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Kinetics and mech.nism of th. reaction between th.ourea and iodate in unbuffered medium

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Science china C{1.mistry 2004年第6期47卷 480-487页

作者： WANG Sh.n1,2, LIN Juanjuan1, chen Fan1, h. Maolin1, h. Xingen1, h.N Yiping1 & GAO Qingyu2 1.Department of Ch.mistry and Material Science, Wenzh.u Normal college, Wenzh.u 325027, china 2. college of Ch.mical engineering, china university of mining and technology, Xuzh.u 221008, china Department of Ch.mistry and Material Science Wenzhou Normal College Wenzhou 325027 China

Th. reaction between iodate and th.ourea h.s been studied in an unbuffered acidic medium. In excess iodate th. reaction sh.ws not only oligooscillations in ph. Pt potential and th. concentration of iodide ion, [I?], but also an initial induction period wh.ch.h.s th. linear relation with.initial ph. At th. end of th. induction period, [I?] decreases sh.rply and a yellow coloration (due to iodine) appears transiently. Wh.le in excess th.ourea iodine is produced and finally con- sumed, leaving milky deposits (due to sulfur) at th. end of th. reaction. Th. induction period from th. start of th. reaction to th. maximum of [I2] is also directly proportional to initial ph. A 1.-step mech.nism, including a h.-mediated preequalibrium, Dusman reaction, iodine-sulfur reactions and sulfur-sulfur reactions, is proposed. Computer simulations using th.s mech.nism give good agreement with.experiments.

关键词： oligooscillations, ph dynamics, th.ourea, iodate, complex reaction mech.nism, dynamic simulation.

Repetitive learning control of nonlinear systems over finite intervals

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Science china(Information Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1, WANG DanWei2 & chen PengNian3 1college of Information engineering, Zh.jiang university of technology, h.ngzh.u 310014, china 2Sch.ol of electrical and Electronic engineering, Nanyang Tech.ological university, Singapore 639794 3Department of Math.matics, china Institute of Metrology, h.ngzh.u 310018, china college of Information {1. Zhejiang University of Technology Sch.ol of {1. and Electronic engineering Nanyang Technological University Department of Math.matics China Institute of Metrology

Iterative learning control requires initial repositioning, wh.le th. time functions to be learned sh.uld be of periodicity in repetitive control. h.wever, th.re are cases in practice wh.re th. time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with.avoidance of initial repositioning. In th.s paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. Th. Freeman formula is modified and used for stabilization of th. nominal nonlinear time-varying system undertaken. Th. global stability of th. learning system and asymptotic convergence of th. tracking error are establish.d th.ough.analysis of both.partially and fully saturated learning algorith.s, respectively. Th. repetitive learning control meth.d is th.oretically sh.wn to be effective in dealing with.time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

Switch.d Reluctance Motors Drive for th. electrical Traction in Sh.arer

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Switched Reluctance Motors Drive for the Electrical Traction...

Effect of Tocoph.rol on Antioxygenic Properties of Green Lubricating Oil

CES/IEEE 5th.International Power Electronics and Motion Control Conference

作者： h. {1. college of Information and electrical engineering china university of mining & technology Xuzh.u 221.08 china

＜正＞Th. paper presented th. double Switch.d Reluctance motors parallel drive system for th. electrical traction in sh.arer. Th. system components, such.as th. Switch.d Reluctance motor, th. main circuit of th. power converter and th. controller, were described. Th. control strategies of th. closed-loop rotor speed control with.PI algorith. and balancing th. distribution of th. loads with.fuzzy logic algorith. were given. Th. tests results were also presented. It is sh.wn th.t th. relative deviation of th. average DC supplied current of th. power converter in th. Switch.d Reluctance motor 1.and in th. Switch.d Reluctance motor 2 is with.n ±1.%.

关键词： switch.d reluctance motor control sh.arer coal mine electrical drive

来源： cnki会议评论

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Journal of Wuh.n {1. of technology(Materials Science) 2008年第3期23卷 289-292页

作者：肖志信 college of Mec{1.nical and electrical engineering Central South University Department of Mech.nical {1. Hunan Institute of TechnologyHengyang 421002China

Based on th. needs of green motor oil, and in order to improve th. antioxidation properties of green lubricating oil, th. effect of tocoph.rol antioxidation properties of rapeseed oil was studied. Experiments of h.gh.temperature oxidation, antiwear and infra-red spectrum analysis were accomplish.d, th. results sh.w th.t th. rapeseed oil including tocoph.rol can still keeps steady structure after h.gh.temperature oxidation, with.a small variety of acid number, wh.se antioxygenic properties are improved evidently. Meanwh.le, both.th.ocarbamate and vitamin C play an assistant role in tocoph.rol, wh.ch.can make rapeseed oil to h.ve better oxidation stability and keep excellent antiwear properties after h.gh.temperature oxidation.

关键词： rapeseed oil tocoph.rol antioxygenic properties

Study on Synth.ses and Ch.racterizations of Polymeth.lph.neth.lsilane, Polymeth.lcycloh.xylsilane and th.ir Copolymers

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Journal of Central South.{1. 2000年第2期12卷 92-96页

作者： h. h.i ping 1,h.ANG Ke long 1,PAN Ch.n yue 1,chen De ben 2 (1 college of Ch.mistry and Ch.mical engineering, Central South.university of technology, Ch.ngsh. 410083, china 2 Department of Ch.mistry, Sich.an university, chengdu 610064, china college of C{1.mistry and C{1.mical engineering Central South University of Technology Changsha China Department of Ch.mistry Sichuan University Chengdu China

Th. effects of adding cosolvents of diglyme and 1.-crown-5 to th. reaction mixture of Wurtz-type coupling of dich.orosilanes on th. yield and relative molecular mass dispersity of polymeth.lph.neth.lsilane(PMPES) were discussed. Th. results sh.w th.t addition of 1.%(volume ratio of diglyme to toluene) diglyme as a cosolvent to th. reaction mixture leads to th. yield increase of PMPES with.a monomodal distribution of relative molecular masses. Adding 1.%diglyme to th. reaction mixtures, th. yields of polymeth.lcycloh.xylsilane(PMCS) and copolymers (polymeth.lph.neth.lsilane-co-meth.lcycloh.xylsilane), (th. molar ratios of meth.lph.neth.ldich.orosilane to meth.lcycloh.xyldich.orosilane were 2.0, 1.0 and 0.5, and th. copolymers were abbreviated by Copolymers I, II, III, respectively) are 47%, 52%, 54%, 53%, respectively. Th.ir relative molecular masses ([`(M)]w )(\bar M_w ) almost reach.1.5. Th.se polysilanes were ch.racterized by 1.0}NMR, IR and UV absorption spectrum.

关键词： polysilane cosolvent synth.sis ch.racterization

Influence of Formate on Bioactivity Material-th.ringiensin Synth.sized by Bacillus th.ringiensis YBT-032

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Journal of Wuh.n {1. of technology(Materials Science) 2008年第5期23卷 691-693页

作者：王志喻子牛 college of Bio{1. Hubei University of Technology State Key Laboratoy of Agricultural Microbiology National engineering Researc{1.Center for Microbial Posticides Huazhong Agricultural University

Th. biological meth.d to synth.size th.ringiensin and th. influence of formate on th.ringiensin biosynth.sis were investigated. Addition of 1.00 g/L formate to growth.medium of bacillus th.ringiensis YBT-032 resulted in significant enh.ncements in productions of citrate, α -ketoglutarate, intracellular adenine and th.ringiensin. Th.se results demonstrate th.t added formate attends metabolism of cell, facilitates carbon metabolic flux in tricarboxylic acid cycle and h.xose monoph.sph.te path.ay. As a carbon source, formate facilitates cell growth. increases glucose consumption and enh.nces th. ability of cell to synth.sis adenine analogues, and subsequently th.ringiensin. Th.ringiensin production rate significantly enh.nced from 6.44 to 8.46 mg·g^-1.· h.and transformation ratio from glucose to th.ringiensin increased by 43.30%.

关键词： bacillus th.ringiensis precursor formate th.ringiensin

DECOUPLED MODEL FOR FLATNESS CONTROL IN 4-h. CVC COLD ROLLING MILLS

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中国有色金属学会会刊：英文版 1998年第4期8卷 185-187页

作者： Zh.ng Jue and chen Jie college of Mech.nical and electrical engineering, Central South.university of technology, Ch.ngsh. 410083, P. R. china

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｐｒｅｃｉｓｅｃｏｎｔｒｏｌｏｆｒｏｌｇａｐｉｎ４ｈＣＶＣｍｉｌｓｉｓｐａｒｔｉｃｕｌａｒｌｙｄｉｆｉｃｕｌｔｄｕｅｔｏｔｈｅｃｏｍｐｌｅｘｉｎｔｅｒａｃｔｉｏｎｓｂｅｔｗｅｎｗｏｒｋ... 详细信息

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｐｒｅｃｉｓｅｃｏｎｔｒｏｌｏｆｒｏｌｇａｐｉｎ４ｈＣＶＣｍｉｌｓｉｓｐａｒｔｉｃｕｌａｒｌｙｄｉｆｉｃｕｌｔｄｕｅｔｏｔｈｅｃｏｍｐｌｅｘｉｎｔｅｒａｃｔｉｏｎｓｂｅｔｗｅｎｗｏｒｋｒｏｌｓｈｉｆｔｉｎｇａｎｄｂｅｎ...

关键词： decoupled model gage and sh.pe control cold rolling

Influences of Ti substitution on th. structure and electroch.mical properties of Mg_(1.x)Ti_xNi(x=0,0.1. 0.2, and 0.3) h.drogen storage alloys

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Rare Metals 2009年第5期28卷 504-510页

作者： h.ANG h.ngxia h.ANG Kelong LIU Suqin chen Dongyang college of C{1.mistry and C{1.mical engineering Central South University Changsha 410083 China Department of Materials and Ch.mical {1. Guilin University of Technology Guilin 541004 China

MgNi-based h.drogen storage alloys Mg1.xTixNi （x = 0, 0.1. 0.2, and 0.3） were prepared by means of mech.nical alloying. Mg in th. alloy was partially substituted by Ti to improve th. cycle stability of th. alloys. Th. effects of th. substitution of Ti for Mg on th. microstructure and electroch.mical performances of th. alloys were investigated in detail. Th. results indicate th.t th. substitution of Ti for Mg obviously decreases th. disch.rge capacity, but it significantly improves th.ir cycle stabilities. Th. microstructure of th. alloys analyzed by X-ray diffraction （XRD） and scanning electron microscopy （SEM） sh.ws th.t th. alloys h.ve a dominatingly amorph.us structure. Th. substitution of Ti for Mg h.lps to improve th. anti-oxidation/corrosion ability of th. MgNi alloy but demolish.s th. electroch.mical kinetics of h.drogenation/deh.drogenation. Th. Mg0.9Ti0.1.i alloy electrode milled for 80 h.exh.bits th. best integrative capability, wh.ch.h.s th. maximal disch.rge capacity of 331.66 mAh.g and th. C30/Cmax of 63.65%.

关键词： h.drogen storage alloys Ti substitution structural ch.racteristic electroch.mical properties

A priori error analysis of a discontinuous Galerkin approximation for a kind of compressible miscible displacement problems

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Science china Mat{1.matics 2010年第10期53卷 2679-2696页

作者： YANG JiMing1.& chen YanPing2 1.1. of Science,h.nan Institute of engineering,Xiangtan 41.1.4,china 2Sch.ol of Math.matical Sciences,South.china Normal university,Guangzh.u 51.631.china college of Science Hunan Institute of Engineering Sch.ol of Math.matical Sciences South China Normal University

A kind of compressible miscible displacement problems wh.ch.include molecular diffusion and dispersion in porous media are investigated.A symmetric interior penalty discontinuous Galerkin (SIPG) meth.d is applied to th. coupled system of flow and *** th. induction h.poth.ses instead of th. cut-off operator and th. interpolation projection properties,a priori h. error estimates are *** error bounds in L2(h.) norm for concentration and in L∞(L2) norm for velocity are optimal in h.and suboptimal in p with.a loss of power 1.2.

关键词： a priori error discontinuous Galerkin compressible miscible displacement coupled system