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Microwave-assisted Solventless Biginelli Reaction Catalyzed by Montmorillonite Clay-SmCl_3 6H_2. System

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Chinese Chemical Letters 2003年第10期14卷 993-995页

作者： Yu Xia LI, wei Liang bao {2. of Chemistry, zhejiang university, Xi Xi Campus, hangzhou 31002. department of Chemistry Zhejiang University Xi Xi Campus Hangzhou 310028

4-Aryl/alkyl-3,4-dihydro-2.1H)-pyrimidone esters and 5-acetyl-4-aryl/or alkyl-6-methyl- 3, 4-dihydropyrimidin-2.l)-ones were synthesised efficientiy using montmorillonite clay- SmCl3 6H2. system promoted by microwave ... 详细信息

关键词： Microwave samarium trichloride montmorillonite Biginelli reaction pynmidone.

UNIQUENESS OF OPTIMAL QUADRATURE FORMULAS FOR W_1~m AND THE FUNDAMENTAL THEOREM OF ALGEBRA FOR PERIODIC MONOSPLINES

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Chinese Annals of mathematics,Series B 1990年第4期11卷 426-437页

作者：黄达人房艮孙 department of mathematics Zhejiang UniversityHangzhouZhejianghina. department of mathematics Beijing Normal UniversityBeijingChina.

This paper proves that the optimal quadrature formulas of type（r1,…rn） for Wm1 isunique,and the extremal function is characterized by its oscillatory *** theother hand,the fundamental theorem of algebra for periodi... 详细信息

关键词： quadrature oscillatory algebra formulas uniqueness whenever polynomial lemma 七势 isola

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, {2. university, hangzhou 31002., 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.

THE FLOW IN ROTATING CURVED CIRCULAR PIPE

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Journal of Hydrodynamics 2000年第1期12卷 108-116页

作者： Zhang Jin suo, Shen Xin rong, Zhang Ben zhao department of Mechanics, {2. university, hangzhou 31002., P.R.china zhejiang Univ Hangzhou China

The combined effects of the system rotation (Coriolis force) and curvature (centrifugal force) on the flow in rotating curved circular pipe with small curvature are examined by perturbation method. A second order perturbation solution is presented. The secondary flow structure and the primary axial velocity distributions are studied in detail. The loops of the secondary flow are more complex than those in a curved pipe without rotation or a rotating straight pipe. Its numbers depend on the body force ratio F which represents the ratio of the Coriolis to the centrifugal force. The maximum of the axial velocity is pushed to either outer bend or inner bend, which is also determined by F. The results are confirmed by the results of other authors who studied the same problem by different methods.

关键词： secondary flow curved pipe perturbation method

CHEMOENZYMATIC SYNTHESIS OF BIODEGRADABLE POLY(1’-O-VINYLADIPOYL-SUCROSE)

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Chinese Journal of Polymer Science 2002年第6期20卷 579-584页

作者： De-shui Lu Qi Wu Xian-fu Lin department of Chemistry zhejiang {2. hangzhou 31002., china zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

A novel polymer containing the sucrose group was synthesized by radical polymerization from an enzymatically prepared monomer, 1'-O-vinyladipoyl-sucrose (VAS). Transesterification reaction of sucrose with divinyl adipate in anhydrous pyridine catalyzed by an alkaline protease from Bacillus subtilis at 60degreesC for 7 days gave VAS (yield 55%) without any blocking/deblocking steps. The vinyl sucrose ester could be polymerized with potassium persulfate and H2.2.as initiator to give poly(1'-O-vinyladipoyl-sucrose) with M-n = 33,000 and M-w = 53,2.0, M-w/M-n = 1.61. The polymer was biodegradable. After 6 days in aqueous buffer (pH 7), this alkaline protease could degrade poly(1'-O-vinyladipoyl-sucrose) to M. of ca. 1080, M-w/M-n = 3.30 (37degreesC), and M-n of ca. 52.0, M-w/M-n = 2.44 (4degreesC). The polymer containing the sucrose branch would be a functional material in various application fields.

关键词： divinyladipate sucrose alkaline protease polymerization biodegradation

A Bregman-Style Improved ADMM and its Linearized Version in the Nonconvex Setting:Convergence and Rate Analyses

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Journal of the Operations Research Society of china 2024年第2期12卷 298-340页

作者： Peng-Jie Liu Jin-bao Jian Hu Shao Xiao-Quan Wang Jia-wei Xu Xiao-Yu Wu School of mathematics Jiangsu Center for Applied MathematicsChina University of Mining and TechnologyXuzhou 221116JiangsuChina School of mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006GuangxiChina department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina School of mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina

This work explores a family of two-block nonconvex optimization problems subject to linear *** first introduce a simple but universal Bregman-style improved alternating direction method of multipliers(ADMM)based on the iteration framework of ADMM and the Bregman ***,we utilize the smooth performance of one of the components to develop a linearized version of *** to the traditional ADMM,both proposed methods integrate a convex combination strategy into the multiplier update *** each proposed method,we demonstrate the convergence of the entire iteration sequence to a unique critical point of the augmented Lagrangian function utilizing the powerful Kurdyka–Łojasiewicz property,and we also derive convergence rates for both the sequence of merit function values and the iteration ***,some numerical results show that the proposed methods are effective and encouraging for the Lasso model.

关键词： Nonconvex optimization Alternating direction method of multipliers Kurdyka-Lojasiewicz property Convergence rate

Critical Range of Soil Boron for Prognosis of Boron Deficiency in Oilseed Rape

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Pedosphere 2001年第3期11卷 283-288页

作者： wei YOUZHANG department of Soil Science and Agricultural Chemistry, {2. university, hangzhou 31002. (china) 浙江大学浙江杭州 310029

Relationships between seed yields of oilseed rape (Brassica napus L.) and extractable boron concentrations in three soil layers (A, P and W) were investigated through ten experiments on three types of soils (Alluvic Entisols, Udic Ferrisols and Stagnic Anthrosols) in northern, western and middle zhejiang Province. Among several mathematical models used to described the relationships, the polynomial equation, y = a + bx + cx2.+ dx3, where y is the yield of oilseed rape seed and x the extractable boron concentration in P layer of soil, was the best one. The critical range of the concentrations corresponding to 90% of the maximum oilseed rape yield was 0.40-0.52.mg kg-1. The extractable boron concentration of the P layers of the soils was the most stable. The critical range determined was verified through the production practices of oilseed rape in zhejiang and Anhui provinces.

关键词： boron deficiency critical range oilseed rape soil layer

On the Cardinal Spline Interpolation Corresponding to Infinite Order Differential Operators

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Acta Mathematica Sinica,English Series 1994年第3期10卷 315-324页

作者： Chen Dirong department of {2. Beijing Normal university Beijing,100875 and Center for Mathematical Sciences zhejiang university hangzhou,31002. china 1. department of mathematics Beijing Normal University 100875 Beijing 2. Center for Mathematical Sciences Zhejiang University 310027 Hangzhou China

This paper discusses some problems on the cardinal spline interpolation correspond- ing to infinite order differential *** remainder formulas and a dual theorem are es- tablished for some convolution classes,where the kernels are PF ***,the exact error of approximation of a convolution class with interpolation cardinal splines is determined. The exact values of average n-Kolmogorov widths are obtained for the convolution class.

关键词： Math On the Cardinal Spline Interpolation Corresponding to Infinite Order Differential Operators lim Chen 卜成

Ground and Excited States of Bipolarons in Two and Three Dimensions

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Communications in Theoretical Physics 2007年第7期48卷 169-174页

作者： RUAN Yong-Hong CHEN Qing-Hu department of Physics,zhejiang {2.,hangzhou 31002.,china department of Physics Zhejiang University

The properties of large bipolarons in two and three dimensions are investigated by averaging over therelative wavefunction of the two electrons and using the Lee-Low-Pines-Huybrechts variational *** ground-state(GS)and excited-state energies of the Frhlich bipolaron for the whole range of electron-phonon coupling constantscan be *** energies of the first relaxed excited state(RES)and Franck-Condon(FC)excited state of thebipolaron are also *** is found that the first RES energy is lower than the FC state *** comparisonof our GS and RES energies with those in literature is also given.

关键词： bipolaron ground-state energy excited-state energy Lee-Low-Pines-Huybrechts variational method