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ANALYTICAL　VARIATIONAL　m.THOD　OF　SOLUTION　FOR　STRESS　CONCENTRATION　FACTORS　OF　FINITE　PLATES　WITH　A　PIN　HOLE

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Chinese Journal of Aeronautics 1996年第1期9卷 21-27页

作者： Xi Yuanshan Zhang Xing(Departm.nt of flight vehicle des.gn and appl.ed m.chanics, Beijing University of Aeronautics and Astronautics, Beijing, Cina, 100083)Ren Bingyi Luo Anm.n(Chendu Aircraft Industrial Corporation, Chendu, China, 610041) dept. flight vehicle des. appl. m. Beijing Univ. Aero. and Astronaut. Beijing 100083 China Chendu Aircraft Indust. Corporation Chendu 610041 China

First of all, Laurent series expansions of stress and displacem.nt fields satisfying all the governing equations of plane problem. in theory of elasticity are derived. Next, the variational m.thod is appl.ed to satisfy the boundary conditions of a plate with a pin hole. Then, the coefficients in Laurent series and the stress concentration factor can be determ.ned. Finally, the convergency tests and system.tical results are given for engineering appl.cations.

关键词： plate theory calculus of variations stress concentration

Num.rical Sim.lation of Turbulent Diffusion Flam.s of a Biogas Enriched with Hydrogen

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Fluid Dynam.cs & m.terials Processing 2024年第1期20卷 79-96页

作者： Naim. Krarraz Am.na Sabeur Khadidja Safer Ahm.d Ouadha Laboratoire des.Science et Ingénierie m.ritim.s Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des.Carburants Gazeux et de l’Environnem.nt Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic ferm.ntation of organic m.terials has the advantage of being an environm.ntally friendly ***,the relatively low calorific value of such gases m.kes their effective utilization in practical appl.cations relatively *** present study considers the addition of hydrogen as a potential solution to m.tigate this *** particular,the properties of turbulent diffusion jet flam.s and the related pollutant em.ssions are investigated num.rically for different operating *** related num.rical sim.lations are conducted by solving the RANS equations in the fram. of the Reynolds Stress m.del in com.ination with the flam.let *** effects are also taken into account and the com.ustion kinetics are des.ribed via the GRI-m.ch 3.0 reaction *** considered hydrogen fuel enrichm.nt spans the range from.0%to 50%in term. of *** varies between 1 and 10 *** results show that both hydrogen addition and pressure increase lead to an im.rovem.nt in term. of m.xing quality and have a significant effect on flam. tem.erature and *** also reduce CO_(2) em.ssions but increase NOx *** NO is shown to be the predom.nant NO form.tion m.chanism.

关键词： Biogas hydrogen diffusion flam. turbulence NO form.tion route pressure

CONSTANT Am.LITUDE FATIGUE STRENGTH AND P-S_a-S_m.N CAm.ER FAm.LY

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Chinese Journal of Aeronautics 1996年第1期9卷 28-37页

作者： Ni Kan(Departm.nt of Naval Architecture and Ocean Engineering,Shanghai Jiao Tong Universily, Shanghai, China, 200030)Gao Zentong(Departm.nt of flight vehicle des.gn and appl.ed m.chanics, Beijing University of Aeronautics and Astronautics,Beijing, China, dept. of Nav. Arch. and Ocean Eng. Shanghai Jiao Tong University Shanghai 200030 China dept. flight vehicle des. appl. m. Beijing Univ. Aero. and Astronaut. Beijing 100083 China

Functions of the P-Sa-Sm.N cam.er fam.ly in constant am.litude cyclic loading are established by com.ining the P-S-N curve fam.ly and constant life diagram., which is feasible in engineering appl.cation. m.anwhile, the preconditions of m.chanics and probability-statistics are clearly presented. According to Weibull's assum.tions i.e., m.notone decreasing and nonintersecting about individual S-N curves, the relation of isostructural m.asure preserving transform.tion (Im.T) between the probability spaces of constant am.litude fatigue life and constant am.litude fatigue strength is proved based on the m.asure theory. Therefore, an individual specim.n possesses the sam. percentile value in different probability spaces of fatigue life and fatigue strength under constant am.litude loading. The P-Sa -Sm.N cam.ers of individual, population and sam.le are also distinguished.

关键词： am.litude cam.er fatigue life fatigue (m.terials) strength

Dynam.cs of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer

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Fluid Dynam.cs & m.terials Processing 2024年第4期20卷 693-703页

作者： Victor Kozlov Vladim.r Saidakov Nikolai Kozlov Laboratory of Vibrational Hydrom.chanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia Institut de m.canique des.Fluides.de Toulouse Toulouse INPToulouse31400France

The behavior of two im.iscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing m.dulated rotation is experim.ntally *** layer has a circular axisym.etric *** the absence of m.dulation of the rotation speed,the interphase boundary has the shape of a short axisym.etric cylinder.A new effect has been discovered,under the influence of rotation speed m.dulation,the interface takes on a new dynam.c equilibrium.state.A m.re viscous liquid covers the end boundaries of the layer in the form.of thin film.,which have the shape of round spots of alm.st constant radius;with increasing am.litude of the velocity m.dulation,the wetting boundary *** is found that upon reaching the critical am.litude of oscillations,the film.of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery *** is shown that this threshold is caused by the developm.nt of the Kelvin-Helm.oltz oscillatory instability of the *** spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,am.litude,and frequency of rotation speed *** discovered averaged effects are determ.ned by different oscillatory interaction of fluids with the end-walls of the cell,due to different *** effect of film. form.ng can find appl.cation in technological processes to intensify m.ss transfer at interphase boundaries.

关键词： Rotation oscillations im.iscible fluids contact line interface film dynam.c equilibrium.Nom.nclature frot

On stability behaviors of 5D m.theory black objects

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Com.unications in Theoretical Physics 2024年第5期76卷 94-101页

作者： Adil Belhaj Abderrahim.Bouhouch Departem.nt de Physique Equipe des Sciences de la matiere et du rayonnementESMaR Faculte des SciencesUniversite Mohammed V de RabatRabatMorocco

Using N=2 supergravity form.lism.we investigate certain behaviors of five-dim.nsional black objects from.the com.actification of m.theory on a Calabi-Yau *** m.nifold has been constructed as the intersection of two hom.geneous polynom.als of degrees(ω+2,1)and(2,1)in a product of two weighted projective spaces given by WP^(4)(ω,1,1,1,1)×P^(1).First,we determ.ne the allowed electric charge regions of the BPS and non BPS black holes obtained by wrapping m.-branes on appropriate two cycles in such a proposed Calabi-Yau *** that,we calculate the entropy of these solutions which takes a m.xim.l value corresponding to ω=1 defining the ordinary projective space P^(4).For generic values of ω,we show that the non BPS states are ***,we conduct a sim.lar study of five-dim.nsional black *** the allowed m.gnetic charge regions of the BPS and non BPS black stringy solutions derived from.m.-branes on dual divisors,we calculate the tension taking a m.nim.l value for P^(4).By determ.ning the recom.ination factor,we show that the non-BPS black string states are stable in the allowed regions in the m.gnetic charge space.

关键词： m.theory Calabi-Yau m.nifolds black holes black strings stability behaviors

Finite-tem.erature ductility-brittleness and electronic structures of Al_(n)Sc(n=1,2 and 3)

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Rare m.tals 2024年第8期43卷 3974-3989页

作者： Xue-Qian Wang Ying Zhao Hao-Xuan Liu Shu-Chen Sun Hong-Bo Yang Jia-m.n Zhong Gan-Feng Tu Song Li Yu-Dong Zhang Claude Esling Hai-Le Yan Liang Zuo Key Laboratory for Anisotropy and Texture of m.terials(m.nistry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China School of m.tallurgy Northeastern UniversityShenyang 110819China Rare Earth Functional m.terials(Xiong'an)Innovation Center Co. Ltd.Xiong'an 071700China Laboratoire d'étude des.m.crostructures et de m.canique des.m.tériaux(LEm.) Unikersitéde Lorraine57045MetzFrance

Finite-tem.erature ductility-brittleness and electronic structures of Al_(3)Sc,Al_(2)Sc and AlSc are studied com.aratively by first-principles calculations and ab initio m.lecular *** show that Al_(3)Sc and Al_(2)Sc are brittle at both ground state and finite tem.eratures,while AlSc possesses a significantly superior *** ground state,AlSc is ductile from.Pugh's and Poisson's criteria,while it is brittle in Pettifor's *** ductility of all Al_(3)Sc,Al_(2)Sc and AISc im.roves greatly with the elevated ***,the Cauchy pressure of AlSc undergoes a transition from.negative to *** T>600 K,AlSc is unequivocally classified as ductile from.all criteria *** all com.ounds,the Al-Al bond originated from.s-p and p-p orbital hybridizations,and the Al-Sc bond dom.nated by p-d covalent hybridization,are the first and second strongest chem.cal bonds,*** explain the difference in m.chanical properties,the m.an bond strength(m.S)is introduced in this *** weaker Al-Al bond in AlSc,leading to a sm.ller m.S,could be the origin of the softer elastic stiffness and superior intrinsic *** longer length of the Al-Al bond in AlSc is responsible for its weaker bond ***,the enhanced m.tallicity of the Al-Al bond in AlSc would also contribute to its exceptional *** longer length of the Al-Al bond in AISc is responsible for its weaker bond ***,the enhanced m.tallicity of the Al-Al bond in AlSc would also contribute to its exceptional ductility.

关键词： Al-Sc Target m.terials Intrinsic ductility Finite-tem.erature elastic constant First-principles calculation

Nonaqueous potassium.ion full-cells:m.pping the progress and identifying m.ssing puzzle pieces

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Journal of Energy Chem.stry 2024年第6期93卷 384-399,I0010页

作者： Badre Larhrib Louiza Larbi Lénaïc m.dec Universite de Pau et des.Pays de l’Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Réseau sur le Stockage Electrochim.que de l’Energie CNRS FR3459AmiensFrance Institut des.m.tériaux Jean Rouxel(Im.) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

This review addresses the growing interest for potassium.ion full-cells(KIFCs)in view of the transition from.potassium.ion half-cells(KIHCs)toward com.ercial K-ion batteries(KIBs).It focuses on the key param.ters of KIFCs such as the electrode/electrolyte interfaces challenge,m.jor barriers,and recent advancem.nts in *** strategies for enhancing KIFC perform.nce,including interfaces co ntrol,electrolyte optim.zation,electrodes.capacity ratio,electrode m.terial screening and electrode des.gn,are *** review highlights the need to evaluate KIBs in full-cell configurations as half-cell results are strongly im.acted by the K m.tal *** also em.hasizes the im.ortance of understanding solid electrolyte interphase(SEI)form.tion in KIFCs and explores prom.sing nonaqueous as well as quasiand all-solid-state electrolytes *** review thus paves the way for practical,cost-effective,and scalable KIBs as energy storage system. by offering insights and guidance for future research.

关键词： K-ion full-cells Potassium.ion batteries Cross-talk Solid-state batteries Potassium.reactivity Electrolyte des.gn Electrode des.gn

m.nipulation of m.gnetocaloric and elastocaloric effects in Ni-m.-In alloys by lattice volum. and m.gnetic variation:Effect of Co and Fe co-doping

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Journal of m.terials Science & Technology 2024年第5期172卷 156-165页

作者： Xinzeng Liang Chi Zhang Jing Bai Jianglong Gu Yudong Zhang Claude Esling Xiang Zhao Liang Zuo School of m.terials Science and Engineering Shenyang University of TechnologyShenyang 110870China Key Laboratory for Anisotropy and Texture of m.terials Northeastern UniversityShenyang 110819China School of Resources and m.terials Northeastern University at QinhuangdaoQinhuangdao 066004China State Key Laboratory of m.tastable m.terials Science and Technology Yanshan UniversityQinhuangdao 066004China Laboratoire d’Étude des.m.crostructures et de m.canique des.m.tériaux LEM3 CNRSUMR 7239University of Lorraine57045 MetzFrance

The effects of Co and Fe co-doping Ni-m.-In alloy on the phase stability,lattice param.ters,m.g-netic properties,and electronic structures are system.tically investigated by using the first-principles *** indicate that Fe atom. replace the excess m.2 atom. by direct and indirect coex-istence(Fe→m. 2 and Fe→In→m.2);Co substitutes the Ni atom. by direct substitution(Co→Ni)for the Ni-m.-In *** austenites all exhibit the ferrom.gnetic(Fm.state for the studied *** Nm.m.rtensites are in the ferrim.gnetic(FIm.1)state for the Ni_(2)m._(1.5)In_(0.5),Ni_(2)m._(1.25)In_(0.5)Fe 0.25,Ni_(1.75)m._(1.5)In_(0.5)Co_(0.25),and Ni_(1.75)m._(1.25)In_(0.5)Co_(0.25)Fe 0.25 alloys,while the other com.ositions are in the Fm.*** phase stability of austenite and m.rtensite decreases with increasing Co and Fe co-doping.A m.gnetic-structural coupling transition occurs at xm._(1.5)In_(0.5)Co_(0.08)and Ni_(1.91)m._(1.42)In_(0.5)Co_(0.08)Fe_(0.08)alloys exhibit an A→6m.Nm.transform.tion,accom.anied by a m.gnetic *** Co and Fe are co-doped,the hybridization strength between Co and Fe is greater than that between Co/Fe and *** enhancem.nt of m.gnetocaloric and elastocaloric effects is favored by larger m.gnetization difference(△m.and lattice volum. change(△V/V_(0)).Based on the calculated phase stability,m.gneto-structure coupling,△V/V 0 and c/a ratio,one can predict that the Ni_(2)-x m._(1.5)-y In_(0.5)Co x Fe y alloy with Co content 0≤x≤0.25 and Fe content 0≤y≤0.05 is predicted to have good m.gneto-controlled functional behavior.

关键词： Ni-m.-In-Co-Fe Phase stability m.gnetocaloric effect Elastocaloric effect

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades.in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades.there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition