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Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science china chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2, HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. college of chemistry and Environment Science, Hebei university, Baoding 071002, china 2. International Center for Materials Physics, chinese academy of sciences, Shenyang 110016, china 3. college of Physics Science and Technology, Hebei university, Baoding 071002, china college of chemistry and Environment Science Hebei University Baoding China International Center for Materials Physics Chinese Academy of Sciences Shenyang China college of Physics Science and Technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

SYNTHESIS AND CHARACTERIZATION OF A NOVEL BLUE LIGHT EMITTING ROD-COIL DIBLOCK OLIGOMER

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chinese Journal of Polymer Science 2002年第5期20卷 401-407页

作者： Lifang Yang Haifeng He Hongqing Cao Xinhua Wan Qi-feng Zhou Department of Polymer Science & engineering college of chemistry & Molecular engineering Peking university beijing 100871, china Department of Polymer Science & engineering College of Chemistry & Molecular Engineering Peking University 北京 100871 Department of Polymer Science & engineering College of Chemistry & Molecular Engineering Peking University 北京 100871

Four new rod-coil diblock molecules, which had well-defined para-phenylene oligomers (PPP, from biphenyl to quinquephenyl) as rigid segments and poly(ethylene oxide) (PEO, M-w ca. 750) as flexible segments, were synthesized. The chemical structure and the number of repeating unit in PEO coil and PPP rod were characterized by H-1-NMR and MALDI-TOF mass spectrometry. The diblock oligomers showed good solubility in common organic solvents and aggregated in water as characterized by a blue shift in UV-vis absorption spectra, a red shift in emission spectra, quenching of the fluorescence and formation of the microfibrilla and fractal-like structures. The formation of different supramolecular structures meant that this effort might lead to commercial important highly organized functional materials.

关键词： rod-coil diblock oligomer MALDI-TOF mass spectrometry microfibrilla aggregate fractal-like pattern

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science china chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3, ZHAO Ying2, LING Xiaofeng3, LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3, ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, college of chemistry and Molecular engineering, Peking university, beijing 100871, china 2. Institute of chemistry, chinese academy of sciences, beijing 100080, china 3. Department of Surgery, Third Hospital, Peking university, beijing 100083, china 4. Department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University Beijing China Department of Surgery Third Hospital Peking University Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China Department of Oncology Surgery the First Hospital of Xi’an Jiaotong University Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 32 normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

Preparation of Polymeric Monolithic Column and Application to the Resolution of Aromatic Compounds in Capillary Electrochromatography

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chinese chemical Letters 2004年第12期15卷 1477-1479页

作者： Xia WANG Wen Zhi LI Chun Hui LIU Yong Min LI Li Ren CHEN Lanzhou Institute of chemical Physics chinese academy of sciences, LanZhou 730000 college of chemistry and chemical Engeering,Liaocheng university, Liaochang 252059 Lanzhou Inst. of chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Coll. of Chem. and Chem. Engeering Liaocheng University Liaocheng 252059 China

Polymeric monolithic capillary column-poly(GMA-co-EDMA-co-AMPS) was prepared andused for resolution of aromatic compounds (benzalcohol, 2-phenylethanol, toluene, ethylbenzene).

关键词： Polymeric monolithic column aromatic compounds c apillary electrochromatography.

Approach to synthesis of novel chiral 3-chloro-2(5H)- furanone and its application in asymmetric reactions

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chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. Department of chemistry, Tonghua Teacher’s college, Tonghua 134002, china 2. Department of chemistry, beijing Normal university, beijing 100875, china Department of chemistry Tonghua Teacher’s College Tonghua China Department of chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2-(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

A Convenient Method for the Stereoselective Synthesis of 7αHydroxycholesterol

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chinese chemical Letters 1998年第8期9卷 715-716页

作者： Ling Jie GAO and Tian Zeng ZHAO Guang Dian HAN(The Institute of chemistry, Henan academy of sciences, Zhengzhou, 450002)(Institute of Materia Medica, Peking Union Medical college,chinese academy of Medical sciences, beijing 100050) Institute of chemistry Henan Academy of Sciences Zhengzhou 450002 China Institute of Materia Medica Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100050 China

7α-Hydroxycholesterol was prepared from cholesteryl acetate via allylic browhnation followed by hydroxylation in 73% overall yield.

关键词： 7α-hyrdoxycholesterol cholesteryl acetate stereoselective hydroxylation

Ethylene oligomerization by novel iron(Ⅱ) diimine complexes/MAO

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chinese Science Bulletin 2002年第19期47卷 1616-1618页

作者： WANG Hang, YAN Weidong, JIANG Tao, LIU Binbin, XU Wenqing, MA Jianjiang & HU YouliangState Key Laboratory of engineering Plastics, Center for Molecular Science, Institute of chemistry, chinese academy of sciences, beijing 100080, china graduate Student of State Key Lab. of Eng. Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Grad. Student chinese Acad. of Sci. Beijing 100039 China Inst. of Polymer Science/engineering School of Chemical Engineering Hebei University of Technology Tianjin 300130 China Dept. of Petrochemical engineering Daqing Petroleum Institute Anda 151400 China Res. Inst. Dushanzi Petrochem. Co. PetroChina Xinjiang 833600 China

Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.

关键词： late-transition-metal catalysts ethylene oligomerization α-olefin.

Synthesis, Crystal Structures and Catalysis of Dinuclear Cd(Ⅱ) Complexes Bridged by Unusual (N,O,O′)-Coordinated α-Amino Acids

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chemical Research in chinese Universities 2012年第1期28卷 73-78页

作者： DENG Dong-sheng1,2, WANG Li1, PEI Ya-mei1, FENG Lu2 and LIU Chang-lin1 1. Key Laboratory of Pesticide & chemical Biology, Ministry of Education, School of chemistry, Central china Normal university, Wuhan 430079, P. R. china 2. college of chemistry and chemical engineering, Luoyang Normal university, Luoyang 471022, P. R. china School of chemistry Central China Normal University Key Laboratory of Pesticide & Chemical Biology Ministry of Education Wuhan 430079 college of chemistry and chemical engineering Luoyang Normal University Luoyang 471022

Four dinuclear amino acid cadmium（II） complexes [Cd2（tren）2（dl-alaninato）]（ClO4）3·H2O（I）, [Cd2（tren）2· （l-alaninato）]（ClO4）3·H2O（II）, [Cd2（tren）2（dl-phenylalaninato）]（ClO4）3（III） and [Cd2（tren）2（l-phenylalaninato）]· （ClO4）3（IV）, constructed from mixed ligands of tris（2-aminoethyl）amine（tren） and racemic or natural amino ac ids（amino acids=dl or l-alanine, and dl or l-phenylalanine）, have been synthesized and characterized by X-ray crys tallography. The structural analysis of complexes I and III reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual （N,O,O′）-bridged mode, resulting in asymmetric chromo phores of CdN4O and CdN5O in complex I, CdN4O2 and CdN5O in complex III, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the dias tereoselectivity of the reaction favors the formation of the syn-isomers.

关键词： Dinuclear cadmium(II) complex Amino acid Aldol reaction

Assessment of candidate plant DNA barcodes using the Rutaceae family

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Science china(Life sciences) 2010年第6期53卷 701-708页

作者： LUO Kun1,2,CHEN ShiLin1,CHEN KeLi2,SONG JingYuan1,YAO Hui1,MA XinYe1,ZHU YingJie3,PANG XiaoHui1,YU Hua1,LI XiWen1,4 & LIU Zhen2 1Institute of Medicinal Plant Development,Peking Union Medical college,chinese academy of Medical sciences,beijing 100193,china 2college of Pharmacy,Hubei university of chinese Medicine,Wuhan 430061,china 3School of Bioscience and engineering,Southwest Jiaotong university,Chengdu 610031,china 4Department of chemistry,Tsinghua university,beijing 100084,china Institute of Medicinal Plant Development Peking Union Medical College Chinese Academy of Medical Sciences Beijing China college of Pharmacy Hubei University of Chinese Medicine Wuhan China School of Bioscience and engineering Southwest Jiaotong University Chengdu China Department of chemistry Tsinghua University Beijing China

DNA barcoding is a rapidly developing frontier technology that is gaining worldwide ***,seven regions (psbA-trnH,matK,ycf5,rpoC1,rbcL,ITS2,and ITS) with potential for use as DNA barcodes were tested for their ability to identify 300 samples of 192 species from 72 genera of the family *** evaluate each barcode’s utility for species authentication,PCR amplification efficiency,genetic divergence,and barcoding gaps were *** found that the ITS2 region exhibited the highest inter-specific divergence,and that this was significantly higher than the intra-specific variation in the "DNA barcoding gap" assessment and Wilcoxon two-sample *** ITS2 locus had the highest identification efficiency among all tested *** a previous study,we found that ITS2 was able to discriminate a wide range of plant taxa,and here we confirmed that ITS2 was also able to discriminate a number of closely related ***,we propose that ITS2 is a promising candidate barcode for plant species identification.

关键词： DNA barcoding ITS2 Rutaceae identification