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Microstructure of the Ductile Phase in Intermetallic Compound Ni_(50)Al_(20)Fe_(30)

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Journal of Materials Science & Technology 1994年第5期10卷 341-346页

作者： Lianlong HE Shuhe WANG Jianting GUO and Hengqiang YE (Lab. of atomic Imaging of Solids, institute of Metal Research, academia sinica, Shenyang, 110015, china)(To whom correspondence should be addressed) Lab of atomic Imaging of Solids Shenyang China

The microstructure of the single hot extruded and annealed Ni50Al20Fe30Y0.003 intermetallic compound alloys has been examined by means of high resolution electron microscopy (HREM). In these extruded and annealed alloys. the ductile phase is of a mixture of the disordered fcc γ matrix and or dered γ' precipitates. This fact well interprets the reason why the degree of annealing treatment can influence the strength and ductility of these alloys. The HREM observation revealed directly that there was some strain concentration at γ'-γ interfaces, due to the presence of more iron atoms in these two phases. The fixed orientation relationship between the γ phase and γ' precipitates was identified to be {001}γ||{00 }γ' and γ|| γ'

关键词： Fe Figure Microstructure of the Ductile Phase in Intermetallic Compound Ni Al

SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR BRANCHED POLYETHYLENE

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Chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 State Key Laboratory of Engineering Plastics The Center for molecular sciences institute of Chemistry Chinese Academy of sciences Beijing 100080 china The Center for molecular sciences Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Engineering Plastics 北京 100080

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2ZrCl_2 Silica supported catalysts Branched polyethylene

Transiently Expressed Short Hairpin RNA Targeting 126 kDa Protein of Tobacco Mosaic Virus Interferes with Virus Infection

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Acta Biochimica et Biophysica sinica 2006年第1期38卷 22-28页

作者： Ming-Min ZHAO~(1,2),De-Rong AN~(1*),Jian ZHAO~2,Guang-Hua HUANG~3,Zu-Hua HE~4,and Jiang-Ye CHEN~3 ~1 College of Plant Protection,Northwest Science and Technology University of Agriculture and Forestry,Yangling 712100,china ~2 College of Agriculture,Yangtze University,Jingzhou 434025,china ~3 State Key Laboratory of molecular Biology,institute of Biochemistry and Cell Biology,Shanghai institutes for Biological sciences, Chinese Academy of sciences,Shanghai 200031,china ~4 State Key Laboratory of Plant molecular Genetics,institute of Plant Physiology and Ecology,Shanghai institutes for Biological sciences, Chinese Academy of sciences,Shanghai 200032,china College of Plant Protection Northwest Science and Technology University of Agriculture and Forestry Yang ling 712100 China College of Agriculture Yangtze University Jingzhou 434025 China State Key Laboratory of molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China State Key Laboratory of Plant molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

RNA-interference (RNAi) silences gene expression by'guiding mRNA degradation in asequence-specific *** interfering RNA (siRNA),an intermediate of the RNAi pathway,has beenshown to be very effective in inhibiting virus infection in mammalian cells and cultured plant ***,wereport that Agrobacterium tumefaciens-mediated transient expression of short hairpin RNA (shRNA) couldinhibit tobacco mosaic virus (TMV) RNA accumulation by targeting the gene encoding the replication-asso-ciated 126 kDa protein in intact plant *** results indicate that transiently expressed shRNA efficientlyinterfered with TMV *** interference observed is sequence-specific,and time-and *** expressed shRNA corresponding to the TMV 126 kDa protein gene did not inhibit cucumbermosaic virus (CMV),an unrelated *** order to interfere with TMV accumulation in tobaccoleaves,it is essential for the shRNA constructs to be infiltrated into the same leaves as TMV *** support the view that RNAi opens the door for novel therapeutic procedures against virus *** propose that a combination of the RNAi technique and Agrobacterium-mediated transient expressioncould be employed as a potent antiviral treatment in plants.

关键词： tobacco mosaic virus 126 kDa protein RNA interference short hairpin RNA

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...

CHEMICAL STRUCTURE DEPENDENCE OF THE INTERNAL ENERGY CONTRIBUTION IN RUBBER ELASTICITY

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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cnki会议

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Chinese Journal of Polymer Science 2001年第5期19卷 447-449页

作者： Juan Sun Xiao-zhen Yang Polymer Physics Laboratory Center for molecular sciences, institute of Chemistry Chinese Academy of sciences Beijing 100080 china 中科院化学所高分子物理及化学国家重点实验室北京

Conformational elasticity theory recently developed has been used to explore the internal energy contribution to the elastic force f(e)/f as a function of strain for poly(cis-1,4-isoprene) and poly(trans-1,4-isoprene). Calculated f(e)/f values are in good agreement with those obtained experimentally. Results show that behavior of f(e)/f is mainly contributed by chemical structure, or intramolecular interaction, supporting the experimental observations, and that the internal energy contribution is strain dependent.

关键词： conformational elasticity theory internal energy contribution poly(cis-1,4-isoprene) poly(trans-1,4-isoprene)

Full fermion-boson vertex function derived in terms of symmetry relations in Abelian gauge theory

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1206-1213页

作者： HE HanXin china institute of atomic Energy, Beijing 102413, china china institute of atomic Energy Beijing China

Nonperturbative studies such as confinement and dynamical chiral symmetry breaking need the nonperturbative interacting vertex functions. In this paper, an approach to determining the full fermion-boson vertex function in four-dimensional Abelian gauge theory is presented: this full vertex function is derived in terms of a set of normal (longitudinal) and transverse Ward-Takahashi relations for the fer-mion-boson (vector) and axial-vector vertices in the momentum space in the case of massless fermion. Such a derived fermion-boson vertex function should be sat-isfied both perturbatively and nonperturbatively. The fact that such a derived full fermion-boson vertex function to one-loop order holds indeed is proven and the nonperturbative form of this vertex is also under discussion.

关键词： symmetry Ward-Takahashi relations full fermion-boson vertex function

TRIMETHYLSILYLATED SILICA AS RHEOLOGY MODIFIER FOR SILICONE RESINS

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Chinese Journal of Polymer Science 2000年第1期18卷 51-55页

作者： Wei Huang Ying Huang Yunzhao Yu Center for molecular Science, institute of Chemistry, Chinese Academy of sciences, Beijing 100080, china 中科院化学所北京

Trimethylsilylated silica was synthesized. through hydrolytic condensation of tetraethoxysilane followed by trimethylsilylation. Rheological properties of the silicone resin with trimethylsilylated silica as modifier were studied. It turned out that the particle size of silica was important to the rheological behavior of the modified resin. Trimethylsilylated silica of medium particle size shows the strongest tendency of forming physical network in the resin.

关键词： silica trimethylsilylation rheology modifier silicone resins

SYNTHESIS　OF　BENZO－15－CROWN－5　PHENOL－FORMALDEHYDE　RESIN　FOR　LITHIUM　ISOTOPE　SEPARATION

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Chinese Chemical Letters 1996年第3期7卷 289-292页

作者： YOU Heng SHI Qun YAN Duo Yuan WANG Xiao Zhi ZHANG Zhong Guo DENG Hui Bao LU (institute of Photographic Chemistry, academia sinica, Beijing, 100101)(china institute of atomic Energy, Beijing, 102413) institute of Photographic Chemistry Academia Sinica Beijing 100101 china institute of atomic Energy Beijing 102413

Four kinds of phenol-formaldehyde resins containing benzo-15-crown-5 ether were synthesized for lithium isotope *** adsolptioncapacity and isotope effect of Liin these resins have been investigated. Singleseparation factors 1.023￣1.056 were obtained with batch method from isotoperatios, 6Li and Li'were enriched in tile resin phase and liquid phase, respectively.

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MICROSTRUCTURE OF SILICON CARBIDE WHISKERS

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Acta Metallurgica sinica(English Letters) 1991年第9期4卷 211-218页

作者： XU Haigang ZHU Jing YUAN Hong Central Iron and Steel Research institute,Ministry of Metallurgical Industry,Beijing,chinaNING Xiaoguang YE Hengqiang Laboratory of atomic Imaging of Solids,institute of Metal Research,academia sinica,Shenyang,china Central Iron and Steel Research Inst Beijing China

The morphology,crystal defects and chemical compositions of surfaces in two kinds of SiC whiskers related to their growth mechanism have been studied by means of electron microscopy and surface chemical *** upon the experimental results,five criteria for evaluating the whisker microstructure were suggested as:proportion of the perfect single crystals,morphology and dimensions,defects and their distribution,the bulk and surface chemistries,and crystallographic characteristics.

关键词： SiC whisker microstructure defect