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From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials

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Journal of Materials Science & Technology 1999年第4期15卷 315-319页

作者： Shaojun LIU(Department of physics, Beijing Normal University, Beijing 100875, China)Xiaobo WEI(Department of Physics, Liuzhou College of Education, Liuzhou 545005, China)Zhaodou chen Jun CAI and Benkun MA(Department of Physics, Beijing Normal University, Department of Physics Beijing Normal University Beijing 100875 China Department of Physics Liuzhou College of Education Liuzhou 545005 China

In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.

关键词： Rev Li chen From the Green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body

TOTAL SYNTHESIS OF YEAST ALANINE TRANSFER RIBONUCLEIC ACID

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Science in China,Ser.B 1983年第5期26卷 464-481页

作者：王德宝郑可沁裘慕绥梁镇和吴仁龙陈常庆汪恩壁朱莹书申庆祥余允华汪猷陈海宝杨再完陆蕴华陈慎王贵海胡美浩 Shanghai Institute of Biochemistry Academia Sinica Shanghai Institute of Cell Biology Shanghai Institute of Organic Chemistry Institute of Biophysics Beijing Department of Biology Peking University

By a combination of chemical and enzymatic methods, small oligonucleotides with lengths varying from 2 to 8 nucleotides were synthesized from mononucleotides. The small oligonucleotides were then ligated with T4 RNA ligase into six laxge ligonucleotides （9 to 19 nucleotides long） which were further ligated to form two half molecules with 35 and 41 nucleotides respectively, Finally, the two synthetic half molecules were annealed and ligated to obtain the whole molecule of yeast alanine tRNA (tRNAyAla). Prior to this, two semi-syntheses were performed, i. e. ligation of the synthetic 5’-half molecule with the natural 3’-half molecule and that of the natural 5’-half molecule with the synthetic 3’-half molecule.

关键词： In tRNA TOTAL SYNTHESIS OF YEAST ALANINE TRANSFER RIBONUCLEIC ACID chen OC

Study on an Explosion Treated Steel Weld Metal with Prepared Crack

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Journal of Materials Science & Technology 2001年第3期17卷 385-387页

作者： Xiaonan GUO and Xin LONG School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China Huaining chen and Liangshan chen Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China Guangjun GAI Depa Sch. of Mat. Sci. and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

A softening zone with recrystallized grain around the prepared crack tip in the shock waves treated C-Mn steel weld metal was observed. It is suggested that a dynamic recovery occurred around the prepared crack tip even at a low explosion pressure (5 GPa) because of the stress and strain concentration at the crack tip when shock waves pass through. This result supports the previous work on the improved mechanical properties of a shock treated welded joint with residual crack from the viewpoint of microstructure.

关键词： Study on an Explosion Treated Steel Weld Metal with Prepared Crack very high chen

Effects of Spinach Powder Fat-Soluble Extract on Proliferation of Human Gastric Adenocarcinoma Cells

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Biomedical and Environmental Sciences 1999年第4期12卷 247-252页

作者： HETAO HUANGchenG－YU 等 DepartmentofNutritionandFoodHygiene SchoolofPublicHealthWestChinaUniversityofMedicalSciences Departm

Four kinds of assays were used to study the effect of a fat-soluble extract of spinach powder (SPFE) on the proliferation of human gastric adenocareinoma cell line (SGC-7901) in vitro.These studies included: (Ⅰ) cell growth assay, (Ⅱ) colony forming assay, (Ⅲ) MTT colorimetric assay, and (Ⅳ) 3H-TdR incorporation assay. The concentrations of SPFE expressed as the level of β-carotene in the medium were 2×10-8, 2×10-7 and 2×10-6 mol/L β-carotene in assays (Ⅰ)～(Ⅲ), but 4×10- 8, 4×10-7 and 4×10-6 mol/L β-caretene in assay (Ⅳ) respectively. The results indicated that SPFE inhibited the prolifendion and colony forming ability of SGC-7901 cells. And in MTT assay, SPFE inhibited the viability of SGC7901 cells, but no inhibitory effect of SPFE was observed on the viability of lymphocytes in peripheral blood of healthy people. Finally, in the 3H-TdR incorporation test, both SPFE and β-carotene showed significant inhibitory effects on DNA synthesis in SGC-7901 cells, but SPFE was more effective than β-carotene.

关键词： SGC chen cell line Effects of Spinach Powder Fat-Soluble Extract on Proliferation of Human Gastric Adenocarcinoma Cells

Phase Relations in TiAl+Nb System

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Journal of Materials Science & Technology 1994年第5期10卷 359-366页

作者： Jingguo WANG Guoliang chen and Zuqing SUN (State Key Lab. for Advanced Metal Materials, University of Science and Technology Beijing, Beijing, 100083, China)Hengqiang YE (Lab. of Atomic Imaging of Solids, Institute of Metal Research, Academia Sinica, Sh Univ of Science and Technology Beijing China

The microstructures and phases of ternary TiAl+Nb alloys containing 50-60 at.-%Al, 0-21 at.-%Nb have been studied using transmission electron microscopy (TEM) and X-ray powder diffraction. The phases present in the alloys and their distribution were found to be a sensitive function of composition. The phase relations between γ-TiAl and γ1 (a new ordered ternary intermetallic compound based on γ-TiAl) were determined. Essentially single γ phase was determined for alloys with relativety low Nb content (≤10 at.-%Nb). the γ1 phase was determined to exist in the composition range containing higher Nb contents (15-21 at.-%Nb). Between γ and γ1 phases, with intermediate Nb contents there is a transitional phase γ1 (a superstructure of γ-TiAl). As for the influence of Al concentration on the phase relations. the γ1 phase was inclined to form in the alloys with relatively high Al contents. The ordering transformation of γ, to γ1 is a continuous ordering process and the transition may be second order.

关键词： TiAl nm PA Phase Relations in TiAl+Nb System chen

On the Formability of Some Metastable Alloy Phases

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Journal of Materials Science & Technology 1994年第1期10卷 23-26页

作者： Bo TANG Deshan KANG Pei QING Weiming ZHANG and Nianyi chen(Shanghai Institute of Metallurgy, Chinese Academy of Sciences, Shanghai, 200050, China) Shanghai Inst of Metallurgy Shanghai China

Pattern recognition and neural network methods have been used to investigate the formability of metastable alloy phases, It has been found that some chemi cal bond parameters Such as valence electron number, electronegativity and metallic radii of cor-nponent elements are the dominating fac tors affecting metastable alloy phase formation. Some semi-empirical rules found in this way may be useful for the construction of expert system for materials design.

关键词： Figure Cd Ni On the Formability of Some Metastable Alloy Phases chen Pb Sn Ta

Deformation and Dislocation Structure in L1_2 Titanium Trialuminide Alloys

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Journal of Materials Science & Technology 1994年第6期10卷 435-440页

作者： Gengxiang HU Shipu chen Xiaohua WU Yonghua RONG and Xiaofu chen(Dept. of Materials Science, Shanghai Jiao Tong University, Shanghai, 200030, China) Shanghai Jiao Tong Univ Shanghai China

The deformation behaviour and the nature of dislocations of the Al3Ti-base L12 alloya modified with Fe and Mn etc, were investigated. The results show that the deformation and fracture character istics are closely related to the alloy compositions. The effect of hot-working process on the room tem perature ductility is remarkable, not only resulting in an appreciable improvement of compressive properties but also showing a 0.28% plastic strain in tensile test. The SISF dissociation of a dislocations on {111} planes was found at room temperature. The determined dissociation scheme is consistent with the mechanical behaviour of these alloys in the lower temperature region.

关键词： Ti chen Deformation and Dislocation Structure in L12 Titanium Trialuminide Alloys

Proteomic dissection of biological pathways/processes through profiling protein-protein interaction networks

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Science China Chemistry 2010年第4期53卷 737-746页

作者： chen Xian Institutes for Biomedical Sciences, Fudan University, Shanghai 200433, China Department of Biochemistry & Biophysics, School of Medicine, University of North Carolina-Chapel Hill, USA Institutes for Biomedical Sciences Fudan University Shanghai China Department of Biochemistry & Biophysics School of Medicine University of North Carolina-Chapel Hill Chapel Hill USA

Cellular functions, either under the normal or pathological conditions or under different stresses, are the results of the coordinated action of multiple proteins interacting in macromolecular complexes or assemblies. The precise determination of the specific composition of protein complexes, especially using scalable and high-throughput methods, represents a systematic approach toward revealing particular cellular biological functions. In this regard, the direct profiling protein-protein interactions (PPIs) represent an efficient way to dissect functional pathways for revealing novel protein functions. In this review, we illustrate the technological evolution for the large-scale and precise identification of PPIs toward higher physiologically relevant accuracy. These techniques aim at improving the efficiency of complex pull-down, the signal specificity and accuracy in distinguishing specific PPIs, and the accuracy of identifying physiological relevant PPIs. A newly developed streamline proteomic approach for mapping the binary relationship of PPIs in a protein complex is introduced.

关键词： chen Proteomic dissection of biological pathways/processes through profiling protein-protein interaction networks

Synthesis and Diastereomeric Analysis of Uridine 2’,3’-Cyclic Phosphite

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Chinese Chemical Letters 1997年第3期8卷 199-202页

作者： Yun DING Yi Bing ZHANG Yao Quan chen (Laboratory of Bio-organic & Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences, Shanghai 200032) Lab. Bio-Organ. and Nat. Prod. Chem. Shangliai Inst. of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Uridine 2’,3’-cyclic phosphite has been synthesized and the diastereomers were analysed by 2D NMR technique to assign the configuration

关键词： chen Synthesis and Diastereomeric Analysis of Uridine 2 Cyclic Phosphite