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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 {2. university, Beijing 100875, china department of chemistry, South china {2. 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.

Dimension and measure theoretic entropy of a subshift in symbolic space

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Chinese Science Bulletin 1997年第14期42卷 1193-1196页

作者： CHEN Ercai and XIONG Jincheng1. department of Astronomy, Nanjing university, Nangjing 2.0093, {2. 2. department of Mathematics, South {2. normal university, Guangzhou 510631, {2. department of Astronomy Nanjing University Nangjing China department of Mathematics South China Normal University Guangzhou China

1 Definitions and resultsWITH the development of the theory of dynamical systems and fractal geometry, one provedthat symbolic dynamics is a powerful tool to study chaos and fractals. It is useful to study thefractal characteristics of symbolic dynamics. In the present note we shall point out the relationbetween the dimension and measure theoretic entropy of any subshift in symbolic space. Weprove here that the Bowen’s formula for Hausdorff dimension holds without Markov struc-ture. A variational principle for dimension is obtained.

关键词： symbolic space subshift measure theoretic entropy dimension.

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

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Journal of Central South university of Technology 2001年第4期8卷 239-243页

作者： TANG Ke wen 1,2.,YI Jian ming 2.ZHOU Chun shan 1,ZHONG Shi an 1 (1. College of chemistry and Chemical Engineering, Central South university, Changsha 410083, {2. 2. College of chemistry and Chemical Engineering, Yueyang normal university 1. College of chemistry and Chemical Engineering Central South University 410083 Changsha China 2. College of chemistry and Chemical Engineering Yueyang Normal University 414000 Yueyang China

Two new chiral stationary phases, 2.3 di O acetyl 6 O trimethylsilyl β cyclodextrin (DATBCD) and 2.6 di O trimethylsilyl 3 O acetyl β cyclodextrin(DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 4143 and 392., the column efficiencies are respectively 3084 and 4198, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer ( k 1) and separation factor(α)of α phenylethanol on DATBCD stationary phase are respectively 8.2. and 1.019.

关键词： capillary gas chromatography silylated and acetylated β-cyclodextrins enantiomeric separation

The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras

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Chinese Science Bulletin 1998年第5期43卷 383-385页

作者： JIANG Cuibo 1 and MENG Daoji 2.1.department of Mathematics,Yantai Teachers university, Yantai 2.402., {2. 2.department of Mathematics,Nankai university,Tianjin 300071, {2.. department of Mathematics Yantai Teachers University Yantai China department of Mathematics Nankai University Tianjin China

The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras over the complex field C are given.

关键词： complete Lie algebra Heisenberg algebra nilpotent radical.

Controlled synthesis and magnetic properties of Fe_3O_4 walnut spherical particles and octahedral microcrystals

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Science china(Technological Sciences) 2008年第11期51卷 1911-1920页

作者： JIAO Hua1,2.& YANG HeQing1 1 Key Laboratory of Macromolecular Science of Shaanxi Province, School of chemistry and Materials Science, Shaanxi normal {2., Xi’an 710062. china 2.department of chemistry and Chemical Engineering, Weinan Teachers {2., Wei nan 714000, china Key Laboratory of Macromolecular Science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an 710062 China department of chemistry and Chemical Engineering Weinan Teachers University Wei nan 714000 China

Magnetite Fe3O4 walnut spherical particles and octahedral microcrystals were suc- cessfully synthesized from K4 [Fe (CN) 6], K3 [Fe (CN) 6] and NaOH reagents via a simple hydrothermal process. And the uniform morphology of octahedral micro- crystals was obtained in the presence of ethylene glycol. The morphology and structure of products were characterized by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the Fe3O4 walnut spherical particles and octahedral microcrystals were single crystals with the face-center cubic structure and with size distributions from 2.2.to 8.6 μm and 1.6 to 12.5 μm, respectively. Their magnetic properties were detected by a vibrating sample magnetometer at room temperature. The walnut spherical parti- cles exhibited a ferromagnetic behavior with the coercive force (Hc), saturation magnetization (Ms) and remanent magnetization (Mr) being 150.57 Oe, 97.634 and 12.05 emu/g, respectively. For the octahedral microcrystals they were 75.2. Oe, 101.90 and 6.69 emu/g, respectively. Different sizes of walnut spherical particles were controlled synthesized through adjusting the NaOH concentration. It was found that ethylene glycol molecules have a significant effect on the formation of Fe3O4 octahedra. A possible mechanism was also proposed to account for the growth of these Fe3O4 products

关键词： a hydrothermal route Fe3O4 walnut spherical particles octahedral microcrystals magnetic property

Thermal oxide synthesis and characterization of Fe_3O_4 nanorods and Fe_2._3 nanowires

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Science china chemistry 2009年第5期52卷 599-604页

作者： JIAO Hua1,2.& YANG HeQing1 1 Key Laboratory of Macromolecular Science of Shaanxi Province, School of chemistry and Materials Science, Shaanxi normal {2., Xi’an 710062. china 2.department of chemistry and Chemical Engineering, Weinan Teacher’s {2., Weinan 714000, china 1. Key Laboratory of Macromolecular Science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an 710062 China 2. department of chemistry and Chemical Engineering Weinan Teacher’s University Weinan 714000 China

Fe3O4 nanorods and Fe2.3 nanowires have been synthesized through a simple thermal oxide reaction of Fe with C2.2.4 solution at 2.0-600℃ for 1 h in the air. The morphology and structure of Fe3O4 nanorods and Fe2.3 nanowires were detected with powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The influence of temperature on the morphology development was experimentally investigated. The results show that the polycrystals Fe3O4 nanorods with cubic structure and the average diameter of 0.5-0.8 μm grow after reaction at 2.0-500℃ for 1 h in the air. When the temperature was 600℃, the samples completely became Fe2.3 nanowires with hexagonal structure. It was found that C2.2.4 molecules had a significant effect on the formation of Fe3O4 nanorods. A possible mechanism was also proposed to account for the growth of these Fe3O4 nanorods.

关键词： thermal oxide process nanorods nanowires C2.2.4 iron sheet

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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Science china chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2.& HU Weixiao1 1. department of Pharmaceutical Science, Zhejiang university of Technology, Hangzhou 310032. {2. 2. department of Applied chemistry, Zhejiang Institute of Science and Technology, Hangzhou 310033, {2. 1. department of Pharmaceutical Science Zhejiang University of Technology 310032 Hangzhou China 2. department of Applied chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

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 {2. university Jinhua 2.1004,china) department of chemistry Zhejiang Normal University Jinhua 231004

The title complex CoCl(ieaa)(C10H7-ieai)(C10H7NH2., C32.32.lCoN4O7, 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 P2./n with a=11.846(2., b=2..912.5), c=12.783(3)? b=116.54(3), V=32.9(1)?, Dc=1.392./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 ≥ 2.(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

Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese Science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. department of chemistry, Northwest {2., Xi’an 710069, china 2. department of chemistry, Wenzhou Teachers College, Wenzhou 32.003, china 3. department of chemistry, Lanzhou {2., Lanzhou 730000, china department of chemistry Northwest University Xi’an China department of chemistry Wenzhou Teachers College Wenzhou China department of chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2.4[OP(OCH3)3]2.(A represents CH2.CH-COO- and CH2.C(CH3)-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2.CH2.C(CH3)-COO]4[OP(OCH3)3]2.is triclinic, with space group P1, a = 1.0512.(13), b = 1.7559(5), c = 1.94479(3) nm, α =91.2.3(14)°,(β = 102.559(6)°,γ= 106.339(13)°, Z = 4 and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.2.098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.