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THE DEFECT ITERATION OF THE FINITE ELEMENT FOR ELLIPTIC BOUNDARY VALUE PROBLEMS AND PETROV-GALERKIN APPROXIMATION

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Journal of Computational Mathematics 1998年第2期16卷 152-164页

作者： Gao, jb Yang, YD Shih, TM Huazhong Univ Sci & Technol Dept Math Wuhan 430074 Peoples R China Guizhou Normal Univ Dept Math Guiyang 550001 Peoples R China Hong Kong Polytech Univ Dept Math Appl Hong Kong Peoples R China

In this paper we introduce a Petrov-Galerkin approximation model to the solution of linear and semi-linear elliptic boundary value problems in which piecewise quadratic polynomial space and piecewise linear polynomial space are used as the shape function space and the test function space, respectively. We prove that the approximation order of the standard quadratic finite element can be attained in this Petrov-Galerkin model. Based on the so-called 'contractivity' of the interpolation operator, we further prove that the defect iterative sequence of the linear finite element solution converge to the proposed Petrov-Galerkin approximate solution.

关键词： Petrov-Galerkin approximation defect iteration correction interpolation operator

Notes on the genus Entoloma *** the Northwest of the Iberian Peninsula(Ⅺ):a new species in subgenus Entoloma

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Studies in Fungi 2021年第1期6卷 64-70页

作者： Blanco-Dios jb Centro de Formación e Experimentación Agroforestal de Lourizán.Consellería do Medio Rural.Xunta de Galicia.P.O.Box 127.36003 Pontevedra Spain

Entoloma cedeirense,a new species in subgenus Entoloma,is described from in Galicia(NW of Spain).A detailed macro and micromorphological descriptions,drawings and a discussion with closely related taxa of subgenus Ent... 详细信息

关键词： Agaricales Basidiomycota Entolomataceae Spain Taxonomy

Notes on the genus Arrhenia(I):Arrhenia pontevedrana,*** ***(Agaricales,Basidiomycota),from the northwest of the Iberian Peninsula

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Studies in Fungi 2019年第1期4卷 185-191页

作者： Blanco-Dios jb Centro de Formación e Experimentación Agroforestal de Lourizán.Consellería do Medio Rural.Xunta de Galicia.P.O.Box 127.36003 Pontevedra Spain

Arrhenia pontevedrana is described as a new species to science from Galicia(NW of Iberian Peninsula)based on morphological characteristics.A detailed description of basidiomata and microstructures of this species and a comparison with its morphologically closely related taxa are *** subglobisemen is recorded for the first time from the Iberian *** new combination Arrhenia kuhnerii is also proposed.

关键词： Biodiversity Spain Taxonomy Tricholomataceae

Kinetic Study on Horseradish Peroxidase Interacting with Cyclodextrin

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Chinese Chemical Letters 2000年第8期11卷 721-724页

作者： Chen, jb Xia, CG Ben Li, S Chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Oxo Synth & Select Oxidat Lanzhou 730000 Peoples R China

The catalyst reactivity of Horseradish peroxidase was enhanced in the presence of beta-cyclodextrin. During this course, beta- cyclodextrin played a role of stabilizing the intermediates of HRP. The results have been ... 详细信息

关键词： horseradish peroxidase beta- cyclodextrin compound kinetics

A novel solid state Michael addition reaction of N-heterocyclic compounds containing active C-H bond

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Chinese Journal of Chemistry 1996年第5期14卷 421-427页

作者： Li, XL Wang, YM Tian, B Meng, jb NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

In this paper, a novel solid state Michael-type addition reaction of N-heterocyclic compounds containing the active-CH group was investigated. 3-Methyl-1-phenyl-5-pyrazolone (MPP) and indole (In) reacted with 4-arylmethylene-3-methyl-1-phenyl-5-pyrazolone (1) in the solid state at room temperature to give the corresponding adducts, aryl-4,4'-bis(5-hydroxy-3-methyl-1-phenyl-pyrazolyl) methane (2a-n) and 1-aryl-1-(5'-hydroxy-3'-methyl-1'-phenyl-4'-pyrazolyl)-1-(3 ''-indolyl) methane (3a-n), respectively. This is a feasible method for preparing the compound which contains two heterocyclic groups on the same carbon.

关键词： indole pyrazolone Michael addition solid state reaction

Spatial distribution of copper content in sediments of the Yangtze River system

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Chinese Science Bulletin 1997年第15期42卷 1294-1297页

作者： Zhang, CS Zhang, S He, jb State Key Laboratory of Resources and Environment Information System China Department of Chemical Geography Institute of Geography Chinese Academy of Sciences Beijing China

THE spatial distribution pattern of an element content is controlled by various geochemical pro-cesses. Studies on the spatial pattern are beneficial to further analysis on the factors. As a re-sult, our knowledge about the geochemical processes is enriched. At the same time, describingthe spatial patterns quantitatively with some indices is one way from qualitative to quantitativeanalysis.

关键词： geostatistics variogram Kriging copper.

The Synthesis of a Novel Lignan

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Chinese Chemical Letters 2000年第11期11卷 971-974页

作者： Qi, XX Chang, jb Guo, RY Chen, RF Zhengzhou Univ Dept Chem Zhengzhou 450052 Peoples R China Henan Acad Sci Henan Inst Chem Zhengzhou 450002 Peoples R China

A short convenient synthesis of a novel lignan, 2-(3',4',5'-trimethyoxyphenyl)-1,3-dimethyl-6,7,8-trimethoxy- naphthalene has been accomplished by the condensation of key intermediates, 3,4,5-trimethoxybenzyl methyl k... 详细信息

关键词： UV KBr IR The Synthesis of a Novel Lignan EtOH

Synthesis and photochromism of dimers of 4,5- diaryl-2-(2,5-dimethylthiophen-3-yl)imidazolyl

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Chinese Journal of Chemistry 1997年第6期15卷 553-555页

作者： Bai, JQ Han, XC Wang, YM Meng, jb Nankai Univ Dept Chem Tianjin 300071 Peoples R China

4,5-Diphenyl, 4,5-di(4-methylphenyl), 4,5-di(4-methoxyphenyl)-2-(2,5-dimethylthiophen-3-yl)imidazoles were synthesized. Oxidation of the obtained imidazoles with potassium ferricyanide in water-alcohol solution of alkali gave the corresponding dimers. The structures were characterized by IR, H-1 NMR, mass spectroscopy and elemental analysis. The dimers showed photochromism in solution on irradiation.

关键词： synthesis imidazoles dimers photochromism

Solid state reaction of aromatic ketones with heteroaromatics

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Chinese Journal of Chemistry 1995年第6期13卷 520-524页

作者： Du, DM Meng, SM Wang, YM Meng, jb Zhou, XZ NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA YANBEI TEACHERS COLL DATONG 037000JILINPEOPLES R CHINA

The solid state reactions of p-nitroacetophenone, acetyl-ferrocene with indole were catalyzed by anhydrous zinc chloride or aluminum chloride, and gave exclusively the 1:2 condensation products. The solid state condensation of aromatic ketones with 1-phenyl-3-methyl-5-pyrazolone was also investigated, and the 1:1 and 2:1 condensation products were obtained. The structures of eleven new products were determined by IR, MS, H-1 NMR and elemental analysis.

关键词： solid state reaction aromatic ketone indole 1-phenyl-3-methyl-5-pyrazolone