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science china Chemistry 2009年第4期 471-474页

作者： LI Xin1,LI Hui2,YU ShuYan1,4 & LI YiZhi3 1 laboratory for Self-Assembly Chemistry,department of Chemistry,Renmin university of china,Beijing 100872,china 2 School of materials science and engineering,East china university of science and Technology,Shanghai 200237,china 3 state Key laboratory of Coordination Chemistry,Coordination Chemistry Institute,nanjing university,nanjing 210093,china 4 state Key laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of sciences,Fuzhou 350002,china

The anion coordination complex,[ClPt(bpt)4]Cl (bpt=N,N'-bis(3-pyridylmethyl)-2-thiourea),was synthesized and studied by X-ray crystal structure analysis,NMR and FAB mass spectra. In the solid state,the Pt(bpt)4 anion receptor adopts a cone conformation to bind the chloride anion through hydrogen bonds and electrostatic interaction in which the four branches of the thiourea ligands bind the chloride anion to form N-H…Cl-hydrogen bonds (3.49-3.81). The entraped chloride anion is situated above the Pt(Ⅱ) center at 3.52 . Further second-sphere coordination assemby from the Pt(bpt)4 core with 8 zinc(Ⅱ) tetraphenylporphyrins (ZnPr) is discussed.

关键词： anion coordination platinum(Ⅱ) complex supramolecular chemistry hydrogen bonds second-sphere coordination

Kinetic limit for incubation period of primary phase produced by the combination reaction between two solid heterogeneous pure metals

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science china(Technological sciences) 2008年第12期51卷 2232-2243页

作者： XIONG JiangTao1,2,LI JingLong1,ZHANG FuSheng1,LIN Xin2 & HUANG WeiDong2 1 Shaanxi Key laboratory of Friction Welding Technologies,Northwestern Polytechnical university,Xi’an 710072,china 2 state Key laboratory of solidification Processing,Northwestern Polytechnical university,Xi’an 710072,china Shaanxi Key laboratory of Friction Welding Technologies Northwestern Polytechnical University Xi’an 710072 China state Key laboratory of solidification Processing Northwestern Polytechnical University Xi’an 710072 China

An irreversible thermodynamics model was constructed to study the combination reaction of two heterogeneous pure metals in diffusion bonding based on the theorem of minimum entropy production and the Curie *** correlation between the irreversible reaction and diffusion was discussed,which provided the kinetic inevitability of an incubation period of a primary *** analytical descriptions of the incubation period and the kinetically critical grain size of the primary phase were *** of the experimental results of Al/Mo interfacial reaction with the calculations indicated that the performed theoretical analysis was reliable.

关键词： incubation period primary phase interfacial reaction irreversible thermodynamics

Synthesis of LaFeO_3 catalytic materials and their sensing properties

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science china Chemistry 2009年第12期52卷 2106-2113页

作者： BAI ShouLi,SHI BingJie,MA LiJing,YANG PengCheng,LIU ZhiYong,LI DianQing & CHEN AiFan state Key laboratory of Chemical Resource engineering,College of science,Beijing university of Chemical Technology,Beijing 100029,china 1. state Key laboratory of Chemical Resource engineering College of Science Beijing University of Chemical Technology Beijing 100029 China

LaFeO3 is a p-type semiconductor catalytic material of perovskite structure (ABO3). Its magnetic and photocatalytic properties have been widely investigated,but the gas sensing properties are seldom reported,especially for toxic and noxious gases of NO2 and CO. The nanocomposites of LaFeO3 and LaFe1-xMgxO3 (x = 0.02,0.04,0.06) were prepared by various methods of the wet chemical process and their exact composition,crystal structures,grain sizes,specific surfaces,morphology and the electronic interaction between components were characterized by EDX,XRD,BET,SEM and XPS analysis. The sensors based on these nanocomposites have been fabricated to examine the sensing responses to gases,and the results show that these sensors exhibited high response to both oxidizing gas (NO2) and reducing gas (CO),and the response was greatly enhanced by the surface modification of MgO. The additive method,amount of additives,and their effects on the LaFeO3 structure and gas response have been analyzed and discussed by temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopic (XPS) analysis.

关键词： LaFeO3 NO2 CO sensing properties MgO-modified

Mechanism of fluorescent cocoon sex identification for silkworms Bombyx mori

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science china(Life sciences) 2010年第11期53卷 1330-1339页

作者： ZHANG YuQing1,2, YU XiaoHua1,2, SHEN WeiDe1,2, MA YongLei1,2, ZHOU LiXia1,2, XU NaiXi1,2 & YI ShuQian1,2 1state engineering laboratory of Modern Silk, Soochow university, Suzhou 215123, china 2Silk Biotechnology Key laboratory of Suzhou City, Medical College of Soochow university, Suzhou 215123, china 1. state engineering laboratory of Modern Silk Soochow University Suzhou 215123 China2. Silk Biotechnology Key Laboratory of Suzhou City Medical College of Soochow University Suzhou 215123 China

By using silkworms,Bombyx mori, fluorescent cocoon sex identification (FCSI) as an experimental material, direct fluorescence spectrometry of the cocoon surface indicates that the fluorescent color of silkworm cocoons is made up of two peaks of yellow and blue-purple fluorescence emission. The fluorescent difference between male and female cocoons is attributed to the differential absorption of yellow fluorescent substances by the midgut tissue of 5th instar female silkworms. Thin layer chromatography (TLC) and fluorescent spectra indicate that blue-purple fluorescent substances are composed of at least five blue-purple fluorescent pigments, and yellow fluorescent substances are made up of at least three. UV spectra and AlCl3 color reaction show that the three fluorescent yellow pigments are flavonoids or their glycosides. Silkworm FCSI is due to selective absorption or accumulation of the yellow fluorescent pigments by the posterior midgut cells of female 5th instar larvae. The cells of the FCSI silkworm midgut, especially the cylinder intestinal cells of the posterior midgut have a component which is a yellow fluorescent pigment-specific binding protein that may be vigorously expressed in the 5th instar larvae.

关键词： silkworm fluorescence cocoon sex identification pigment midgut accumulation

OPTIMIZATION OF DISPLACEMENT AND GLIDING PATH AND IMPROVEMENT OF PERFORMANCE FOR AN UNDERWATER THERMAL GLIDER

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Journal of Hydrodynamics 2010年第5期22卷 618-625页

作者： YANG Hai MA Jie state Key laboratory of Ocean engineering Shanghai Jiao Tong University Shanghai 200030 China

The underwater thermal glider utilizes ocean thermal energy to change its buoyancy, which enables it to ascend and descend. A Phase Change material （PCM） as the working fluid inside the thermal engine tubes is sensitive to the surrounding seawater temperature, whose effects are different with the various displacements and gliding angles of the glider. In this paper, the effects of the displacement and the gliding angle on the performance of the thermal engine were studied numerically and experimentally. On this basis, the ways to eliminate the negative effect of a thermocline on the performance of the thermal engine were obtained. The results show that the displacement and gliding angle affect the transition time of the PCM. There exist the threshold values of the displacement and gliding angle for the normal work of thermal engine. There are two means of eliminating the negative effect of a thermocline on the performance of the thermal engine and improving glider performance： one is to increase the displacement, and the other is to decrease the absolute value of the gliding angle. There is also another better way to improve glider performance.

关键词： displacement gliding angle underwater thermal glider Phase Change material (PCM)

CFD simulation of pressure fluctuation characteristics in the gas-solid fluidized bed:Comparisons with experiments

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Petroleum science 2011年第2期8卷 211-218页

作者： Wang Qingcheng Zhang Kai Gu Hongyan Beijing Shenwu Thermal Energy Technology Co. LTD Beijing 102200 China state Key laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China national engineering Lab for Biomass Power Generation Equipment North China Electric Power University Beijing 102206 China Electrical engineering College Guizhou University Guiyang 550025 China

A simple hydrodynamic model based on two-fluid theory, taking into account the effect of discrete particles on both the gas- and solid-phase momentum equations, was used to numerically investigate the pressure fluctuation characteristics in a gas-solid fluidized bed with the aid of CFX 4.4, a commercial CFD software package, by adding user-defined Fortran subroutines. Numerical simulations together with typical experimental measurements show that pressure fluctuations originate above the distributor when a gas pulse is injected into the fluidized bed. The pressure above the bubble gradually increases due to the presence of a rising bubble. When the bubble passes through the bed surface, the pressure near the bed surface gradually decreases to a lower value. Moreover, the pressure signals in the bubbling fluidized beds show obviously periodic characteristics. The major frequency of pressure fluctuations at the same vertical position is affected slightly by the operating gas velocity, and the amplitude of pressure fluctuations is related to both the operating gas velocity and the vertical height. In this study, the influence of the operating gas velocity on the pressure wave propagation velocity can be ignored, and only two peak frequencies in the power spectrum of the pressure fluctuations are observed which are associated with the bubble formation above the distributor and its eruption at the bed surface.

关键词： Gas-solid fluidized bed CFD simulation experimental measurements propagation ofpressure fluctuations pressure wave velocity pressure fluctuation frequency

microstructure and Wear Resistance Evolution of HVOFSprayed WC-(W,Cr)_2C-Ni Coating with Post Heat Treatment In Air Atmosphere

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稀有金属材料与工程 2012年第S1期41卷 388-393页

作者： Hou Guoliang1,2,Zhou Huidi1,An Yulong1,2,Liu Guang1,2,Chen Jianmin1,Chen Jie1,2 1 state Key laboratory of solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of sciences,Lanzhou 730000,china 2 Graduate university,Chinese Academy of sciences,Beijing 100049,china Chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

WC-(W,Cr)2C-Ni coating was prepared on 1Cr18Ni9Ti stainless steel and C-276 Ni-base Hastelloy by high velocity oxy-fuel(HVOF)*** effect of post heat treatment in air atmosphere on the microstructure,phase composition,microhardness,fracture toughness,and wear resistance of HVOF-sprayed WC-(W,Cr)2C-Ni coating was *** microstructure and phase composition of the coatings were analyzed by means of field emission scanning electron microscopy(FESEM)and X-ray diffraction(XRD).The microhardness and fracture toughness of the coatings were measured using a microhardness tester and a Vickers hardness ***,dry friction and wear behavior of the coatings sliding against Si3N4 ball was investigated using an oscillating friction and wear tester;and the worn surfaces of the coatings were analyzed by means of scanning electron microscopy(SEM).It was found that heat treatment within 500-800°C resulted in crystallization of amorphous phase in as-sprayed coating,generating nanoscale new phases such as NiWO4,CrWO4 and ***,heat treatment led to increase of the microhardness of as-sprayed coating,and the highest microhardness was obtained after heat treatment at 800°*** fracture toughness and wear resistance of the as-sprayed coating increased with increasing heat treatment temperature up to 700°C but tended to decrease with further elevating *** other words,the mechanical properties and wear resistance of the as-sprayed coatings were worsened owing to excessive growth of oxidation grains and depletion of ductile Ni binder after heat treatment above 700°*** it was suggested that as-sprayed ceramic composite coating should be post heat treated in air at a moderate temperature of 700°C so as to achieve the optimized mechanical properties and wear resistance.

关键词： HVOF WC-(W,Cr)2C-Ni coating post heat treatment microstructure wear resistance

Photoresponsive organogel and organized nanostructures of cholesterol imide derivatives with azobenzene substituent groups

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Progress in Natural science:materials International 2012年第1期22卷 64-70页

作者： Tifeng Jiao a,b,c,Yujin Wang a,Fengqing Gao a,Jingxin Zhou a,Faming Gao a a Hebei Key laboratory of Applied Chemistry,College of Environmental and Chemical engineering,Yanshan university,Qinhuangdao 066004,china b College of Chemistry & materials engineering,Wenzhou university,Wenzhou 325027,china c state Key laboratory of solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of sciences,Lanzhou 730000,china [a] Hebei Key laboratory of Applied Chemistry College of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China [b] College of Chemistry & materials engineering Wenzhou University Wenzhou 325027 China [c] state Key laboratory of solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Two new cholesterol imide derivatives with azobenzene substituent groups have been *** compounds possess headgroups of hydrogen or methyl units,*** gelation test revealed that a subtle change in the headgroup of azobenzene segment produced a dramatic change in the gelation behavior of both *** compound with headgroups of hydrogen units only gelated N,N-Dimethylformamide(DMF),while the other compound with headgroups of methyl units cannot gelate any solvent tested *** DMF gel and solution of the gelator,the reversible photoisomerization transitions by irradiation with ultraviolet(UV) and visible light are investigated by UV-vis absorption spectra,Fourier transform infrared spectrometer,scanning electron microscope,atomic force microscope,and X-ray diffraction *** UV irradiation of the gel,trans-cis photoisomerization of the azobenzene groups occurs,the change in molecular polarity leads to the breaking of van der Waals interactions,resulting in the gel-sol *** gel can be recovered by the reverse cis-trans photoisomerization after exposure to visible *** and spectral studies reveal that the gelator molecules selfassemble into one-dimensional fibers,which further crossed-linked to form regular *** results afford useful information for the development of new versatile low molecular mass gelators and soft matter.

关键词： Organogel Cholesterol Azobenzene Photoisomerization Soft material

Influence of Molecular Weight of PEO on Performance of Quasi-solid-state Dye-sensitized Solar Cells

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Journal of Wuhan university of Technology(materials science) 2010年第2期25卷 218-222页

作者：沈小林 School of materials science & engineering Xi’an Jiaotong University

Quasi-solid-state dye-sensitized solar cells （DSCs） were prepared using gel electrolyte gelated by poly（ethylene-oxide）（PEO） with different molecular weight. With the increase in PEO molecular weight, the short circuit current densities （Jsc） increase significantly, which is related to the increase in I - diffusion due to the increase in free volume of gel electrolyte. However, only a slight increase in open voltage （Voc） is observed, which is explained by the decrease in dark current arising from the reduction of triiodide （I3^-） by conduction band electrons.

关键词： dye-sensitized solar cell poly(ethylene oxide) gel electrolyte molecular weight