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Structural, electronic, elastic, and th.rmal properties of CaNih3 perovskite obtained from first-principles calculations

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Chinese Physics B 2018年第3期27卷 384-390页

作者： S Benlamari h Bendjeddou r Boulechfar SAmara Korba h meradji r Ahmed S Ghemid r Khenata S Bin Omran Laboratoire LPr Departement de Physique Faculté des Sciences Université Badji Mokhtar Annaba Algeria Department of Physics Faculty of Science Universiti Teknologi Malaysia UTM Skudai 81310 Johor Malaysia Laboratoire de Physique Quantique et de Modelisation Mathematique de la Matiere (LPQ3M) Universite de Mascara-29000-Algeria Department of Physics and Astronomy College of Science King Sand University P.O. Box 2455 Riyadh 11451 Saudi Arabia

A theoretical study of the structural, elastic, electronic, mechanical, and th.rmal properties of the perovskite-type hydride CaNih3 is presented. This study is carded out via first-principles full potential （FP） linearized augmented plane wave plus local orbital （LAPW＋lo） method designed within the density functional theory （DFT）. To treat the exchange-correlation energy/potential for the total energy calculations, the local density approximation （LDA） of Perdew-Wang （PW） and the generalized gradient approximation （GGA） of Perdew-Burke-Ernzerhof （PBE） are used. The three independent elastic constants （C11, C12, and C44） are calculated from the direct computation of the stresses generated by small strains. Besides, we report the variation of the elastic constants as a function of pressure as well. From the calculated elastic constants, the mechanical ch.racter of CaNih3 is predicted. Pertaining to the th.rmal properties, the Debye temperature is estimated from the average sound velocity. To furth.r comprehend this compound, the quasi-h.rmonic Debye model is used to analyze the th.rmal properties. From the calculations, we find that the obtained results of the lattice constant （ao）, bulk modulus （Bo）, and its pressure derivative （B0′） are in good agreement with the available theoretical as well as experimental results. Similarly, the obtained electronic band structure demonstrates the metallic ch.racter of this perovskite-type hydride.

关键词： perovskite-type hydrides elastic constants hydrogen storage materials

Mode filtering based on ponderomotive force nonlinearity in a plasma filled rectangular waveguide

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Plasma Science and Technology 2017年第10期19卷 70-74页

作者： h SOBhANI h.r SABOUhI S FEILI E DADAr Young research.rs and Elite Club Qom Branch Islamic Azad University Department of Electrical Engineering Hormoz Branch Islamic Azad University Department of Physics Shahid Bahonar University Faculty of Economic Mofid University

h.re a new scheme for mode filtering is proposed. Based on the ponderomotive force effect,propagation of the microwave dual-mode through a plasma-filled metallic rectangular waveguide is investigated. To excite the TE_（20） mode in a rectangular waveguide, the existence of fundamental modes is unavoidable. To filter the destructive mode（TE_（10））, the waveguide is filled with a collisional plasma. Based on the coupling effect, the energy of this destructive TE_（10） mode is transferred to the TE_（20） mode. The proposed structure acts like a mode convertor. The TE_（10） mode become more attenuated and instead the TE_（20） mode is amplified. The plasma filled rectangular waveguide acts as a mode filtering tool.

关键词： mode filtering mode convertor collisional plasma ponderomotive force

On Poincare-Friedrichs Type Inequalities for the Broken Sobolev Space W^(2,1)

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Numerical Mathematics(Theory,methods and Applications) 2021年第1期14卷 31-46页

作者： r.h.W.hoppe Department of Mathematics University of HoustonUSA Department of Mathematics University of AugsburgGermany

We are concerned with the derivation of Poincare-Friedrichs type inequalities in the broken Sobolev space W^(2,1)(Ω;T h)with.respect to a geometrically conforming,simplicial triagulation T h of a bounded Lipschitz domainΩin r d,d∈*** inequalities are of interest in the numerical analysis of nonconforming finite element discretizations such as C^(0) Discontinuous Galerkin(C^(0)DG)approximations of minimization problems in the Sobolev space W^(2,1)(Ω),or more generally,in the Banach space BV^(2)(Ω)of functions of bounded second order total *** an application,we consider a C^(0) DG approximation of a minimization problem in BV^(2)(Ω)which is useful for texture analysis and management in image restoration.

关键词： Poincare-Friedrichs inequalities broken Sobolev spaces C^(0)Discontinuous Galerkin approximation image processing

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染整加工中泡沫的形成与消除

国际纺织导报 2007年第10期35卷 50-52页

作者： h.rsch 李娴 Zschimmer & Schwarz Mohsdorf公司

纺织湿整理中的泡沫有时候是必需的(如在泡沫涂层整理中),但多数情况下是不希望产生的。泡沫会给湿加工过程带来干扰,或在织物表面形成斑点。常见的干扰有使织物浮在液面上,在染机内形成导流,使得测定和计量不准,机器堵塞,以及织物轧液... 详细信息

纺织湿整理中的泡沫有时候是必需的(如在泡沫涂层整理中),但多数情况下是不希望产生的。泡沫会给湿加工过程带来干扰,或在织物表面形成斑点。常见的干扰有使织物浮在液面上,在染机内形成导流,使得测定和计量不准,机器堵塞,以及织物轧液过程中携液不均。由于泡沫中染料沉积以及不溶性物质如油脂等在织物表面的浓缩形成色斑。

关键词：整理工艺泡沫消泡剂

National Antibiotic resistance Strategy for human health in France

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China CDC weekly 2022年第49期4卷 1097-1100页

作者： Céline Pulcini Anne Berger-Carbonne Bruno Coignard Jérôme Salomon The Ministerial Mission for the Prevention of Infections and Antibiotic resistance Ministry of Health and PreventionParisFrance Infectious Diseases Division French National Public Health AgencySaint-MauriceFrance French Chief medical Officer General Director for HealthWHO EB MemberHERA Board MemberMinistry of Health and PreventionParisFrance

France is a country with 67 million inhabitants and is part of the European *** consumption in humans is high.r in France as compared to the European average,especially in outpatient settings(1–2).The burden of antibiotic resistance is also high,as compared to the European average,with an estimated 5,500 deaths per year associated with multidrug-resistant bacterial infections(3).Encouraging results have,however,been observed over the last several years:antibiotic consumption in the community,in nursing homes and in hospitals showed a decreasing trend,as well as certain resistant bacteria,such as 3rd-generation cephalosporin-or fluoroquinolone-resistant Esch.richia coli(1–2,4–5).The COVID-19 pandemic has had a dramatic impact on antibiotic consumption and its long-term impact on antibiotic resistance is being carefully monitored(1).

关键词： Antibiotic nursing Strategy

Determination of Trace Amounts of Vanadium by Kinetic-Catalytic Spectrophotometric methods

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Chinese Journal of Chemistry 2006年第4期24卷 557-562页

作者： POUrETEDAL, h.r. KEShAVArZ, M.h. Department of Chemistry Malek-ashtar University of Technology Shahinshahr Iran

Kinetic-catalytic spectrophotometric methods were proposed for the determination of trace amounts of vanadium element as vanadium（Ⅳ） and/or V（Ⅴ） ions. The vanadium（Ⅳ） as VO^2＋ ion and/or vanadium（Ⅴ） as VO3^- ion showed a catalytic effect on the kinetic reactions between a color reagent such as methylthymol blue （MTB） or SPADNS and bromate in acidic media. The rate of decrease in the absorbance of the reagent MTB at 440 nm or SPADNS at 510 nm was proportional to concentration of V（Ⅳ） and/or V（Ⅴ） ions in the solution. The linear ranges for determination of vanadium were obtained in the range of 1.0-150 and 5.0-100.0 μg/L by the fixed-time and slope methods, respectively, with using MTB as reagent. In the presence of SPADNS as reagent, the calibration curves were made in the amplitude 1.0-200.0 and 5.0-150 μg/L of vanadium ion by the fixed-time and slope methods, respectively. Using fixed-time method, the limits of detection were obtained to be 0.5 and 0.7 μg/L of vanadium in the presence of MTB and SPADNS as reagents, respectively. Detection limits of vanadium by slope method and reagents of SPADNS and MTB were obtained to be 3.5 and 3.8 μg/L of vanadium, respectively. The proposed methods were applied successfully to determination of vanadium in synthetic and real samples.

关键词： kinetic-catalytic method SPADNS methylthymol blue vanadium

Fabrication of porous titanium carbide ceramics by gelcasting process

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rare metals 2022年第9期41卷 3220-3227页

作者： h.Foratirad M.G.Maragheh h.r.Bah.rvandi Materials and Nuclear Fuel research School Nuclear Science and Technology Research InstituteTehran14155-1339Iran Department of Materials Science and Engineering MUTTehran15875-1774Iran

Titanium carbide ceramics with high porosity were fabricated by gelcasting process with methacrylamide as a chain forming monomer,methylenebisacrylamide as a cross-linker monomer and tetramethylammonium hydroxide as a *** stability of suspension,mechanical properties,phase composition and micro structure were investigated by zeta potential,bending and compressive strengths,X-ray diffraction and scanning electron microscopy(TEM) analyses,*** results show that the optimal concentration of dispersant for the best homogeneous unagglomerated microstructures is 0.4 wt%at ph *** highest green strength of 33 MPa is obtained from the suspension with 40 vol% solid loading and25 wt% *** porosity increases with the increase in monomer content and the decrease in solid ***,the strength of porous TiC ceramic decreases with the content of pores increasing in the sintered ceramics.

关键词： Titanium carbide Porous ceramic Gelcasting Bending strength

Saint-Venant torsion analysis of bars with.rectangular cross-section and effective coating layers

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Applied Mathematics and mechanics(English Edition) 2016年第2期37卷 237-252页

作者： h.TEIMOOrI r.T.FAAL r.DAS Department of Mathematics and Computer Science Allameh Tabatabai University Faculty of Engineering University of Zanjan Department of mechanical Engineering and Centre for Advanced Composite Materials University of Auckland

This paper investigates the torsion analysis of coated bars with a rectangular cross-section. Two opposite faces of a bar are coated by two isotropie layers with different materials of the original substrate that are perfectly bonded to the bar. With the Saint- Venant torsion theory, the governing equation of the problem in terms of the warping function is established and solved using the finite Fourier cosine transform. The state of stress on the cross-section, warping of the cross-section, and torsional rigidity of the bar are evaluated. Effects of thickness of the coating layers and material properties on these quantities are investigated. A set of graphs are provided that can be used to determine the coating thicknesses and material properties so as to keep the maximum von Mises stress on the cross-section below an allowable value for effective use of the coating layer.

关键词： Saint-Venant torsion rectangular cross-section coating layer torsional rigidity

Low-Energy Direct Capture in the ^12C（α, γ）^16O reaction

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Chinese Physics Letters 2014年第6期31卷 67-71页

作者： h. Sadeghi r. Ghaselni Department of Physics Faculty of Science Arak University Arak 8349-8-38156 Iran

The spectra of light nuclei provide the first test of nuclear interaction models. The reaction amount determines the relative abundance of most elements in red giant stars, neutron stars, and black holes. Due to the fact that this reaction occurs at low energies, the experimental measurement is very difficult and perhaps impossible. In this work, the radiative capture of the ^12C（α, γ）^16O reaction at very low-energies is taken as a case study. Using the M3Y potential we calculate the astrophysical Factor for transition E1 and E2. In comparison with oth.r theoretical methods and available recent experimental data, excellent agreement is achieved for the astrophysical S-factor of this process.

关键词： Giant stars