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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.

Preparation of Pt/K_2.a_2.i_3._(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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science China chemistry 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, China {2.,{3., zigong 643.3., China 3. Graduate School of the Chinese Academy of sciences, Beijing 10003., China Correspondence should be addressed to Qiu Fali Chengdu Institute of Organic chemistry Chinese Academy of Sciences Chengdu China Graduate School of the Chinese Academy of sciences Beijing China chemistry department Sichuan University of Science & Engineering Zigong China

A layered perovskite-type oxide K2.a2.i3.10 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.i3.10 as a co-catalyst with different methods. The dispersion of platinum on K2.a2.i3.10 was determined with HOT method. The photocatalytic activity of Pt/K2.a2.i3.10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2.a2.i3.10. 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.i3.10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2.a_2.i_3._(10) support

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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science China(Technological sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2. ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. department of chemistry, Qingdao {2., Qingdao 2.6071, China 2. department of chemistry, Tsinghua {2., Beijing 100084, China 3. department of Physics, Qingdao {2., Qingdao 2.6071, China department of chemistry Qingdao University Qingdao China department of chemistry Tsinghua University Beijing China department of Physics Qingdao University Qingdao China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

A computer simulation of nucleation and growth of thin films

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science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2.HE Deyan2.LIU Jun2. MA Jiantai3.1. Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong {3., Lanzhou 73.070, China 2. School of Physical science and Technology, Lanzhou {3., Lanzhou 73.000, China 3. School of {3. and {3. engineering, Lanzhou {3., Lanzhou 73.000, China Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou China School of Physical science and Technology Lanzhou University Lanzhou China School of chemistry and chemistry {2. Lanzhou University Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

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 3.2}003. China 3. department of chemistry, Lanzhou {2., Lanzhou 73.000, 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= 106.3.9(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.

Interfacial Microstructure and Properties of Ti(C, N)/Ni Bonded by Transient Liquid-phase Diffusion

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Journal of Wuhan university of Technology(Materials science) 2009年第3期24卷 432-439页

作者：周世权熊惟皓 School of Mechanical science and engineering Huazhong University of Science and Technology department of Mechanical engineering University of Waterloo School of Materials science and engineering Huazhong University of Science and Technology

Effects of the main process parameters（temperature and time） on microstructure and properties of Ti（C, N）/Ni interface bonded by （Cu＋Nb） interlayer in a vacuum diffusion bonding device were investigated. The interfacial microstructures consisted initially of Ni3.b metallic compound and eutectic of Ni3.b ＋ CuNiss, and finally transformed to （Ti, Nb）（C, N）＋Ni3.b near Ti （C, N） and NiCuss ＋ Ni3.b near Ni when diffusion bonding temperature was 1 52.-1 573.K. It was clear that Cu was a constituent in the transient liquid phase （TLP） into which Ni was dissolved by forming Cu-Ni transition liquid. Nb was dissolved in Cu-Ni transition liquid rapidly. Ti （C, N） conld be wetted by resultant Ni-Nb-Cu transient liquid phase which was followed by a little （Ti, Nb）（C, N） solid solution formed at interface. This increased the interface combining capability. Ultimately the interface shear strength was able to reach 140 MPa. The theoretle analysis and experimental results show that the growth of interfacial reaction layer Ni3.b accords with parabola law, and the activation energy of diffusion reaction is 115.0±0.5 kJ/mol, while the diffusion reaction speed constant is 12.53.mm/s^1/2.

关键词： vacuum diffusion bonding transient liquid phase (TLP) diffusion bonding interlayer activation energy

Size distributions and magic number characteristics of cluster configurations formed during solidification processes of liquid metal Al

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science China(Technological sciences) 2006年第2期49卷 172-187页

作者： LIU Rangsu1, LIU Fengxiang1, DONG Kejun1, ZHENG Caixing1, LIU Hairong2. PENG Ping2.& LI Jiyong3.1. department of Physics, Hunan {3., Changsha 410082. China 2. department of Material {3. and engineering, Hunan {3., Changsha 410082. China 3. department of chemistry, Hunan {3., Changsha 410082. China department of Physics Hunan University Changsha China department of Material science and {2. Hunan University Changsha China department of chemistry Hunan University Changsha China

A molecular dynamics simulation study has been performed for a large systemconsisting of 100000 liquid metal Al atoms to investigate the formation and magic numbercharacteristics of the cluster configurations formed during the rapid solidification processes. Thecluster-type index method (CTIM) has been adopted to describe various types of clusterconfigurations. The results indicate that the icosahedral clusters (12.0 12.0) and theircombinations play the most important role in the rnicrostructure transitions during solidificationprocesses; for the cluster configurations of different levels formed by various combinations withdiffering numbers of basic clusters, their size distributions possess obvious magic number sequencewhich is in turn as 13.13., 19(2.), 2.-2.(2.), 3.0}3.(3.0}, 3.-40, 43.44, 48..., (those in bracket arethe corresponding value in liquid state); the magic numbers correspond to the peak value positionsof the cluster numbers for corresponding level formed with various combinations by 1, 2. 3. 4, 5, 6,7, ...basic clusters, respectively. This magic number sequence is in good agreement with theexperimental results obtained by Harris et al. At the same time, this simulation study also gives ascientific and reasonable explanation to these experimental results.

关键词： liquid metal, solidification processes, cluster configuration, magic numbers, computer simulation.

Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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science China(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. Institute of Nuclear Physics and chemistry, China Academy of engineering Physics, Mianyang 62.900, China 2. {2. of physics, Peking {3., Beijing 100871, China 3. Institute of Atomic and Molecular Physics, sichuan {3., Chengdu 610065, China Institute of Nuclear Physics and chemistry China Academy of Engineering Physics Mianyang China department of physics Peking university Beijing China Institute of Atomic and Molecular Physics Sichuan University Chengdu China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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science China chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN Chunyan1, HUANG Yunjie1, LI Jinghong1,2.& CHEN Shaowei3.1. State Key Laboratory of Electroanalytical chemistry, Changchun Institute of Applied chemistry, Chinese Academy of {2.s, Changchun 13.02., China 2. {3. of chemistry, Tsinghua university, Beijing 100084, China 3. {3. of chemistry, university of California, Santa Cruz, Santa Cruz, CA 95064, USA State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied chemistry Chinese Academy of Sciences Changchun China department of chemistry Tsinghua University Beijing China department of chemistry University of California Santa Cruz Santa Cruz USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3.Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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science China chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3. SUN Yele1 & WANG Zifa3.1. The Center for Atmospheric Environmental Study, department of chemistry, Beijing Normal {2., Beijing 100875, China 2. Center for Atmospheric chemistry Study, department of Environmental science & engineering, Fudan {2., Shanghai 2.043., China 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, Beijing 10002., China The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing China Center for Atmospheric chemistry Study Department of Environmental Science & Engineering Fudan University Shanghai China Institute of Atmospheric Physics CAS LAPC/NZC Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.0}―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （3.%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52.―83.）, 79% （52.―93.）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.