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Science china Chemistry 2005年第Z1期48卷 45-49页

作者： SU Biyun,ZHAO Jianshe & SUN Wenhua Department of Chemistry,Northwest university,Xi’an 710069,china State Key Laboratory of Engineering Plastics and {2. for molecular Science,Institute of Chemistry,Chinese Academy of Sciences,beijing 100080,china Department of Chemistry Northwest University Xi’an China State Key Laboratory of Engineering Plastics and center for molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing China

A series of new complexes {2.6-bis[1-((2.methyl-4-methoxyphenyl)imino)ethyl]pyri-dine}MCI2.[M=Fe(Ⅱ) (2., Co(Ⅱ) (3), Ni(Ⅱ) (4), Cu(Ⅱ) (5), Zn(Ⅱ) (6)] have been synthesized. At 2.℃, using 500 equiv of methylaluminoxane (MAO), the activities of Fe(Ⅱ), Co(Ⅱ) catalysts can reach 4.02.106 g/mol-Fehatm for ethylene polymerization and 3.98×105 g/mol-Cohatm for ethylene oligomerization. The effects of polymerization conditions such as reaction temperature, Al/M molar ratio and time on the activity of catalyst have been explored.

关键词： Bis(imino)pyridine transition metal complex, ethylene polymerization/oligomerization, catalytic activity.

IR STUDY ON MONOmolecular PARTICLE AGGLOMERATES OF POLYSTYRENE OBTAINED BY FREEZE-DRYING OF ITS DILUTE SOLUTION

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Chinese Journal of Polymer Science 2002年第4期20卷 381-383页

作者： Song Wang Qing-hua Wang Rong-shi Cheng Research center of Materials beijing Institute of Technology beijing 100081, china Department of Chemistry Nanjing university Nanjing 2.0093, china Research center of Materials Beijing Institute of Technology 北京 100081 Department of Chemistry Nanjing University Nanjing 210093

The monomolecular particle agglomerates of polystyrenes were obtained by freeze-drying of its very dilute solutions of 1.3 x 10(-5)-2.0 x 10(-5) g/mL in benzene:cylcohexane (100:1) solvents, and they were annealed at room temperature for hundred days before use. According to C-13-NMR measurement the polystyrenes should be practically atactic. The number average molecular weights of the samples are 2.80 x 10(3), 2.00 x 10(4), and 1.55 x 10(6), respectively. The freeze-dried aPS with a molecular weight higher than 10(4) show two new IR absorption bands at 1098 and 12.1 cm(-1), which are absent in the normal aPS and freeze-dried styrene oligomer. It was also found that the low molecular weight samples can only form powders, whereas the freeze-dried aPS with higher molecular weight form a mixture of powders and fibrils, of which the longer fibrils show a much stronger 12.1 cm(-1) band than the shorter fibrils and the powder. It seems that the 12.1 cm(-1) band corresponds to the stacking behavior of monomolecular particles.

关键词： monomolecular particles atactic polystyrene FTIR spectroscopy

The intracellular mechanism of alpha-fetoprotein promoting the proliferation of NIH 3T3 cells

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Cell Research 2002年第2期12卷 151-156页

作者： MENG SEN LI, PING FENG LI, FBI YI YANG, SHI PENG HE, Guo GUANG DU, GANG LI1 Department of Biochemistry and molecular Biology, 2.Department of Biophysics, Health Science center, Peking {2., beijing 100083, china Department of Biochemistry and molecular Biology Health Science Center Peking University Beijing China Department of Biophysics Health Science Center Peking University Beijing China

AIM The existence and properties of alpha-fetoprotein (AFP) receptor on the surface of NIH 3T3 cells and the effects of AFP on cellular signal transduction pathway were investigated. METHODS The effect of AFP on the proliferation of NIH 3T3 cells was measured by incorporation of 3H-TdR. Receptor-binding assay of 12.I-AFP was performed to detect the properties of AFP receptor in NIH 3T3 cells. The influences of AFP on the [cAMP]i and the activities of protein kinase A (PKA) were determined. Western blot was used to detect the change of K-ras P2. protein expression. RESULTS The proliferation of NIH 3T3 cells treated with 0-80 mg/L of AFP was significantly enhanced. The Scatchard analysis indicated that there were two classes of binding sites with KD of 2.72.×10-9M (Bmax=12.10 sites per cell) and 8.931× 10-8M (Bmax=119700 sites per cell) respectively. In the presence of AFP (2. mg/L), the content of cAMP and activities of PKA were significantly elevated . The level of K-ras P2. protein was upregulated by

关键词： Alpha-fetoprotein receptor signal transduction monoclonal antibody gene expression.

Theoretical Study of the Abnormal Fine Structures and Forbidden Transitions of OⅡ

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Theoretical Study of the Abnormal Fine Structures and Forbid...

Subchronic toxicological effects of aquatic nitrobenzene on Medaka and Chinese rare minnow

第四届全国青年计算物理学术会议

作者： ShaoHao Chen, JiaMing Li (Key Laboratory of atomic and molecular {2. of Education Ministry, Department of Physics, tsinghua university, beijing 100084. china) (Department of Physics, Shanghai Jiaotong university, Shanghai 2.0030, china)

Singly ionized oxygen (OⅡ) is a rich species in many nebulae, therefore it is of great interest in astronomy and astrophysics. There are five fine-structure terms of the ground-state configuration(1s2.s2.p3), i.e.,

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Science china Chemistry 2007年第5期50卷 707-717页

作者： ZHOU QunFang1, FU JianJie1,2. MENG HaiZhen1,2. ZHU XueYan1,2. JIANG GuiBin1, ZHANG JianBin1, LIU JieMin2.& SHI GuoQing2.1 State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research center for Eco-environmental Sciences, Chinese Academy of Sciences, beijing 100085, {2. 2.Department of Chemistry, School of Applied Science, university of Science and Technology beijing, beijing 100083, {2. State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing China Department of Chemistry School of Applied Science University of Science and Technology Beijing Beijing China

Based on the simulative exposure experiments of nitrobenzene to two small experimental fishes, Medaka (Oryzias latipes) and Chinese Rare Minnow (Gobiocypris rarus), it was found that nitrobenzene could decrease in a linear way in the static aquatic system. Both fishes could accumulate dose-related levels of nitrobenzene quickly and eliminate the compound rapidly when they were transferred to clean water. The Chinese rare minnow showed more sensitivity to the acute toxicity exposure of nitrobenzene than Medaka. Typical molecular biomarkers in oxidative defense system including superoxide dismu- tase (SOD), catalase (CAT) showed the chemical induced alterations. The changes of acetylcholi- nesterase (AChE) activities indicated that nitrobenzene might affect the normal neural function. Nitro- benzene exposure could also lead to obvious damaging effects on the target organs, such as gill and liver by hitopathological studies.

关键词： nitrobenzene, Medaka, Chinese rare minnow, bioaccumulation, elimination, molecular biomarkers, histopathological effects

Shell effect and capture cross sections in the synthesis of superheavy nuclei

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1489-1493页

作者： DU SaiSai1,2.BIAN BaoAn1,2.3,LIU Min1,2.4,FENG ZhaoQing5,6 & ZHANG FengShou1,2.6 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,College of Nuclear Science and Technology,beijing Normal university,beijing 100875,china 2.beijing Radiation center,beijing 100875,china 3 School of Science,Jiangnan university,Wuxi 2.412.,china 4 College of Physics and Technology,Guangxi Normal university,Guilin 541004,china 5 Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,china 6 center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing China beijing Radiation center Beijing China School of Science Jiangnan University Wuxi China College of Physics and Technology Guangxi Normal University Guilin China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The shell effect is included in the improved isospin dependent quantum molecular dynamics model in which the shell correction energy of the system is calculated by using the deformed two-center shell model. A switch function is introduced to connect the shell correction energy of the projectile and the target with that of the compound nucleus during the dynamical fusion process. It is found that the calculated capture cross sections reproduce the experimental data quantitatively at the energy near the Coulomb barrier. The capture cross sections for reaction 35 80 Br + 82.2.8 Pb → 117 2.8 X are also calculated and discussed.

关键词： superheavy nuclei transport theory shell effect cross sections

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

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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.eking-Yale Joint {2. of Plant molecular Genetics and Agrobiotechnology,College of Life Sciences,Peking university,beijing 100871,china ~3Department of molecular,Cellular,and Developmental Biology,Yale university,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

Nanomechanical Properties of molecular Deposition Film

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Journal of Wuhan university of Technology(Materials Science) 2005年第3期20卷 20-22页

作者：兰惠清 School of Mechanical Electronic and Control Engineering Beijing Jiaotong University

Two nanomechanical properties of the moleculor deposition （ MD ） film deposited on the Au substrate were studied. The first is its nanotribological property investigated by an atomic force microscope, which indicates that the deposition of the MD film could reduce the frictional force. The second is its nanoindent property studied by a nano-indenter. The results show that, after the MD film is deposited on the Au substrate , the elastic modulus, hardness and load decreased all, moreover, the elastic deformation increased and the plastic deformation decreased, which indicates that the MD film can improve the nanomechanical properties of the Au substrate.

关键词： molecular deposition film atomic force miroscope nanomechanical properties nanoindent

Heavy ion reactions around the Coulomb barrier

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2. ZHANG GaoLong1,3, YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 china Institute of atomic Energy, P. O. Box 2.5(10), {2. 102.13, china 2.Particle Astrophysics center, Institute of High Energy Physics, Chinese Academy of Sciences, {2. 100039, china 3 School of Physics and Nuclear Energy Engineering, Beihang university, {2. 100191, china china Institute of atomic Energy Beijing China Particle Astrophysics center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of Physics and Nuclear Energy Engineering Beihang University Beijing China

The angular distributions of fission fragments for the 32.+184W reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 32.+90,96Zr in an energy range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 32.+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+2.8Pb, 196Pt, 184W, and 154,152.m at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12. at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 2.% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

A Comparative Study of Tribological Properties between Perfluoro and Non-perfluoro Alkylsilane Self-assembled Monolayers(SAMs)

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Journal of Wuhan university of Technology(Materials Science) 2009年第4期24卷 588-593页

作者：王新宽刘宇宏 State Key Laboratory of Tribology Tsinghua University

The tribological properties of perfluoro and non-perfluoro alkylsilane molecular films were investigated and compared detailedly. Their surface properties were characterized by X-ray photoelectron spectroscopy （XPS）, atomic force microscopy （AFM） and contact angle （CA） measurement. A ball-on-disk tribometer was used to study the frictional properties of these alkylsilane monolayers. The experimental results reveal that the alkylsilane molecular films are good candidates to decrease friction and they have good capability to endure rigorous shear forces. Perfluoro alkylsilane molecular films are bonded better with the Si substrate than the simple hydrocarbon ones. The effects of sliding velocity and normal load on friction coefficient are evident and the friction coefficient in- creases with the increase of the sliding velocity. However, friction coefficient decreases with the increase of normal load initially and then increases, indicating there exists a critical normal load for the load effect.

关键词： perfluoroalkylsilane XPS AFM friction coefficient