检索结果-南通市图书馆

Heterogeneous reactions on the surface of fine particles in the atmosphere

在线全文

cnki会议

学校读者我要写书评

暂无评论

chinese Science Bulletin 2003年第21期48卷 2267-2276页

作者： DING Jie & ZHU Tong State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental sciences, Peking university, beijing 100871, China Correspondence should be addressed to Zhu Tong (e-mail:tzhu@ ***) State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University China

Fine particles play an important role in the atmosphere. Research on heterogeneous reactions on the surface of fine particles is one of the frontier areas of atmospheric science. In this paper, physical and chemical characteristics of fine particles in the atmosphere and the interactions between trace gases and fine particles are described, methods used in heterogeneous reactions research are discussed in detail, progress in the study of heterogeneous reactions on the surface of fine particles in the atmosphere is summarized, existing important questions are pointed out and future research directions are suggested.

关键词：细微颗粒大气科学多相反应空气动力学

SURFACE MODIFICATION OF CaCO_3 WITH DENDRITIC CARBOXYLIC ACIDS

在线全文

学校读者我要写书评

暂无评论

chinese Journal of Polymer Science 2002年第3期20卷 231-235页

作者： Zhao-xia Guo Jian Yu Institute of Polymer Science and Engineering Department of Chemical Engineering Tsinghua university beijing 100084.China Tsing Hua Univ Dept Chem Engn Inst Polymer Sci & Engn Beijing 100084 Peoples R China

Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at thefocal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO;and thedendritic modifier was proven by IR and mass spectroscopy of the modified CaCO;after thorough extraction withdichloromethane. The amount of tightly bonded organic modifier was estimated by TGA. It was shown that the amount ofbonded molecules decreased with increasing generation number due to the larger number of branches. Compared tounmodified CaCO;, the modified CaCO;possess different dispersibility in water and in organic solvents.

关键词： calcium carbonate surface modification polyether dendrimer dendritic carboxylic acid

Prokaryotic Expression of a Strain Anti-Myxobolus Rotundus Recombinant Scfv

在线全文

学校读者我要写书评

暂无评论

Prokaryotic Expression of a Strain Anti-Myxobolus Rotundus R...

12th International Congress of Protozoology

作者： J.Y. Zhang, J.G Wang. Y.S. Wu, M. Li, A.H Li State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, chinese academy of sciences,Wuhan, Hubei 4.0072, PR China Institute of Tropical Medicine, The Southern Medical university, Guangzhou, Guangdong 510515, PR China {4. School of chinese academy of sciences, beijing 100039, P. R. China

＜正＞In our previous work, a strain specifically anti-Myxobolus rotundus ScFv, pCAN-6H9 was isolated from the constructed phage display ScFv library against M. rotundus infecting allogynogenetic crucian carp, Carassius auratus auratus gibelio. In the present work, the encoding gene of pCAN-6H9 was cloned into pET-23（a） to construct recombinant pET-6H9. After induction with 1mM IPTG for 8h, the recombinant fused protein was detected in the culture supernatant and peripheral cavity by SDS-PAGE and

关键词：

Mineralogical and geochemical evidence for coupled bacterial uranium mineralization and hydrocarbon oxidation in the Shashagetai deposit,NW China

在线全文

cnki会议

学校读者我要写书评

暂无评论

Mineralogical and geochemical evidence for coupled bacterial...

中国科学院地质与地球物理研究所2006学术年会

作者： Chunfang Cai~1,Hailiang Dong~2,Hongtao Li~1,Xinjian Xiao~3,Guanxi Ou~3, Chunming Zhang~4.1 Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,chinese academy of sciences,P.O. Box 9825,Beitucheng Xilu No.19,beijing 100029,P.R.China 2 Department of Geology,Miami {4.,Oxford,OH 4.056,USA 3 beijing Research Institute of Uranium Geology,beijing 100029,P.R.of China 4.Department of Geochemistry,Yangtze {4.,Jingzhou,Hubei 4.4.23,PR China

Unusual mineral structures have recently been found in a sandstone-hosted roll-type uranium deposit in the Middle Jurassic Zhiluo Formation in the Shashagetai deposit,the northern Ordos basin,NW *** structures possess a chemical composition and crystal structure characteristic of mineral coffinite[(USiO)](OH)],which occurs as nanoparticles with size ranging from 5 to *** structures are interpreted to be fossilized microorganisms,based on mineralogical biosignatures including morphology,size,occurrence of biogenic coffinite as nano-crystals,and biological elements such as *** intimate intergrowth of coffinite with secondary pyrite of bacterial origin,as defined by lowδS values,and calcite cements with petroleum-derived carbon supports its biogenic *** inclusions in the host sandstone are characterized by abundant n-alkanes,slightly increased Pr/nC and Ph/nC ratios,significant amounts of demethylated hopanes and tricyclic terpanes,and the existence of unresolved complex *** characteristics are interpreted to be a result of mixing of an earlier,heavily degraded oil with a later charged fresh oil;subsequently the oils were slightly *** lines of evidence lead to the proposal that the reduction of sulfate and oxidization of petroleum are likely synchronous with reduction of hexavalent[U(Ⅵ)]to tetravalent[U(Ⅳ)]uranium by sulfate-reducing bacteria(SRB).The discovery of a natural association of microorganism-like structures,a uranium mineral,and biodegraded petroleum has implications for uranium biomineralization and fossil fuel exploration.

关键词： uranium deposit anaerobic petroleum oxidation sulfate-reducing bacteria nanoparticle microfossil sulfur isotopes

The mechanism of the electrochemical reduction of 5-nitrouracil

在线全文

cnki会议

学校读者我要写书评

暂无评论

chinese Journal of Chemistry 1988年第2期6卷 95-101页

作者： HU Yu HU Zhi-Bin WANG Zheng-Hao Department of Chemistry,beijing Normal university,beijing Department of Chemistry Beijing Normal University Beijing

The electrochemical reduction of 5-nitrouracil （5NU） has been investigated on Ag-Hgcathode in DMSO by cyclic voltammetry and controlled potential electrolysis,in combination withUV and ESR *** results showed that 5NU proceeds in a four-electron reduction andsimultaneously participates in the reaction as a proton *** a more negative potential,the 5NUanion （5NU） thus formed is reduced further through a one-electron process to a dianion *** have been determined as aN=14.6 G,aH=5.2 G and g=*** radicaldecay process might be conjectured through protonization by accepting protons from 5NU,of whichthe rate constant k=52 M·s.

关键词： The mechanism of the electrochemical reduction of 5-nitrouracil

青少年及其家长应付方式、心理健康状况的相关研究

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

心理科学 2004年第5期27卷 1251-1253页

作者：周芹徐文艳北京中医药大学管理学院北京100029 香港中文大学社工系

研究者通过对 80 0名 1 2——— 1 6岁中学生及其家长的测试 ,比较了青少年及其家长应付方式、心理健康状况的异同和相关 ,结果表明 :1、中学生的积极、成熟应付方式和心理健康状况低于成年人 ;2、青少年的应付方式与其家长的应付方式... 详细信息

研究者通过对 80 0名 1 2——— 1 6岁中学生及其家长的测试 ,比较了青少年及其家长应付方式、心理健康状况的异同和相关 ,结果表明 :1、中学生的积极、成熟应付方式和心理健康状况低于成年人 ;2、青少年的应付方式与其家长的应付方式呈现出同质化的特点 ,观察、模仿家长是形成青少年应付方式的重要途径 ;3、“合理化”

关键词：青少年家长应付方式心理健康状况社会学习理论同质化

Distinguishing the authenticity of anti-freeze liquid and brake fluid by terahertz time-domain spectra technology

在线全文

学校读者我要写书评

暂无评论

Distinguishing the authenticity of anti-freeze liquid and br...

中国光学学会2010年光学大会

作者： ZHU Shou-ming 1,ZHAO Kun 1,2,4.TIAN Lu 1,ZHAO Song-qing 1,ZHAO Hui 1,BAO Ri-ma 1,MIAO Qing 1,ZHOU Qing-li 3,SHI Yu-lei 3,ZHAO Dong-mei 3,ZHANG Cun-lin 3 1.School of Science,China university of Petroleum,beijing 10224.,China 2.State Key Laboratory of Heavy Oil Processing,China university of Petroleum,beijing 10224.,China 3.beijing Key Laboratory for Terahertz Spectroscopy and Imaging,Key Laboratory of Terahertz Optoelectronics,Ministry of Education,Department of Physics,Capital Normal university,beijing 10004.,China 4.International Center for Materials Physics,chinese academy of sciences,Shenyang 110016,China.

Terahertz time-domain spectra （THz-TDS） technology is a new kind of coherent far infrared spectroscopy measurement technique based on the femtosecond *** optical property and spectroscopy of methanol,anti-freeze liquid and brake fluid are studied based on the THz-TDS in the terahertz *** whether methanol exists in anti-freeze liquid or brake fluid by Using THz-TDS technology is crucial to its *** room temperature,the time-domain spectra and the absorption spectrum in the 0.2-2.5 THz region of these samples are obtained in the environment full of *** Results show that methanol,anti-freeze liquid and brake fluid have significant different absorption spectra in this wave *** absorption peaks of methanol are located at 0.72 THz and 0.35 THz and the main absorption peaks of anti-freeze liquid and brake fluid are located at 0.62 ***-TDS Technology can distinguish minor differences in structure and can be applied to physical testing and *** provides a new experimental method for the identification of the organic chemical products and the study of spectrum more wide.

关键词： terahertz methanol anti-freeze liquid brake fluid

在线全文

cnki会议

学校读者我要写书评

暂无评论

控释氮肥溶出率的测定方法及应用研究

土壤肥料 2003年第6期 43-45页

作者：王新民魏志华马瑞霞中国科学院生态环境研究中心北京100085 安阳大学河南安阳455000

本文介绍了一种测定控释N肥溶出率的方法,并用该方法分别对尿素和11种控释N肥样品同时进行操作,比较尿素及11种控释N肥溶出率的大小,从中选出好的控释N肥品种。

关键词：控释氮肥溶出率测定方法应用尿素

聚硅氧烷包夹聚合硅基高效液相色谱固定相的表征及其色谱性能

在线全文

学校读者我要写书评

暂无评论

分析测试学报 2001年第5期20卷 34-37页

作者：杨瑞琴蒋生祥陈立仁中国人民公安大学侦查系北京100038 中国科学院兰州化学物理研究所分析测试中心甘肃兰州730000

利用元素分析、红外光谱、扫描电镜及汞压吸附法对制备的聚硅氧烷包夹硅基反相高效液相色谱固定相进行了表征 ,给出了该固定相的结构信息及其与色谱性能的关系 ;用滴定法测定了该固定相表面硅羟基数目 ;考察了该固定相对碱性化合物的分... 详细信息

利用元素分析、红外光谱、扫描电镜及汞压吸附法对制备的聚硅氧烷包夹硅基反相高效液相色谱固定相进行了表征 ,给出了该固定相的结构信息及其与色谱性能的关系 ;用滴定法测定了该固定相表面硅羟基数目 ;考察了该固定相对碱性化合物的分离性能 ;由表征和色谱性能考察结果可知 ,该固定相表面的羟基基本被覆盖 ,因此 ,可在碱性流动相中长期使用。

关键词：高效液相色谱固定相表征硅胶聚硅氧烷碱性化合物分离色谱性能