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Research on a New Type of Diamond Saw Plate

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厦门大学学报（自然科学版） 2002年第S1期41卷 294-295页

作者： SHI Xiao-liang, DUAN Long-chen, TANG Feng-lin, YANG Kai- hua (engineering faculty, china university of geosciences, {3. {4. Ch ina)

With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw plate. Layered segment for diamond saw plate is to divide single segment into s everal cutting tools by its structure, then increases rock-cutting faces. For i mpregnated man-made diamond saw plate, the bonding strength of diamonds with ma trix material has great effect on its life and service. Diamond is a kind of non metal and there is such high interface energy between diamond and common metals or alloys that diamond surface can’t be soaked by low melt-point metal or allo y. Diamonds are hold in metal matrix of working layer only mechanically, rather than bonded chemically, so the usage rate of diamonds in working layer is very l ow. Weakly impregnated method refers to covering diamonds with a thin layer of tu ngsten carbide mechanically by physical method, and chemical plating membrane re fers to coating a layer of carbide, which can react with the carbon atoms on the surface of diamond by chemical method and be soaked by matrix metal. In this pa per it analyses working mechanism and sintering process of layered segment of di amond saw plate by means of resistor hot-pressing sintering, it points out shor tages of layered structure, and raises using weakly impregnated layer instead of pure matrix layer, then overcomes the pure matrix layer slipping by pulling out diamonds earlier to improve cutting efficiency of saw plate, in the same time u ses diamond grains of chemical plating membrane proposed then preventing the hea t-hurting to diamond grains in working layer during the process of welding and sintering and improving the bonding strength of diamond with matrix, then improv ing life-span and aging of diamond saw. The theory of the design of mixed holding of diamonds by matrix of saw plate assures that chemical plating diamonds in working layer cut

关键词： diamond saw plate layered segment weakly impre gnated plating membrane slipping

Heterogeneous transition dynamic equations and the self-organized origin of the nesting rhythmic beddings in Panzhihua lithosomes

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science china Earth sciences 2005年第1期48卷 13-20页

作者： WU Jingping, LI Caiwei, BAO Zhengyu, YANG Wenhua, ZHOU Chenggang, SANG Zunan, LI Fanglin & QU Songsheng College of Chemistry and Molecular, wuhan university, wuhan 4.3}071, {3. faculty of Material science and chemical engineering, china university of geosciences, wuhan 4.0074. china Information Department, Zhongshan university, Guangzhou 510000, {3. faculty of Earth science, china university of geosciences, wuhan 4.0074. china College of Chemistry and Molecular Wuhan University Wuhan 430071 China faculty of Material science and chemical {3. China University of Geosciences Wuhan 430074 China Information Department Zhongshan UniversityGuangzhou 510000China faculty of Earth science China University of GeosciencesWuhan 430074China faculty of Material science and chemical {3. China University of GeosciencesWuhan 430074China College of Chemistry and Molecular Wuhan UniversityWuhan 430071China

Dynamic equations were developed for heterogeneous phase-transition in a system of coupled nucleation, growth and ripening. Based on these equations, a self-organized origin of small-scale nesting rhythmic beddings in Pahzhihua lithosomes was investigated and the results showed that the beddings could be formed by the cross supersaturated nucleation-crystallization of augite and feldspar successively. This process could be implemented by coupling with supersaturated nucleation, Ostwald ripening, component diffusion and the primary grain diffusion under a proper temperature gradient. The slightly intensive supersaturated nucleation and Ostwald ripening occurring in Panzhihua lithosomes may relate closely to the mineral components such as V-Ti-Maanetite.

关键词： heterogeneous transition, nesting rhythmic bedding, self-organized, Panzhihua.

Molecular and quantum mechanical studies on the monomer recognition of a highly-regular β-helical antifreeze protein

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science china Chemistry 2004年第1期47卷 34-40页

作者： YANG Zuoyin, JIA Zongchao, LIU Ruozhuang & CHEN GuangjuDepartment of Chemistry, Beijing Normal university, Beijing 100875, china faculty of {3., Beijing university of chemical Technology, Beijing 100029, china Department of Biochemistry, Queen’s university, Kingston, Ontario K7L 3.6, Canada 1. Department of Chemistry Beijing Normal University 100875 Beijing China 2. faculty of science Beijing University of Chemical Technology 100029 Beijing China 3. Department of Biochemistry Queen? University K7L 3N6 Kingston Ontario Canada

The possible interaction models for an antifreeze protein from Tenebrio molitar (TmAFP) have been systematically studied using the methods of molecular mechanics, molecular dynamics and quantum chemistry. It is hoped that these approaches would provide insights into the nature of interaction between protein monomers through sampling a number of interaction possibilities and evaluating their interaction energies between two monomers in the course of recognition. The results derived from the molecular mechanics indicate that monomer? β-sheets would be involved in interaction area and the side chains on two p-faces can match each other at the two-dimensional level. The results from molecular mechanics and ONIOM methods show that the strongest interaction energy could be gained through the formation of H-bonds when the twoβ-sheets are involved in the interaction model. Furthermore, the calculation of DFT and analysis of van der Waals bond charge density confirm further that recognition between the two TCTs mainly depends on inter-molecular hydroxyls. Therefore, our results demonstrate that during the course of interaction the most favorable association of TmAFPs is via their β-sheets.

关键词： antifreeze protein, recognition, dynamics simulation, molecular mechanics, quantum chemistry.

Analysis of trace mercury in water by solid phase extraction using dithizone modified nanometer titanium dioxide and cold vapor atomic absorption spectrometry

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Rare Metals 2007年第6期26卷 541-546页

作者： MA Xiaoguo HUANG Bei CHENG Meiqing faculty of Environmental science and engineering Guangdong University of Technology Guangzhou 510090 China Department of chemical engineering Maoming University Maoming 525000 China

A new method for analysis of trace mercury in water samples was developed, based on the combination of preconcentration/separation using dithizone-modified nanometer titanium dioxide （TiO2） as a solid phase extractant and determination by cold vapor atomic adsorption spectrometry （CVAAS）. Dithizone was dissolved with alcohol and loaded on the surface of nano-sized TiO2 powders by stirring. The static adsorption behavior of Hg^2＋on the dithizone-modified nanoparficles was investigated in detail. It was found that excellent adsorption ratio for Hg^2＋ could be obtained in the pH range of 7-8 with an oscillation time of 15 rain, and a 5 mL of 3.5 mol·L^-1 HCI solution could quantitatively elute Hg^2＋ from nanometer TiO2 powder. Common coexisting ions caused no obvious influence on the determination of mercury. The mechanisms for the adsorption and desorption were discussed. The detection limit （3.） for Hg^2＋ was calculated to be 5 ng·L^-1. The proposed method was applied to the determination of Hg^2＋ in a mineral water sample and a Zhujiang River water sample. By the standard addition method, the average recoveries were found to be 94.4.-108.3. with RSD （n = 5） of 2.9%-3.5%.

关键词： analytical chemistry mercury solid-phase extraction TiO2 nanoparticle cold vapor atomic adsorption spectrometry (CVAAS)

Devonian Frasnian-Famennian Transitional Milankovitch Cycles and High-Resolution Stratigraphic Correlation

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 354-363页

作者： GONG Yiming faculty of Earth science, china university of geosciences, {3., {4.I Baohua Laboratory of Marine Geology, Tongji university, Shanghai 200092and WU Yi Guangxi Institute of Geology, Nanning 53.023 faculty of Earth science China University of Geosciences Wuhan 430074 Laboratory of Marine Geology Tongji University Shanghai 200092 Guangxi Institute of Geology Nanning 530023 [?]4.ong Yiming Born in October 1958 graduated from the Department of Geology Wuhan College of Geology in 1981 received his Ph.D. degree in china university of geosciences in 1991. He is now a professor in the same university mainly engaged in high-resolution stratigraphy ichnology (trace fossils) and sedimentary geology. E- Mail: ymGONG@***

Four hierarchical cyclothems, superbundlesets, bundlesets, bundles and laminae, have been identified from the Devonian Frasnian-Famennian carbonate strata in Guangxi, South china. Their hierarchical structures, ratio relationships and sequence in conodont zones are continuous and stable and can be traced across different facies zones and sedimentary basins. Our data show that hierarchically organized superbundlesets, bundlesets, bundles and laminae correspond to the long eccentricity, eccentricity, obliquity or precession and sub-Milankovitch cycles respectively. Their periods were 4.0,000, 100,000, 3.,3.3. 16,667 and 8,000–17,000 a, respectively. The ratios of long eccentricity to eccentricity, eccentricity to obliquity, and eccentricity to precession in the Devonian are 1:4. 1:3.and 1:6 respectively. Using these hierarchical Milankovitch cyclothems, chronostratigraphical division and correlation can be realized at a resolution of 100 ka or 10 ka at the Frasnian-Famennian transition. The time intervals of the Upper rhenana Zone, linguiformis Zone, and the Lower, Middle and Upper triangularis Zone are 0.6, 0.8, 0.3. 0.3.and 0.3.Ma, respectively. Sea-level changes of the Frasnian-Famennian transition were not coherent and synchronous at the resolution of 100 ka or 10 ka in the basin-slope carbonate sequences of Guangxi, South china.

关键词： Milankovitch cycle high-resolution stratigraphic correlation sea-level change numerical dating Devonian Guangxi South china

Effect of strontium substitution on the activity of La_(2-x)Sr_xNiO_4.x=0.0-1.2)in NO decomposition

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science china Chemistry 2007年第1期50卷 41-46页

作者： ZHU JunJiang 1 ,YANG XiangGuang 2 ,XU XueLian 3.&WEI KeMei 1 1 National Research Center of chemical Fertilizer Catalysts,Fuzhou university,Fuzhou 3.0002,{4. 2 Changchun Institute of Applied Chemistry,Chinese Academy of {3.s,Changchun 13.022,{4. 3.ollege of Chemistry&chemical engineering,Fuzhou university,Fuzhou 3.0002,{4. 1. National Research Center of chemical Fertilizer Catalysts Fuzhou University Fuzhou 350002 China 2. Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China 3. College of Chemistry & chemical engineering Fuzhou University Fuzhou 350002 China

The aim of this work is to study the effect of Sr substitution on the redox properties and catalytic ac- tivity of La2-xSrxNiO4.x=0.0-1.2)for NO *** suggest that the x=0.6 sample shows the highest *** characterization(TPD,TPR,etc.)of samples indicates that the x=0.6 sample possesses suitable abilities in both oxidation and reduction,which facilitates the proceeding of oxygen desorption and NO *** temperature below 700℃,the oxygen desorption is difficult, and is the rate-determining step of NO *** the increase of reaction temperature(T> 700℃),the oxygen desorption is favorable and,the active adsorption of NO on the active site(NO+Vo+ Ni2+→NO^--Ni3.)turns out to be the rate-determining *** existence of oxygen vacancy is the prerequisite condition for NO decomposition,but its quantity does not relate much to the activity.

关键词： NO decomposition La2-xSrxNiO4 TPD TPR oxygen vacancy

Investigation on Vibrational Spectra and Structures of 4.Mercaptopyridine Monomer and Its Dihydrate

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chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2 , XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3.and GONG Bao-an 2 1. Key Laboratory for Supramolecular Structure and Material of Ministry of Education, Jilin university, Changchun 13.012, P. R. china 2. {4. and {3. College of Chemistry and Biology, Yantai university, Yantai 264.05, P. R. china 3. State Key Laboratory of Theoretical and Computational Chemistry, Jilin university, Changchun 13.023. P. R. china [a]Key Laboratory for Supramolecular Structure and Material of Ministry of Education Jiln University Changchun 130012 P. R. China[b]Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China[c]State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4.mercaptopyridine(4.PY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3.YP method with the 6-3.1++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4.PY and water molecules. Furthermore, the structure and the vibrational spectrum of 4.PY can be consi- derably affected by the water molecules.

关键词： 4.PY Dihydrate Vibrational spectra DFT Molecular structure

Tectonic Characteristics and Emplacement Mechanism of Dayishan Granite in Hunan Province, china

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Journal of Earth science 1999年第4期18卷 287-290页

作者： Li Xianfu(wuhan Institute of chemical Technology, wuhan 4.3}073.Li Jianwei Fu Zhaoren Li Zijin({3. of Earth sciences, china university of geosciences, wuhan 4.0074. wuhan Institute of chemical Technology Wuhan 430073 faculty of Earth sciences China University of GeosciencesWuhan 430074

Dayishan granite, a significant metallogenic-rock body located in Shaoyang-Chenxian tectonomagmatic belt of Hunan Province, was controlled by 'Dayishan-type' fault pattern. Based on the study of tectonic setting and geological features of the grantie, it is concluded that the tectonic system controlling magmatic emplacement is a shear folded-fauted zone which resulted from NW-trending convergent strike-slip faulting. The close relationship between the temporal-spatial distribution, emplacement mechanism of Dayishan granite and the strike-slip faulting is detailed.

关键词： strike-slip faulting tectonic style controlling granite emplacement mechanism,Dayishan Hunan Province

Controlled synthesis and magnetic properties of Fe_3._4.walnut spherical particles and octahedral microcrystals

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science china(Technological sciences) 2008年第11期51卷 1911-1920页

作者： JIAO Hua1,2 & YANG HeQing1 1 Key Laboratory of Macromolecular science of Shaanxi Province, School of Chemistry and Materials science, Shaanxi Normal university, Xi’an 710062, {3. 2 Department of Chemistry and {4. engineering, Weinan Teachers university, Wei nan 714.00, {3. Key Laboratory of Macromolecular science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an 710062 China Department of Chemistry and chemical engineering Weinan Teachers University Wei nan 714000 China

Magnetite Fe3.4.walnut spherical particles and octahedral microcrystals were suc- cessfully synthesized from K4.[Fe (CN) 6], K3.[Fe (CN) 6] and NaOH reagents via a simple hydrothermal process. And the uniform morphology of octahedral micro- crystals was obtained in the presence of ethylene glycol. The morphology and structure of products were characterized by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the Fe3.4.walnut spherical particles and octahedral microcrystals were single crystals with the face-center cubic structure and with size distributions from 2.2 to 8.6 μm and 1.6 to 12.5 μm, respectively. Their magnetic properties were detected by a vibrating sample magnetometer at room temperature. The walnut spherical parti- cles exhibited a ferromagnetic behavior with the coercive force (Hc), saturation magnetization (Ms) and remanent magnetization (Mr) being 150.57 Oe, 97.63. and 12.05 emu/g, respectively. For the octahedral microcrystals they were 75.28 Oe, 101.90 and 6.69 emu/g, respectively. Different sizes of walnut spherical particles were controlled synthesized through adjusting the NaOH concentration. It was found that ethylene glycol molecules have a significant effect on the formation of Fe3.4.octahedra. A possible mechanism was also proposed to account for the growth of these Fe3.4.products

关键词： a hydrothermal route Fe3.4 walnut spherical particles octahedral microcrystals magnetic property