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Journal of Wuhan university of Technology(Materials Science) 2009年第2期24卷 245-248页

作者：胡卫兵 school of chemical and Environmental {2. Hubei Institute for Nationalities Department of Physics Huazhong University of Science and Technology

Novel Nb2.5 nanorods and polygonal Nb2.5 platelets were generated by a simple solvothermal technique. The geometry evolution of the resultant Nb2.5 from amorphous nanoparticles to crystallized particles, from polygonal platelets to well-elongated nanorods was been studied in detail. The processing parameters, including the reaction temperature, reaction time, concentration of the precursors, and pH value of the solution, which affect the shape and size of the nanorods, were investigated. The Nb2.5 nanorods with different aspect ratios were examined by XRD, SEM and TEM. The experimental results show that Nb2.5 nanorod is the orthorhombic structure and well-crystallized. The growth of the nanorods follows their [001] direction. The successful generation of high quality Nb2.5 nanorods is not only important for transition metal oxide research, but also potentially important for further formation of new Nb-based 1-D nanostructures, such as NbS2.and NbN.

关键词： solvothermal morphological evolution Nb2.5 nanomateraials

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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Science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2. CUI Yuezhi3, HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong university, Jinan 2.0100, china 2. {2. of Information Science and engineering, Shandong university, Jinan 2.0100, china 3. Department of chemical engineering, Light Industry College of Shandong, Jinan 2.0100, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of Science and Technology, Wuhan 430074, china 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. school of Information Science and engineering Shandong University 250100 Jinan China 3. Department of chemical engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2.4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2.4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2.methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2.. NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2.order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2.molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P2. space group. Its powder crystals exhibit a 2.order harmonic intensity 46.2.times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2.order nonlinear optical (NLO) efficiency on the micro 2.order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

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 {2., Beijing 100871, china 3. Department of Occupational and Environmental Health Sciences, school of Public Health, Peking {2., 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.

Reverse extraction of early-age hydration kinetic equation from observed data of Portland cement

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Science china(Technological Sciences) 2010年第6期53卷 1540-1553页

作者： WANG Lin1,YANG Bo2.ZHAO XiuYang1,2.CHEN YueHui2.& CHANG Jun3 1 school of Computer Science and Technology,Shandong university,Jinan 2.0101,{2. 2.Provincial Key Laboratory for Network-based Intelligent Computing,university of Jinan,Jinan 2.002.,{2. 3 school of Material Science and engineering,university of Jinan,Jinan 2.002.,{2. 1. school of Computer Science and Technology Shandong University Jinan 250101 China2. Provincial Key Laboratory for Network-based Intelligent Computing University of Jinan Jinan 250022 China3. School of Material Science and Engineering University of Jinan Jinan 250022 China

The early-age hydration of Portland cement paste has an important impact on the formation of microstructure and development of ***,manual derivation of hydration kinetic equation is very difficult because there are multi-phased,multi-sized and interrelated complex chemical and physical reactions during cement *** this paper,early-age hydration kinetic equation is reversely extracted automatically from the observed time series of hydration degree of Portland cement using evolutionary computation method that combines gene expression programming and particle swarm optimization *** order to reduce the computing time,GPUs are used for acceleration in *** have shown that according to the extracted kinetic equation,simulation curve of early-age hydration is in good accordance with the observed experimental ***,this equation still has a good generalization ability even changing chemical composition,particle size and curing conditions.

关键词： Portland cement hydration kinetic equation reverse extraction gene expression programming particle swarm optimization

Wavelet fractal character of overlapping signal

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Chinese Science Bulletin 2003年第1期48卷 44-49页

作者： QIU Jianding1,2. ZOU Xiaoyong1, LIANG Ruping1,2. MO Jinyuan1 & CAI Peixiang1 1. school of Chemistry and chemical {2., Zhongshan Univer-sity, Guangzhou 5102.5, china 2. Department of chemical {2., Pingxiang College, Pingxiang 337055, china Correspondence should be addressed to Mo Jinyuan (e-mail: cesmjy @***) school of Chemistry and chemical {2. Zhongshan University Guangzhou 510275 China Department of chemical engineering Pingxiang College Pingxiang 337055 China

A new method based on the combining of the wavelet theory with the fractal theory and named wavelet fractal peak position method (WFPPM) is introduced to ex-tract the number of the components and the relevant peak positions from overlapping signals in chemistry. The over-lapping signal is first transformed into continuous wavelet transform value of time domain in certain dilation range via continuous wavelet transform (CWT), and then changed into capacity dimensions (Dc). The number of the components and the relevant positions of overlapping peaks can be iden-tified easily according to the change of Dc. An investigation concerning the influence of different dilation ranges on the peak positions extracted by WFPPM is also provided. Stud-ies show that the WFPPM is an efficient tool for extracting the peak positions and identifying the number of peaks from unresolved signals, even when this kind of overlapping is significantly serious. Relative errors of less than 1.0% in peak positions are found when WFPPM is used in the pro- cessing of the cadmium(Ⅱ)-indium(Ⅲ) mixture system. The analytical results demonstrate that the desired peak positions can be extracted conveniently, accurately and rapidly from an unresolved signal via WFPPM. Tremendous developing and applications based on currently reported WFPPM in extracting overlapping signals would be expected in the near future.

关键词：重叠信号化学信号电分析化学分离度小波伸缩尖峰位置

The Growth of Latex Particles during the VAc/BA Copolymerization

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Journal of Wuhan university of Technology(Materials Science) 2006年第3期21卷 86-89页

作者：秦少雄 school of chemical and Energy {2. South China University of TechnologyGuangzhou 510640 ChinaCollege of Chemistry and Environment Engineering Yangtze UniversityJingzhou 434100China

The semi-continuous seeded emulsion eopolymerization of vinyl acetate and butyl acrylate was carried out with hydroxyethyl cellulose as a colloid stabilizer. The morphology of the latex particle and the relationship between the reaction time and the average particle diameter and/or the conversion ratio during the polymerization were invstiguted. The experimental results shaw that the morphology of the latex particle possesses the stable sterie construction. In the seeded polymerizution, the average particle diameter of latex decreased while the conversion ratio increased. At the second term of the emulsion copolymerization （the growth stage of particle size）, the latex particle average diameter increased with copolymerization continuously, but the instantaneous conversation ratio was not large, so it was very necessaO to properly prolong the time during the holding temperature stage.

关键词： hydroxyethyl cellulose VAc/ BA latex average particle diameter conversion ratio

Preparation and Magnetic Properties of Mn-Zn Ferrites by the Co-precipitation Method

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Journal of Wuhan university of Technology(Materials Science) 2009年第6期24卷 875-878页

作者：李雪张俊喜 school of Environmental and chemical {2. Shanghai University Electrochemical Research Group Shanghai University of Electric PowerKey Laboratory of State Power Corporation of China

Mn-Zn ferrites （Mn1-xZnxFe2.4） with different compositions were prepared by the coprecipitation method, and the influences of such synthesis conditions as pH value, composition and volume ratio （R） of the mixed solution and NH4HCO3 solution on their microstructures and magnetic properties were discussed. The samples were characterized by X-ray diffraction （XRD） and magnetization measurement instrument. Lattice parameters and average crystalline size of the synthesized materials were calculated from the corresponding XRD patterns with the related software Jade.5. For samples of different pH values, only one phase was found when pH values were 7.0, 8.0 and 9.0. The sample with pH value of 7.0 exhibited the highest saturation magnetic induction, the lowest coercive force, and crystallized best. For samples of different R values with pH value of 7.0, only one phase was observed in all samples, and the sample with R value of 2.3 exhibited the highest saturation magnetic induction and the lowest coercive force. The composition has mainly afected the magnetic properties, and the saturation magnetic induction increases with the increase of the content of Zn （x）, but decreases when x is beyond 0.6. The trend of coercive force is on the contrary. However, no magnetism is exhibited when the x value is up to 0.8.

关键词： co-precipitation method microstructure magnetic property Mn-Zn ferrite

Integration of chemical product development, process design and operation based on a kilo-plant

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Progress in Natural Science:Materials International 2006年第6期16卷 600-606页

作者： QIAN Yu, WU Zhihui and JIANG Yanbin (school of chemical {2., South china university of Technology, Guangzhou 510640, china) [a] school of chemical {2. South China University of Technology Guangzhou China

Presented in this paper is an integrated approach of computer-aided product development, process design and operation analysis based on a kilo-plant. The implemented kilo-plant, as a research platform to manufacture product in kilogram-scale, was designed especially for fine and specialty chemicals. The characteristics of product synthesis, process operation and product quality control are investigated coupled with computer-aided monitoring, online modeling, simulation and operation process optimization. In this way, chemical product discovery, process design and operation are integrated in a systematic approach, in the aim to respond to rapid changing marketplace demands to new products.

关键词： integration kilo-plant product development process operation process analysis.

Change of asphaltene and resin properties after catalytic aquathermolysis

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Petroleum Science 2009年第2期6卷 194-200页

作者： Yi Yufeng Li Shuyuan Ding Fuchen Yu Hang school of chemical Science and {2. China University of Petroleum （Beijing） Beijing 102249 China school of chemical {2. Beijing Institute of Petrol-chemical Technology Beijing 102617 China

Resin and asphaltene were separated from Liaohe heavy oil. Catalytic aquathermolysis of asphaltene and resin was investigated by using water soluble catalysts （NiSO4 and FeSO4） and oil soluble catalysts （nickel naphthenate and iron naphthenate）. Before and after aquathermolysis, the properties of the resin and asphaltene was compared by means of ultimate analysis, vapor pressure osmometer （VPO） average molecular weight, X-ray diffraction （XRD）,^13C and ^1H nuclear magnetic resonance （NMR）. The conversion sequence was as follows： No-catalyst〈NiSO4〈FeSO4〈nickel naphthenate〈iron naphthenate. In the presence of catalysts, the amount of H2.and CO increased significantly, while H2. in the gas product decreased. The molecular weight of asphaltene and resin increased after reaction without catalyst. But the catalysts restrained this trend. The H/C ratio of asphaltene and resin decreased after reaction. From the results of average structural parameters and molecular weight, it was found that asphaltene and resin were partly aggregated after aquathermolysis.

关键词： Asphaltene resin aquathermolysis molecular weight catalyst

Effect of chemical Composition on Oxide Transformation and MnS Precipitation Upon Oxide Particles in Fe-Cr Alloy by Heat Treatment

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Journal of Iron and Steel Research International 2011年第S2期18卷 377-382页

作者： WANG Mao1, WANG Xin-hua1, YU Hui-xiang1, KITAMURA Shinya2. SHIBATA Hiroyuki2.(1. school of Metallurgical and Ecological engineering, {2. of Science and Technology Beijing, Beijing 100083, china 2. Institute of Multidisciplinary Research for Advanced Materials, Tohoku {2., Sendai, Miyagi 980-8577, Japan) Univ Sci & Technol Beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China Tohoku Univ Inst Multidisciplinary Res Adv Mat Sendai Miyagi 9808577 Japan

The transformation of nonmetallic inclusions and the change of MnS precipitation ratio on oxide particles during heat treatment were studied by using Fe-10%Cr alloy containing different Si and S content in the present study. The phenomenon of oxide transformation in alloy in this research was characterized according to Si content. When the Si content was lower, the typical inclusions changed from MnO?SiO2.type to MnO?Cr2.3 type by heat treatment. In the case of high S concentration, the obvious MnS area in inclusions was observed after heat treatment. It was more favorable for MnS precipitation as the S content was improved from approximately 2.×10-6 to 60×10-6. The MnS precipitation ratio on oxide particles was higher on MnO?SiO2.type than MnO-Cr2.3 type oxide particles. Besides, the ratio on the two kinds of oxides increased with increasing the time for heat treatment at 1473K as a whole. The theoretical Mn content at which MnS can precipitate agrees well with the experimental results.

关键词： nonmetallic inclusion oxide transformation Manganese Sulphide precipitation ratio heat treatment