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science china Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2 & YIN Yingwu2,3 1. college of Chemistry & Environment Protection engineering, Southwest university for Nationalities, Chengdu 610041, china 2. TH-UNIS Insight Co., Ltd., beijing 100085, china 3. Key Laboratory of Bioorganic Phosphorus Chemistry & chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua university, beijing 100084, china 1. college of Chemistry & Environment Protection engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. Key Laboratory of Bioorganic Phosphorus Chemistry & chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2 h at 200℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

An experimental study of aero-optical aberration and dithering of supersonic mixing layer via BOS

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 81-94页

作者： ZHAO YuXin , YI ShiHe, TIAN LiFeng, HE Lin & CHENG ZhongYu college of Aerospace and material engineering, National university of Defense technology, Changsha 410073, china 1. college of Aerospace and material engineering National University of Defense Technology Changsha 410073 China

The optical performance of supersonic mixing layer is heavily deteriorated by the aero-optical aberration and dithering of coherent structures, but current measuring methods limit the spatiotemporal resolution in relevant studies. A high resolution whole-field aero-optical aberration and dithering measuring method based on the Background Orient Schlieren (BOS) technique was studied. The systematic structure, sensitivity and resolution of BOS are analyzed in this paper. The aero-optical aberration and dithering of streamwise structures in supersonic mixing layers were quantificationally studied with BOS. The aberration field of spanwise structures revealed the ribbon-like aberration structures, which heavily restrict the optical performance of a mixing layer. The quantifications of aero-optical aberration and dithering are very important in studying aero-optical performance of supersonic mixing layer.

关键词： aero-optics supersonic mixing layer BOS

Status of study on biological and toxicological effects of nanoscale materials

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science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3 1. Laboratory for Bio-Environmental Health sciences of Nanoscale materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of sciences, beijing 100049, china 2. college of Chemistry and Molecular engineering, Peking university, beijing 100871, china 3. Department of Occupational and Environmental Health sciences, School of Public Health, Peking university, beijing 100083, china 1. Laboratory for Bio-Environmental Health sciences of Nanoscale materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. college of Chemistry and Molecular engineering Peking University 100871 Beijing China 3. Department of Occupational and Environmental Health sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Study on H atoms diffusion and adsorption properties of MgH_2-V systems

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science china(Technological sciences) 2008年第7期51卷 979-988页

作者： ZHOU DianWu1,2, LIU JinShui3 & PENG Ping3 1 State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan university, Changsha 410082, china 2 college of Mechanical and Automatic engineering, Hunan university, Changsha 410082, china 3 college of materials science and engineering, Hunan university, Changsha 410082, china 1. State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha 410082 China 2. college of Mechanical and Automatic engineering Hunan University Changsha 410082 China 3. college of materials science and engineering Hunan University Changsha 410082 China

Based on experimental results that VH0.81/MgH2 interface was found during the process of mechanically milling MgH2+5at.%V nanocomposite, H atoms diffusion and adsorption properties of MgH2-V systems have been investigated by using a first-principles plane-wave pseudopotential method based on the density functional theory. The results are as follows. When VH/MgH2 interface is formed due to V alloying MgH2 phase, the vacancy formed by H atoms near VH phase region is more stable than that without V alloying, while vacancy near MgH2 phase region is less stable than that without V alloying. During the process of H atoms diffusion after V alloying, the max migration barrier energy of H atoms in MgH2-V systems is reduced compared with that of MgH2 phase, which means that H atoms diffuse easily. When H diffuses into VH from MgH2 across VH/MgH2 interface, among three substitutions such as the replacement of H for V vacancy, or interstitial site or V atoms, the replacement of H for V vacancy has the strongest diffusion ability, next interstitial site, and finally V atoms site. As far as H adsorbed on different surfaces of VH phase is concerned, physical adsorption is carried out more easily than chemical adsorption, and the behavior of H atoms adsorbed on the surface near VH phase region can be found more easily than that near MgH2 phase region.

关键词： plane-wave pseudopotential theory magnesium hydride diffusion adsorption

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2:F film optically transparent electrode

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science china Chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2 & NIU Shuyan1,2 1. college of Chemistry and Molecular engineering, Qingdao university of science and technology, Qingdao 266042, china 2. college of Chemistry and chemical engineering, Ocean university of china, Qingdao 266003, china Correspondence should be addressed to Jiao Kui 1. college of Chemistry and Molecular engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of Chemistry and chemical engineering Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2:F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2, ZHANG Jiao qiang 3 (1. Department of Chemistry,Northwest university, Xi′an 710065, china 2. Department of Chemistry and chemical engineering, Baoji college of Arts and science, Baoji 721007, china 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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science china Earth sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2 & ZHOU Hui3 1. Laboratory of material in the Earth’s Interior, Institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, china 2. Department of Geology, china university of Geosciences, beijing 100083, china 3. Department of Geology, Peking university, beijing 100871, china 1. Laboratory of material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. Department of Geology China University of Geosciences 100083 Beijing China 3. Department of Geology Peking University 100871 Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12―200 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12 h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12―200 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12 h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

Preparation and properties of ultra-fine TiCN matrix cermets by vacuum microwave sintering

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Rare Metals 2010年第5期29卷 528-532页

作者： ZHANG Hou'an YAN Dike TANG Siwen Institute of material Preparation and Applied technology Xiamen University of Technology Xiamen 361024 China college of Electromechanical engineering Hunan University of Science and Technology Xiangtan 411201 China

Ultra-fine titanium carbonitride （TiCN） matrix materials with a grain size less than 1μm were successfully prepared by vacuum microwave sintering. The milling process for raw TiCN particles and the microstructure and properties of cermets produced with a composition of 15wt.%WC-17wt.%（Co＋Ni）-9wt.%Mo2C-59wt.%***0.3 and sintered by vacuum microwave were analyzed by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that a ball-to-powder mass ratio of 8：1 and a milling time of 50 h provided appropriate conditions for the production of ultra-fine TiCN solid solution powders. The use of vacuum microwave sintering produced cermets with much finer grain and black core structures and higher relative density and hardness than those produced by vacuum sintering technology.

关键词： cutting tools titanium carbonitride grain size microwave sintering milling hardness

Synthesis and Characterization of Poly (Aryl Ether Ketone) Containing Phthalazinone and Naphthalene Moieties

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Chinese chemical Letters 2000年第9期11卷 777-778页

作者： Ye GAO Xi Gao JIAN Jin Yan WANG Department of polymer science, college of chemical engineering, Dalian university of technology, Dalian 116012 Dalian Univ Technol Coll Chem Engn Dept Polymer Sci Dalian 116012 Peoples R China

A novel poly (aryl ether ketone) (PPEK) containing phthalazinone and naphthalene moieties was prepared by the nucleophilic displacement reaction of 4-(4-hydroxyphenyl) (2H) phthalazin-1-one with 1-chloro-4-(4-chlorobe... 详细信息

关键词： engineering thermoplastics poly (aryl ether ketone) synthesis