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Science china chemistry 2007年第5期50卷 629-637页

作者： LIU JiangTao1,2, LIU ZhongFang1 & LIU ShaoPu1 1 School of chemistry and Chemical Engineering, Southwest university, chongqing 400715, china 2.department of chemistry, fuling normal university, chongqing 408000, china School of chemistry and Chemical Engineering Southwest UniversityChongqing400715China department of chemistry Fuling Normal UniversityChongqing 408000China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2 buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 301 nm for ctDNA and sDNA,370nm for hsDNA,310 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3 sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2 ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2 & TIAN Anmin2 1. department of chemistry, Southwest-china normal university, chongqing 400715, china 2. department of chemistry, Sichuan university, Chengdu 610064, china 1. department of chemistry Southwest-China Normal University Chongqing 400715 China 2. department of chemistry Sichuan University Chengdu 610064 China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

Progress in the study of molecular organized assemblies by dielectric relaxation spectroscopy

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Progress in Natural Science:Materials International 2006年第3期16卷 221-230页

作者： ZHAO Kongshuang, HE Kejuan and WEI Suxiang (department of chemistry, Beijing normal university, Beijing 100875, china department of chemistry, South china normal university, Guangzhou 510631, china) [a]department of chemistry Beijing Normal University Beijing China [b]department of chemistry South China Normal University Guangzhou China

Because dielectric spectroscopy covers a great many problems in physical and chemical systems occurring in an extremely wide frequency range, the study of this method plays an important role in physical chemistry. As an effective tool to detect inner properties of substance systems, the dielectric spectroscopy method is widely used in chemical systems and has been dramatically developed in recent decade. This review paper describes the applications of the dielectric spectroscopy in the chemical field, and main concentrations are focused on the micelle, microemulsion and other so-called molecular organized assemblies. Some dielectric principles and models proposed for these systems are introduced. In addition, recent technical developments in dielectric spectroscopy and developing trend of this method in other chemical systems are reviewed.

关键词： dielectric relaxation micelle microemulsion vesicle relaxation time.

Synthesis and Crystal Structure of CoCl(ieaa)(C_(10)H_7-ieai)(C_(10)H_7NH_2)

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Chinese Journal of Structural chemistry 2002年第1期21卷 22-25页

作者： FENG Yun-Long (department of chemistry, Zhejiang normal university Jinhua 231004,china) department of chemistry Zhejiang Normal University Jinhua 231004

The title complex CoCl(ieaa)(C10H7-ieai)(C10H7NH2), C32H32ClCoN4O7, Mr= 679.00; (ieaa- and C10H7-ieai- are the anions of isonitrosoethylacetoacetate and its N-a- naphthylamine derivative of Schiff base, respectively, C10H7NH2 is a-naphthylamine), crystallizes in the monoclinic system, space group P21/n with a=11.846(2), b=23.912(5), c=12.783(3)? b=116.54(3), V=3239(1)?, Dc=1.392g/cm3, F(000)=1408, Mr=679.00, m(MoKa)=0.665mm-1, Z=4, final R=0.0584 and wR=0.1388 for 4177 observed reflections (I ≥ 2s(I)). A nitrogen atom of the ieaa- ligand and two nitrogen atoms of the C10H7-ieai- ligand define one of the triangular faces in the distorted octahedral geometry about the cobalt atom. The title complex contains isonitroso-b-ketoimine.

关键词： cobalt complex isonitroso-b-ketoimine Schiff base crystal structure

Preparation of insoluble β-CD polymer and its application to enantiomers and isomers separation

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Journal of Central South university of Technology 2001年第1期8卷 57-59页

作者： YI Jian ming 1,TANG Kuo wen 2 (1.College of chemistry and Chemical Engineering, Central South university, Changsha 410083, china 2.department of Chemical Engineering, Yueyang normal university, Yueyang 414000, china) 1. College of chemistry and Chemical Engineering Central South University 410083 Changsha China 2. department of Chemical Engineering Yueyang Normal University 414000 Yueyang China

An insoluble β-cyclodextrin polymer cross-linked with epichlorohydrin was prepared, and its structure was identified with infrared spectrum. Colloid stationary phase was prepared by dissolving the polymer in the mixed solvent of diisopropyl ether, methylene dichloride and benzene and treated for 0.5 h by ultrasonication, and then was coated on a fused silica capillary column. The optimun reaction conditions are as follows: the mole ratio of epichlohydrin to β-cyclodextrin is 12.1:1, reacting at 65 °C for 24 h. The Chromatographic performance such as column efficiency, thermal stabilities and polarity were studied, two kinds of disubstituted benzene isomers and eight pairs of enantiomers were separated on the capillary column. The results show that the β-cyclodextrin polymer is suitable for use as a capillary gas chromatographic stationary phase, and possess excellent chromatographic properties in separating enantiomers and position isomers.

关键词： insoluble β cyclodextrin polymer capillary gas chromatography enantiomer position isomer separation

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science china chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2, ZHAO Hongmei1 & LI Zonghe1 1. department of chemistry, Beijing normal university, Beijing 100875, china 2. department of chemistry, Qujing normal College, Qujing 655000, china 1. department of chemistry Beijing Normal University 100875 Beijing China 2. department of chemistry Qujing Normal College 655000 Qujing China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3LYP/6-311G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2(CN)C─ N=N─ C(CN)Me2? 2Me2(CN)C?+N2 is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2(CN)CN=N─C(CN)Me2 ? Me2(CN)CN=N?+ Me2(CN)C?? Me2(CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2(CN)C?radical as well as N2 molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

On the generalized Busemann-Petty problem

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Science china Mathematics 2007年第8期50卷 1103-1116页

作者： Song-jun L~(1,2+) Gang-song LENG~1 1.College of Mathematics and Computer Science,chongqing normal university,Chongqin 400047,china 2.department of Mathematics,Shanghai university,Shanghai 200444,china College of Mathematics Computer Science Chongqing Normal University Chongqin 400047 China department of Mathematics Shanghai University Shanghai 200444 China

The generalized Busemann-Petty problem asks whether the origin-symmetric convex bodies in ? n with a larger volume of all i-dimensional sections necessarily have a larger volume. As proved by Bourgain and Zhang, the answer to this question is negative if i > 3. The problem is still open for i = 2, 3. In this article we prove two specific affirmative answers to the generalized Busemann-Petty problem if the body with a smaller i-dimensional volume belongs to given classes. Our results generalize Zhang’s specific affirmative answer to the generalized Busemann-Petty problem.

关键词： star body cross i-section dual mixed volume Radon transform 52A30 52A40

A note on the crossed product R(A, α) associated with PSL_2(R)

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Science china Mathematics 2008年第11期51卷 2081-2088页

作者： WU WenMing 1 School of Mathematical and Computer Science, chongqing normal university, chongqing 400047, china 2.department of Mathematical Science, Tsinghua university, Beijing 100084, china School of Mathematical and Computer Science Chongqing Normal University Chongqing China department of Mathematical Science Tsinghua University Beijing China

Given the hyperbolic measure dxdy/y2 on the upper half plane H, the rational actions of PSL2(R) on H induces a continuous unitary representation α of this group on the Hilbert space L2(H, dxdy/y2). Supposing that A = {Mf : f ∈ L∞(H, dxdy/y2)}, we show that the crossed product R(A,α) is of type I. In fact, the crossed product R(A,α) is *-isomorphic to the von Neumann algebra B(L2(P,ν))■LK, where LK is the abelian group von Neumann algebra generated by the left regular representation of K.

关键词： crossed product rational actions PSL2(R) von Neumann algebras

A local spin evaluation into the active site models of [2Fe2S] ferrodoxin [Fe_2S_2(SR)_4]^(2-) (R=-H, -CH_3)

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Science china chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2, WANG Yan3 & JU GuanZhi2,3 1 department of chemistry, Hainan normal university, Haikou 571158, china 2 State Key Laboratory of Theoretical and Computational chemistry, Jilin university, Changchun 130023, china 3 department of chemistry, Nanjing university, Nanjing 210093, china 1. department of chemistry Hainan Normal University Haikou 571158 China 2. State Key Laboratory of Theoretical and Computational chemistry Jilin University Changchun 130023 China 3. department of chemistry Nanjing University Nanjing 210093 China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2S2(SR)4]2- (R=-H, -CH3) are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , 2 >, and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

Mixed-valence copper coordination polymers based on CuSCN or CuN_(3) as bridging motifs

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Science china chemistry 2005年第z1期48卷 41-44页

作者： FAN Guang,GAO Shengli,CHEN Sanping,ZENG Minghua & XIE Gang department of chemistry,Northwest university,Xi’an 710069,china department of chemistry,Guangxi normal university,Guilin 541000,china NW Univ Xian Dept Chem Xian 710069 Peoples R China Guangxi normal Univ Dept Chem Guilin 541000 Peoples R China

Two novel mixed valence copper coordination polymers, [Cu(2-pac)2(CuN3)(H2O)]n (1) and [Cu(2-pac)2(CuSCN)2]n (2), have been prepared through hydrothermal synthesis and analyzed for structure determination, which exhibit two- and three-dimensional structures respectively. In complex (1), zigzag chains of [CuN3]n running parallel to the c direction are interconnected by Cu(2pac)2 to form a two-dimensional layer structure. In complex (2), the arrangement of μ-1,1,3 bridging thiocyanate ligand leads to the formation of ten-membered Cu-SCN- Cu-S-Cu-NCS rings, and each Cu atom is further linked by Cu(2-pac)2 to afford a three-dimensional configuration.

关键词： hydrothermal synthesis, crystal structure, 2-pyrazinecarboxylic acid, coordination polymer.