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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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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 Chinese Acad Sci Polymer Phys Lab Ctr Mol Sci Inst Chem Beijing 100080 Peoples R China

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 102413 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

6-Membered ring intermediates in polymerization of N-carboxyanhydride-L-α-arginine in H_2O

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Science china Chemistry 2009年第8期52卷 1220-1226页

作者： XIN Liang1,REN Jie1,XIANG JunFeng2,YAN Qin1,XIE Yi1,WANG KongJiang1,LAI PingAn3 & BAI YaDuo3 1 institute of Biophysics,Chinese Academy of sciences,Beijing 100101,china 2 Beijing National Laboratory for molecular sciences(BNLMS),Centre for molecular sciences,institute of Chemistry,Chinese Academy of sciences,Beijing 100080,china 3 Beijing Entry-Exit Inspection and Quarantine,Beijing 100026,china 1. institute of Biophysics Chinese Academy of Sciences Beijing 100101 China 2. Beijing National Laboratory for molecular sciences (BNLMS) Centre for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 3. Beijing Entry-Exit Inspection and Quarantine Beijing 100026 China

In polymerization of N-carboxyanhydride-L-α-arginine(L-Arg-NCA) in H2O,nucleophilic reaction of guanidine group with the carbonyl group of L-Arg-NCA leads to quick intramolecular rearrangement,yielding a 6-membered ring intermediate 1-amidino-3-amino-2-piperidone,which is either elongated by another L-Arg-NCA yielding arginyl-1-amidino-3-amino-2-piperidone or hydrolyzed to L-α-*** oligoarginines are formed mainly through hydrolysis of *** is a unique pathway in polymerization of L-Arg-NCA with regard to the usual pathway of elongations by reaction of N-carboxyanhydride-L-α-amino acid with L-α-amino acid or oligopeptides.

关键词： N-carboxyanhydride L-Arg-NCA intermediates L-α-arginine polymerization

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 Chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

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

Electronic structure and magnetism of R(Fe,Si)_(12) (R=Y,Nd)

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2, FAN Zhijian1, GAO Tao3 & QI Xinhua31. institute of Nuclear Physics and Chemistry, china Academy of Engineering Physics, Mianyang 621900, china 2. Department of physics, Peking university, Beijing 100871, china 3. institute of atomic and molecular Physics, Sichuan University, Chengdu 610065, china 1. institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. Department of physics Peking university Beijing 100871 China 3. institute of atomic and molecular Physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

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) ACAD sinica INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA china INST ATOM ENERGY BEIJING 102413PEOPLES R CHINA

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

EVOLUTION CHARACTERISTICS IN PLASMA-SHEATH WITH PERIODICALLY FORCED OSCILLATION

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Science in china,Ser.A 1986年第8期29卷 835-846页

作者：方锦清周刘来 institute of atomic Energy. academia sinica Beijing

This paper considers plasma-sheath physical model with a periodically forced oscillation. The numerical study on the equation of the plasma-sheath has been carried out with a few methods. It has been found that the three well-known transition routes to chaos coexist in the model as the control parameters are varied separately. We make a discussion on the relation between the results and physical process and point out that this intrinsic stochastlcs is a prineipal origin leading to the plasma instability in some plasma devices(e.g. plasma ion sources, electromagnetic isotope separator and so on).

关键词： EVOLUTION CHARACTERISTICS IN PLASMA-SHEATH WITH PERIODICALLY FORCED OSCILLATION mode As Hopf