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Progress in Natural Science:Materials International 2007年第2期17卷 177-186页

作者： QI Guowei, zhang Jinjiang , WANG Xinshe and GUO Lei ( Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, china School of Earth and Space sciences, peking university, beijing 100871, china Institute of Geology, Chinese Academy of Geological sciences, beijing 100037, china) Key Laboratory of Orogenic Belts and Crustal Evolution MOE School of Earth and Space Sciences Peking University Beijing 100871 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Three large-scale thrusts developed in the Daqingshan orogen, Inner Mongolia, with a northeast-east trending from Louhuashan to Suletu are described in this paper. These northwest-directed thrusts, together with the four tectonic belts (or tectonic sheets) separated by these faults, formed a typical thrusting system. The originally defined Hohhot metamorphic core complex may be a tectonic sheet, making the uppermost tectonic unit of the thrusting system and truncated by the Daqingshan detachment fault on top. The existing tectono-chronological studies showed that the thrusting of this region possibly happened at the same time as the extension along the top detachment fault. This presents that the contraction and extension in Daqingshan orogen were probably simultaneous. The structural pattern of the Daqingshan orogen can be correlated to the Himalayan orogen, and models for simultaneous thrusting and detachment in Himalaya may give a hint for explaining the development of the Daqingshan orogen.

关键词： Daqingshan thrust metamorphic core complex detachment fault contraction-extension transform Himalaya.

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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Science china Chemistry 2007年第3期50卷 308-317页

作者： zhang Wen, ZHAO Fei, LIU Tao & GAO Song beijing National Laboratory for Molecular sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, college of Chemistry and Molecular Engineering, peking university, beijing 100871, china beijing National Laboratory for Molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing China

A series of 1D nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2Ln(NO3)3]n·solvents (HL = bis(2-pyridylcarbonyl)amine; M = Ni, Ln = Gd (1·NiGd), Tb (2·NiTb), Dy (3·NiDy), Ho (4·NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2O or H2O-ethanol), was synthesized and characterized. All of the complexes are isostructural at 293 K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1―9, where weak ferromagnetic interaction is found in 1·NiGd, ferromagnetic interaction in 2·NiTb and 3·NiDy, and antiferromagnetic interaction in 4·NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3d-4f coordination polymer magnetic property

SYNTHESIS AND PROPERTIES OF LIQUID CRYSTAL POLYSILOXANES WITH MESOGENIC STILBENE SIDE GROUPS

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Chinese Journal of Polymer Science 2000年第2期18卷 95-99页

作者： Dong zhang Yan-tao Zhu Da-hui Zhao Xin-hua Wan Qi-feng Zhou Department of Polymer Science & Engineering, college of Chemistry, peking university, beijing 100871, china 北京大学北京

A variety of mesomorphic side-chain polysiloxanes were synthesized by using hydrosilylation reaction with dicyclopentadienylplatinum(II) (DPPC) as the catalyst. The mesogenic groups are derivatives of stilbene with cyano or nitro tail groups. The products were characterized by DSC, X-ray diffraction and polarizing optical microscopy (POM). All the polymers were found to have relatively low T-g and can form a smectic liquid crystal phase.

关键词： liquid crystal polymer polysiloxane

Recent progress in the study of intracellular toxicity of amyloid P peptide in Alzheimer's disease

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Progress in Natural Science:Materials International 2007年第3期 233-236页

作者： zhang Yan and YU Longchuan (college of life sciences, peking university, beijing 100871, china)

Amyloidβ(Aβ) deposition is one of the major pathological markers of Alzheimer’s disease (AD). Extracellular Afi toxi-city has been studied for a long time in AD research field. However, controversial data show that extracellular Aβload does not correlate with the dementia levels of AD patients and extracellular Aβonly induces significant cell death at non-physiological high concentrations. With the evolvement of Afi hypothesis, considerable attention has been devoted to the study of intracellular Aβtoxicity recently. Intracellular Aβinduces dramatic cell loss in AD transgenic models and in human primary neurons (at pM concentrations) through p53, Bax and caspase-6 pathways. Here, we review the generation, toxicity and possible pathways of intracellular Aβtoxicity, and discuss the implication and current knowledge of intracellular Aβin neuronal cell loss in neurodegenerative diseases.

关键词： Alzheimer’s disease amyloid P peptide neruonal loss.

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural Science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3**) Zheng Shili~2 zhang Mei~1 zhang Yi~2 (1.Department of Physical Chemistry,university of Science and Technology beijing,beijing 100083,china 2.Institute of Process Engineering,Chinese Academy of sciences,beijing 100080,china 3.college of Engineering,peking university,beijing 100871,china) Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 China college of Engineering Peking University Beijing 100871 China Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2O4-KOH-O2of oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2CrO4-H2O,KOH-KAlO2-H2O, K（Na）OH-K（Na）2CO3-H2O,K（Na）OH-K（Na）HCO3-H2O and K（Na）HCO3-K（Na）2CrO4-H2O have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2O4can be oxidized across a wide range of temperature;K（Na）2CrO4can be separated from K（Na）AlO2system at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2CrO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

The CXXC finger 5 protein is required for DNA damage-induced p53 activation

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Science china(life sciences) 2009年第6期52卷 528-538页

作者： zhang Min1,WANG RuiPeng1,WANG YanYi 2,DIAO FeiCi1,LU Fei1,GAO Dong1,CHEN DanYing 1,ZHAI ZhongHe1 & SHU HongBing2 1 college of life sciences,peking university,beijing 100871,china 2 college of life sciences,Wuhan university,Wuhan 430072,china college of life sciences Peking University Beijing China college of life sciences Wuhan University Wuhan China

The tumor suppressor p53 is a critical component of the DNA damage response pathway that induces a set of genes responsible for cell cycle arrest,senescence,apoptosis,and DNA *** ataxia te-langiectasia mutated protein kinase(ATM) responds to DNA-damage stimuli and signals p53 stabiliza-tion and activation,thereby facilitating transactivation of p53 inducible genes and maintainence of genome *** this study,we identified a CXXC zinc finger domain containing protein termed CF5 as a critical component in the DNA damage signaling ***5 induces p53 transcriptional activity and apoptosis in cells expressing wild type p53 but not in p53-deficient *** of CF5 in-hibits DNA damage-induced p53 activation as well as cell cycle ***,CF5 physically interacts with ATM and is required for DNA damage-induced ATM phosphorylation but not its recruitment to *** findings suggest that CF5 plays a crucial role in ATM-p53 signaling in response to DNA damage.

关键词： p53 ATM DNA damage apoptosis

The Study of Anti-tumor Activity of Trichosanthin by Cyclic Voltammogram

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Chinese Chemical Letters 2000年第7期11卷 597-600页

作者： Gang XU Cheng Cai AN Jun FENG Yun Xiang CI Jin Hua TIAN zhang Liang CHENI( National Laboratory of Protein Engineering and Plant Genetic Engineering, college of life sciences, peking university, beijing 100871college of Chemistry and Molecular Engineeri Natl. Lab. Protein Eng. Plant G. College of Life Sciences Peking University Beijing 100871 China Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

The anti-tumor activity of Trichosanthin (TCS) has been frequently reported in recent years. In our experiments, electrochemical methods were applied to detect the effects of TCS on human leukemia cells U937. 50 mu g/ml TCS treatment for 40 hours can cause irreversible negative effects on the viability of U937 cells. This effect largely depends on the concentration of TCS and the time period of treatment.

关键词： Trichosanthin (TCS) U937 cells cyclic voltammogram Ribosome Inactivating Proteins (RIPs)

Thermodynamic evaluation and hydrothermal preparation of K_xNa_(1-x)NbO_3

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Rare Metals 2008年第4期27卷 371-377页

作者： zhang Ci LV Haijun GUO Min zhang Mei WANG Xidong Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 China college of Engineering. peking university Beijing 100871 China

The Gibbs free energies of reaction △rGτ of KNbO3 and NaNbO3 were calculated and then that of KxNa1-xNbO3 was estimated. On the basis of the thermodynamic calculation results, the hydrothermal temperatures were designed at 100, 160, and 230℃ respectively. However, NaNbO3 was prepared when the heating temperature was higher than 160℃, and KNbO3 and KxNa1-xNbO3 were obtained at 230℃, suggesting that only at a higher temperature the kinetic requirement is satisfied. According to the X-ray diffraction results, both the solid solutions, NaNbO3-based solid solution, Na1-xKxNbO3, and KNbO3-based solid solution, K1-xNaxNbO3, were hydrothermally synthesized in 6 mol/L alkali （NaOH and KOH） solution at 230℃.

关键词： KNbO3 NaNbO3 thermodynamic calculation hydrothermal synthesis Gibbs free energy

Preparation and properties of a nano TiO_2/Fe_3O_4 composite superparamagnetic photocatalyst

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Rare Metals 2009年第5期28卷 423-427页

作者： LI Yuxiang zhang Mei GUO Min WANG Xidong School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China college of Engineering Peking University Beijing 100871 China

Nano TiO2/Fe3O4 composite particles with different molar ratios of TiO2 to Fe3O4 were prepared via sol-gel method. X-ray diffraction, transmission electron microscopy, and vibration sample magnetometry were used to characterize the TiO2/Fe3O4 particles. The photocatalytic activity of the particles was tested by degrading methyl blue solution under UV illumination （254 nm）. The results indicate that with the content of TiO2 increasing, the photocatalytic activity of the composite particles enhances, while the magnetism of the particles decreases. When the molar ratio of TiO2 to Fe3O4 is about 8, both the photocatalytic activity and magnetism of the TiO2/Fe3O4 particles are relatively high, and their photocatalytic activity remains well after repeated use.

关键词： photocatalysis superparamagnetism sol-gel method TiO2 Fe3O4

Template-free hydrothermal synthesis of single-crystalline SnO_2 nanocauliflowers and their optical properties

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Rare Metals 2009年第5期28卷 449-453页

作者： WANG Yali GUO Min zhang Mei WANG Xidong School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China college of Engineering Peking University Beijing 100871 China

Large-scale single-crystalline SnO2 nanocauliflowers were successfully synthesized using a hydrothermal growth method without any template. The samples were characterized by X-ray diffraction （XRD）, field-emission scanning electron microscopy （FE-SEM）, en- ergy-dispersive X-ray spectroscopy （EDS）, transmission electron microscopy （TEM）, and selected area electron diffraction （SAED）. FE-SEM images show that the as-grown SnO2 nanocauliflowers are constructed of tetragonal prisms with a width of 500-600 nm. XRD, EDS, and SAED results indicate that the as-grown SnO2 nanocauliflowers are single crystalline with the tetragonal rutile crystalline structure. The growth mechanism of SnO2 nanocauliflowers is also preliminarily discussed on the basis of different Sn（OH） 62- concentrations, and it is found that Sn（OH） 62- concentration plays an important role in determining the shape of the prepared SnO2. Room temperature photoluminescence was further carried out on SnO2 nanocauliflowers to investigate their optical properties. An intense blue luminescence centered at a wavelength of 424 nm is observed in the as-grown SnO2 nanocauliflowers.

关键词： nanocauliflowers SnO2 hydrothermal photoluminescence