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Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2.& JIANG Zonglin2.1. Key laboratory of High Temperature Gas dynamics, Institute of Mechanics, {2. academy of Sci- ences, beijing 100080, china 2. Graduate University of chinese academy of sciences, beijing 100039, china Key laboratory of High Temperature Gas dynamics Institute of Mechanics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

High-resolution photofragment translational spectro- scopy for the UV photodissociation of C_2._5I

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Science china chemistry 2007年第4期50卷 476-482页

作者： BI WeiBin, XU XiLing, HUANG JianGou, XIAO DaoQing & ZHU QiHe beijing National laboratory for {2. sciences, State Key laboratory of {2. reaction dynamics, Institute of chemistry, chinese academy of sciences, beijing 100080, china beijing National laboratory for {2. sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The photodissociation of ethyl iodide at 2.9.71, 2.1.73, 304.02.and 304.67 nm has been studied on our new mini-photofragment translational spectrometer with a total flight path of only 5 cm. Some vibra-tional peaks are firstly resolved in the TOF spectra of I*(2.1/2. and I(2.3/2. channels. These vibrational peaks are assigned to the excitation states (ν2.= 0, 1, 2.…) of the umbrella mode (ν2. 540 cm-1) of the photofragment C2.5, and the distribution of the vibrational states is obtained. The dissociation energy has been determined to be D0(C-I)=2.314 ± 0.03 eV. The energy partitioning of the available energy (Eavl=ET+Eint=ET+EV,R) calculated from our experimental data E int /E avl= 2..1% at 2.1.73 nm, 2..4% at 304.02.nm for the I* channel, and E int /E avl= 2..2. at 2.9.71 nm, 2..9% at 304.67 nm for the I channel, seem to be more reliable.

关键词： photofragment translational spectroscopy C_2._5I photodissociation vibrational state distribution energy partitioning dissociation energy

Study on the atmospheric photochemical reaction of CF_3 radicals using ultraviolet photoelectron and photoionization mass spectrometer

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Science china chemistry 2008年第4期51卷 316-321页

作者： YAO Li1,2. DU Lin1,2. YIN Shi1,2.& GE MaoFa1 1 beijing National laboratory for {2. sciences (BNLMS), State Key laboratory for Structural chemistry of Unstable and Stable Species, Institute of chemistry, chinese academy of sciences, beijing 100080, china 2.Graduate University of chinese academy of sciences, beijing 100080, china beijing National laboratory for {2. sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2.was performed by using a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PES- PIMS). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investigated. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxygen and a fluo- rine lone pair of CF3 group. The outermost electrons reside in the oxygen lone pair. The experimental and theoretical first vertical ionization energy is 13.2. and 13.178 eV, respectively, with the PES and OVGF method. They are in good agreement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PES-PIMS experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and giving the fragments CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- plied widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species

Microdynamics study on reaction of atom H and radical NH(X^3Σ)

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chinese Science Bulletin 1999年第11期44卷 1000-1003页

作者： XU Lijin, YAN Jimin and KONG Fan’aoState Key laboratory of molecular {2. dynamics , Institute of chemistry, chinese academy of sciences , beijing 100080, china Corresponding author State Key laboratory of Moleclar reaction {2. Institute of Chemistry Chinese Academy of Sciences Beijing China

The dynamics of the H + NH→N + H2.reaction has been investigated by means of the 3-atom model quasiclassical trajectory approach. The LEPS potential energy surface is employed in the study, which is obtained from the... 详细信息

The dynamics of the H + NH→N + H2./sub> reaction has been investigated by means of the 3-atom model quasiclassical trajectory approach. The LEPS potential energy surface is employed in the study, which is obtained from the ab initio results and has an early saddle point in the minimum energy path. The results indicate that the reaction product H2./sub> is mainly scattered backward,and the reaction is found to occur via a direct channel. The product H2./sub> is in a cold excitation of rotational state, but has a hot vibrational excitation. Based on the potential surface and the trajectory analysis, the reaction mechanism has been explained successfully.

关键词： microdynamics of reaction quasiclassical trajectory calculation LEPS potential energy surface direct reaction.

Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

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Science china chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2.3, SUN Chengke1,4, ZHANG Rongchang3, XI Hongmin3 & LI Zonghe1 1. Department of chemistry, beijing Normal University, beijing 100875, china 2. the laboratory of molecular reaction dynamics, Institute of chemistry, chinese academy of sciences, beijing 100080, china 3. Department of chemistry, Beihua University, Jilin 132.13, china 4. Department of chemistry, Qujing Normal University, Yunnan 655000, china Department of chemistry Beijing Normal University Beijing China The laboratory of molecular {2. dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China Department of chemistry Beihua University Jilin China Department of chemistry Qujing Normal University Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

A Detailed dynamics Study of the reaction CH_4+Cl→HCl+CH_3

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chinese Chemical Letters 1998年第8期9卷 771-774页

作者： Li Jin XU Xue Bin WANG Ji Min YAN Fan Ao KONG (State Key laboratory of molecular {2. dynamics, Institute of chemistry,chinese academy of sciences, beijing 100080) State Key Lab. Molec. reaction D. Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The detailed dynamics of the CH4+Cl→HCl+CH3 reaction has been investigated by means of the quasiclassical trajectory approach. The properties analyzed can be interpreted in terms of the main topological featUres of the potential energy surface used. on the basis of the theoretical results, two reaction channels are proposed: one is a direct channel and the other is a complex one.

关键词： quasiclassical trajectory calculation LEPS potential energy surface

molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1,2., GUO Qionglin~1**, HU Wei~1, WANG Yaping~1 and ZHU Zuoyan~1(1. State Key laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072.{2. 2. Graduate School of chinese academy of sciences, beijing 100039,{2.) State Key laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1806 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 32. bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 32. bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science china chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2. WANG Jin3, WU Yishi1, YUAN Gu3, AI Xicheng1, WANG Li4 & ZHANG Jianping1 1. State Key laboratory for Structural chemistry of Unstable and Stable Species, Institute of chemistry, chinese academy of sciences, beijing 100080, china 2. School of Life Science and Technology, beijing Institute of Technology, beijing 100081, china 3. College of chemistry and molecular Engineering, Peking University, beijing 100080, china 4. Center for Condensed Matter Physics, Institute of Physics, chinese academy of sciences, beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping State Key laboratory for Structural chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China School of Life Science and Technology Beijing Institute of Technology Beijing China College of chemistry and molecular Engineering Peking University Beijing China Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32.ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

POLYMERIZATION OF ETHYLENE WITH UNSYMMETRIC 2.6-BIS(IMINO)PYRIDINE IRON(Ⅱ)COMPLEX

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chinese Journal of Polymer Science 2002年第3期20卷 205-211页

作者： Zhi Ma Wen-hua Sun Zi-long Li Chang-xing Shao You-liang Hu State Key laboratory of Engineering Plastics and the Center for molecular {2. Institute of chemistry chinese academy of sciences, beijing 100080 china State Key Lab. of Engineering Plast. Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

An unsymmetric 2.6-bis(imino)pyridine iron(II) complex 1' was synthesized. The relationship between catalyststructure and its activity in ethylene polymerization is discussed. The kinetic behavior of ethylene polymerization and theeffects of polymerization conditions such as temperature, aluminum/iron molar ratio on the activity of catalyst and thecharacteristics of polyethylene were reported. The unsymmetric catalyst 1' has a good catalytic performance of 3.47×10~6 gPE·mol^(-1)·Fe·h^(-1) at 40℃ with aluminum/iron molar ratio = 2.00. A dependence of catalyst activity on themethylaluminoxane (MAO) concentration and reaction temperature was found. The molecular weight (MW) of polyethylenewith broad dispersity is about 10~4-10~5 g/mol. The melting temperature and branching of polyethylenes vary with changingreaction temperature and aluminum/iron molar ratio.

关键词： Unsymmetric 2.6-bis(imino)pyridine iron(Ⅱ) complex Ethylene polymerization Catalyst structure Catalytic activity