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Synthesis of 6-aryl substituted 3.(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3.4-b]-1,3.4-thiadiazoles

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Chinese Journal of Chemistry 1995年第5期13卷 448-453页

作者： ZHANG, Zi-Yi ZOU, NingNational Laboratory of Applied Organic Chemistry, department of Chemistry, lanzhou university, lanzhou, Gansu {3., China National Laboratory of Applied Organic Chemistry Department of Chemistry Lanzhou University Lanzhou Gansu 7S0000 China

In this paper , 10 novel 6-aryl-3.(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3. 4-b]-1,3.4-thiadiazoles have been synthesized by the condensation of 3.(5'-phenyl-2H-tetrazole-2'-methylene)-4-amino-5-mercapto-1,2,4-triazole with various aromatic carboxylic acids in the presence of phosphorus oxychloride. The structure of these compounds was determined by elemental analysis , UV, IR, 1H NMR and MS. Their spectral properties were also discussed.

关键词： S-triazolo[3.4-b]-1,3.4-thiadiazole synthesis spectral analysis

Studies on condensed heterocyclic compounds *** and antibacterial activity of 3.(4'-pyridyl)-6-aroylamino/arylamino-S-triazolo[3.4-b]-1,3.4-thiadiazoles

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Chinese Journal of Chemistry 1992年第1期10卷 59-64页

作者： ZHANG,Zi-Yi CHEN,Xin department of Chemistry,lanzhou university,lanzhou 73.000 department of Chemistry Lanzhou University Lanzhou 730000

3.(4′-Pyridyl)-4-amino-5-mercapto-1,2,4-triazole(1)reacted with aroyl isothiocyanates 2a-1 to yield twelve novel 3.(4′-pyridyl)-6-aroylamino-S-triazolo[3.4-b]-1,3.4-thiadiazoles,4a-1. Triethylamine was necessary for the condensation of 1 with phenyl isothiocyanate(3.to give 3.(4′- pyridyl)-6-phenylamino-S-triazolo[3.4-b]-1,3.4-thiadiazole(6).The structures were confirmed by the elemental and spectral *** antibacterial activity against ***,***,E. aerogenes and *** was observed preliminary.

关键词： Studies on condensed heterocyclic compounds II.Synthesis and antibacterial activity of 3 aroylamino/arylamino-S-triazolo[3.4-b pyridyl thiadiazoles II

Synthesis and Efficiency of a SphericalMacroporous Epoxy-dicyandiamide ChelateResin for Preconcentrating and SeparatingTrace Au, Hg, Pd and Ru from Samples

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Chemical Research in Chinese Universities 2001年第2期17卷 168-174页

作者： GONG Bo-lin, LI Xue-qiang and WANG Feng-rong (department of Chemistry, Ningxia university, Yinchuan 750021, China) CHANG Xi-jun (department of Chemistry,{3., lanzhou 73.000, China) 宁夏大学宁夏银川 750021 兰州大学甘肃兰州 730000

A novel spherical macroporous epoxy-dicyandiamide chelate resin was synthesized simply and rapidly from epoxy resin and used for the preconcentration and separation of trace amounts of Au (Ⅲ ), Hg (Ⅱ ), Pd (Ⅳ) and Ru (Ⅲ) ions from solution samples. The analyzed ions can be quantitatively concentrated by the resin at a flow rate of 2. 0 mL/min at pH 4, and can also be desorbed with 15 mL of 4 mol/L HCl + 0. 3.g thiourea from the resin column with recoveries of 96. 5%-99. 0%. After the chelate resin was reused for 7 times, the recoveries of these ions were still over 92%, and 400-1 000 times of excess of Fe(Ⅲ ), Al(Ⅲ ), Ni( II), Mn( Ⅱ ), Cr (Ⅲ ), Cu ( Ⅱ ), Cd (Ⅱ ) and Pb (Ⅱ ) caused little interference with the determination of these ions by an inductively coupled plasma optical emission spectrometer (ICP-OES ). The capacities of the resin for the analytes are in the range of 0. 3.~0. 92 mmol/g. The RSDs of the proposed method are in the range of 1. 1 % ~4. 0% for each kind of the analyzed ions. The recoveries of a standard added in real solution samples are between 96. 5% and 98. 5%, and the results for the analyzed ions in a powder sample are in good agreement with their reported values.

关键词： Concentration Separation Macroporous epoxy-dicyandiamide chelate resin Gold Mercury Palladium and ruthenium.

STUDY ON THE IMMOBILIZATION OF PAPAIN WITH A MACROPOROUS BEAD CARRIER OF COPOLYMER CONTAINING MONOMER UNITS OF NAMINOETHYL ACRYLAMIDE AND VINYL ALCOHOI

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Chinese Journal of Polymer Science 2000年第1期18卷 25-31页

作者： Yan-feng Li Jun-rong Li Lian-di Fu Yao-zeng Li department of Chemistry, lanzhou university, lanzhou 73.000, China Gansu Natural Energy Research Institute, lanzhou 73.000, China Gansu Provincial Institute of Drug Control, lanzhou 73.000, China 兰州大学甘肃兰州甘肃自然能源所甘肃兰州 730000 甘肃省药检所甘肃兰州 730000

A kind of macroporous bead carrier of copolymer containing monomer units of N-aminoethyl acrylamide and vinylalcohol was synthesized, i.e. the MR-AA carrier. Papain was immobilized on the carrier using glutaraldehyde as the couplingagent. The enzymatic activity of the immobilized papain was compared with free papain using casein as a substrate, and theeffects of glutaraldehyde concentration, pH, temperature, time and papain amount added on the activity recovery were alsoinvestigated. The results show that the MR-AA carrier contains reactive primary amine groups, hydrophilic amido links andhydroxyl groups, as well as macroporous structures based on its matrix (MR-AV matrix), furthermore, the activity recoveryof papain in the immobilization could reach 48%/～58%. In comparison with free papain, the resulting immobilized papainexhibits a remarkable thermostability and better reusability.

关键词： Immobilization Papain Proteolytic enzyme Macroporous bead carrier

On adjacent-vertex-distinguishing total coloring of graphs

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Science China Mathematics 2005年第3期48卷 289-299页

作者： ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang College of Mathematics and Information Science, Northwest Normal university, lanzhou 73.070, China department of Computer, lanzhou Normal College, lanzhou 73.070, China Institute of Applied Mathematics, lanzhou Jiaotong university, lanzhou 73.070, China College of Information and Electrical Engineering, lanzhou Jiaotong university, lanzhou 73.070, China Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, China College of Mathematics and Information Science Northwest Normal University Lanzhou China department of Computer Lanzhou Normal College Lanzhou China Institute of Applied Mathematics Lanzhou Jiaotong University Lanzhou China College of Information and Electrical Engineering Lanzhou Jiaotong University Lanzhou China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number... 详细信息

关键词： graph, proper total coloring, adjacent-vertex-distinguishing total coloring, adjacent-vertex-distinguishing total chromatic number.

Spectrofluorimetric determination of terbium with terephthalic acid

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Rare Metals 2002年第4期21卷 255-259页

作者： ZHAO Guohu and ZHAO JunBasic Science department, Gansu Agricultural university, lanzhou 73.070, China Basic Science department Gansu Agricultural University Lanzhou 730070

A Spectrofluorimetric method has been developed for the determination ofterbium(Ⅲ) based on the formation of a complex with terephthalic acid [benzene-1, 4-dicarboxylicacid (TPA)] in slightly acidic aqueous solution in the presence of gelatin. Terbium ion can form astable complex with TPA with the stoichiometry of 1:2. The best excitation and maximum emissionwavelengths are observed at 260 nm and 545 nm, respectively. The fluorescence intensity of terbiumcomplex gets the strongest within 20 min and remains stable up to 10 h, and it is proportional toterbium(Ⅲ) concentration in the range of 4.0x10^(-5)-1.6x10^(-7) mol·L^(-1) under the optimumconditions. The fluorescence system has good selectivity, sensitivity and stability. The relativestandard deviation is still within +-4% in the presence of 1200-fold amounts of the other lanthanideions when the concentration of terbium(Ⅲ) is 1.0x10^(-6) mol·L^(-1) and common co-existing ionshardly interfere the determination. It has been applied to the direct fluorimetric determination oftrace terbium (Ⅲ) in rare earth ores and oxides.

关键词： terbium spectrofluorimetry terephthalic acid gelatin

Aggregation of 1,3.di(a-naphthyl)propane and di(a-naphthylmethyl)ethet in aqueousbinary solvents

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Chinese Journal of Chemistry 1990年第4期8卷 375-383页

作者： LEI, Xue-Gong LIU, You-Cheng department of Chemistry, lanzhou university, lanzhou 73.000 department of Chemistry Lanzhou University Lanzhou 730000

The UV absorption and fluorescence spectra of 1,3.di (α-naphthyl) propane (1), di (α- naphthylmethyl) ether (2), and α-methylnaphthalene (3. in aqueous methanol, ethanol, and DMSO were recorded as a function of Φ value (fraction of water in binary solvents). The existence of two sta- tes, a metastable state (defined as m) and a stable stationary state (defined as s), of molecules 1 as well as 2 in the above cosolvents at high Φ was shown by the contrary fluorescence excimer to monomer intensity (Ie/Im)vs. Φ relationships of the samples prepared with different processes. On the basis of the Φ value, substrate concentration, and the temperature dependence of the UV spectra. fluores- cence excitation and emission spectra, the chromophores of 1, 2 show the formation of aggregates in ground state at high Φ owing to the hydrophobic interaction. The m states consist of a supersaturated solution with aggregates, whereas the s states are suspended microcrystals or micro-oil-droplets with aggregates. The conformations of the molecules in the aggregates were discussed. Single crystal X-ray structure of 2 is reported.

关键词： a-naphthylmethyl)ethet in aqueousbinary solvents Aggregation of 1,3.di a-naphthyl)propane and di

Two New Iridoid Glycosides from Caryopteris mongholica

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Chinese Chemical Letters 2000年第4期11卷 319-322页

作者： Yong Hong ZHANG Dong Liang CHENG (department of Chemistry, National Laboratory of Applied Organic Chemistry, lanzhou university, lanzhou 73.000) department of Chemistry Natl. Lab. of Appl. Organ. Chemistry Lanzhou University Lanzhou 730000 China

Two new iridoid glucosides were isolated from the whole plant of Caryopteris mongholica Bunge. On the basis of chemical and spectral evidence, they were determined as 8-acetyl-6'-O-(p-coumaroyl)harpagide and 6'-O-(p-c... 详细信息

关键词： Caryopteris mongholica verbanaceae 8-acetyl-6 '-O-(p-coumaroyl)harpagide 6 '-O-(p-coumaroyl)antirrinoside

SYNTHESIS, CHARACTERIZATION OF 2-[2-(3.NITRO-4-METHOXYLPHENYL) VINYLI-1-METHYLPYRIDINIUM PENTA AND HEXANITRATO RARE EARTH(Ⅲ) COMPLEXES

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Chinese Chemical Letters 1996年第1期7卷 89-90页

作者： Huan Wang JING Zi Jie HOU Shu Ying CHEN Du LI(department of Chemistry lanzhou university, lanzhou 73.000) department of Chemistry Lanzhou University Lanzhou 730000

The bile complexes have been Synthesised by the reaction of rare earth nitrate with 2-[2-3.nitro- 4-methoxylphenyl) vinyl ]-1-methylpyridinium nitrate in ethanol solution and have been characterized by IR. UV and 1H NMR spectre TG-DTA, molar conductance and X-ray powder diffraction . The results show that the Crystal form of Nd complex containing one molecular water as a ligand is eleven coordinated and is different from the others.

关键词： VINYLI-1-ME CHARACTERIZATION OF 2 NITRO-4-METHOXYLPHENYL