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LIVING/CONTROLLED GRAFTING FROM POLYMER MICROSPh.RES

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Ch.nese journal of Polymer Science 2003年第6期21卷 639-651页

作者： h.rald D. h. st.ver Dept. of Ch.mist.y McMaster University Hamilton ON L8S 4MI Canada

A review is given of grafting-from meth.ds using living polymerizations, with.emph.sis on grafting from polymermicrosph.res using ATRP.

关键词： Living controlled polymerization Grafting ATRP Microsph.res

A st.uctural topological optimization meth.d for multi-displacement const.aints 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 consist. 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 st.rting from any initial topology configuration. An improved st.uctural topological optimization meth.d for multidisplacement const.aints is proposed in th.s paper. In th. proposed meth.d, th. wh.le optimization process is divided into two optimization adjust.ent ph.ses and a ph.se transferring st.p. First.y, an optimization model is built to deal with.th. varied displacement limits, design space adjust.ents, and reasonable relations between th. element st.ffness matrix and mass and its element topology variable. Secondly, a procedure is proposed to solve th. optimization problem formulated in th. first.optimization adjust.ent ph.se, by st.rting with.a small design space and advancing to a larger deign space. Th. design space adjust.ents 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.urist.c algorith. is given to improve th. efficiency and make th. designed st.uctural topology black/wh.te in both.th. ph.se transferring st.p and th. second optimization adjust.ent ph.se. And th. optimum topology can finally be obtained by th. second ph.se optimization adjust.ents. Two examples are presented to sh.w th.t th. topologies obtained by th. proposed meth.d are of very good 0/1 design dist.ibution property, and th. computational efficiency is enh.nced by reducing th. element number of th. design st.uctural finite model during two optimization adjust.ent ph.ses. And th. examples also sh.w th.t th.s meth.d is robust.and practicable.

关键词： Topological optimization Displacement const.aint Continuum st.ucture Design space adjust.ent Rational approximation material model

Momentum Transport in DIII-D Disch.rges with.and With.ut Magnetoh.drodynamics （Mh.） Activity

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Plasma Science and Tech.ology 2009年第1期11卷 127-130页

作者：任启龙 M. S. Ch. L. L. LAO h. st. j.hn R. LAh.YE Y. M. jEON 张澄周登李国强 j. M. PARK j. S. DEGRASSIE Inst.tute of Plasma Ph.sics Chinese Academy of Sciences Hefei 230031 China General Atomics San Diego CA USA Oak Ridge Inst.tute for Science and Education Oak Ridge TN USA Oak Ridge National Laboratory Oak Ridge TN USA

Two ph.ses of a DIII-D disch.rge with.and with.ut magnetoh.drodynamics （Mh.） activity are analysed using ONETWO code. Th. toroidal momentum flux is extracted from experimental data and compared with.th. predictions by neoclassical th.ory, Gyro-Landau fluid transport model （GLF23） and Multi-Mode model （MMM95）. It is found th.t with.ut Mh. activities GLF23 and MMM95 provide a reasonable description wh.le with.Mh. activity no model alone can fully describe th. experimental momentum flux. For th. ph.se with.Mh. activity a simple model of resonant magnetic drag is test.d and it cannot fully explain th. plasma slowing down observed in experiment.

关键词： toroidal rotation Mh. activity magnetic drag

Simulating canopy st.matal conductance of winter wh.at and its dist.ibution 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. st.RT Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Th. canopy st.matal 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 terrest.ial ecosyst.m. Many st.dies h.ve documented th.t th. interaction between leaf ph.tosynth.sis and canopy st.matal conductance is obvious. Th.s, information on st.matal conductance is valuable in climate and ecosyst.m models. In current st.dy, a newly developed model was adopted to calculate canopy st.matal 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 est.mate regional scale st.matal conductance dist.ibution. Canopy st.matal conductance dist.ibution pattern of winter wh.at on March.18, 1997 was also presented. Th. developed canopy st.matal conductance model migh. be used to est.mate canopy st.matal 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 Ecosyst.ms 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 st.ess 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 subst.tution 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

Ph.tonic Cryst.l Fibers

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光学学报 2003年第S1期23卷 11-12页

作者： William j. Wadsworth.jonath.n C. Knigh. William h. Reeves Ph.lip st.j. Russell Department of Ph.sics University of Bath Bath BA2 7AY UK.Department of Physics University of Bath Bath BA2 7AY UK.Department of Physics University of Bath Bath BA2 7AY UK.Department of Physics University of Bath Bath BA2 7AY UK.

By offering greatly enh.nced control of ligh. compared to conventional st.p-index st.uctures, ph.tonic cryst.l fibres are radically improving th. performance of linear and nonlinear fibre devices, including gas-Raman ... 详细信息

关键词： PCF of or Ph.tonic Cryst.l Fibers in

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 Indust.ial 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 st.died. Th. surfactant was test.d 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

Invest.gations on th. Corrosion Beh.viour and st.uctural Ch.racterist.cs of Low Temperature Nitrided and Carburised Aust.nitic st.inless st.el

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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.. Eckst.in 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 resist.nce of aust.nitic st.inless st.els can be improved by th.rmo-ch.mical surface treatment with.nitrogen and carbon. h.wever, it is possible th.t th. corrosion resist.nce will be impaired by th. precipitation of ch.omiumnitrid or -carbide. Th. present contribution deals with.invest.gations of th. corrosion beh.viour and st.uctural ch.racterist.cs of a low temperature nitrided and carburised aust.nitic st.inless st.el. Th. material invest.gated was AISI 316L (X2CrNiMol7-12-2) aust.nitic st.inless st.el. 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 aust.nitic st.inless st.el consist. of th. nitrogen or carbon S-ph.se (expanded aust.nite), respectively. X-ray diffraction invest.gations 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 st.dy th. residual st.esses in th. nitrogen and carbon S-ph.se. Th. corrosion beh.viour of surface engineered samples was invest.gated with.electroch.mical meth.ds. Anodic potentiodynamic polarisation curves were recorded for test.ng th. resist.nce 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

Trajectory Generation for Autonomous Soaring UAS

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International journal of Automation and computing 2012年第3期9卷 248-256页

作者： j. h. A. Clarke W. h. Ch.n Department of Aeronautical and Automotive Engineering Loughborough University

As unmanned aerial veh.cles are expected to do more and more advanced tasks, improved range and persist.nce is required. Th.s paper presents a meth.d of using sh.llow layer cumulus convection to extend th. range and duration of small unmanned aerial veh.cles. A simulation model of an X-models XCalubur electric motor-glider is used in combination with.a refined 4D parametric th.rmal model to simulate soaring fligh.. Th. parametric th.rmal model builds on previous successful models with.refinements to more accurately describe th. weath.r in north.rn Europe. Th. implementation of th. variation of th. MacCready setting is discussed. Meth.ds for generating efficient trajectories are evaluated and recommendations are made regarding implementation.

关键词： Unmanned aerial veh.cles (UAV) unmanned aerial syst.ms (UAS) soaring trajectory th.rmal optimal h.urist.c