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Rare Metals 2003年第1期22卷 6-9页

作者： WU Qingyindepartment of chemistry, zhejiang university, hangzhou 310027, China department of chemistry Zhejiang University Hangzhou 310027

The heteropoly complexes K_(13)[Ln(GeW_9Mo_2O_(39))_2] centre dot nH_2O (Ln =La, Ce, Pr, Nd, and Sm) were prepared for the first time and characterized by chemical analysis,infrared (IR) spectrum, ultraviolet (UV) spectrum, X-ray powder diffraction, and thermal ***, UV spectra, and X-ray powder diffraction studies show that the structure of the heteropolycomplexes is a square antiprism consisting of eight oxygen atoms of two GeW_9Mo_2O_(39)^(8-)heteropolyanions and a lanthanide ion. The thermostability of heteropoly complexes is lower thanthat of saturated Keggin structure dodecatungstogermanate.

关键词： inorganic chemistry heteropoly complex chemical synthesis lanthanates germanium

A Novel Approach for Determining the Orientation of 3-Hydroxyl Group of Some Steroids by CIMS

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Chinese Chemical Letters 1999年第2期10卷 143-144页

作者： Yuan Jiang PAN Yao Zu chen(department of chemistry, zhejiang university, hangzhou 310027) department of chemistry Zhejiang University Hangzhou 310027 China

Trimethylchlorosilane was used as a stereoselective reagent to determine the e or a orientation of 3-hydroxyl group of some steroids by chemical ionization mass spectrometry.

关键词： orientation of 3-hydroxyl group steroids mass spectrometric determination

A Facile and Efficient Synthesis of Substituted Pyrroles by Three Component Coupling Reaction of Amines, Aldehydes and Nitroalkanes

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Chinese Chemical Letters 2003年第9期14卷 893-896页

作者： Yi Song XIAO, Yan Guang wang department of chemistry, zhejiang university, hangzhou 310027 department of chemistry Zhejiang University Hangzhou 310027 China

A facile and efficient synthesis of highly substituted pyrroles has been achieved by a one-pot three-component coupling reaction of aldehyde, amine and nitroalkane by triethyl orthoformate.

关键词： Pyrrole nitroalkane aldehyde.

Microwave-assisted Regioselective 1-O-Deacylation of Peracylated Glycopyranoses on Alumina

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Chinese Chemical Letters 2003年第9期14卷 904-906页

作者： Jia Qiang DONG, shu Jia ZHANG, Yan Guang wang department of chemistry, zhejiang university, hangzhou 310027 department of chemistry Zhejiang University Hangzhou 310027 China

A facile, rapid and regioselective method for the 1-O-deacylation of peracylated glycopyranoses is described which occurs under mild conditions by absorption onto alumina using microwave irradiation.

关键词： Deacylation sugars regioselectivity microwave irradiation.

An Efficient Synthesis of Diaryl Ethers by Coupling Aryl Halides with Substituted Phenoxytrimethylsilane in the Presence of TBAF

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Chinese Chemical Letters 2003年第10期14卷 1012-1014页

作者： Jian Kui ZHAO, Yan Guang wang department of chemistry, zhejiang university, hangzhou 310027 department of chemistry Zhejiang University Hangzhou 310027 China

A general synthesis of diaryl ethers via coupling of aryl halides with substituted phenoxytrimethylsilane in the presence of TBAF is described. The protocol is simple and mild, and gives good to excellent yields.

关键词： Diaryl ether TBAF aryl halide phenoxytrimethylsilane.

POLYMERIZATION OF γ-STEARYL-α,l-GLUTAMATE N-CARBOXYANHYDRIDE USING RARE EARTH COORDINATION CATALYSTS

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Chinese Journal of Polymer Science 2000年第4期18卷 369-372页

作者： Xiao-ping Hu Jian Wu Zhi-kang Xu Lin-xian Feng Institute of Polymer Science, zhejiang university, hangzhou 310027, China department of chemistry, zhejiang university, hangzhou 310027, China 浙江大学浙江杭州

A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.

关键词： Rare earth coordination catalyst Ring-opening polymerization Polypeptide Poly(γ-stearyl-α,L-glutamate)

Immobilized chitosan as a selective absorbent for the nickel removal in water sample

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Journal of Environmental Sciences 2003年第5期15卷 633-638页

作者： WU Jian min, wang Yong yao (department of chemistry, College of Science, zhejiang university, hangzhou 310027, China. ) department of chemistry College of Science Zhejiang University Hangzhou 310029

Method for preparation of chitosan immobilized on silica gel(CTS silica) was described. The CTS silica was used as absorbent for the absorption of nickel in water. The results showed that this absorbent had relatively high selectivity and strong affinity to nickel. The maximum absorption capacity for nickel can reach 667 mg/g of chitosan. Factors that affect the absorption capacity, such as pH, ion strength and the presence of calcium, EDTA and the mechanism of absorption were discussed in detail. The absorbent can be regenerated with acid and reused for several times. The recovery rate for nickel can reach 99 99%. This absorbent filled in a column can be used in nickel removal from wastewater and drinking water.

关键词： immobilized chitosan nickel wastewater treatment

ON MULTIPLE POSITIVE SOLUTIONS FOR A NONLINEAR ELLIPTIC PROBLEM IN R^N

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Chinese Annals of Mathematics,Series B 2000年第3期21卷 351-358页

作者： yang HAITAO(department of Mathematics, zhejiang university, hangzhou 310027, China.) WU SHAOping(department of Mathematics, zhejiang university, hangzhou 310027, China.) department of Mathematics Zhejiang University Hangzhou 310027 China

By making use of Variational method, the authors obtain some results about existence of multiple positive solutions and their asymptotic behavior as the parameter →＋∞ for a semilinear elliptic problem in RN.

关键词： Critical point Asymptotic behavior Concentration

Preparation and Conductivity of Triheteropoly Tungstozincoaluminic Acid

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Rare Metals 2001年第4期20卷 221-223页

作者： Qingyin Wu department of chemistry, zhejiang university, hangzhou 310027, China 浙江大学浙江杭州 310027

The ternary undecatungstozincoaluminic heteropoly acid H-7[Al(H2O)ZnW11O39](.)12H(2)O was prepared by the ion exchanging-cooling method. The optimal proportion of solutions of the component elements and the pH of the synthesis reaction were given. The product was characterized by chemical analysis, potentiometric titration, IR, UV, XRD and TG-DTA. AC impedance measurement results show that its proton conductivity is 1.37x10(-4) S/cm at 18 degreesC.

关键词： heteropoly acid tungstozincoaluminic acid protonic conductivity