopy. Differential scanning calorimetry (DSC) and Thermogravimetric (TGA) analysis were performed to determine the melting points as well as thermal stability of pure components and formulated GPZ-GLU cocrystals. In-vitro drug release studies were carried out using dissolution apparatus-II. GPZ-GLU cocrystals showed higher drug release at pH 6.8 as compared to pH 1.2. However, percent drug release of optimum formulations at pH 6.8 was determined as; 24%-92.2% (F3) and 12.0%-93.5% (F7). Solubility studies revealed improved solubility as compared to pure drug in water i.e., 53 folds and 54.27 folds from F3 and F7 cocrystals, respectively. Finally it was concluded that glutaric acid has improved the solubility and dissolution profile of glipizide. However, many cocrystal formers have been reported in literature that can be used to enhance the physicochemical properties as well as bioavailability of poorly soluble drugs via cocrystalization technique.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 1; 103-114
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Under Pressure DFT Investigations on Optical and Electronic Properties of PbZrO₃
Autorzy:
Nazir, G.
Tariq, Saad
Afaq, A.
Mahmood, Q.
Saad, S.
Mahmood, A.
Tariq, Samar
Powiązania:
https://bibliotekanauki.pl/articles/1030608.pdf
Data publikacji:
2018-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
density functional theory
optical properties
electronic structure
high pressure
Opis:
In this article, density functional theory has been used to investigate the structural and optoelectronic properties of PbZrO₃ (PZO) under pressure from 0 to 350 GPa. In order to achieve ground state structural stability, generalized gradient approximations has been utilized. By studying electronic properties, indirect band-gap nature of PZO appears to change at 15 GPa to direct band-gap. Optical analysis include under pressure responses of real and imaginary parts of dielectric function, optical conductivity, optical absorption coefficient, energy loss function, refractive index, reflectivity and extinction coefficient. Most of the results have been found to be consistent with literature. Study reveals that static dielectric constant and band-gap are in accordance with the Penn model which validates our computed results. Moreover, static dielectric constant and static refractive index directly increases with pressure. Material preserves its positive value of refractive index at all pressures and therefore, it is not a negative index metamaterial. Plasma frequency increases directly with pressure that destabilize the under study material. Our results could be very useful for developing novel optoelectronic devices based on PZO suitable to work under extreme conditions.
Źródło:
Acta Physica Polonica A; 2018, 133, 1; 105-113
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of micronutrients (Cu, Zn, Mn, and Fe) on the growth of Spathoglottis plicata plantlets
Autorzy:
Yasin, Z.A.M.
Mahmood, M.
Shaharudiin, N.A.
Powiązania:
https://bibliotekanauki.pl/articles/79811.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2017, 98, 1
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and Theoretical Investigation to Study the Molecular Structure, Electronic Properties, UV–Vis Spectra of Coumarin 102
Autorzy:
Mohi, Ali T.
Abood, Tareq H.
Hadi, Hasan A.
Karim, Mahmood S.
Mutlik, Falah A-H.
Alwan, Tariq J.
Powiązania:
https://bibliotekanauki.pl/articles/1178533.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
DFT
Ionization potential
TDDFT
electron affinity
energy gap and UV spectra
Opis:
In this work, we study the structure, electronic properties and electronic spectra of Coumarin 102 (C102) dissolved in ethanol as an experimental-theoretical investigation. The various properties of the ground and excited electronic states of coumarins 102 using density functional theory (DFT) and time-dependent density functional theory (TDDFT) was calculated by the B3LYP density functional model with 6-31G(d,p) basis set by Gaussian 09 W program. Spectral characteristics of coumarin 102 have been probed into by methods of experimental UV-visible, and quantum chemistry. The UV spectrum was measured in Ethanol. The optimized structures, total energies, electronic states (HOMO- LUMO), energy gap, ionization potentials, electron affinities, chemical potential, global hardness, softness, global electrophilictity, dipole moment and electrostatic potential was calculated. were calculated. We find good agreement between experimental data of UV spectrum and TDDFT excitation energies.
Źródło:
World Scientific News; 2017, 70, 2; 216-229
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 24

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