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RING-OPENING polymerIZATION OF TRIMETHYLENE CARBONATE BY CALIX[8]ARENE-NEODYMIUM

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Chinese Journal of polymer science 2000年第1期18卷 77-80页

作者： Ling Ge Zhi-quan Shen Yi-feng Zhang Qiao-hong Huang department of polymer {2. and Engineering, zhejiang university, hangzhou 31002., china zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

Ring-opening polymerization of trimethylene carbonate (TMC) with a rare earth calixarene compound as catalyst has been studied for the first time. The effect of TMC/Nd (molar ratio) and polymerization conditions were investigated in detail. It was found that calix[8]arene-neodymium is a highly effective catalyst for the bulk polymerization of TMC and gives high molecular weight (M-v = 60,000) polymer. The optimum conditions of TMC polymerization were found to be as follows:TMC/Nd (molar ratio) = 2.000, 80 degrees C, 16 h. The polymers were characterized by NMR, GPC and DSC. Studying the mechanism by NMR showed that the polymerization of TMC catalyzed by calix[8]arene-neodymium proceeds via a cationic mechanism.

关键词： ring-opening polymerization trimethylene carbonate calixarene-neodymium

Correlation between rheological behavior and structure of multi-component polymer systems

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science china Chemistry 2008年第1期51卷 1-12页

作者： ZUO Min1,2.ZHENG Qiang1 1 Key Laboratory of Macromolecular Synthesis and Functionalization, Ministry of Education, department of polymer {2. and Engineering, zhejiang university, hangzhou 31002., china 2.department of Chemical Engineering, Hong Kong university of {2. and Technology, Clear Bay, Kowloon, Hong Kong 1. Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China 2. department of Chemical Engineering Hong Kong University of Science and Technology Clear Bay Kowloon Hong Kong China

Rheological measurement has been an effective method to characterize the structure and properties for multiphase/multi-component polymers, owing to its sensitivity to the structure change of hetero- geneous systems. In this article, recent progress in the studies on the morphology/structure and rheological properties of heterogeneous systems is summarized, mainly reporting the findings of the authors and their collaborators, involving the correlation between the morphology and viscoelastic relaxation of LCST-type polymer blends, the microstructure and linear/nonlinear viscoelastic behavior of block copolymers, time scaling of shear-induced crystallization and rheological response of poly- olefins, and the relationship between the structure/properties and rheological behavior of filled polymer blends. It is suggested that a thorough understanding of the characteristic rheological response to the morphology/structure evolution of multiphase/multi-component polymers facilitates researchers’ op- timizing the morphology/structure and ultimate mechanical properties of polymer materials.

关键词： heterogeneous polymer systems morphology and structure rheological properties viscoelastic relaxation

Low temperature albitization in Caino-Mesozoic reservoir sandstones from North Tarim, and a discussion on the fluid origin

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Chinese science Bulletin 1999年第S2期44卷 35-37页

作者： YE Ying~1, HU Shouxi~2.and SUN Jinggui~2.1. department of Earth sciences,{2., hangzhou 31002., china 2. department of Earth sciences, Nanjing university, Nanjing 2.0008, china department of Earth sciences Zhejiang University Hangzhou 310027 China department of Earth sciences Nanjing University Nanjing 210008 China

CAJNOZOIC and Mesozoic in North Tarim are predominantly a set of terrestrial detrital formations. In thereservoir sandstones in the area, albite is one of the widely developed authigenic mineral. Micro-structural evidence shows that diagenetic albite occurs as euhedral crystals in the pore, and replaces feldsparand other detritus along cleavage and micro-crack. EPMA analyzing found that some of the alteration product has a chemical composition between purealbite and the replaced detrital feldspar. For example, composition of replaced alkali feldspar is betweenmicrocline and albite, and content of altered plagioclase decreases continuously. This has been regardedas direct evidence for fluid replacement, for feldspar crystallized from solution or magma is usually withfixed chemical composition. Taking alkali feldspar as an example, although Kf and Ab forming completeisomorphous admixture in high temperature, they exsolved out as two relative pure phases while temperature decreases.

关键词： low temperature albitization sandstones fluid origin North Tarim.

SOME THERMODYNAMIC PROPERTIES OF Pd-In ALLOYS

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 311-317页

作者： YL. Chen(department of Materials science and Engineering,{2., hangzhou 31002., china) zhejiang Univ Hangzhou China

Some thermodynamic parnmeters of Pd-In alloys with 2.to 70 at. H indium have been determined in the temperuture range 800 to 1000℃ from e.m.f measurements ongalvanic cells with an onsen-cotzducting solid electrolyte. Heats of tnising calculated hem the activities are in excellent agreement with calorimetric data. The relative partial excess hee enengy of indiurn assumes unnsually larpe negative values ap to-174kJ/mol for Pd-rich alloys. Two efficts are discussed to account for the non-idealproperties: The rise Of Fermi enerpy as the valence electron8 of indium enter the 4dand 5sP bands of the alloy and the lattice distortion brought about by the differentmolar volumes of the cofnponents. The rise of the Fermi enerpy, as determlned fromthe activity data, indicates a strict adherence of the alloys to the rigid band model.

关键词： galvanic cell activity data Fermi energy,lattice distortion rigid band model

N-way blending problem of circular quadrics

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science china(Information sciences) 2010年第8期53卷 1546-1554页

作者： FANG MeiE 1,3 , Wang GuoZhao 2.& MA WeiYin 3 1 School of Computer science, hangzhou Dianzi {2., hangzhou 310081, china 2.department of Mathematics, zhejiang university, hangzhou 310018, china 3 department of MEEM, City {2. of Hong Kong, Hong Kong, china 1. School of Computer science Hangzhou Dianzi University Hangzhou 310081 China3. Department of MEEM City University of Hong Kong Hong Kong China2. Department of Mathematics Zhejiang University Hangzhou 310018 China

A method of blending circular quadrics with parametric patches is proposed in this paper. It needs n rational bi-cubic B′ezier patches and two S-patches to blend n (n > 2. quadrics. Bi-cubic rational B′ezier patches are used to G 1 -continuously blend each pair of adjacent base surfaces. These patches enclose two n-sided holes. And an S-patch is used to fill each hole, which keeps nearly G 1-continuity. Explicit formulas of control points for both B′ezier patches and S-patches are derived from their constraint conditions, which make modeling by blending quadrics very simple and convenient. In addition, the shapes of the blending surfaces can be intuitively adjusted by free parameters.

关键词： circular quadrics blending n-way S-patch

CRYSTAL GROWTH AND MAGNETO OPTICAL PROPERTIES OF Ce^(3 +) DOPED IRONG ARNET

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 353-356页

作者： M.Huang1) and S.Y.Zhang2. 1) department of Physics,zhejiang {2. , hangzhou 31002. ,china 2. department of Materials science & Engineering and State Key Laboratory of Silicon Materials,zhejiang Uni versity , hangzhou 31002. ,china zhejiang Univ Hangzhou China

Thispaperisconcerned withthe preparation ofcerium doped yttrium iron garnet which areknown to be an oxide withlarge magneto opticaleffect. Usingtheimproved flux method wesuccessfully grew the bulksinglecrystalsofiron garnet doped by Ce 3 + ions with maximum substitution upto0 349. Here weinvestigatedthedifferentcomposition ofsolution for maxi mum Ce3 + substitution. Thespectra ofthe Faraday rotation andtheoptical absorption were measured inthenearinfrared region fordifferentCe3 + ionsdopediron garnets. The Cesub stitution prominentlyenhancesthe Faradayeffect,andthe Yb and Euionssubstitutefor Yinthe dodecahedralsitesof YIGcanincreasetheconcentration of Ce3 + ions, depresstheforma tion of nonmagnetic Ce4 + ionsbythechargecompensation.

关键词： crystalgrowth Ce3 + doped iron Garnet magneto optical properties

Miktoarms hyperbranched polymer brushes:One-step fast synthesis by parallel click chemistry and hierarchical self-assembly

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science china Chemistry 2010年第12期53卷 2461-2471页

作者： HAN Yi & GAO Chao MOE Key Laboratory of Macromolecular Synthesis and Functionalization department of polymer {2. and Engineering,zhejiang university,hangzhou 31002.,china 1. MOE Key Laboratory of Macromolecular Synthesis and Functionalization department of polymer {2. and Engineering Zhejiang University Hangzhou 310027 China

Spherical molecular brushes with amphiphilic heteroarms were facilely synthesized by grafting the arms of hydrophobic 2.azidoethyle palmitate and hydrophilic monoazide-terminated poly(ethylene glycol) onto the core of alkyne-modified hyperbranched polyglycerol (HPG) with high molecular weight (Mn=12. kDa) via one-pot parallel click *** parallel click grafting strategy was demonstrated to be highly efficient (～100%),very fast (～ 2.h) and well controllable to the amphilicity of molecular *** adjusting the feeding ratio of hydrophobic and hydrophilic arms,a series of brushes with different arm ratios were readily *** resulting miktoarms hyperbranched polymer brushes (HPG-g-C16/PEG350) were characterized by hydrogen-nuclear magnetic resonance (1H NMR),Fourier transform infrared (FT-IR) spectroscopy,gel permeation chromatography (GPC),and differential scanning calorimetry (DSC) *** spherical molecular brushes showed high molecular weights up to 2.0 kDa,and thus could be visualized by atomic force microscopy (AFM).AFM and dynamic laser light scattering (DLS) were employed to investigate the self-assembly properties of amphiphilic molecular brushes with closed proportion of hydrophobic and hydrophilic *** brushes could self-assemble hierarchically into spherical micelles,and network-like fibre structures,and again spherical micelles by addition of n-hexane into the dichloromethane or chloroform solution of *** addition,this kind of miktoarms polymer brush also showed the ability of dye loading via host-guest encapsulation,which promises the potential application of spherical molecular brushes in supramolecular chemistry.

关键词： miktoarms molecular brushes hyperbranched polyglycerol amphiphilic self-assembly

Limit theory of restricted range approximations of complex-valued continuous functions

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science china Mathematics 2007年第10期50卷 1427-1440页

作者： Xian-fa LUO~1 Chong LI~(2.) ~1 School of Mathematics and Computer science,Jishou university,Jishou 416000,{2. ~2.department of Mathematics,zhejiang university,hangzhou 31002.,{2. 1. School of Mathematics and Computer science Jishou University Jishou 416000 China 2. department of Mathematics Zhejiang University Hangzhou 310027 China

This paper is concerned with the problem of the best restricted range approximations of complex-valued continuous functions. Several properties for the approximating set PΩ such that the classical characterization results and/or the uniqueness results of the best approximations hold are introduced. Under the very mild conditions, we prove that these properties are equivalent that P is a Haar subspce.

关键词： restricted range approximation, Haar subspace, characterization, uniqueness

Synthesis, catalytic and biological activity of novel dinuclear copper complex with Schiff base

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science china Chemistry 2006年第3期49卷 225-229页

作者： WEI Danyi1,2. LI Ning1, LU Gui1 & YAO Kemin1 1. department of Chemistry, zhejiang university,{2., china 2. Institute of Inorganic Chemistry, Ningbo university, Ningbo 3152.1, china 1. department of Chemistry Zhejiang University Hangzhou 310027 China 2. Institute of Inorganic Chemistry Ningbo University Ningbo 315211 China

A novel dinuclear copper complex with tetraglycol aldehyde-phenylalanineSchiff base has been synthesized. It was characterized and formulated as [Cu_2.(NO_3)]NO_3 byelemental analysis, magnetic susceptibility, TG-DTA, IR, EPR and ~1H NMR spectra. The obtainedcomplex can be used as a good catalyst for the polymerization of methyl methacrylate (MMA). Theoptimum polymerization conditions are: MMA/catalyst = 500 (molar ratio); [catalyst] =7.5x10^(-3)mol·L^(-1); dioxane as solvent; 80℃; 6 h. Polymethyl methacrylate (PMMA) with 80%conversion, 7.2.10^5 viscosity-average molecular weight and 60.5% syndiotacticity was obtained. Thiscomplex has also been shown to play an important role in scavenging O_2.-.

关键词： novel copper complex, Schiff base, catalytic activity, scavenging effect of O-·2.