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Studies on Single-electron Oxidation of N-Alkyl-p-Phenylenediamines and Benzidines in Aqueous Acetonitrile by Cyclovoltammetry and ESR Spectroscopy

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chemical research in chinese Universities 1988年第4期 24-31页

作者： Zhang Fa, Gao Zhongli and Liu Youcheng(Department of chemistry, Lanzhou university, Lanzhou)Chen Wei(Instrumental Analysis and research center of Lanzhou university,Lanzhou)

It is demonstrated by cyclovoltammetry and ESR spectroscopy that N,N,N,’N,’-tetramethyl; tetraethgl, tetra-n-propyl, tetra-n-butyl-p-phenylenediamine and tetraethyl, tetra-n-propyl-p-benzidine undergo deprotonat ion and two consecutive single electron transfer step CE reaction at electrode in aqueous acetonitrile with the corresponding radical cations as the intermediate. The bivalent cations produced at the electrode react not only with hydroxyl anion in the medium to give quinone but also with the N-alkyl-p-phenylene-diamines or benzidines to produce the corresponding radical cations.

关键词： Cyclovoltammetry ESR N-alkyl-p-phenylenediamine N-alkyl-p-benzidine Electron transfer

Atomic Emission Spectrometry of Inductively Coupled Plasma with Sample Introduction by Electrothermal Vaporization

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chemical research in chinese Universities 1991年第1期7卷 27-31页

作者： Huang Min , Jiang Zucheng Zeng Yun’ e (Department of chemistry, Wuhan university, Wuhan) Present address, center of Material research and Testing, Wuhan university of Technology, Wuhan. To Whom correspondence should be addressed.

A system is described in which a graphite furnace electrothermal vaporization device is employed for the introduction of microlitre liquid sample into an inductively coupled argon plasma. The technique provides a picogram detection limit and an adequate precision with a relative standard deviation of 4%. Mechanism of analyte condensation in transport process is explored. As an application, the technique combined with DDTC/CCl4 extraction is used to enrich and determine non- rare earth impurities in highly pure La2O3.

关键词： Electrothermal sample introduction Inductively coupled plasma Optical emis-sion spectrometry

Synthesis and Molecular Structure of Aluminum and Zinc Compounds Supported by β-Enaminoketonato Ligands

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Synthesis and Molecular Structure of Aluminum and Zinc Compo...

Effects of Various Dopants on Solitons in Polyacetylene

中国化学会第四届有机化学学术会议

作者： HAO, Hai-Jun CHENG, Biao-Hua TANG, Liang-Fu ZHANG, Fa-Liang TANG, Liang-Fu (Key Laboratory of Science and Technology of Controllable chemical Reactions, beijing university of chemical Technology, beijing 100029) (State Key Laboratory of Elemento-Organic chemistry, Nankai university, Tianjin 300071)

＜正＞In recent years the β-enaminoketonato ligands were reported to stabilize early and late transition metals showing a variety of applications. However, little attention has been drawn to the corresponding main group metal compounds. We are interested in aluminum and zinc compounds of this type of ligands, for they are potential catalysts toward the ring opening polymerization of bio-renewable lactide （LA） to produce the biodegradable polylac-tide （PLA）. Reactions of ArN=C（Me）C=C（R）OH （Ar=2,6-Me2C6H3, i-Pr2C6H3;R=Me, C6H5, ferrocenyl） with

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来源： cnki会议评论

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chemical research in chinese Universities 1991年第4期7卷 231-235页

作者： Wang Rongshun and Huang Zhonghao (Department of chemistry, Northeast Normal university, Changchun)Meng Lingpeng (Department of chemistry, Hebei Teacher’s college, Shijiazhuang)

The effects of various dopants on solitons in polyacetylene were studied by using CNDO/2 level semiempirical quantum chemical method. The width of solitons is reduced when dopant is present, and the charge density wave(CDW) is further gathered on the carbon atom in soliton center. The effects of p-type of dopants are greater than those of n-type of ones. The charge transfer in doped polyacetylene can be achieved by the propagation of CDW along the chain. The conductivity of doped polyacetylene is proportional to the quantity of charge transfer between dopant and polyacetylene chain.

关键词： Polyacetylene Soliton Charge density wave Dopant

OPTIMAL SCHEME FOR SEQUENTIAL COMPUTATIONS OF F_m(z) INTEGRALS IN AB INITIO CALCULATIONS----COMBINATORY USE OF UPWARD AND DOWNWARD RECURSIONS

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chemical research in chinese Universities 1986年第1期4卷 76-84页

作者： Liao Muzhen,and Wu Guoshi,Chen Kaixian Liu Honglin and Chen Nianyi(Department of chemistry and chemical engineering,Tsinghua university,beijing)(Shanghai Institute of Materia Medica,Academia Sinica,Shanghai) (Shanghai Institute of Metallurgy,Academia Sinica,Shanghai)

The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been *** traditional viewpoint to negate the applicability and reliability of upward recursive formula in principle is *** optimal scheme of upward-and downward-joint recursions has been developed for the sequential F(z) *** additional accuracy is needed with the fundamental term of recursion because the absolute error of Fn(z) always decreases with the recursive *** scheme can be employed in modifying any of existent subprograms for Fn *** the case of p-d-f-and g-type Gaussians,combining this method with Schaad's formulas can reduce,at least,the additive operations by a factor 40%;the multiplicative and exponential operations by a factor 60%.

关键词： COMBINATORY USE OF UPWARD AND DOWNWARD RECURSIONS INTEGRALS IN AB INITIO CALCULATIONS OPTIMAL SCHEME FOR SEQUENTIAL COMPUTATIONS OF F_m down AB

Synthesis, Characterization and Structure of 3d Metal Nitrate Complexes with 1,8-Naphthyridine-N-Oxide

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chemical Journal of chinese Universities 1988年第3期 17-23页

作者： Tan Minyu, Gan Xinmin, Tang Ning and Zhang Wenjun (Department of chemistry, Lanzhou university, Lanzhou) Wang Xin Zhu Yin (Analysis and research center of Lanzhou university, Lanzhou)

The complexes of 3d metal（Cr, Mn, Fe, Co, Ni, Cu, Zn） nitrates with 1 , 8-naphthyridine-N-oxide （NAPYO） were synthesized. The melting points and solubilities of the new complexes were determined and all the complexes were characterized by elemental analyses, IR spectra, UV spectra and molar conductance. The structures of both nickel complex and copper complex were determined by X-ray single crystal diffraction analyses.

关键词： 1 8-Naphthyridine-N-oxide 3d metal nitrace complex structure

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黄芩化学成分及炮制学研究

天然产物研究与开发 2004年第6期16卷 575-580页

作者：温华珍肖盛元王义明罗国安清华大学化学系

黄芩是一味常用中药 ,在临床上使用频率较高。本文概述了黄芩的化学成分研究概况 ,并对其炮制工艺和炮制品的药理研究作了简要介绍。

关键词：黄芩化学成分炮制工艺中药药理

Studies on Organo-Phosphorus, -Arsenic and -Antimony Polytungstates and Polymolybdates(IX )——Preparation and Properties of o-Aminophenylarsenic Polymolybdates

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chemical research in chinese Universities 1990年第3期6卷 172-176页

作者： Liu Benyao, Xie Gaoyang and Yihtong Ku(Gu Yidong) (Department of chemistry, Fudan university, Shanghai)Wang Xin (center of Analysis and Measurement, Lanzhou university, Lanzhou)

In order to investigate the influence of organic groups on the types of organoarsenic polymolybdates, o-nitrophenylarsonic acid was reduced to o- aminophenylarsonic acid and then it reacted with sodium molybdate at pH = 3;. Three new salts were prepared and characterized:（ 1 ）（CN3H6）4[（o-NH2C6H4As）2Mo6O24], （ 2 ） Cs4[（o-NH2C6H4As）2Mo6O24], （3） [（CH3）4N]4[（o-NH2C6H4As）2Mo6O24].2H2O. The IR, UV spectra, thermal properties and electrochemical behaviors are reported. It is strange enough that when the o-nitro group was reduced to o-amino group, [（RAs）2Mo6O24]4- type of complexes was formed.

关键词： o-Aminophenylarsonic acid Polymolybdates Polytungstates

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我国城市污泥中含氮有机污染物的初步研究

生态学杂志 2004年第3期23卷 76-80页

作者：蔡全英莫测辉赖坤容曾巧云吴启堂王伯光李海芹华南农业大学资源环境学院广州510642 长安大学雁塔校区应用化学系西安710054 广州市环境监测中心站广州510030

应用GC/MS联机检测技术对 11个城市污泥中 6种含氮有机污染物进行分析。结果表明 ,城市污泥中 6种含氮有机化合物的总含量在 0 0 87～ 2 6 4 38mg·kg-1,高低依次为兰州污泥 >北京污泥 >无锡污泥 >大埔 (香港 )污泥 >沙田 (香港 )污... 详细信息

应用GC/MS联机检测技术对 11个城市污泥中 6种含氮有机污染物进行分析。结果表明 ,城市污泥中 6种含氮有机化合物的总含量在 0 0 87～ 2 6 4 38mg·kg-1,高低依次为兰州污泥 >北京污泥 >无锡污泥 >大埔 (香港 )污泥 >沙田 (香港 )污泥 >佛山污泥 >广州污泥 >元朗 (香港 )污泥 >珠海污泥 >西安污泥 >深圳污泥。不同化合物在各城市污泥中的含量和分布特征有明显差异。硝基苯类的含量较高 ,胺类的含量较低。兰州污泥中含氮有机化合物的含量普遍较高 ,其次是无锡污泥、北京污泥和大埔污泥。污泥中含氮有机化合物的种类和含量与污水来源、污水处理方式、污泥类型。

关键词：城市污泥有机污染物含氮有机化合物