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Changes of decay rates of radioactive ^(111)In and ^(32.P induced by mechanic motion

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science China chemistry 2007年第2期50卷 170-174页

作者： HE YuJian1,QI Fei2.& QI shengChu3 1 College of chemistry and chemical {2.,Graduate university of Chinese Academy of sciences,Beijing 100049,China 2.No. 1,Gravenhurst Court,Gaithersburg,Md 2.878,UsA 3 department of Applied chemistry,Peking university,Beijing 100871,China 1. College of chemistry and chemical {2. Graduate University of Chinese Academy of Sciences Beijing 100049 China 2. No. 1 Gravenhurst Court Gaithersburg Md 20878 USA 3. department of Applied chemistry Peking University Beijing 100871 China

The changes of decay rates of radionuclide 111In(electron capture) and 32.(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2.00 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32. compared with the referred(14.2. d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32. is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32. return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32.,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

关键词： circular rotation helical motion 111In 32. decay rate chirality

synthesis,characterization,structures and magnetic property of chiral oxalate-bridged dicopper(Ⅱ) complexes

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science China chemistry 2010年第6期53卷 1255-1260页

作者： WU Ling1,WANG Jun2.ZHU CaiFei1,LIN YiJi1,CHEN LeiQi1,FAN Jun2.& ZHANG Hui1 1state Key Laboratory of Physical chemistry of solid surfaces department of chemistry,College of chemistry and chemical engineering,Xiamen university,Xiamen 361005,China 2.chool of chemistry and Environment,south China Normal university,Guangzhou 510006,China 1. state Key Laboratory of Physical chemistry of solid surfaces department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Environment South China Normal University Guangzhou 510006 China

The oxalato-bridged dicopper(II) complexes [Cu2.μ-ox)(LRR)2.H2.)2.ClO4)2. (1),[Cu2.μ-ox)(LRR)2.CH3COCH3)2.ClO4)2.(1a),[Cu2.μ-ox)(Lss)2.H2.)2.ClO4)2. (2. and [Cu2.μ-ox)(LRR)(Lss)2.CH3COCH3)2.ClO4)2. (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2.2.-bipyridine,Lss = (8s,10s)-(+)-[4,5]-pineno-2.2.-bipyridine;ox2. oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was *** on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2.were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same *** crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear *** solution CD spectra of 1 and 2.in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and Lss,*** 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers *** exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.

关键词： dicopper(II) complex chiral bipyridine μ-oxalate bridge crystal structure CD spectroscopy magnetic property

Water gas shift activity of Co-Mo/MgO-Al_2._3 catalysts presulfided with ammonium sulfide

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Journal of Natural Gas chemistry 2010年第1期19卷 61-66页

作者： Yixin Lian, Huifang Wang, Weiping Fang, Yiquan Yang department of chemistry, College of chemistry and chemical engineering, National engineering Laboratory for Green chemical Productions of Alcohols, Ethers and Esters, Xiamen university, Xiamen 361005, Fujian, China [a] department of chemistry College of Chemistry and Chemical Engineering National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 Fujian China

Co-Mo/MgO-Al2.3 catalyst was presulfided with ammonium sulfide in aqueous solution and activated with synthesis gas for water gas shift reaction. The assay results indicate that the presulfided Co-Mo/MgO-Al2.3 catalyst exhibits an excellent catalytic activity and stability. XRD and EPR characterization results show that the O-s exchange might occur during the impregnation, leading to the formation of （NH4）2.os4 （or （NH4）zMoxsy） precursor, which was then thermally decomposed and reduced to Mos2. The higher catalytic performance is attributed to an optimization formation of active Co-Mo sulfides, consisting of well dispersed Mos2.and Co-Mo-s phase due to the redispersion of Co sulfide particles over the edges of newly formed Mos2.crystallites.

关键词： Co-Mo-based catalyst ammonium sulfide presulfidation water-gas shift

synthesis and structural Characterization of [(h^5-C_5Me_5)_2.o_2.e_2._4Br_2.

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Chinese Journal of structural chemistry 2002年第1期21卷 34-37页

作者： YU Hong JI shun-Jun Lang Jian-Ping② (department of chemistry and {2. engineering, suzhou university, suzhou 2.5006, China) department of chemistry and {2. engineering Suzhou University Suzhou 215006

The reactions of [(h5-C5Me5)Mo(stBu)3] with equimolar FeBr3 in THF afforded a neutral tetranuclear cluster [(h5-C5Me5)2.o2.e2.4Br2. 1. The structure of 1 was determined by single-crystal X-ray diffraction analysis. 1 crystallizes in the monoclinic space group P2./n (No. 14) with a = 9.691(2., b = 15.2.4(2., c = 18.850(2. ? b = 96.44(1), V = 2.59.8(7) ?, Z = 4, Mr = 862.08, Dc = 2.075 g/cm3, F(000) = 1680, m (MoKa) = 51.31 cm-1 and T = 2.6.2.K. With the use of 3667 observed reflections (I > 3.0s(I)), the structure was refined to R = 0.041 and Rw = 0.051. 1 is composed of a distorted Mo2.e2.4 cubane core with two Br atoms and two h5-C5Me5 groups coordinating at the Fe and Mo sites, respectively. The lengths of MoMo and FeFe bonds are 2.82. and 2.773 ? respectively the mean length of MoFe bond is 2.751 ?

关键词： synthesis crystal structure molybdenum cluster iron cluster

standard Enthalpy of Formation of Monoclinic Ammonium Paratungstate

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Chinese chemical Letters 1999年第12期10卷 0-0页

作者： shi Jun LIU Qi Yuan CHEN Ping Min ZHANG(1department of chemistry, Xiangtan {2., Xiangtan 411105)(2.0} of chemistry, Central south {2. of Technology, Changsha 410083) Xiangtan Univ Dept Chem Xiangtan 411105 Peoples R China Cent s Univ Technol Dept Chem Changsha 410083 Peoples R China

The enthalpy of reaction for the decomposition of monoclinic ammonium paratungstate,(NH_4 )_10 H_2. W_12.O_42.H_2.O(s), was measured using a HT-1000 calorimeter. From the experimentalresults, the standard enthalpy of ... 详细信息

关键词： standard enthalpy of formation monoclinic ammonium paratlingstate calorimetry.

Theoretical study on s_1(~1B_(3u)) state electronic structure and absorption spectrum of pyrazine

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science China chemistry 2008年第12期51卷 1166-1173页

作者： HE RongXing1, ZHU ChaoYuan 2. CHIN Chih-Hao3 & LIN sheng-Hsien2.3 1 College of chemistry and chemical {2., southwest university, Chongqing 400715, China 2.department of Applied chemistry, Institute of Molecular science and Center for Interdisciplinary Molecular science, National Chiao-Tung university, Hsinchu 300, China 3 Institute of Atomic and Molecular sciences, Academia sinica, Taipei 106, China 1. College of chemistry and chemical {2. Southwest University Chongqing 400715 China 2. department of Applied chemistry Institute of Molecular Science and Center for Interdisciplinary Molecular Science National Chiao-Tung University Hsinchu 300 China 3. Institute of Atomic and Molecular sciences Academia Sinica Taipei 106 China

Making use of a set of quantum chemistry methods, the harmonic potential surfaces of the ground state (s0(1Ag)) and the first (s1(1B3u)) excited state of pyrazine are investigated, and the electronic structures of the two states are characterized. In the present study, the conventional quantum mechanical method, taking account of the Born-Oppenheimer adiabatic approximation, is adopted to simulate the absorp-tion spectrum of s1(1B3u) state of pyrazine. The assignment of main vibronic transitions is made for s1(1B3u) state. It is found that the spectral profile is mainly described by the Franck-Condon progression of totally symmetric mode ν6a. For the five totally symmetric modes, the present calculations show that the frequency differences between the ground and the s1(1B3u) state are small. Therefore the displaced harmonic oscillator approximation along with Franck-Condon transition is used to simulate s1(1B3u) absorption spectra. The distortion effect due to the so-called quadratic coupling is demonstrated to be unimportant for the absorption spectrum, except the coupling mode ν10a. The calculated s1(1B3u) ab-sorption spectrum is in reasonable agreement with the experimental spectra.

关键词： pyrazine absorption spectrum quantum mechanical method electronic structure

Electrochemical performance of LiFePO_4 cathode material for Li-ion battery

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Rare Metals 2006年第z1期25卷 62-66页

作者： LI shuzhong LI Chao FAN Yanliang XU Jiaqiang WANG Tao YANG shuting engineering Research Centre for New Power source Materials of Henan Province Xinxiang 453002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China department of Applied chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Department of Chemical Engineering College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China

In the search for improved materials for rechargeable lithium batteries, LiFePO4 offers interesting possibilities because of its low raw materials cost, environmental friendliness and safety. The main drawback with using the material is its poor electronic conductivity and this limitation has to be overcome. Here Al-doped LiFePO4/C composite cathode materials were prepared by a polymer-network synthesis technique. Testing of X-ray diffraction, charge-discharge, and cyclic voltammetry were carried out for its performance. Results show that Al-doped LiFePO4/C composite cathode materials have a high initial capacity, good cycle stability and excellent low temperature performance. The electrical conductivity of LiFePO4 material can be obviously improved by doping Al. The better electrochemical performances of Al-doped LiFePO4/C composite cathode materials have a connection with its conductivity.

关键词： lithium ion batteries LiFePO4 doping electrochemical performance

Two-dimensional investigation of forced bubble oscillation under microgravity

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Progress in Natural science:Materials International 2003年第12期 9-14页

作者： HONG Ruoyu 1 and Masahiro KAWAJI 2.1. department of chemistry and {2. engineering, soochow university, suzhou 2.5006, China 2. department of {2. engineering and Applied chemistry, university of Toronto, Toronto ON M5s 3E5, Canada) department of chemistry and {2. engineering Soochow University Suzhou 215006 China department of chemical {2. and Applied chemistry University of Toronto Toronto ON M5S 3E5 Canada

Recent referential studies of fluid interfaces subjected to small vibration under microgravity conditions are reviewed. An experimental investigation was carried out aboard the American space shuttle Discovery . Two dimensional (2. D) modeling and simulation were conducted to further understand the experimental results. The oscillation of a bubble in fluid under surface tension is governed by the incompressible Navier stokes equations. The sIMPLEC algorithm was used to solve the partial differential equations on an Eulerian mesh in a 2. D coordinate. Free surfaces were represented with the volume of fluid (VOF) obtained by solving a kinematic equation. surface tension was modeled via a continuous surface force (CsF) algorithm that ensures robustness and accuracy. A new surface reconstruction scheme, alternative phase integration (API) scheme, was adopted to solve the kinematic equation, and was compared with referential schemes. Numerical computations were conducted to simulate the transient behavior of an oscillating gas bubble in mineral oil under different conditions. The bubble positions and shapes under different external vibrations were obtained numerically. The computed bubble oscillation amplitudes were compared with experimental data.

关键词： Navier stokes (N s) equations volume of fluid (VOF) microgravity bubble oscillation.

Adsorptive desulfurization on a heteroatoms Y zeolite prepared by secondary synthesis

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science China chemistry 2010年第1期53卷 281-286页

作者： TANG Ke1,HONG Xin1,ZHAO YongHua1,sONG LiJuan2.& sUN ZhaoLin2.1school of Material and chemical engineering,Liaoning Institute of Technology,Jinzhou 12.001,China 2.ollege of Petrochemical engineering,Liaoning university of Petroleum & chemical Technology,Fushun 113001,China 1. school of Material and chemical engineering Liaoning Institute of Technology Jinzhou 121001 China2. College of Petrochemical Engineering Liaoning University of Petroleum & Chemical Technology Fushun 113001 China

Gallium atoms have been introduced into the framework of Y zeolite by treating the zeolite with an aqueous solution of ammonium hexafluoro *** of various model fuels containing about 500 μg/g sulfur has been studied over the synthesized Y zeolite(GaAlY).The sulfur adsorption capacity is 7.0,17.4,14.5,16.9,6.9 and 5.8 mg(s)/g adsorbent for thiophene,tetrahydrothiophene(THT),4,6-dimethyldibenzothiophene(4,6-DMDBT),dibenzophiophene(DBT),benzothiophene(BT) and 4-methyldibenzothiophene(4-MDBT),*** charges on the s atom in thiophene,THT,4,6DMDBT,DBT,BT and 4-MDBT,calculated using the density functional theory(DFT),are-0.159,-0.2.8,-0.2.4,-0.2.1,-0.193 and-0.188,respectively,implying that the s-M bond between the adsorption sites and thiophene is much weaker than that between the adsorption sites and THT,4,6-DMDBT or *** sulfur removal of FCC gasoline on GaAlY is 68%.

关键词： isomorphous substitution DFT model fuels adsorptive desulfurization