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Metal Ion Complexation of Bilirubin Monolayer

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Chinese Chemical Letters 1999年第6期10卷 507-510页

作者： Jian-Ming OUYANG Chuan LI Wei Han LING Wen Jie ZHENG (Department of Chemistry. jinan University. guangzhou {2.) jinan Univ Dept Chem Guangzhou 510632 Peoples R China

The surface pressure-area isotherms of bilirubin (BR) monolayers at an air-water interface on subphases with and without metal ions were investigated. The formation of BR-metal complexes leads to changes in the shape of isotherms of BR and changes in UV-visible absorption spectra of the monolayer assemblies. In XPS spectra new XPS peaks assigned to the metal ions containing subphases appeared. Low-angle X-ray diffraction indicates this Y-type LB films of MBR were formed with bilayer spacing of ca. 2.1 nm.

关键词： monolayer bilirubin complexation

Preparation of CaS:Eu^(2.) Phosphor by Microwave Heating Method and its Luminescence

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Chinese Chemical Letters 2000年第9期11卷 843-846页

作者： Peng Jun LIU Ying Liang LIU Department of Chemistry, jinan University, guangzhou {2. Department of Chemistry, Hainan Normal College, Haikou 571158 jinan Univ Dept Chem Guangzhou 510632 Peoples R China Hainan Normal Coll Dept Chem Haikou 571158 Peoples R China

This is the first report of using the microwave heating technique to synthesize calcium sulphide activated by europium whose structure is determined as the face-centered cubic by conventional X-ray powder diffraction method. The phosphor has maximum excitation peaks located at 2.0 urn and 560 urn and the maximum emission of the phosphor is 630 nm. When the concentration of Eu^(2.) in CaS increases from I .0 × 10^(-5) to l.0 × 10^(-2. mole per mole host, the body colour of the calcium sulphide activated with europium changes from white, through light-red to pink to deep-red. The phosphor obtains the longest afterglow at the concentration of 0.1% Eu^(2.)doped and is a kind of good material excited by sunlight.

关键词： Microwave radiation heating calcium sulphide europium luminescence.

Effect of ball milling process on the microstructure of titanium-nanohydroxyapatite composite powder

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Rare Metals 2007年第2期26卷 118-123页

作者： PANG Pengsha LI Wei LIU Ying Department of Materials Science and Engineering Jinan University Guangzhou 510632 China GRIPM Advanced Materials Co. Ltd General Research Institute for Nonferrous Metals Beijing 100088 China

Titaninm-nanohydroxyapatite （Ti-nHA） composite powders, composed of titanium with 10 vol.% and 2. vol.% of nano-hydroxyapatite, were milled in a planetary ball mill using alcohol media to avoid excessive heat. XRD and SEM were performed for characterization of the microstructure, and the homogeneity of Ti/HA nanocomposite powder was evaluated by EPMA with prolonged ball milling time. The results show that under the condition of wet milling, the grain size of Ti-nHA composite powders is decreased with the increase in ball milling time and the amount of the addition of nHA. While for milling of 30 h, the nanocomposite powder with free structure, which consists of the nano-hydroxyapatite （nHA） particles and titanium （Ti） phase, is obtained. Three stages of milling can be observed from the dement mapping of Ti, Ca, and P by EPMA; meanwhile, it is found that the nHA would be more homogenously distributed after milling for 30 h.

关键词： composite materials nanocomposites mechanical milling titanium nanohydroxyapatite

Climatic fluctuation and disasters during recent 100 years in china’s tropics

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Journal of Geographical Sciences 2004年第S1期 14-22页

作者： HUANG Zhenguo1, ZHANG Weiqiang2.1. guangzhou Institute of Geography, guangzhou 510070, {2. 2. Guangdong Business College, guangzhou 51032., {2.)

The temperature appeared rising trend during the 2.th century in china's tropics. Two cooling stages and two warming stages in the process of climatic fluctuation can be recognized. After the 1980s the climate is the warmest which corresponds to the global change, but the warmest period is the 1940s in Kunming. The climate pattern mostly appears contemporaneity of warming and humidity, which is different from the situation of whole china. The natural disasters tend to be aggravated. The number of typhoons increased. Flood damages occurred frequently in the years of more typhoons. The number of droughts and cold damages increased. It was snowed in {2.. There was frost in Haikou and Yaxian. Four years of heavy snow have been recorded in Kunming.

关键词： natural disaster climatic fluctuation china’s tropics

Evaluation of Circulating Antisperm Antibody in Infertile Women with Polycystic Ovary Syndrome

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Journal of Reproduction and Contraception 2012年第1期23卷 25-28页

作者： Xiao-yi YANG Wei-jie ZHU Jing LI Department of Obstetrics and Gynecology the First People's Hospital of FoshanFoshan 52800China Institute of Reproductive Immunology Jinan UniversityGuangzhou 510632China Department of Pathophysiology Medical CollegeJinan UniversityGuangzhou 510632China

Objective To evaluate levels of the circulating antisperm antibody （ASA） in infertile women with polycystic ovary syndrome （PCOS）.Methods Forty-six infertile women with PCOS were enrolled into this study. The serum was screened by the indirect immunobead test for ASA type IgG and IgA according to the WHO laboratory *** Of the 46 patients assessed for ASA-IgG, 3 cases had immunobead binding which were 2.%, 2.% and 35%, respectively, and the sub-positive rate was 6.5%. No case had the clinical positive level according to the WHO criteria （50% or more of the motile sperm with immunobead binding）. ASA-IgA was not detected in all cases. Conclusion The circulating ASA is not associated with the pathogenesis of infertile women with PCOS.

关键词： antisperm antibody (ASA) polycystic ovary syndrome (PCOS) woman

Formation and Evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 26-32页

作者： Han Mei 1, Zhou Baohua 2. Yang Peilin 1,Gao Guiqin 1 & Zhang Weiying 1 1. Department of Geography, Shandong Normal University, jinan 2.0014, china 2. Department of Geography, jinan University, jinan 2.0001, china Department of Geography Shandong Normal University Jinan 250014 China Department of Geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

Dimension and measure theoretic entropy of a subshift in symbolic space

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Chinese Science Bulletin 1997年第14期42卷 1193-1196页

作者： CHEN Ercai and XIONG Jincheng1. Department of Astronomy, Nanjing University, Nangjing 2.0093, china 2. Department of Mathematics, South china Normal University, {2. 510631, china Department of Astronomy Nanjing University Nangjing China Department of Mathematics South China Normal University Guangzhou China

1 Definitions and resultsWITH the development of the theory of dynamical systems and fractal geometry, one provedthat symbolic dynamics is a powerful tool to study chaos and fractals. It is useful to study thefractal characteristics of symbolic dynamics. In the present note we shall point out the relationbetween the dimension and measure theoretic entropy of any subshift in symbolic space. Weprove here that the Bowen’s formula for Hausdorff dimension holds without Markov struc-ture. A variational principle for dimension is obtained.

关键词： symbolic space subshift measure theoretic entropy dimension.

Ground state and polaron and bipolaron excited states in polydiacetylene

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 430-439页

作者： LI Yuan1, HU Guichao1, XIA Caijuan1, LIU Desheng1,2.& XIE Shijie1,2.1. School of Physics and Microelectronics, Shandong University, jinan 2.0100, china 2. National Key Laboratory of Crystal Materials, Shandong University, jinan 2.0100, china 1. School of Physics and Microelectronics Shandong University Jinan 250100 China 2. National Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

The electronic properties of ground state and charged excited states of nondegenerate polydiacetylene were investigated by means of a tight-binding model. The parameters of the model were obtained by comparison of the experimental and other theoretical results. It was found that there is a stable dimerized structure of polydiacetylene in ground state and the doping induces the nonlinear excitations, such as polarons and bipolarons. In order to compare the stability of polaron and bipolaron, the creation energy and binding energy were separately defined. By neglecting the electron-electron Coulomb interaction, a bipolaron is more stable than two independent polarons.

关键词： dimerization, polaron, bipolaron, binding energy.

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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Chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1, ZHAO Zhenhua 1, SHI Manquan 1, YANG Shufeng 2.and CHEN Hanlin 2.1. guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640, {2. 2. Department of Earth Sciences, Zhejiang University, Hangzhou 31002., {2. guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of Earth Sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South china. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at 2.1 MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.