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Structural, electronic, and optical properties of ZnO_(1-x)Se_x alloys using first-principles calculations

Chinese Physics B 2013年第8期22卷 581-588页

作者： muhammad Rashid Fayyaz Hussain muhammad Imran S A Ahmad N A Noor m u Sohaib S m Alay-e-Abbas Department of Physics Simulation Laboratory the Islamia University of Bahawalpur63100 Pakistan Department of Physics University of the Punjab Quaid-e-Azam Campus54590 Lahore Pakistan Lahore Development Authority 54590 Lahore Pakistan Department of Physics GC University FaisalabadAllama Iqbal Road Faisalabad 38000 Pakistan

The structural, electronic, and optical properties of binary ZnO, ZnSe compounds, and their ternary ZnOl_xSex alloys are computed using the accurate full potential linearized augmented plane wave plus local orbital （FP-LAPW ＋ lo） method in the rocksalt （B 1） and zincblende （B3） crystallographic phases. The electronic band structures, fundamental energy band gaps, and densities of states for ZnO1_xSex are evaluated in the range 0 〈 x 〈 1 using Wu-Cohen （WC） generalized gradient approximation （GGA） for the exchange-correlation potential. Our calculated results of lattice parameters and bulk modulus reveal a nonlinear variation for pseudo-binary and their ternary alloys in both phases and show a considerable deviation from Vegard＇s law. It is observed that the predicted lattice parameter and bulk modulus are in good agreement with the available experimental and theoretical data. We establish that the composition dependence of band gap is semi-metallic in B1 phase, while a direct band gap is observed in B3 phase. The calculated density of states is described by taking into account the contribution of Zn 3d, O 2p, and Se 4s, and the optical properties are studied in terms of dielectric functions, refractive index, reflectivity, and energy loss function for the B3 phase and are compared with the available experimental data.

关键词： density functional theory alloys structural electronic optical properties

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Physical aspects of anisotropic compact stars in f(T,■) gravity with off diagonal tetrad

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Chinese Physics C 2021年第8期 195-210页

作者： m.Zubair Allah Ditta G.Abbas Rabia saleem Department of mathematics COMSATS University Islamabad Department of mathematics The Islamia University of Bahawalpur

This study addresses the formation of anisotropic compact star models in the background of f(T,■)gravity(where T and ■ represent the torsion and trace of the energy momentum tensor,respectively).f(T,■) gravity is an extension of the f(T) theory,and it allows a general non-minimal coupling between T and ■.In this setup,we apply Krori and Barua’s solution to the static spacetime with the components ξ=Br~2+c and Ψ=Ar~*** develop viable solutions,we select a well-known model f(T,■)=aT~m+β■+φ(where α and β are coupling parameters,and φ indicates the cosmological constant).We adopt the conventional matching of interior and exterior space time to evaluate the unknowns,which are employed in the stellar *** present a comprehensive discussion on the stellar properties to elaborate the anisotropic nature of compact stars corresponding to well-known models:PSRJ1416-2230,4u1608-52,CenX-3,EX01785-248,and *** physical analysis,it is observed that the solution of compact spheres satisfy the acceptability criteria,and its models behave optimally and depict stability and consistency,in accordance with f(T,■) gravity.

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Computed tomography overestimation of esophageal tumor length: Implications for radiotherapy planning

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World Journal of Gastrointestinal Oncology 2010年第4期2卷 197-204页

作者： Karim Sillah Luke R Williams Hans-ulrich Laasch Azeem saleem Gillian Watkins Susan A Pritchard Patricia m Price Catharine m West Ian m Welch Department of Gastrointestinal Surgery University Hospital of South Manchester NHS Foundation TrustSouthmoor RoadManchester M23 9LTUnited Kingdom School of Cancer&Enabling Sciences University of ManchesterChristie HospitalWilmslow RoadManchester M20 4BXUnited Kingdom Department of Radiology University Hospital of South Manchester NHS Foundation TrustSouthmoor RoadManchester M23 9LTUnited Kingdom Department of Radiology The Christie NHS Foundation TrustWilmslow RoadManchester M20 4BXUnited Kingdom Department of Histopathology University Hospital of South Manchester NHS Foundation TrustSouthmoor RoadManchester M23 9LTUnited Kingdom

AIm:To assess the relationship between preoperative computed tomography(CT)and postoperative pathological measurements of esophageal tumor length and the prognostic significance of CT tumor length ***:A retrospective study was carried out in 56 patients who underwent curative *** lengths were measured on the immediate preoperative CT and on the post-operative resection ***-and intra-observer variations in CT measurements were *** data were ***:There was a weak correlation between CT and pathological tumor length(r=0.30,P=0.025).CT lengths were longer than pathological lengths in 68%(38/56)of patients with a mean difference of 1.67 cm(95%CI:1.18-2.97).The mean difference in measurements by two radiologists was 0.39 cm(95% CI:-0.59-1.44).The mean difference between repeat CT measured tumor length(intra-observer variation) were 0.04 cm(95%CI:-0.59-0.66)and 0.47 cm (95%CI:-0.53-1.47).When stratified,patients not receiving neoadjuvant chemotherapy showed a strong correlation between CT and pathological tumor length(r =0.69,P=0.0014,n=37)than patients that did(r= 0.13,P=0.43,n=19).median survival with CT tumor length>5.6 cm was poorer than with smaller tumors,but the difference was not statistically ***:Esophageal tumor length assessed using CT does not reflect pathological tumor extent and should not be the only modality used for management decisions,particularly for planning radiotherapy.

关键词： Computed tomography Esophageal cancer Radiotherapy

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Prediction of moment of inertia of rotating nuclei

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Chinese Physics C 2020年第11期44卷 179-188页

作者： mohd Kh.m.Abu El Sheikh A.A.Okhunov H.Abu Kassim m.u.Khandaker Department of Physics University of Malaya50603 Kuala LumpurMalaysia Department of Science in Engineering International Islamic University Malaya50728 Kuala LumpurMalaysia Namangan Institute of Engineering and Technology 160000 NamanganUzbekistan Centre for Biomedical Physics School of Healthcare and Medical SciencesSunway University47500 Bandar SunwayMalaysia

In this study,the mathematical expression formulated by Bohr for the moment of inertia of even-even nuclei based on the hydrodynamical model is *** modification pertains to the kinetic energy of the surface oscillations,including the second and third terms of the R-expansion as well as the first term,which had already been modified by ***,this work can be considered a continuation and support of Bohr's hydrodynamic *** procedure yields a Bohr formula to be multiplied by a factor that depends on the deformation ***'s(modified)formula is examined by applying it on axially symmetric even-even nuclei with atomic masses ranging between 150 and 190 as well as on some triaxial symmetry *** this paper,the modification of Bohr's formula is discussed,including information about the stability of this modification and the second and third terms of the R-expansion in Bohr's *** results of the calculation are compared with the experimental data and Bohr's results recorded *** results obtained are in good agreement with experimental data,with a ratio of approximately 0.7,and are better than those of the unmodified ones.

关键词： moment of inertia hydrodynamical model irrotational motion

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Investigation of soliton solutions with different wave structures to the(2+1)-dimensional Heisenberg ferromagnetic spin chain equation

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Communications in Theoretical Physics 2020年第3期72卷 7-13页

作者： m S Osman K u Tariq Ahmet Bekir A Elmoasry Nasser S Elazab m Younis mahmoud Abdel-Aty Department of mathematics Faculty of ScienceCairo UniversityGizaEgypt Department of mathematics Faculty of Applied ScienceUmm Alqura UniversityMakkah 21955Saudi Arabia School of mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Department of mathematics Mirpur University of Science and TechnologyMirpur(AJK)10250Pakistan Neighbourhood of Akcaglan Imarli StreetNumber:28/426030EskisehirTurkey mathematics department College of ScienceMajmaah UniversitySaudi Arabia Punjab university College of Information Technology University of the PunjabLahore 54590Pakistan Department of mathematics Faculty of ScienceSohag UniversitySohagEgypt Applied Science university Bahrain

The principal objective of this article is to construct new and further exact soliton solutions of the(2+1)-dimensional Heisenberg ferromagnetic spin chain equation which investigates the nonlinear dynamics of magnets and explains their ordering in ferromagnetic *** solutions are exerted via the new extended FAN sub-equation *** successfully obtain dark,bright,combined bright-dark,combined dark-singular,periodic,periodic singular,and elliptic wave solutions to this equation which are interesting classes of nonlinear excitation presenting spin dynamics in classical and semi-classical continuum Heisenberg systems.3D figures are illustrated under an appropriate selection of *** applied technique is suitable to be used in gaining the exact solutions of most nonlinear partial/fractional differential equations which appear in complex phenomena.

关键词： soliton solutions Heisenberg ferromagnetic equation FAN sub-equation method

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Instanton effects on the heavy-quark static potential

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Chinese Physics C 2017年第8期41卷 19-30页

作者： u.T.Yakhshiev Hyun-Chul Kim B.Turimov m.m.musakhanov Emiko Hiyama Department of Physics Inha UniversityIncheon 22212Republic of Korea RIKEN Nishina Center RIKEN2-1 Hirosawa351-0115 SaitamaJapan School of Physics Korea Institute for Advanced Study(KIAS)Seoul 02455Republic of Korea Theoretical Physics Department National University of UzbekistanTashkent-174Uzbekistan

We investigate instanton effects on the heavy-quark potential, including its spin-dependent part, based on the instanton liquid model. Starting with the central potential derived from the instanton vacuum, we obtain the spin-dependent part of the heavy-quark potential. We discuss the results of the heavy-quark potential from the instanton vacuum. Finally, we solve the nonrelativistic two-body problem, associated with the heavy-quark potential from the instanton vacuum. The instanton effects on the quarkonia spectra are marginal but are required for quantitative description of the spectra.

关键词： instanton-induced interactions heavy-quark potential quarkonia

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Numerical investigations of arc behaviour in gas metal arc welding using ANSYS CFX

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Frontiers of materials Science 2011年第2期5卷 98-108页

作者： m. SCHNICK u. FuESSEL m. HERTEL A. SPILLE-KOHOFF A. B. muRPHY Institute of Surface and manufacturing Technology Technische Universitat Dresden Dresden Germany CFX Berlin Software GmBH Berlin Germany CSIRO materials Science and Engineering Lindfield NSW 2070 Australia

Current numerical models of gas metal arc welding（GmAW）are trying to combine magnetohydrodynamics （mRD） models of the arc and voiume of fluid （VoF） models of metal transfer They neglect vaporization and assume an argon atmosphere for the arc region, as it is common practice for models of gas tungsten arc welding, These models predict temperatures above 20 000K anda temperature distribution similar to tungsten inert gas （TIG） arcs： However. current spectroscopic temperature measuretemperatures. In contrast to TIG arcs temperature distrbution. The paper vapour and which is in a yery good res, Futhermore; the model is abile to predict the local central minimum in the radial temperature and the radial electric current density distributions for the first time. The axially symmetric model of the welding torch, the work piece, the wire and the arc （fluid domain） implements mHD as well as turbulent mixing and thermal demixing of metal vapour in argon. The mass fraction of iron vapour obtained from the simulation shows an accumulation in the arc core and another accumulation on the fringes of the arc at 2000 to 5000 K. The demixing effects lead to very low concentrations of iron between these two regions. Sensitive analyses demonstrate the influence of the transport and radiation properties of metal vapour, and the evaporation rate relative to the wire feed. Finally the model predictions are compared with the measuring results of Zielihska et al.

关键词： arc welding numericai simulation GmAW, ANSYS CFX

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Slip flow of maxwell viscoelasticity-based micropolar nanoparticles with porous medium: a numerical study

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Applied mathematics and mechanics(English Edition) 2019年第9期40卷 1255-1268页

作者： H. WAQAS m. ImRAN S. u. KHAN S. A. SHEHZAD m. A. mERAJ Department of mathematics Government College University Faisalabad Faisalabad 38000 Pakistan Department of mathematics COMSATS University Islamabad Sahiwal 57000 Pakistan

This article presents the mass and heat transport aspects in viscoelastic nanofluid flows under the presence of velocity slip conditions. To explore the nonNewtonian behavior, a maxwell viscoelasticity-based micropolar is considered. moreover, a porous medium saturates the stretching sheet. A set of similarity variables is introduced to derive the dimensionless ordinary differential equations of velocity, concentration, and temperature profiles. The numerical solution is computed by using the mATLAB bvp4c package. The salient flow features of velocity, concentration, and temperature profiles are described and discussed through various graphs. It is observed that with an increase in the slip parameter, the micro-rotation velocity also increases. The temperature of nanoparticles gets maximum values by varying the viscoelastic parameter and the porosity parameter while an opposite trend is noted for the micro-rotation parameter. The local Nusselt number and the local Sherwood number increase by increasing the viscoelastic parameter, the porosity parameter, and the slip velocity parameter. The graphical computation is performed for a specified range of parameters, such as 0 ≤ m ≤ 2.5, 0 ≤σm ≤ 2.5, 0 ≤ K1 ≤ 1.5, 0.5 ≤ Pr ≤ 3.0, 0 ≤σ≤ 1.5, 0.5 ≤ Sc ≤ 2.0, 0.2 ≤ Nb ≤ 0.8, and 0.2 ≤ Nt ≤ 0.8.

关键词： viscoelasticity-based micropolar nanofluid porous medium slip effect numerical method

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Nursery practice on seed germination and seedling growth of Dalbergia sissoo using beneficial microbial inoculants

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Journal of Forestry Research 2011年第2期22卷 189-192页

作者： B.m.Khan m.K.Hossain m.A.u.mridha Institute of Forestry and Environmental Sciences University of ChittagongChittagong-4331Bangladesh Department of Botany University of Chittagong

Nursery practice using microbial inoculants was performed to find out the efficacy of the inoculants on seed germination and seedling growth of sissoo（Dalbergia sissoo Roxb.）.microbial inoculants or effective microorganisms（Em） are a mixture of many different beneficial microorganisms in a *** seedlings were grown in a mixture of sandy soil and cowdung（3：1） kept in polybags with pouring Em solution at different concentrations（0.1%,0.5%,1%,2%,5% and 10%） before and after a week of sowing the *** germination rate and growth parameters of seedlings were measured,such as,shoot and root length,vigor index,fresh and dry weight of shoot and root and total biomass *** nodulation status influenced by Em was also observed along with the measurement of pigment contents in *** highest germination rate（69%） was observed in 2% Em treatment,followed by 67% and 65% in 1% and 5% *** highest shoot length（33.2 cm） was in 2% Em,whereas highest root length（26.3 cm） was in 1% *** fresh and dry weights from shoot and root,were maximum（4.16 g and 1.57 g;2.12 g and 0.83 g respectively） in 2% Em and were significantly（p ≤ 0.05） different from *** index was highest（4071） in 2% Em,which was significantly（p ≤ 0.05） different from *** dry weight increment was highest in 2% Em treatment,followed by 1% and 5% concentrations of *** number was higher at very low（0.1%） concentration of Em solution but it normally decreased with the increase of Em *** contents of chlorophyll a,chlorophyll b and carotenoid were highest（60.11,17.05 and 42.48 mg·L1respectively） in 2% Em treatment and lowest（39.35,13.55 and 27.29 mg·L-1 respectively） in control ***,low concentration of Em（up to 2%） can be used for getting maximum seed germination rate and seedling development of Dalbergia sissoo Roxb.

关键词： Dalbergia sissoo Roxb. microbial inoculants(Em) germination rate seedling growth leaf's pigment nodulation status

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Optimization Study of Pulsed DC Nitrogen-Hydrogen Plasma in the Presence of an Active Screen Cage

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Plasma Science and Technology 2014年第5期16卷 460-464页

作者： A.SAEED A.W.KHAN F.JAN H.u.SHAH m.ABRAR m.ZAKA-uI-ISLAm m.KHALID m.ZAKAuLLAH National Centre for Physics Quaid-i-Azam University Campus Islamabad Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Department of Physics Faculty of ScienceUniversity of Jazan

A glow discharge plasma nitriding reactor in the presence of an active screen cage is optimized in terms of current density,filling pressure and hydrogen concentrations using optical emission spectroscopy（OES）.The samples of AISI 304 are nitrided for different treatment times under optimum *** treated samples were analyzed by X-ray diffraction（XRD） to explore the changes induced in the crystallographic *** XRD pattern confirmed the formation of iron and chromium nitrides arising from incorporation of nitrogen as an interstitial solid solution in the iron lattice.A Vickers microhardness tester was used to evaluate the surface hardness as a function of treatment time（h）.The results showed clear evidence of improved surface hardness and a substantial amount of decrease in the treatment time compared with the previous work.

关键词： optical diagnostics plasma nitriding austenitic stainless steel

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