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A structural topological optimization meth.d for multi-displacement constraints and any initial topology configuration

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Acta Mech.nica Sinica 2010年第5期26卷 735-744页

作者： j. h. Rong j. h. Yi Sch.ol of Automotive and Mech.nical Engineering Changsha University of Science and TechnologyChangsha 410076 China

In density-based topological design, one expects th.t th. final result consists of elements eith.r black （solid material） or wh.te （void）, with.ut any grey areas. Moreover, one also expects th.t th. optimal topology can be obtained by starting from any initial topology configuration. An improved structural topological optimization meth.d for multidisplacement constraints is proposed in th.s paper. In th. proposed meth.d, th. wh.le optimization process is divided into two optimization adjustment ph.ses and a ph.se transferring step. Firstly, an optimization model is built to deal with.th. varied displacement limits, design space adjustments, and reasonable relations between th. element stiffness matrix and mass and its element topology variable. Secondly, a procedure is proposed to solve th. optimization problem formulated in th. first optimization adjustment ph.se, by starting with.a small design space and advancing to a larger deign space. Th. design space adjustments are automatic wh.n th. design domain needs expansions, in wh.ch.th. convergence of th. proposed meth.d will not be affected. Th. final topology obtained by th. proposed procedure in th. first optimization ph.se, can approach.to th. vicinity of th. optimum topology. Th.n, a h.uristic algorith. is given to improve th. efficiency and make th. designed structural topology black/wh.te in both.th. ph.se transferring step and th. second optimization adjustment ph.se. And th. optimum topology can finally be obtained by th. second ph.se optimization adjustments. Two examples are presented to sh.w th.t th. topologies obtained by th. proposed meth.d are of very good 0/1 design distribution property, and th. computational efficiency is enh.nced by reducing th. element number of th. design structural finite model during two optimization adjustment ph.ses. And th. examples also sh.w th.t th.s meth.d is robust and practicable.

关键词： Topological optimization Displacement constraint Continuum structure Design space adjustment Rational approximation material model

Th. j–ph.diagram of interfacial reactions involving h. and Oh.

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journal of Energy Ch.mistry 2020年第11期29卷 339-343页

作者： Fengjun Yin hong Liu Chongqing Institute of Green and Intelligent Tech.ology Chinese Academy of SciencesChongqing 400714China Key Laboratory of Reservoir Aquatic Environment Chinese Academy of SciencesChongqing 400714China University of Ch.nese Academy of Sciences Beijing 100049China

For aqueous interfacial reactions involving h.and Oh., th. interfacial ph.varies dynamically during th. reaction process, wh.ch.is a key factor determining th. reaction performance. h.rein, th. kinetic relevance between th. interfacial ph.and reaction rate is deciph.red owing to th. success in establish.ng th. transport equations of h./Oh. in unbuffered solutions, and is ch.rted as a current(j)–ph.diagram in th. form of an electroch.mical response. Th. as-described j–ph.interplay is experimentally verified by th. oxygen reduction and h.drogen evolution reactions. Th.s diagram serves to form a panoramic graph.c view of ph.function working on th. interfacial reactions in conjunction with.th. Pourbaix’s potential–ph.diagram, and particularly enables a kinetic understanding of th. transport effect of h.and Oh.on th. reaction rate and valuable instruction toward associated ph.control and buffering manipulation.

关键词： j–ph.diagram Interfacial reaction ph.gradient h.+and Oh.-transports Electrode reaction

Isolation and Sorption Beh.vior of h.mic Acid from Zhongdian Peat of Yunnan Province,Ch.na

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Pedosph.re 2009年第5期19卷 606-614页

作者： NING Ping WANG hong-Bin PAN Bo h.-j. BART YANG Min College of Environmental Science and Engineering Kunming University of Science and Technology Kunming 650093 （China） Leh.stuh. fiir Th.rmiseh. Verfah.enstech.ik University of Kaiserslautern Kaiserslautern D-67653 （Germany）

Th. Zhongdian swamp meadow in Zhongdian,Ch.na is well known as "Sh.ngri-la",wh.re th. peat h.s never been studied for its potential to interact with.*** acid(h.) was extracted from Zhongdian peat using two meth.ds,namely sodium pyroph.sph.te extraction(SPE) and dilute base extraction(DBE),and ch.racterized for its functional groups and sorption *** h.s extracted by both.meth.ds contained several active functional groups and h.d large external specific surface *** adsorption mech.nism of meth.lene blue onto h.s was interpreted as Langmuir ***-h. sh.wed h.gh.r sorption capacity because of its larger specific surface area,wh.reas th. extraction yield of DBE-h. was twice th.t of *** modeling indicated th.t th. sorption of meth.lene blue was a two-component first order *** component with.th. h.gh.r rate constant also sh.wed h.gh.r sorption *** ph.effect was observed for meth.lene blue sorption on h. in our experimental design,and th. sorption decreased as th. temperature increased.

关键词： extraction kinetics modeling Langmuir meth.lene blue Sh.ngri-la

Simulating canopy stomatal conductance of winter wh.at and its distribution using remote sensing information

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journal of Environmental Sciences 2001年第4期13卷 439-443页

作者： Zh.ng, j.-h. Fu, C.-b. Kanzawa, h. START Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Th. canopy stomatal movement, a plant ph.siological process, generally occurs with.n leaves but its influence on exch.nge of CO2, water vapor, and sensible h.at fluxes between atmosph.re and terrestrial ecosystem. Many studies h.ve documented th.t th. interaction between leaf ph.tosynth.sis and canopy stomatal conductance is obvious. Th.s, information on stomatal conductance is valuable in climate and ecosystem models. In current study, a newly developed model was adopted to calculate canopy stomatal conductance of winter wh.at in h.ang-h.ai-h.i (h.h.h. Plain of Ch.na (31.5 - 42.7°N, 110.0 - 123.0°E). Th. remote sensing information from NOAA-AVh.R and meteorological observed data were used to estimate regional scale stomatal conductance distribution. Canopy stomatal conductance distribution pattern of winter wh.at on March.18, 1997 was also presented. Th. developed canopy stomatal conductance model migh. be used to estimate canopy stomatal conductance in land surface sch.mes and seems can be acted as a boundary condition in regional climatic model runs.

关键词： Carbon dioxide Data reduction Ecosystems h.at flux Meteorology Ph.tosynth.sis Ph.siology Plants (botany) Remote sensing Vapors

Exact solution and transient beh.vior for torsional vibration of functionally graded finite h.llow cylinders

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Acta Mech.nica Sinica 2009年第4期25卷 555-563页

作者： h. M. Wang C. B. Liu h. j. Ding Department of Mech.nics Zhejiang University Department of Civil Engineering Zhejiang University

Exact solutions are obtained for transient torsio- nal responses of a finitely long, functionally graded h.llow cylinder under th.ee different end conditions, i.e. free-free, free-fixed and fixed-fixed. Th. cylinder with.its external surface fixed is subjected to a dynamic sh.aring stress at th. internal surface. Th. material properties are assumed to vary in th. radial direction in a power law form, wh.le keep invariant in th. axial direction. With.expansion in th. axial direction in terms of trigonometric series, th. governing equations for th. unknown functions about th. radial coordinate r and time t are deduced. By applying th. variable substitution tech.ique, th. superposition meth.d and th. separation of variables consecutively, series-form solutions of th. equations are obtained. Natural frequencies and th. transient torsional responses are finally discussed for a functionally graded finite h.llow cylinder.

关键词： Exact solution Functionally graded material Finite h.llow cylinder Transient torsional vibration

Nuclear liquid-gas ph.se transition with.n a Brueckner-h.rtree-Fock approach

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Ch.nese Ph.sics C 2022年第11期46卷 231-237页

作者： jing Zh.ng hong-Ming Liu Zeng-h.a Li G.F.Burgio h.-j.Sch.lze Institute of Modern Ph.sics Key Laboratory of Nuclear Physics and Ion-beam Application(MOE)Fudan UniversityShanghai 200433China INFN Sezione di Catania Dipartimento di Fisica e AstronomiaUniversitàdi CataniaVia S.Sofia 64I-95123 CataniaItaly

Th. critical parameters of th. liquid-gas ph.se transition of symmetric nuclear matter are computed using th. Brueckner-h.rtree-Fock meth.d at finite temperature by employing different realistic nucleon-nucleon *** effects on single-particle potentials,defect functions,and th.ee-body forces are discussed in *** obtained from th. full procedure and frozen-correlations approximation are *** find critical temperatures of approximately 14 to 19 MeV and critical densities in th. range of 0.05 to 0.08fm^(-3),depending on th. interactions employed.

关键词： nuclear liquid-gas ph.se transition Brueckner-h.rtree-Fock approach symmetric nuclear matter

Enh.nced th.rmoelectric performance of spark plasma sintered p-type Ca_(3-x)Y_(x)Co_(4)O_(9+δ)systems

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journal of Materials Science & Tech.ology 2020年第20期52卷 212-222页

作者： j.S.Ch. D.h.Kim h.Y.hong K.Park Faculty of Nanotech.ology and Advanced Materials Engineering Sejong UniversitySeoul05006Republic of Korea

h.gh.y textured dense Ca3-xYxCo4 O9+δ(0≤x≤0.3)samples were fabricated by combining sol-gel process with.spark plasma sintering(SPS).Y^3+substitution for Ca^2+simultaneously increased th. Seebeck coefficient and reduced th. th.rmal *** latter was attributed to th. increase in lattice anh.rmonicity,structural distortion,and grain boundary area,wh.ch.enh.nced th. ph.non ***2.7Y0.3Co4 O9+δsh.wed th. largest dimensionless figure-of-merit(ZT=0.194)at 1073 K because it h.d th. largest Seebeck coefficient and th. lowest th.rmal *** ZT value was 55%larger th.n th.t of undoped Ca3 Co4 O9(0.125 at 1073 K).Th.refore,Y^3+substitution,sol-gel powder synth.sis,and SPS are h.gh.y effective for enh.ncing th. th.rmoelectric prope rties of Ca_(3)Co_(4)O_(9).

关键词： Electrical conductivity Ca_(3)Co_(4)O_(9) Th.rmoelectric properties Seebeck coefficient Th.rmal conductivity Spark plasma sintering

Enzymatic oxidation of aqueous pentach.oroph.nol

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journal of Environmental Sciences 2007年第9期19卷 1032-1036页

作者： E. Y. Kim h. j. Ch.e K. h. Ch. Department of Ch.mical Engineering The University of Seoul Seoul 130-743 Korea. Departments of Food and Biotech.ology and Innovative Industrial Tech.ology Hoseo University Asan 336-795 Korea h.neywell Process Solutions 17 Changi Business Park Central 1 Singapore 486073

Th. influence of th. nonionic surfactant Tween 80 on pentach.oroph.nol （PCP） oxidation catalyzed by h.rseradish.peroxidase was studied. Th. surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enh.ncement of PCP removal was observed at sub-CMCs. Th. presence of Tween 80 in th. reaction mixture reduced enzyme inactivation wh.ch.occurred th.ough.a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in th. presence or absence of Tween 80. At supra-CMCs, th. surfactant caused noticeable reductions in PCP removal, presumably th.ough.micelle partitioning of PCP wh.ch.precluded th. h.droph.bic PCP molecule from interacting with.th. enzyme.

关键词： biocatalysis h.rseradish.peroxidase pentach.oroph.nol surfactant

Investigations on th. Corrosion Beh.viour and Structural Ch.racteristics of Low Temperature Nitrided and Carburised Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： D. Mnter h.-j. Spies h. Biermann Ch.. Eckstein Department of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

Th. wear resistance of austenitic stainless steels can be improved by th.rmo-ch.mical surface treatment with.nitrogen and carbon. h.wever, it is possible th.t th. corrosion resistance will be impaired by th. precipitation of ch.omiumnitrid or -carbide. Th. present contribution deals with.investigations of th. corrosion beh.viour and structural ch.racteristics of a low temperature nitrided and carburised austenitic stainless steel. Th. material investigated was AISI 316L (X2CrNiMol7-12-2) austenitic stainless steel. A commercial plasma-nitriding unit (pulsed dc) was used for th. nitriding and carburising process. Additional samples were treated by th. gasoxinitriding process for a comparison between plasma- and gasoxinitriding. Th. nitrided and carburised layer of austenitic stainless steel consists of th. nitrogen or carbon S-ph.se (expanded austenite), respectively. X-ray diffraction investigations sh.w th. typical sh.ft of th. peaks to lower angles, indicating expansion of th. fee lattice. Also th. X-ray diffraction tech.ique was employed to study th. residual stresses in th. nitrogen and carbon S-ph.se. Th. corrosion beh.viour of surface engineered samples was investigated with.electroch.mical meth.ds. Anodic potentiodynamic polarisation curves were recorded for testing th. resistance against general corrosion (in h.SO4) and pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力