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Science china chemistry 2008年第2期51卷 120-127页

作者： WEI RuiPing1,2, GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented chemical engineering, college of chemistry and chemical engineering, nanjing Uni- versity of Technology, nanjing 210009, china 2.college of chemistry and chemical engineering, southeast university, nanjing 2.1189, china State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China college of chemistry and chemical engineering Southeast UniversityNanjing 211189China

The bimetal-bearing (CePt or LaPt) 12-tungstophosphoric acid (H3PW12O40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2-chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 250℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%.

关键词： hydroisomerization of n-heptane bimetal catalyst heteropoly acid USY platinum

A NOVEL INTERPRETATION OF CONCENTRATION DEPENDENCE OF VISCOSITY OF DILUTE POLYMER SOLUTION

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Chinese Journal of Polymer Science 2000年第1期18卷 57-67页

作者： Yan Pan Rong-shi Cheng college of Material Science and engineering, South china university of Technology, Guangzhou 510641, china college of chemistry and chemical engineering, nanjing university, nanjing 210093, china S china Univ Technol Coll Mat Sci & Engn Guangzhou 510641 Peoples R China nanjing Univ Coll Chem & Chem Engn Nanjing 210093 Peoples R China

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence

Mesoporous Si-MCM-48 membrane prepared by pore-filling method

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Science china(Technological Sciences) 2010年第4期53卷 1064-1068页

作者： XU DeKan & FAN YiQun State Key Laboratory of Materials-Oriented chemical engineering,college of chemistry and chemical engineering,nanjing university of Technology,nanjing 210009,china 1. State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

Mesoporous MCM-48 membranes were prepared on asymmetric zirconia tubular support with an average pore size of 0.2 μm by hydrothermal *** support should be pretreated with H2O as a pore-filling substance to prevent the sol solution from infiltrating into the support *** SEM showed that the MCM-48 membrane was composed of tightly-connected spherical *** single gas N2 and H2 permeation experiments confirm that crack-free membrane could be prepared by pore-filling method.N2 permeance of MCM-48 membrane,synthesized by secondary growth,can reach 5.66×10-7 mol/Pa·s·m2,and the H2/N2 separation factor was 3.47 under trans-membrane pressure of 0.05 MPa.

关键词： MCM-48 mesoporous membrane pore-filling

Polymer-assisted nanoparticulate contrast-enhancing materials

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Science china chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2,WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering,college of chemistry & chemical engineering,nanjing university,nanjing 210093,china 2National Laboratory of Solid State Microstructure,Department of Material Science and engineering,nanjing university,nanjing 210093,china 3Key Laboratory of Analytical chemistry for Life Science,Ministry of Education,School of chemistry and chemical engineering,nanjing university,nanjing 210093,china 1. Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing 210093 China3. Key Laboratory of Analytical Chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing 210093 China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

A study on methane coupling to acetylene under the microwave plasma

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Science china chemistry 2010年第1期53卷 231-237页

作者： SHEN ChangSheng1,SUN YongZhi1,SUN DeKun2 & YANG HongSheng1 1State Key Laboratory of Millimeter Waves School of Electronic Science and engineering,southeast university,nanjing 210096,china 2School of chemistry and chemical engineering,nanjing university,nanjing 210093,china 1. State Key Laboratory of Millimeter Waves School of Electronic Science and engineering Southeast University Nanjing 210096 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

By optimizing the microwave chemistry reactor made of the rectangular waveguide resonator,the methane conversion(the maximum 93.7%),the C2 hydrocarbon yield(the maximum 91.0%) and the acetylene yield(the maximum 88.6%) were all greatly increased under the microwave ***,for the optimal reactor,the change of the methane conversion and the C2 hydrocarbon yield is little within the range of the pressures in the *** C2 hydrocarbon is mainly made up of acetylene,and the selectivity for acetylene is above 90%.Energy yield and space time yield of acetylene are also *** emission spectroscopy(OES) was adopted for the diagnosis of methane coupling to acetylene under microwave *** excited species(CH,C2,H2,Hα) were detected in the spectra range of 300-750 *** on the products and the excited species,the reaction mechanism of methane coupling under microwave plasma was investigated,using the thermodynamics and kinetics of the chemical reaction.

关键词： microwave plasma methane acetylene

Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science china chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2,SUN Hao2,LIN Chen2,ZHANG GuangQian2,LI GuiGen4 & PAN Yi2,3 1 Department of chemistry,Huaiyin Normal university,Huai’an 221003,china 2 School of chemistry and chemical engineering,nanjing university,nanjing 210093,china 3 State Key Lab of Coordination chemistry,nanjing university,nanjing 210093,china 4 Department of chemistry and Biochemistry,Texas Tech university,Lubbock,Texas 79409-1061,USA 1. Department of chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

Cycloaddition mechanism for the resin-OsO_4-catalyzed of styrene: A DFT study

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Science china chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG Ran2 1 college of chemical engineering, Gansu Unite university, Lanzhou 730000, china 2.college of chemistry and chemical engineering, Sun Yat-sen university, Guangzhou 510275, china college of chemical engineering Gansu Unite UniversityLanzhou 730000China college of chemistry and chemical engineering Sun Yat-sen UniversityGuangzhou 510275China

The postulated intermediates in the base-free and base-assisted addition of OsO4 to styrene have been investigated at the B3LYP/6-311G** level of the theory. N(CH3)2(Ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2+3] addition was found to be favorable with an activation of 2+2] cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NBO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory

Preparation of Exo-tetrahydrodicyclopentadiene Using SiW/Hβ Catalyst

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china Petroleum Processing & Petrochemical Technology 2011年第3期13卷 41-46页

作者： Kang Zhuozhuo Wu Wenliang Zhou Zhiwei (college of chemistry and chemical engineering,nanjing university of Technology,nanjing 210009) nanjing Univ Technol Coll Chem & Chem Engn Nanjing 210009 Peoples R China

Exo-tetrahydrodicyclopentadiene （exo-TCD） is an important high-energy fuel. Silicotungstic acid （SiW） immobilized on H-type β zeolite （Hβ） at room temperature were used to prepare the Hβ zeolite catalysts with different SiW contents. Catalytic performances of the catalysts were investigated during the preparation of exo-TCD via isomerization of endo-tetrahydrodicyclopentadiene （endo-TCD）. The properties of catalysts were characterized by XRD, temperature pro- grammed desorption of ammonia （NHa-TPD）, FT-IR, and N2-adsorption techniques. SiW was highly dispersed on the surface of Hβ zeolite, and the 10% SiW/Hβ zeolite catalyst had the highest amount of weak acidity among all SiW/Hβ zeolite catalysts. The influence of different factors on isomerization reaction was investigated. At a reaction temperature of 240 ℃, a n（cyclohexane） / n（endo-TCD） ratio of 10, a m（catalyst）/m（endo-TCD） ratio of 0.3, an initial pressure of 1.0 MPa, and a reaction time of 1.5 h in the presence of 10% SiW/Hβ catalyst calcined at 400 ℃, the conversion of endo-TCD reached up to 92.0%, with the yield of exo-TCD equating to 51.0%.

关键词： exo-tetrahydrodicyclopentadiene endo-tetrahydrodicyclopentadiene Hβ zeolite silicotungstic acid (SiW)

Adsorption Breakthrough of Benzene in the Fixed Bed of Modified Activated Carbon under Different Humidity Conditions

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Journal of Wuhan university of Technology(Materials Science) 2010年第3期25卷 499-503页

作者：李晶 college of chemistry and chemical engineering Zhongkai University of Agriculture and Engineering

The breakthrough curves of benzene and water on modified activated carbons（ACs） were ***-programmed desorption（TPD） experiments were conducted to measure the TPD curves of benzene and water on modified and unmodified ACs and to estimate the activation energy for the desorption of benzene on the modified *** with unmodified ACs,two modified ACs were prepared by using two different types of silane,designated by KH560 and *** results showed that the activation energy for the desorption of benzene on KH560/AC and 1706/AC was higher than that on unmodified *** addition,the activation energy for the desorption of water on KH560/AC and 1706/AC was lower than that on unmodified *** breakthrough curves of benzene obtained from the experimental observations under different humidity conditions were compared with the results of the TPD *** results show that the modified ACs are less affected by water,whereas the unmodified ACs are more affected by water,indicating that surface modification by organosilane compounds can improve the adsorption of benzene on the activated carbo,which weakens the adsorption of water.

关键词： activated carbon benzene water TPD activation energy of desorption breakthrough curves

Synthesis and purification of trialkyl compounds of gallium and indium

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Rare Metals 2002年第1期21卷 1-6页

作者： SHU Wangen, ZHOU Zhongcheng and LI Xiong chemistry and chemical engineering college, Central South university, Changsha 410083, china chemistry and chemistry engineering college Central South University Changsha 410083 chemistry and chemical engineering college Central South University Changsha 410083

The The research progress in trialkyl compounds of gallium andindium was discussed from two aspect, one was the chemical synthesisof the compounds and the other was the purification of them. Thereare three synthesis routes be- ing reported in the first aspect, *** route staring form pure metal, the route starting from the puremetal trihalides, and the electrochemical route. In the secondaspect, the purifying methods of decomposition-distillation and zonerefining were reviewed.

关键词： trialkyl compounds gallium nd indium synthesis purification