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Science china chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of chemistry and Chemical {2.,Graduate {3. of Chinese Academy of Sciences,beijing 100049,china college of chemistry and Chemical {2. Graduate University of Chinese Academy of Sciences Beijing China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12.type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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Science china chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 college of Materials Science and {3., Shandong {2. of Technology, Zibo 2.5049, china 2.Department of chemistry, Jilin {2., Changchun 13.02., china college of Materials Science and engineering Shandong University of Technology Zibo China Department of chemistry Jilin University Changchun China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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Science china chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1,2. XIE Jie1, ZHAO Jingquan1 & ZHU Teng2.1. Key Laboratory of Photochemistry, Center for {3. Science, Institute of chemistry, The Chinese Academy of Sciences, beijing 100080, china 2. university of Science and Technology beijing, beijing 10083. china Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences Beijing China university of Science and Technology beijing Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>43. nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2.), trapped by DMPO, were detected. ?? It was proved that O2.was not originated from the singlet oxygen (1O2. but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2.were estimated to be 1.8, 1.1 and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.3., 0.53.and 0.14 respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

Progress in the study of molecular organized assemblies by dielectric relaxation spectroscopy

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Progress in Natural Science:Materials International 2006年第3期16卷 221-230页

作者： ZHAO Kongshuang, HE Kejuan and WEI Suxiang (Department of chemistry, beijing Normal {2., beijing 100875, china Department of chemistry, South china Normal {2., Guangzhou 51063., china) Department of chemistry Beijing Normal University Beijing 100875 China Department of chemistry South China Normal University Guangzhou 510631 China

Because dielectric spectroscopy covers a great many problems in physical and chemical systems occurring in an extremely wide frequency range, the study of this method plays an important role in physical chemistry. As an effective tool to detect inner properties of substance systems, the dielectric spectroscopy method is widely used in chemical systems and has been dramatically developed in recent decade. This review paper describes the applications of the dielectric spectroscopy in the chemical field, and main concentrations are focused on the micelle, microemulsion and other so-called molecular organized assemblies. Some dielectric principles and models proposed for these systems are introduced. In addition, recent technical developments in dielectric spectroscopy and developing trend of this method in other chemical systems are reviewed.

关键词： dielectric relaxation micelle microemulsion vesicle relaxation time.

Rh-Catalyzed Direct C-C Cleavage of Secondary Alcohols

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Rh-Catalyzed Direct C-C Cleavage of Secondary Alcohols

Development of rabbit monoclonal and polyclonal antibodies for detection of site-specific histone modifications and their application in analyzing overall modification levels

化学使世界更美好——中国化学会第七届有机化学学术会议

作者： Zhang-Jie Shi~* college of chemistry and molecular engineering,peking university,{2.,{3.

＜正＞Transition-metal catalyzed C—C bond cleavage has attracted much attention and emerged as a tremendous challenge during the past several ***,in order to facilitate C—C bond cleavage,two basic strategies are employed. One is to use strained three- or four-membered ring compounds,which undergo oxidative cyclometalation forming more

关键词： C—C bond cleavage Rh(Ⅲ)-catalyzedβ-carbon elimination

来源： cnki会议评论

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Cell Research 2006年第5期16卷 519-527页

作者： Lan Guo~(1,2.*) Benliang Yin~(1,*) Junli Zhou~(1,3. Xueyong Li~3.Xing Wang Deng~(1,2.3. ~1National Institute of Biological Science,Zhongguancun Life Science Park,beijing 102.06,china ~2.2.-Yale Joint Center of Plant molecular Genetics and Agrobiotechnology,college of Life Sciences,peking university,beijing 100871,china ~3.epartment of molecular,Cellular,and Developmental Biology,Yale {13.,New Haven,Connecticut 0652.-8104,USA National Institute of Biological Science Zhongguancun Life Science Park Beijing China peking-Yale Joint Center of Plant molecular Genetics and Agrobiotechnology College of Life Sciences Peking University Beijing China Department of molecular Cellular and Developmental Biology Yale University New Haven USA

In addition to DNA sequence information,site-specific histone modifications are another important determinant ofgene expression in a eukaryotic *** selected four modification sites in common histones that are known tosignificantly impact chromatin function and generated monoclonal or polyclonal antibodies that recognize each of thosesite-specific *** used these antibodies to demonstrate that the site-specific histone modification levelsremain relatively constant in different organs of the same *** also compared the levels of selected histonemodifications among several representative organisms and found that site-specific modifications are highly variable amongdifferent organisms,providing new insight into the evolutionary divergence of specific histone modifications.

关键词： histone modification site-specific antibody chromatin

Heterogeneous reaction of SO_2.on TiO_2.particles

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Science china chemistry 2010年第12期53卷 2637-2643页

作者： SHANG Jing,LI Jia & ZHU Tong State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering,{2.,{3.,china State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering Peking University Beijing China

The heterogeneous reaction of SO2.on TiO2.particles was studied using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS).The influences of the oxygen concentration,relative humidity (RH),and ultraviolet (UV) light illumination (λ=3.5 nm) intensity on the reaction were *** main product of the heterogeneous reaction of SO2.on TiO2.particles was sulfate with UV illumination and sulfite without *** production of sulfate was promoted significantly with UV illumination or water,and there was a synergistic effect when both were *** the dry system without UV,the heterogeneous reaction of SO2.on TiO2.particles was found to be second-order for SO2.and the initial uptake coefficient,BET,was determined to be 1.94 × *** UV and RH=40%,the reaction order was first-order and the initial uptake coefficient was 1.3. × 10-5.

关键词： SO2 TiO2 DRIFTS heterogeneous oxidation

Heterogeneous reactions of gaseous methanesulfonic acid with calcium carbonate and kaolinite particles

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Science china chemistry 2010年第12期53卷 2657-2662页

作者： TANG MingJin,LI MengQiu & ZHU Tong State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering,{2.,{3.,china State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering Peking University Beijing China

Heterogeneous reactions of gaseous methanesulfonic acid (MSA) with calcium carbonate (CaCO3. and kaolinite particles at room temperature were investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Methanesulfonate (MS-) was identified as the product in the condensed phase,in accordance with the product of the reaction of gaseous MSA with NaCl and sea salt *** the concentration of gaseous MSA was 1.3. × 10-13.molecules cm-3.the uptake coefficient was (1.2. ± 0.06) × 10-8 (1) for the reaction of gaseous MSA with CaCO3.and (4.10 ± 0.65) × 10 10 (1) for the reaction with *** uptake coefficients were significantly smaller than those of the reactions of gaseous MSA with NaCl and sea salt particles.

关键词： gaseous MSA heterogeneous reaction calcium carbonate kaolinite

Potential control of horseradish peroxidase immobilization on gold electrode

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中国科学：化学英文版 2004年第2期47卷 134-141页

作者： GE Cunwang1,2. YU Wei1, LI Changan1, WANG Nanping2.& GU Ning1 1. Key Laboratory of molecular and Biomolecular Electronics (Southeast {2.), Ministry of Education, Research Center for Nano-scale Science and Technology, Southeast {2., Nanjing 2.0096, china 2. Department of chemistry, Nantong Teachers college, Nantong 2.6007, china Key Laboratory of molecular and Biomolecular Electronics (Southeast {2.) Ministry of Education Research Center for Nano-scale Science and Technology Southeast University Nanjing China Department of chemistry Nantong Teachers College Nantong China

A new approach based on potential control was firstly used for the immobilization of horseradish peroxidase (HRP) as the model protein. The self-assembly monolayer (SAM) was prepared with 2.aminoethanethiol (AET) on the gold electrode. The charge on HRP was adjusted by means of the acidity of the phosphate buffer solution (PBS) for dissolving the HRP. The in-fluence of electric potential on HRP immobilization was investigated by means of colorimetric immunoassay of enzyme-substrate interaction (CIESI) using an automatic plate reader. The HRP modified electrodes were characterized with X-ray photoelectron spectroscopy (XPS) as well as atomic force microscope (AFM) on template-stripped gold surface. The potential for maximum immobilization of HRP was near the zero charge potential. The result indicates that controlled potential can affect the course of HRP immobilization without the loss of enzymic activity. It is of great significance for the control of biomolecular self-assembly and the intrinsic electric device.

关键词： electric potential control, horseradish peroxidase, immobilization, gold electrode, self-assembly.

Knockdown of CD146 reduces the migration and proliferation of human endothelial cells

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Cell Research 2006年第3期16卷 313-318页

作者： Yanyong Kang~(1,3. Fengcai Wang~(1,2. Jing Feng~1 Dongling Yang~1 Xu Yang~3.Xiyun Yan~11 National Laboratory of Biomacromolecules,Institute of Biophysics,Chinese Academy of Science beijing 100101,china 2.{2. Department,Anyang teacher's college,Anyang 455000,china 3.college of Life Science,Central china Normal university,Wuhan 43.079,china National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Science Beijing China college of Life Science Central China Normal University Wuhan China chemistry Department Anyang teacher's College Anyang China

Our previous study has demonstrated that CD 146 molecule is a biomarker on vascular endothelium,which is involvedin angiogenesis and tumor *** the mechanism behind is not *** we have for the first time devel-oped a novel CD146 blockade system using CD146 siRNA to study its function on endothelial *** data showedthat CD146 siRNA specifically blocked the expression of CD146 on both mRNA and protein levels,leading to thesignificant suppression of HUVEC proliferation,adhesion and *** results demonstrate that CD146 playsa key role in vascular endothelial cell activity and angiogenesis,and CD146 siRNA can be used as a new inhibitor foranti-angiogenesis therapy.

关键词： small interfering RNA adhesion molecule CD 146 vascular endothelial cell