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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 {3., Beijing 100875, China 2. department of chemistry, qujing normal College, qujing 655000, China Dept. of Chem. Beijing Normal Univ. Beijing 100875 China Dept. of Chem. Qujing Normal Coll. Qujing 655000 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 B3.YP/6-3.1G* 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).

The Nature of Bonding in IrC

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Chinese Chemical Letters 1998年第12期9卷 0-0,0-0页

作者： Xiao Guang XIE Huai CAO (Modem Biological Center, yunnan university, Kunming 650091)Xian Jun BI (department of {3., yunnan normal university, Kunming 650092)Shu Shan Dai (department of {3., yunnan university, Kunndng 650091) Modern Biological Center Yunnan University Kunming 650091 China department of chemistry Yunnan Normal University Kunming 650092 China department of chemistry Yunnan University Kunming 650091 China

The nature of bonding in the title compound has been stUdied by using CASSCF andFOCI techniques. The ground state of IrC has been found to be 2△ arising primarilyfrom:.. 1σ2 2σ2 1π4.1δ3.3.2 configuration, which forms a triple bond between Ir and C atoms (one σ;two π). The lowest quartet state is 4. state which has the configuration:... 1σ2 2σ2 1π4.1δ3.2π1 3.2 andlies higher than the ground state by 1 .25eV. The molecular constants of the ground state calculatedat CASSCF level by using Morse's mode are: Re=1.6904., De=4.86eV, We=113.cm-1, andB0=0.5219cm-1 comparable with the spectrum values (Re=1 .6858A, De=6.4. eV, We=1051cm-1and B0=0.5251 cm-1).

关键词： Nature of bonding IrC molecular constants CASSCF

The Nature of Bonding in PtN

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Chinese Chemical Letters 1998年第7期9卷 687-690页

作者： Xiao Guang XIE Xian Jun BI Huai CAO Shu Shan DAI (Modem Biological Center, yunnan university, Kunming 650091)(department of {3., yunnan normal university, Kunming 650092)(department of {3., yunnan university, Kunming 650091) Modern Biological Center Yunnan University Kunming 650091 China department of chemistry Yunnan Normal University Kunming 650092 China department of chemistry Yunnan University Kunming 650091 China

The nature of bonding in the title compound has been studed by using CASSCF techniques. The ground state of PtN is found to be (2)Pi state arising primarily from: 1 sigma(2)2 sigma(2)1 pi(4.1 delta(4.3.sigma(2)2 pi(1) configuration, which forms triple bond between Pt and N atoms tone sigma, two pi). The lowest quartet state is (4.Sigma(-) State which has the configuration: ...1 sigma(2)2 sigma(2)1 pi(4.1 delta(4.3.sigma(1)2 pi(2) and lies higher than the ground state by 0.4.eV.

关键词： PtN nature of bonding molcular constants CASSCF

Ab Initio Study of the Excited State Decomposition Reactions of Monothioformic Acid

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Chinese Chemical Letters 1998年第5期9卷 459-461页

作者： Xiao Guang XIE Huai CAO (Modem Biological Center, yunnan university Kunndng 650091)Xian Jun BI (department of {3., yunnan normal university Kunming 650092)Shu Shan DAI (department of {3., yunnan university Kunndng 650091) Modern Biological Center Yunnan University Kunming 650091 China department of chemistry Yunnan Normal University Kunming 650092 China department of chemistry Yunnan University Kunming 650091 China

The possible excited state decomposition reactions (dehydrogensulfidation, dehydration, and dehydrogenation) of the four tautomers of monothioformic acid have been investigated by ab initio methods with 6-3.G** basis sets at the CIS level. The activation energies of the four excited state reactions are 4..57, 4..4., 56.90, 4..73.kcal/mol, and are respectively lower than that of the ground states by 24.52, 24.98, 27.28, and 21.10 kcal/mol.

关键词： monothioformic acid excited state decomposition reaction ab initio

Kinetic model of transesterification of diphenyl carbonate and 1,4.butyldiol

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Journal of Natural Gas chemistry 2010年第4期19卷 436-440页

作者： Liping Wang1,2,3.4.Bin Xiao1,2,4.Gongying Wang1,2 1.Chengdu Institute of Organic chemistry,Chinese Academy of Science,Chengdu 61004.,Sichuan,China 2.Changzhou Key Laboratory of Green and Technology,Changzhou Institute of chemistry,Changzhou 213.64.Jiangsu,China 3.department of chemistry,{4. normal College,{4. 655000,yunnan,China 4.Graduate School of Chinese Academy of Science,Beijing 10003.,China Chengdu Institute of Organic chemistry Chinese Academy of Science Chengdu 610041 Sichuan China Changzhou Key Laboratory of Green and Technology Changzhou Institute of Chemistry Changzhou 213164 Jiangsu China department of chemistry Qujing Normal College Qujing 655000 Yunnan China Graduate School of Chinese Academy of Science Beijing 100039 China

The transesterification of diphenyl carbonate （DPC） with 1,4.butyldiol （BD） was kinetically investigated in the presence of lithium acetate catalyst at 4.5 *** reaction was followed by the measurement of the quantity of phenol which was distilled from the *** experiments supported the assumption that the phenyl ester groups in DPC and phenyl hdroxybutyl carbonate （PHBH） had the same reactivity,and the transesterification obeyed first-order kinetics with respect to DPC and BD,and a rate equation was *** reaction rate was found to be first order with respect to the catalyst concentration as *** those data were incorporated in the rate equation,excellent agreement between calculated values and the observed ones was recognized over a wide range.

关键词： transesterification diphenyl carbonate 1,4.butyldiol lithium acetate kinetics

Microwave Effect On Partial Oxidation of Methane to Syngasover Ni/ZrO_2

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Chinese Chemical Letters 1998年第8期9卷 775-777页

作者： Xian Jun BI Xiao Guang XIE Ai Hong DUAN Pin Jie HONG Shu Shan DAI(department of chemistry, yunnan {3. {4., Kunming 650092)(department of chemistry, yunnan {4., Kunming 650091) department of chemistry Yunnan Normal University Kunming 650092 China department of chemistry Yunnan University Kunming 650091 China

The partial oxidation of methane to syngas over Ni/ZrO2 catalyst irradiated by ndcrowave has been studied. Compared with a conventional heating mode, the temperature of the catalytic bed is much lower and there is a h... 详细信息

关键词： microwave partial Oxidation methane syngas Ni/ZrO_2

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 {3. Jinhua 23.004.China) department of chemistry Zhejiang Normal University Jinhua 231004

The title complex CoCl(ieaa)(C10H7-ieai)(C10H7NH2), C3.H3.ClCoN4.7, 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=11.84.(2), b=23.912(5), c=12.783.3.? b=116.54.3., V=3.3.(1)?, Dc=1.3.2g/cm3. F(000)=14.8, Mr=679.00, m(MoKa)=0.665mm-1, Z=4. final R=0.0584.and wR=0.13.8 for 4.77 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

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 {3., Beijing 100875, China department of chemistry, South China normal {3., Guangzhou 51063., China) department of chemistry Beijing Normal University Beijing 100875 China department of chemistry South China Normal University Guangzhou 510631 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.

ADSORPTION OF GALLIUM WITH N_503.EVEXTREL RESIN

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中国有色金属学会会刊：英文版 1994年第3期4卷 36-40页

作者： Chen, Jianrong Hu, Jianhua Peng, Chaoqun(department of chemistry,Zhe jiang normal {3.,Jinhua 3.100 4.

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关键词： gallium adsorption N503 levextrel resin