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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 211189, china State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China college of chemistry and chemical engineering Southeast University Nanjing China

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

Cross-linked Polyethylenimine as Potential DNA Vector for Gene Delivery with High Efficiency and Low Cytotoxicity

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 780-787页

作者： Wei DONG~(1,2) Guang-Hui JIN~1 Shu-Feng LI~(1,3) Qi-Ming SUN~1 Ding-Yuan MA~1 Zi-Chun HUA~1 1 State Key Laboratory of Pharmaceutical Biotechnology,college of Life Science,nanjing university,nanjing 210093,china 2 School of chemical engineering nanjing university of Science and Technology,nanjing 210094,china 3 college of Basic Medical Science,southeast university,nanjing 210009,china State Key Laboratory of Pharmaceutical Biotechnology College of Life Science Nanjing UniversityNanjing 210093 China School of chemical engineering Nanjing University of Science and TechnologyNanjing 210094 China college of Basic Medical Science Southeast UniversityNanjing 210009 China

Polyethylenimine (PEI) has been known as an efficient gene carrier with the highest cationiccharge potential.High transfection efficiency of PEI,along with its cytotoxicity,strongly depends on itsmolecular weight.To enhance its gene delivery efficiency and minimize cytotoxicity,we have synthesizedsmall cross-linked PEI with biodegradable linkages and evaluated their transfection efficiencies in vitro.Inthis study,branched PEI with a molecular weight of 800 Da was cross-linked by small diacrylate[1,4-butanediol diacrylate or ethyleneglycol dimethacrylate (EGDMA)] for 2-6 h.The efficiencies of thecross-linked PEI in in vitro transfection of plasmid DNA containing enhanced green fluorescent protein(EGFP) reporter gene were assessed in melanoma B 16F10 cell line and other cell lines.Flow cytometrywas used to quantify the cellular entry efficiency of plasmid and the transgene expression level.Thecytotoxicities of the cross-linked PEI in these cells were evaluated by MTT assay.EGDMA-PEI 800-4h,atypical cross-linked PEI reported here,mediated a more efficient expression of reporter gene than thecommercially available 25-kDa branched PEI control,and resulted in a 9-fold increase in gene deliveryin B16F10 cells and a 16-fold increase in 293T cells,while no cytotoxicity was found at the optimizedcondition for gene delivery.Furthermore,the transfection activity of polyplexes was preserved in thepresence of serum proteins.

关键词： polyethylenimine gene delivery cytotoxicity B16F10 293T cell line

Propane Dehydrogenation over PtSnNa Catalyst Supported on La-ZSM-5 Zeolite

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china Petroleum Processing & Petrochemical Technology 2010年第3期12卷 18-24页

作者： Huang Li Zhou Yuming Zhang Yiwei Li Qingning Tian Xiaoming (School of chemistry and chemical engineering,southeast university,nanjing 211189) School of chemistry and chemical engineering Southeast University Nanjing 211189 China

有 La 的不同内容的 La-ZSM-5 沸石被材料的物理化学的性质是的热水的 method.The 综合英尺红外分析的 studied.The 结果显示 La 可能被合并到分析显示出的 ZSM-5 zeolite.The NH3-TPD 的框架沸石的弱酸地点的数量与连续地增加的 La ... 详细信息

有 La 的不同内容的 La-ZSM-5 沸石被材料的物理化学的性质是的热水的 method.The 综合英尺红外分析的 studied.The 结果显示 La 可能被合并到分析显示出的 ZSM-5 zeolite.The NH3-TPD 的框架沸石的弱酸地点的数量与连续地增加的 La 减少了 content.Afterwards ， La-ZSM-5 沸石被用作对丙烷 dehydrogenation.The 测试结果的 PtSnNa

关键词：分子筛催化剂丙烷脱氢 ZSM La 物理化学性能程序升温脱附水热法合成催化剂表面

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 华南理工大学广东广州

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 State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China

Mesoporous MCM-48 membranes were prepared on asymmetric zirconia tubular support with an average pore size of 0.2 μm by hydrothermal method.The support should be pretreated with H2O as a pore-filling substance to prevent the sol solution from infiltrating into the support pores.The SEM showed that the MCM-48 membrane was composed of tightly-connected spherical crystal.The 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

Effect of Ga Addition on Catalytic Performance of PtSnNa/ZSM-5 Catalyst for Propane Dehydrogenation

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china Petroleum Processing & Petrochemical Technology 2011年第4期13卷 45-52页

作者： Liu Xuan Zhou Yuming Zhang Yiwei Duan Yongzheng Xue Mengwei Wan Lihui (School of chemistry and chemical engineering, southeast university, nanjing 211189) School of chemistry and chemical engineering Southeast University Nanjing 211189 China

PtSnNaGa/ZSM-5 catalysts with different contents of Ga were prepared and characterized by X-ray diffraction (XRD), nitrogen adsorption, hydrogen chemisorption, ammonia temperature-programmed desorption (NH3-TPD), hydrogen temperature-programmed reduction (H2-TPR), and temperature-programmed oxidation (TPO) techniques. The performances of these catalysts for propane dehydrogenation were investigated. The test results indicated that the addition of Ga not only could improve the catalytic stability and propene selectivity, but also could effectively prevent the catalysts from coking. It was found that the PtSnNaGa(0.5 m%)/ZSM-5 catalyst exhibited the best performance in terms of propene selectivity and propane conversion. The high catalytic performance was most probably attributed to the presence of Ga that could strength- en the interaction between metals and the support to stabilize the catalytic active sites.

关键词：脱氢催化剂丙烷脱氢催化性能 ZSM-5催化剂 NH3-TPD 程序升温脱附程序升温还原程序升温氧化

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 Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing China Key Laboratory of Analytical chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing China National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and therapy.Organic fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of analytes.The photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching occurs.Inorganic nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and compositions.The potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this problem.Surface 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

Inhibitory effect of picroside Ⅱ on hepatocyte apoptosis

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Acta Pharmacologica Sinica 2005年第6期26卷 729-736页

作者： Hua GAO, Ya-wei ZHOU~2 college of chemistry and Molecular engineering, Peking university, Beijing 100871, china college of chemistry and Molecular engineering Peking University Beijing China

Aim: To investigate the influence of picroside on hepatocyte apoptosis and its mechanism. Methods: Morphological changes and quantification of apoptotic cells were determined under transmission electron microscopy and flow cytometry respectively. DNA fragmentation was visualized by agarose gel electrophoresis. Semi-quantitative reverse transcription-PCR (RT-PCR) was used to analyze the expression of bcl-2 and bax genes. The content of manganese-superoxide dismutase (SOD) in liver mitochondria was detected by the Marland method. The content of malonic aldehyde (MDA) and the protein level in liver tissue were determined by thiobarbituric acid colorimetry and Lowry method. Results: Picroside decreased the levels of alanine aminotransferase and aspartate aminotransferase in the serum resulting from acute-liver injured mice induced with D-GalN and LPS; it also reduced the content of MDA, and thus, enhanced the activity of SOD. Picroside 0 mg/kg was found to protect hepatocytes against apoptosis in a dose-dependent manner; it up-regulated the expression of bcl-2 genes, thus increased the bcl-2/bax ratio. Conclusion: Picroside 鈪an protect hepatocytes against injury and prevent hepatocytes from apoptosis. It might by upregulating the bcl-2 gene expression and antioxidation.

关键词： picroside Ⅱ hepatocytes apoptosis oxidative stress bcl-2 genes bax genes

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 State Key Laboratory of Millimeter Waves School of Electronic Science and engineering Southeast University Nanjing China School of chemistry and chemical engineering Nanjing University Nanjing 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 plasma.Furthermore,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 experiments.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 high.Optical emission spectroscopy(OES) was adopted for the diagnosis of methane coupling to acetylene under microwave plasma.The excited species(CH,C2,H2,Hα) were detected in the spectra range of 300-750 nm.Based 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

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) college of chemistry and chemical engineering Nanjing University of Technology Nanjing 210009 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 (NH 3-TPD),FT-IR,and N 2-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：分子筛催化剂四氢制备异构化催化剂催化性能反应温度 TCD X射线衍射