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Effect of rare earths on phase transformation in as-cast ZA2. alloy dur-ing compressive creep

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Rare Metals 2003年第4期22卷 259-264页

作者： WEIXiaowei SHENBaoluo DepamnentofAppliedPhysics UniversityofElectronicScienceandTechnologyofChinaChengdu610045China DeparlanentofMetalScience SichuanUniversityChengdu610065China

The effect of the mixed rare earths of Ce on the phase transformation in ascast ZA 2. alloy during compressive was investigated under 37 MPa and at 160 deg C by X-raydiffraction technique and SEM. The results showed that the as cast microstructure of ZA 2.-RE alloyconsisted of a dendritic Al-rich alpha' surrounded by Zn-rich beta' phase, interdendritic epsilonphase and Zn-rich eta phase together with a complex Z phase which was a complex constitute compound,(RE,Cu)Al_5Zn_(16), dispersed in crystal interfaces or branch crystal interfaces and stable duringcompressive creep test at 160 deg C. The phase transformations of ZA 2.-RE alloy, decomposition ofbeta' phase arid four transformation, were delayed by the addition of rare earths, also the lamellarstructure and the spheroidized structure in ZA 2.-RE alloy were finer than in ZA 2. alloy duringcompressive creep test at 160 deg C at the same creep time, and the compressive creep resistance ofZA 2.-RE alloy was higher than that of ZA 2. alloy.

关键词： microstructure change compressive creep rare earths ZA 2. alloy

The Synthesis of New Sulfur-containing Chiral Macrocyclic Ligands

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Chinese Chemical Letters 1997年第10期8卷 853-854页

作者： Xiao Ling ZHANG Jing Song YOU Xing Shu LI Ru Gang XIE(department of chemistry, {2. Union university, chengdu 610064) department of chemistry Sichuan Union University Chengdu 610064 China

Five new chiral sulfur-containing macrocyclic ligands which can be used in chiral recognition to guests have been synthesized and characterized

关键词： OCH Li Cl The Synthesis of New Sulfur-containing Chiral Macrocyclic Ligands

Persistence of bounded solutions to degenerate Sobolev-Galpern equations

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Science china Mathematics 2010年第11期53卷 2831-2846页

作者： ZHU ChangRong1 & ZHANG WeiNian2. 1School of Mathematics, Chongqing university, Chongqing 400044, china 2.angtze Center of Mathematics and {2. of Mathematics, sichuan university, chengdu 610064, china School of Mathematics Chongqing University Chongqing China Yangtze Center of Mathematics and department of Mathematics Sichuan University Chengdu China

In this paper the persistence of bounded solutions to degenerate evolution equations of Sobolev-Galpern type is discussed. In order to define the evolution operator well, we study the existence and uniqueness of solutions to its linear form. On this basis we discuss exponential dichotomies of the evolution operator and give the Fredholm alternative result for bounded solutions of nonhomogeneous linear degenerate equations. This result enables us to give a condition for the persistence of bounded solutions of a general degenerate nonlinear autonomous equation under a nonautonomous perturbation.

关键词： degenerate evolution equation Sobolev-Galpern type boundedness Fredholm alternative exponential dichotomy

Study on Syntheses and Characterizations of Polymethylphenethylsilane, Polymethylcyclohexylsilane and their Copolymers

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Journal of Central South university 2000年第2期12卷 92-96页

作者： HU Hui ping 1,HUANG Ke long 1,PAN Chun yue 1,CHEN De ben 2.(1 College of chemistry and Chemical Engineering, Central South university of Technology, Changsha 410083,{2. 2.department of chemistry, sichuan university, chengdu 610064,{2. College of chemistry and Chemical Engineering Central South University of Technology Changsha China department of chemistry Sichuan University Chengdu China

The effects of adding cosolvents of diglyme and 15-crown-5 to the reaction mixture of Wurtz-type coupling of dichlorosilanes on the yield and relative molecular mass dispersity of polymethylphenethylsilane(PMPES) were discussed. The results show that addition of 10%(volume ratio of diglyme to toluene) diglyme as a cosolvent to the reaction mixture leads to the yield increase of PMPES with a monomodal distribution of relative molecular masses. Adding 10%diglyme to the reaction mixtures, the yields of polymethylcyclohexylsilane(PMCS) and copolymers (polymethylphenethylsilane-co-methylcyclohexylsilane), (the molar ratios of methylphenethyldichlorosilane to methylcyclohexyldichlorosilane were 2.0, 1.0 and 0.5, and the copolymers were abbreviated by Copolymers I, II, III, respectively) are 47%, 52., 54%, 53%, respectively. Their relative molecular masses ([`(M)]w )(\bar M_w ) almost reach 105. These polysilanes were characterized by 1H-NMR, IR and UV absorption spectrum.

关键词： polysilane cosolvent synthesis characterization

Studies on the Technology and Mechanism of Laser Photoinduced Alignment of Liquid Crystal

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Chemical Research in Chinese Universities 1998年第4期14卷 94-96页

作者： HE Yu e WANG Zhan qi and XIE Ming gui (department of chemistry,{2., chengdu, 610064) CAI Bang wei and BI Guo jiang (department of Opt Electronic & Science,{2., chengdu, 610064) sichuan Univ Dept Chem Chengdu 610064 Peoples R China sichuan Univ Dept Optelect & Sci Chengdu 610064 Peoples R China

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｎｉｓｏｔｒｏｐｙｏｆｌｉｑｕｉｄｃｒｙｓｔａｌｓｍａｋｅｓｉｔｐｏｓｓｉｂｌｅｔｏｂｅｍａｄｅｉｎｔｏｍａｎｙｋｉｎｄｓｏｆｅｌｅｃ－ｔｒｏ－ｏｐｔｉｃｄｅｖｉｃｅｓ．Ｗｈｅｎｔｈｅ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｎｉｓｏｔｒｏｐｙｏｆｌｉｑｕｉｄｃｒｙｓｔａｌｓｍａｋｅｓｉｔｐｏｓｓｉｂｌｅｔｏｂｅｍａｄｅｉｎｔｏｍａｎｙｋｉｎｄｓｏｆｅｌｅｃ－ｔｒｏ－ｏｐｔｉｃｄｅｖｉｃｅｓ．ＷｈｅｎｔｈｅｔｈｉｃｋｎｅｓｓｏｆｔｈｅＬＣｃ...

关键词： Liquid crystal(LC) Laser photoinduced alignment Polarization controller High power laser

On the Birch-Swinnerton-Dyer Conjecture of Elliptic Curves E_D:y^2.x^3-D^2.

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Acta Mathematica Sinica,English Series 2000年第2期16卷 229-236页

作者： Delang Li department of Mathematics,sichuan Union {2.,chengdu 610064,P.R.china Ye Tian department of Mathematics,Columbia {2.,New York,NY 1002.,USA department of Mathematics Sichuan Union University Chengdu 610064 P. R. China department of Mathematics Columbia University New York NY 10027 USA

We prove in this paper that the BSD conjecture holds for a certain kind of elliptic curves.

关键词： Elliptic curve BSD conjecture Graph 2.component

Control of the Rendition Wavelength Shifts of Color Lippmann Holograms Recordedin Single-layer panchromatic Silver-halide Emulsion

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Chinese Journal of Lasers 2000年第2期9卷 155-160页

作者： ZHU Jianhua, GUO Lurong, LI Zuoyou, LIU Zhenqing (Information Optics Institute, sichuan university, chengdu 610064,{2. Institute of Southwest Find Physics, chengdu 610003,{2. ) 四川大学四川成都中国工程物理研究院西南流体物理所四川成都

Russian PFG-03C panchromatic ultra-high resolution silver-halide emulsion is regarded as the most successful material for the fabrication of color reflection holograms. But the lack of established and reliable processing sequences prevents its practical applications in business and everyday life. Though much attention is drawn upon the processing of PFC-03C color reflection holograms, the color desaturation is still a problem. The article describes the new processing of color holograms recorded in PFC- 03C plates which is demonstrated experimentally to have the capacity of controlling the rendition wavelength shifts and improving the color desaturation effectively. The rendition spectra of Red-Green-Blue (R. G. B. ) single-line reflection holographic gratify, and the color reflection hologram as well, are given in this paper.

关键词： color holography reflection holograms rendition wavelength color desaturation

Study on the two and three-parameter working stability regions of 3Y-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2. ZHANG Xinni3, CHEN Sha’ou3 & QI Ping3 1. department of chemistry, Qingdao {2., Qingdao 2.6071, china 2. department of chemistry, Tsinghua {2., Beijing 100084, china 3. department of Physics, Qingdao {2., Qingdao 2.6071, china department of chemistry Qingdao University Qingdao China department of chemistry Tsinghua University Beijing China department of Physics Qingdao University Qingdao China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

A taxonomic re-assessment in the Chinese Bupleurum(Apiaceae):Insights from morphology,nuclear ribosomal internal transcribed spacer,and chloroplast(trnH-psbA,matK) sequences

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Journal of Systematics and Evolution 2011年第6期49卷 558-589页

作者： Chang-Bao WANG Xiang-Guang MA Xing-Jin HE(College of Life Science,sichuan university,{2. 610064,china) (College of Life Science Sichuan University Chengdu 610064 China)

As one of the big genera in Apiaceae,Bupleurum *** received considerable attention from plant ***,there are still many gaps in our knowledge of this genus,especially of those species endemic to china that have often been excluded from previous *** spite of a few recent studies on the phylogeny and classification of the Chinese Bupleurum,the most essential problem of species delimitation still remains *** re-evaluate the taxonomy of the Chinese Bupleurum using morphological and molecular *** observations of living plants growing the field and herbarium specimens were made to understand the morphological variation and to ensure species identification for the molecular *** analyses were carried out on sequence data of nuclear ribosomal internal transcribed spacer(nrITS),trnH-psbA,and matK,using parsimony and Bayesian approaches to evaluate species *** of both nrITS and combined datasets of the three regions revealed the following results:(i)the Chinese Bupleurum species were divided into two major lineages;and(ii)most species were well defined,but some traditional inter-and infraspecific relationships were not *** results,along with the results of previous works support that the Chinese Bupleurum species were derived from two different lineages and should be placed in Neves and Watson’s subgenus *** detailed taxonomic re-assessment of several Chinese species resulted in new taxonomic recombinations with rank changes for three species:Bupleurum tenerum,***,and ***;new combination for one variety,*** ***;and the description of one variety and one species,*** *** and ***.

关键词： Chinese Bupleurum chloroplast sequences(trnH-psbA matK) morphology nrITS phylogenetic analyses taxonomy and new species.