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science china {2. 2006年第2期49卷 162-168页

作者： CUI Wenquan1,3, LIU Li2. FENG Liangrong1, XU Chenghua1, LI Zijian1, Lü Shaojie1 & QIU Fali1 1. Chengdu Institute of Organic chemistry, Chinese Academy of sciences, Chengdu 610041,{2. 2. chemistry department, sichuan university of science & engineering, zigong 643033,{2. 3. Graduate School of the Chinese Academy of sciences, Beijing 100039,{2. Correspondence should be addressed to Qiu Fali 1. Chengdu Institute of Organic chemistry Chinese Academy of Sciences Chengdu 610041 China 3. Graduate School of the Chinese Academy of sciences Beijing 100039 China 2. chemistry department Sichuan University of Science & Engineering Zigong 643033 China

A layered perovskite-type oxide K2.a2.i3O10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2.a2.i3O10 as a co-catalyst with different methods. The dispersion of platinum on K2.a2.i3O10 was determined with HOT method. The photocatalytic activity of Pt/K2.a2.i3O10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2.a2.i3O10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 2.3.88 μmol·h?1 by Pt(2.)/K2.a2.i3O10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2.a_2.i_3O_(10) support

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

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science china {2. 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. department of chemistry, Southwest-{2. 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.

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. department of chemistry,Northwest {2., Xi′an 710065, china 2. department of chemistry and Chemical engineering, Baoji College of Arts and science, Baoji 72.007, china 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Dynamic behavior of polymer surface and the time dependence of contact angle

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science china {2. 2005年第6期48卷 553-559页

作者： WANG Xinping1, CHEN Zhifang1 & SHEN Zhiquan2.1. Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, department of Applied chemistry, Zhejiang Institute of {2. and Technology, Hangzhou 310033, china 2. department of Polymer {2. and engineering, Zhejiang university, Hangzhou 31002., china 1. department of Applied chemistry Zhejiang Institute of Science and Technology Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry 310033 Hangzhou China 2. department of Polymer science and {2. Zhejiang University 310027 Hangzhou China

Time-dependent contact angles were measured by depositing sessile drops of wa-ter on the polymer surfaces and monitoring the drop shape as a function of time. It was found that contact angles decreased sharply with contact time and the equilibrium contact angle was finally attained after a certain time. Values of starting (θ s) and equilibrium contact angles (θ e) obtained by the sessile drop method depend on polymer properties. The Wilhelmy plate technique was used to measure advancing and receding contact angles. The variations of starting (θ s) and equilibrium contact angles (θ e), advancing (θ a) and receding contact angles (θ r) have been studied on the oxidized surface of polymers containing polybutadiene block to explore the cause of time-dependence in contact angle measurement and the meaning of θ s and θ e. The results showed the linear relationships between starting (θ s) and advancing contact angles (θ a), the equilibrium (θ e) and receding contact angles (θ r). The similar relationship was also established between the contact angle hysteresis (θ a?θ r) and differences (θ s ?θ e) in starting contact angles and equilibrium contact angles. Therefore, time-dependence in contact angle measurement was mainly attributed to the surface reconstruction when water drops were deposited on polymer surfaces. The starting contact angle was contributed by the hydrophobic component on polymer surface and the equilibrium contact angle mainly by the hydrophilic component of polymer. These results not only demonstrated the interdependency between two contact angle measurements, the sessile drop method and the Wilhelmy plate technique, but also provided the experimental evidence to explain the cause of time-dependent contact angle. This may also provide a new method to study dynamic behavior of polymer surface.

关键词： contact angle, surface dynamic behavior, polymer surface, dynamic contact angle, time-dependence.

Effect of rare earths on phase transformation in as-cast ZA2. alloy dur-ing compressive creep

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Rare Metals 2003年第4期22卷 259-264页

作者： WEIXiaowei SHENBaoluo DepamnentofAppliedPhysics UniversityofElectronicScienceandTechnologyofChinaChengdu610045China DeparlanentofMetalscience SichuanUniversityChengdu610065China

The effect of the mixed rare earths of Ce on the phase transformation in ascast ZA 2. alloy during compressive was investigated under 37 MPa and at 160 deg C by X-raydiffraction technique and SEM. The results showed that the as cast microstructure of ZA 2.-RE alloyconsisted of a dendritic Al-rich alpha' surrounded by Zn-rich beta' phase, interdendritic epsilonphase and Zn-rich eta phase together with a complex Z phase which was a complex constitute compound,(RE,Cu)Al_5Zn_(16), dispersed in crystal interfaces or branch crystal interfaces and stable duringcompressive creep test at 160 deg C. The phase transformations of ZA 2.-RE alloy, decomposition ofbeta' phase arid four transformation, were delayed by the addition of rare earths, also the lamellarstructure and the spheroidized structure in ZA 2.-RE alloy were finer than in ZA 2. alloy duringcompressive creep test at 160 deg C at the same creep time, and the compressive creep resistance ofZA 2.-RE alloy was higher than that of ZA 2. alloy.

关键词： microstructure change compressive creep rare earths ZA 2. alloy

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of Central South university 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1,2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. department of Metallurgical science and {2., Central South university of Technology, Changsha 410083, china 2. College of chemistry and Chemical {2., Hunan university, Changsha 1. department of Metallurgical science and {2. Central South University of Technology 410083 Changsha China 2. College of chemistry and Chemical engineering Hunan University 410082 Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 18.32.kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion

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 {2. 2004年第3期47卷 251-256页

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

Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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science china {2. 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 College of Materials science and engineering, Shandong {2. of Technology, Zibo 2.5049, china 2.department of chemistry, Jilin {2., Changchun 13002., china 1. College of Materials science and engineering Shandong University of Technology Zibo 255049 China 2. department of chemistry Jilin University Changchun 130023 China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

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 university, Xi’an 710062. china 2.department of chemistry and Chemical engineering, Weinan Teachers university, 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 {2. 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 {2. 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 university, Xi’an 710062. china 2.department of chemistry and Chemical engineering, Weinan Teacher’s university, 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 {2. 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