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Thermal expansion properties and hygro-scopicity of Y_(2-x)Sm_xW_3O_(12) (x=0.0-0.4) compounds

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Science china(Technological sciences) 2008年第1期51卷 25-32页

作者： YU ZhouXiang1, PENG Jie2, WANG Hui2, WU MeiMei2, CHENG YingZhi2, HU ZhongBo2 & CHEN DongFeng1 1 china institute of atomic Energy, P.O. Box 275 (30), Beijing 102413, china 2 College of Chemistry and Chemical Engineering, Graduate University of Chinese Academy of sciences, Beijing 100049, china china institute of atomic Energy Beijing China College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China

A novel class of solid solutions of Y2-xSmxW3O12 (x = 0.0–0.4) were synthesized and studied by means of powder X-ray diffraction. All samples crystallize in an ortho- rhombic space group Pnca. The lattice parameters a, b and c of Y2-xSmxW3O12 in- crease with increasing Sm content. Since the compounds of this series hydrate at room temperature, thermogravimetric (TG) analysis was carried out. The result shows that the compound stores less water with increasing Sm content. The thermal expansion properties of Y2-xSmxW3O12 (x = 0.1, 0.3 and 0.4) were investi- gated with high temperature X-ray diffraction. Negative thermal expansion coeffi- cient αl becomes less negative from -6.644×10-6 to -6.211×10-6℃-1 when x changes from 0.1 to 0.4.

关键词： rare earth tungstates negative thermal expansion hygroscopic XRD

A Fast Algorithm for Phase Grating Preparation by Real Space Method

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Journal of Materials Science & Technology 2001年第2期17卷 240-242页

作者： Qiuxiang LIU and Yuanming WANG Laboratory of atomic Imaging of Solids, institute of Metal Research, Chinese Academy of sciences, Shengyang 110015, china Qibin YANG and Xiaohong YAN institute of Modern Physics, Xiangtan University, Xiangtan 411105, china Lab. of atomic Imaging of Solids Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110015 China

Making use of this expression to calculate the phase grating in high resolution image simulation can greatly reduce the calculating time. In this paper, the derivation of the expression is introduced, and then the computer routine is explained in details. Finally the potential projection map of Mg44Rh7 along [001] direction is shown as an illustration. All operations are carried out in real space, so we call the calculation method as the real space method.

关键词： A Fast Algorithm for Phase Grating Preparation by Real Space Method

Functional Analysis of Multiple Transcription Factor Sites in a Regulatory Element of Human ε-Globin Gene

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Acta Biochimica et Biophysica sinica 2004年第10期36卷 673-680页

作者： Chun-Hui HOU, Jian HUANG, and Ruo-Lan QIAN* State Key Laboratory of molecular Biology, institute of Biochemistry and Cell Biology, Shanghai institutes for Biological sciences, Chinese Academy of sciences, Graduate School of the Chinese Academy of sciences, Shanghai 200031, china State Key Laboratory of molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China

The developmental control of the human ε-globin gene expression is mediated by transcrip- tional regulatory elements in the 5’ flanking DNA of this gene. A previously identified negative regulatory element (–3028 to –2902 bp, termed ε-NRAII) was analyzed and one putative NF-κB site and two GATA sites locate at –3004 bp, –2975 bp and –2948 bp were characterized. Electrophoresis mobility shift assay (EMSA) showed that the putative NF-κB site was specifically bound by nuclear proteins of K562 cells. Data obtained from transient transfection showed that the expression of reporter gene could be upregulated about 50% or 100% respectively when ε-NRAII was inserted upstream of the SV40 promoter or ε-globin gene proximal promoter (–177 bp to +1 bp), suggesting that ε-NRAII might not be a classic silencer. Mutation in the putative NF-κB site or in the GATA site (at –2975 bp) slightly reduced the expression of reporter gene driven by SV40 promoter or ε-globin gene proximal promoter. However, the mutation of GATA site at –2948 bp remarkably reduced the reporter gene activity driven by SV40 promoter, but not by ε-globin gene proximal promoter. Further mutation analysis showed that the negative effect of mutation in GATA site at –2948 bp on SV40 promoter was not affected by the mutation of the putative NF-κB site, whereas it could be abolished by the mutation of GATA site at –2975 bp. Furthermore, the mutation of both GATA sites could synergistically reduce the reporter gene activity driven by ε-globin gene proximal promoter. Those results suggested that ε- NRAII might function differently on the SV40 promoter and ε-globin gene proximal promoter.

关键词： ε-globin gene regulatory element NF-κB GATA

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural Science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2 , Zhang Yong3 and Long Guilu1,2(1. Key Laboratory for atomic and molecular Nanosciences, and Department of Physics, Tsinghua University, Beijing 100084, china 2. Center of Quantum Information Science and Technology, Tsinghua National Laboratory for information Science and Technology, Beijing 100084, china 3. institute of Physics, School of sciences, Beijing University of Posts and Telecommunications, Beijing 100876, china) Key Laboratory for atomic and molecular Nanosciences Department of Physics Tsinghua University Beijing 100084 China Center of Quantum Information Science and Technology Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

An Effective Method for Raising Antisera Against β-defensins: Double-copy Protein Expression of mBin1b in E. coli

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Acta Biochimica et Biophysica sinica 2004年第8期36卷 571-576页

作者： Li-Qing XIAO, Ai-Hua LIU, and Yong-Lian ZHANG State Key Laboratory of molecular Biology, institute of Biochemistry and Cell Biology, Shanghai institutes for Biological sciences, Chinese Academy of sciences, Graduate School of the Chinese Academy of sciences, Shanghai 200031, china State Key Laboratory of molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China

Bin1b is a rat epididymis specific β-defensin which may have fertility related functions in addition to its antimicrobial activity. β-defensins are cysteine-rich cationic antimicrobial peptides that have their important implications in innate and adaptive immunity. Though considerable numbers of new β-defensins have been discovered, few corresponding antibodies have been reported. The small peptide with special structure and antimicrobial nature of β-defensins make them very difficult to express in prokaryotic system. Here we adopted a double-copy protein expression scheme based on which not only the mBin1b protein was successfully expressed but also the immunity of the antigen was enhanced. The validity of the antisera was verified by using Western blotting and immunohistochemical analyses. It will be a useful tool for deeply investigating the roles of Bin1b and also provide a simple but effective method in raising antisera against other members of the β-defensin gene family.

关键词： Bin1b epididymis β-defensin double-copy protein polyclonal antiserum

Imaging the "missing" bands in the REMPI detection of CD3 radical

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Imaging the "missing" bands in the REMPI detection of CD3 ra...

Fabrication of Ni-decorated helical ribbon composite microstructure from self-assembled lipid tubule by electroless metallization

第九届全国化学动力学会议

作者： Bailin Zhang,Kopin Liu Institue of atomic and molecular sciences,academia sinica, P.O. Box 23-166, taipei, Taiwan 106

＜正＞Three small features were uncovered in the （2+1） REMPI spectra of CD3 produced from a crossed-beam reaction of F + CHD3 near reaction threshold. Taking the velocity mapped images of these features revealed several well-resolved ring-like structures. BY conservation of energy, these spectral features were unambiguously

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来源： cnki会议评论

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Science china Chemistry 2006年第3期49卷 238-245页

作者： FU Yubin1,2, ZHANG Lide1 & ZHENG Jiyong2 1. institute of Solid State Physics, china Academy of sciences, Hefei 230031, china 2. Luoyang Ship Material Research institute, Luoyang 471039, china institute of Solid State Physics China Academy of Sciences Hefei China Luoyang Ship Material Research institute Luoyang China

Lipid molecules can self-assemble into a tubular structure, which is formed by tightly wound helical ribbons. Lipid tubules are utilized as a precursor to fabricate a novel Ni-decorated helical ribbon composite microstructure in a high yield by electroless deposition. The microstructure carries Ni nanoparticles on the flat face and wires at the edge of helical ribbon, in which the average size of nanoparticles is about 40―60 nm, and the wires are of a layered structure strongly correlated with a multi-bilayer structure in the lipid membrane. Compared with the tubular precursor, the Ni-decorated composite microstructure becomes short and irregular shapes due to the breakage in the deposition, and its formation is largely bound up with the tubular helical structure and the different catalytic process. Finally, the helical composite microstructure would have a potential application in the development of electric active materials.

关键词： molecular self-assembly, lipid tubule, helical ribbon, electroless deposition, nanoparticles and wires, composite microstructure.

Effect of leukemia inhibitory factor on embryonic stem cell differentiation:implications for supporting neuronal differentiation

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Acta Pharmacologica sinica 2006年第1期27卷 80-90页

作者： Zhao HE~(2,3) Jing-jing LI~(2,3) Chang-hong ZHEN~(3,4) Lin-ying FENG~3 Xiao-yan DING~(2,5)2 Laboratory of molecular and Cell Biology and Laboratory of Stem Cell Biology,institute of Biochemistry and Cell Biology:Shanghai institutes for Biological sciences,Chinese Academy of sciences,Shanghai 200031,china 3 Shanghai institute of Materia Medica.Chinese Academy of sciences.Shanghai 201203,china 4 Graduate School of the Chinese Academy of sciences,Shanghai 200031,china. Laboratory of molecular and Cell Biology and Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai institutes for Biological sciences Chinese Academy of Sciences Shanghai China Shanghai institute of Materia Medica Chinese Academy of Sciences Shanghai China Graduate School of the Chinese Academy of sciences Shanghai China

Aim:Leukemia inhibitory factor (LIF),a pleiotropic cytokine,has been used ex-tensively in the maintenance of mouse embryonic stem cell *** thiscurrent work,we examined the effect of the LIF signaling pathway in embryonicstem (ES) cell differentiation to a neural ***:In the presence of LIF(1000U/mL),the production of neuronal cells derived from embryoid bodies (EB)was tested under various culture *** of the LIF pathway wasexamined with specific *** effects of cell apoptosis and proliferationon neural differentiation were *** cell differentiation into three-germlayers was ***:Under various culture conditions,neuronal differ-entiation was increased in the presence of *** the LIF-activated STAT3signaling pathway with specific inhibitors abolished the neuronal differentiationof ES cells,whereas inhibition of the LIF-activated MEK signaling pathway im-paired the differentiation of ES cells toward a glial *** suppressed cellapoptosis and promoted cell proliferation during ES cell *** inhib-ited the differentiation of ES cells to both mesoderm and extraembryonic endo-derm fates,but enhanced the determination of neural ***:These results suggest that LIF plays a positive role during the differentiation ofES cells into neuronal cells.

关键词： leukemia inhibitory factor embryonic stem cells neural fate embryoid bodies

MB_8^(2-) (M=Be,Mg,Ca,Sr,and Ba):Planar octacoordinate alkaline earth metal atoms enclosed by boron rings

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Science china Chemistry 2010年第8期53卷 1737-1745,1829-1832页

作者： PU ZhiFeng1,GE MaoFa1 & LI QianShu2 1State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for molecular sciences (BNLMS) institute of Chemistry,Chinese Academy of sciences,Beijing 100190,china 2Center for Computational Quantum Chemistry,South china Normal University,Guangzhou 510631,china State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for molecular sciences (BNLMS) institute of Chemistry Chinese Academy of Sciences Beijing China Center for Computational Quantum Chemistry South China Normal University Guangzhou China

Complexes involving planar octacoordinate alkaline earth metal atoms in the centers of eight-membered boron rings have been investigated by two density functional theory (DFT) ***82-with D8h symmetry is predicted to be stable,both geometrically and electronically,since a good match is achieved between the size of the central beryllium atom and the eight-membered boron *** contrast,the other alkaline earth metal atoms cannot be stabilized in the center of a planar eight-membered boron ring because of their large *** following the out-of-plane imaginary vibrational frequency,pyramidal C8v MgB82-,CaB82-,SrB82-,and BaB82-structures are *** presence of delocalized π and σ valence molecular orbitals in D8h BeB82-gives rise to aromaticity,which is reflected by the value of the nucleus-independent chemical *** D8h BeB82-structure is confirmed to be the global minimum on the potential energy surface.

关键词： density functional theory octacoordinate alkaline earth metal aromatic molecular orbital