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(2+1)-Dimensional Electron Acoustic Solitary Waves in an Unmagnetized Collisionless Plasma with Vortex-Like Hot Electrons

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Communications in Theoretical Physics 2007年第2期47卷 339-342页

作者： LIN Mai-Mai DUAN Wen-Shan department of Physics,Northwest,Normal university,lanzhou 73.070,{3. department of Physics Northwest Normal University

In this paper,(2+1)-dimensional electron acoustic waves (EAW) in an unmagnetized collisionless plasmahave been studied by the linearized method and the reductive perturbation technique,*** dispersionrelation and a modified Kadomtsev Petviashvili (KP) equation have been obtained for the EAW in the plasma consideringa cold electron fluid and a vortex-like hot *** is found from some numerical results that the parameter β (theratio of the free hot electron temperature to the hot trapped electron temperature) effects on the amplitude and thewidth of the electron acoustic solitary waves (EASW).It can be indicated that the free hot electron temperature andthe hot trapped electron temperature have very important effect on the characters of the propagation for the EASW.

关键词： electron acoustic solitary wave vortex-like hot electrons reductive perturbation method

Photocatalytic performance of TiO_2 immobilized on polystyrene (PS) thin film for mineralization of pollutants

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Rare Metals 2003年第2期22卷 137-143页

作者： GAO Yuan, YU Wei, CHEN Baohua, MA Yongxiang, and LI Hulindepartment of Chemistry, lanzhou university, lanzhou 73.000,{3. (Receeived 2002-02-26) department of Chemistry Lanzhou University Lanzhou 730000

A new photocatalyst, TiO_2 powder immobilized on polystyrene (PS) thin films,was prepared using a novel method and its photocatalytic activity on the photodegradation ofacridine dye in aqueous solution was tested. By this method, the crystal form and grain size of theimmobilized TiO_2 were well maintained. Compared with TiO_2 powder, the photocatalytic activity ofTiO_2/PS thin films was not significantly reduced. The catalyst is stable and can be reused severaltimes without the loss of activity, which makes wastewater treatment using this photocatalyticdegradation technique of this way possible in the practical application.

关键词： physical chemistry loaded photocatalyst TiO_2 acridine dye fluidifying sedimentation container

Determination of Trace Amount of Yttrium with Bromopyrogallol Red by solid-phase Spectrophotometry

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Rare Metals 2001年第3期20卷 202-204页

作者： Jinzhang Gao,Gang Ni, Li Yuan, Jingwan Kang department of Chemistry, Northwest Normal university, lanzhou 73.070,{3. NW Normal Univ Dept Chem Lanzhou 730070 Peoples R China

A simple and sensitive method for the determination of trace amount of yttrium by solid-phase spectrophotometry has been studied. Yttrium can form a 1 : 1 complex with bromopyrogallol red (BPR) on resin, which was determined directly at 605 nm, pH=6.5. It has a highly sensitivity (epsilon = 6.3.x 10(6)) which is 3.0-fold higher than the corresponding spectrophotometry in solution. The method was applied to the determination of yttrium in churchite.

关键词： solid-phase spectrophotometry bromopyrogallol red (BPR) yttrium

STUDY OF THE MECHANISM OF LOESS COLLAPSE

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Science china Chemistry 1989年第5期32卷 604-617页

作者：杨运来 department of geology Lanzhou University

In this paper, firstly, the amount of collapsible space is statistically determined from the pore-size distributions of loess slices before and after collapse by using a polarizing microscope. Then, the characteristics of the structure and the copulation of loess grains are studied, and the copulations which decrease in strength upon contact with water are discovered. Lastly, by studying the joint action of external causes——a certain load and a certain moisture content——and internal conditions, the mechanism of loess collapse is advanced.

关键词： mechanism of loess collapse collapsible spece loose structure hydrostabil cementation hydrolabil sementation.

Oxyfunctionalization of ketones bearing α-methylene group with piperidine oxoammonium *** of α-diketones from monoketones

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Chinese Journal of Chemistry 1996年第3期14卷 252-258页

作者： LIU, You-Cheng REN, Tan GUO, Qing-Xiang National Laboratory of Applied Organic Chemistry, lanzhou university,lanzhou, Gansu 73.000,{3. department of Modern Chemistry, university of Science and Technology of{3.,Hefei, Anhui 23.026,{3. National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China department of Modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China department of Modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China [*]Address correspondence to this author at university of Science and Technology of china.

A facile method for the title transformation is described. The reaction of 2,2,6,6-tetramethyl-4-methoxypiperidine oxoammonium chloride (1b) and ketones bearing a-methylene group in acetonitrile proceeded smoothly to give the a-oxyfunctionalized coupling products (6a-h). These coupling products decomposed upon heating in acidic medium to produce a-diketones (7a-h) in good to excellent yields.

关键词： Piperidine oxoammonium salt monoketones,α-diketones synthesis

Studies on condensed heterocyclic compounds *** and antibacterial activity of 3.(4'-pyridyl)-6-aroylamino/arylamino-S-triazolo[3.4-b]-1,3.4-thiadiazoles

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Chinese Journal of Chemistry 1992年第1期10卷 59-64页

作者： ZHANG,Zi-Yi CHEN,Xin department of Chemistry,lanzhou university,lanzhou 73.000 department of Chemistry Lanzhou University Lanzhou 730000

3.(4′-Pyridyl)-4-amino-5-mercapto-1,2,4-triazole(1)reacted with aroyl isothiocyanates 2a-1 to yield twelve novel 3.(4′-pyridyl)-6-aroylamino-S-triazolo[3.4-b]-1,3.4-thiadiazoles,4a-1. Triethylamine was necessary for the condensation of 1 with phenyl isothiocyanate(3.to give 3.(4′- pyridyl)-6-phenylamino-S-triazolo[3.4-b]-1,3.4-thiadiazole(6).The structures were confirmed by the elemental and spectral *** antibacterial activity against ***,***,E. aerogenes and *** was observed preliminary.

关键词： Studies on condensed heterocyclic compounds II.Synthesis and antibacterial activity of 3 aroylamino/arylamino-S-triazolo[3.4-b pyridyl thiadiazoles II

The synthesis, bioactivity and paramagnetic resonance of angiotensin Ⅱ and its spin labelled derivative

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Chinese Science Bulletin 1997年第21期42卷 1843-1846页

作者： WANG Rui, LI Xiaoxu, HU Xiaoyu, NI Jingman, LI Changling and LU Jingfen1. department of Biology, State Key Laboratory of Applied Organic Chemistry, lanzhou 73.000, china 2. department of Chemistry, lanzhou university, lanzhou 73.000 3. State Key Laboratory of Natural and Biomimetic Drugs, Beijing Medical U-niversity, Beijing 100083. china. department of Biology State Key Laboratory of Applied Organic Chemistry Lanzhou China department of Chemistry Lanzhou University Lanzhou State Key Laboratory of Natural and Biomimetic Drugs Beijing Medical University Beijing China

ANGIOTENSIN Ⅱ(Ang Ⅱ) is an important constituent in renin-angiotension system (RAS).The amino acid sequence of Ang Ⅱ is DRVYIHPF. Ang Ⅱ plays an important role both inmaintenance of normal blood pressure and in occurrence of hypertension. Ang Ⅱ binding re-ceptor can induce many kinds of physiological effects. Spin labeling is an effective method thatgreatly deepened the knowledge in structure, movement and interaction of biologicalmolecules. For example, it has been used in studying interaction of antigen and antibody suc-

关键词： spin labelled angiotensin Ⅱ solid phase peptide synthesis bioactivity electron spin resonance.

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 university, Qingdao 266071, china 2. department of Chemistry, Tsinghua university, Beijing 100084, china 3. department of Physics, Qingdao university, Qingdao 266071, china 1. department of Chemistry Qingdao University Qingdao 266071 China 2. department of Chemistry Tsinghua University Beijing 100084 China 3. department of Physics Qingdao University Qingdao 266071 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.

Microstructure and properties of thermal-sprayed NiCrWRE coatings

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Rare Metals 2008年第3期27卷 261-265页

作者： ZHANG Zhenyu WANG Zhiping LIANG Bunv Mechanical Engineering department Lanzhou Polytechnic College Lanzhou 730050 China State Key Laboratory of New Nonferrous Metal Materials Lanzhou University of Technology Lanzhou 730050 China

The powders of NiCrW and NiCrWRE alloys were flame sprayed on a medium-carbon steel substrate by thermal spray welding. The micro- structure and tribological behavior of coatings were studied experimentally by means of scanning electron microscopy （SEM）, field emission gun scanning electron microscope （FEGSEM）, and wear tests. The addition of CeO2 modifies the coating morphology from a needle-like structure to a roughly cubic morphology; the refining and purifying effect of rare earth elements makes the microstmcture more compact and finer. Analysis of the worn surfaces reveals that the coatings with CeO2 addition show improved abrasive wear resistance over those without CeO2. By adding CeO2, the hardness of the coatings is significantly increased, and the wear resistance of the coatings is enhanced.

关键词： NiCrWRE microstructure thermal-sprayed coatings wear resistance