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Science china chemistry 2011年第6期54卷 951-956页

作者： WU Hui, JIN Can, HUANG GuoLi, WANG LianJun, JIANG JuLi & WANG LeYong Key Laboratory of Mesoscopic chemistry of Ministry of Education school of chemistry and chemical engineering, nanjing university, nanjing 210093, china 1. Key Laboratory of Mesoscopic chemistry of Ministry of Education school of chemistry and chemical engineering Nanjing University Nanjing 210093 China

Two new bis-imidazolinium salts (4a, 4b) have been synthesized as precursors of N-heterocyclic carbenes (NHCs) from the commercially available (R)-2,2′-dihydroxy-1,1′-binaphthalene. The two bis-imidazolinium salts were used as efficient precursor of NHC ancillary ligands in the palladium-catalyzed Heck reaction. Good to excellent yields and high stereoselectivities were obtained with ethyl acrylate, acrylonitrile, and acrylamide as starting materials. The structure of bis-imidazolinium salt 4b was further characterized by single crystal X-ray diffraction analysis.

关键词： N-heterocyclic carbenes Heck reaction palladium imidazolinium salts

Hydroisomerization of n-heptane over bimetal-bearing H_3PW_(12)O_(40) catalysts supported on dealuminated USY zeolite

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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 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

Surface Modification of Silk Fibroin Films with Zwitterionic Phosphobetaine to Improve the Hemocompatibility

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Journal of Wuhan university of Technology(Materials Science) 2010年第6期25卷 969-974页

作者：蒋雪峰陈强 school of chemistry and chemical engineering Nanjing University

Zwitterionic phosphobetaine bearing a hydroxyl and a zwitterionic group,8-hydroxy-2-octyl phosphorylcholine（HOPC）,was synthesized and constructed to the surface of silk fibroin（SF） films in order to improve the hemocompatibility of fibroin films by a an isocyanate head *** surface characteristics of the modified films were measured by attenuated total reflection Fourier transform infrared spectroscopy（ATR-FTIR） and electron spectroscopy for chemical analysis（ESCA）,displaying the successful immobilization of Zwitterionic phosphobetaine on the surface of these fibroin ***,the further platelet adhesion test in platelets rich plasma（PRP） of human beings showed the zwitterionic phosphobetaine led mainly to good *** experimental results indicated a reasonable approach to improve the blood compatibility of fibroin films.

关键词： zwitterionic phosphobetaine silk fibroin blood compatibility platelet adhesion

The frequencies of high frequency quasi-periodic oscillations in two different frames in black hole LMXBs

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Research in Astronomy and Astrophysics 2011年第11期11卷 1327-1335页

作者： Chang-Sheng Shi College of Material Science and chemical engineering,Hainan university,Hainan 570228,china Key Laboratory of Modern Astronomy and Astrophysics,nanjing university,nanjing 210093,china College of Material Science and chemical engineering Hainan University Hainan 570228 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Nanjing 210093 China

We discuss the modes of the Alfvén waves in the accretion disk with a toroidal magnetic field in black hole low mass X-ray binaries in a rotating frame. By solving the perturbed general relativistic magnetohydrodynamic equations in the rotating frame, we find two stable modes of the Alfvén wave which are the same as those in the fiducial observer frame. This gives a feasible way to transform between the two different frames, which validates the possible Alfvén wave modes in the accreting celestial bodies with a toroidal magnetic field.

关键词： accretion accretion disks-magnetohydrodynamics-relativity

Rhodamine B doped silica nanoparticle labels for protein microarray detection

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Science china chemistry 2010年第4期53卷 747-751页

作者： WANG Ying1, LI ZhongHui1, ZHONG WenYing2, LI Hui2, XU DanKe1 & CHEN HongYuan1 1Key Laboratory of Analytical chemistry for Life Science, Ministry of Education school of chemistry and chemical engineering, nanjing university, nanjing 210093, china 2Department of Analytical chemistry, china Pharmaceutical university, nanjing 210009, china 1. Key Laboratory of Analytical chemistry for Life Science Ministry of Education school of chemistry and chemical engineering Nanjing University Nanjing 210093 China2. Department of Analytical Chemistry China Pharmaceutical University Nanjing 210009 China

A core-shell Rhodamine B-doped SiO2 nanoparticle was synthesized and its fluorescent intensity was found to be 1000 times higher than that of individual Rhodamine B molecule. The doped nanoparticles were further conjugated with streptavidin and the resulting nanoparticles were used in the detection of reverse-phase protein microarrays, in which human IgG of various concentrations was first immobilized on aldehyde-modified glass slides and then biotinlyated goat anti human IgG as well as the labeled nanoparticles were sequentially conjugated. The calibration curve is linear over the range from 800 fg to 500 pg and the limit of detection is 100 fg, which is 8 times lower than that of streptavidin-labeled Cy3 fluorescent dyes. The dyedoped SiO2 nanoparticles show potentials for the protein array detection.

关键词： Rhodamine B SiO2 nanoparticles protein detection protein microarrays

Fluorescence determination of platinum with dibromohydroxyphenyl-fluorone in microemulsion after separation and enrichment by sulfhydryl dextrose gel

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Rare Metals 2008年第1期27卷 101-105页

作者： LI Huizhi ZHAI Yubo ZHAI Diantang school of chemistry and chemical engineering Jinan University Jinan 250022 China school of Life Science Nanjing University Nanjing 210093 China

A new fluorescence quenching method has been developed for the determination of platinum in nonionic microemulsion *** method is based on the fact that platinum can form a stable chelate with dibromohydroxyphenyl-fluorine（DBHPF） when they are in the molar ratio of 1：2 in the nonionic microemulsion *** optimum conditions,the system,having the maximum excitation and emission wavelengths at 468 nm and 532 nm,respectively,shows constant fluorescence intensity in the pH range of 3.5-4.0 and high selectivity and sensitivity as well as low interference from foreign ***,this fluorescence intensity is a linear function of Pt（IV） concentration in the range of 0.002-1.00 μg·mL^-1 and the limit of detection is 2.90 ng·mL^-1.

关键词： analytical chemistry separation and enrichment fluorescence determination microemulsion platinum(IV)

A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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Science china chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2,ZHONG QingDong2 & LU TianHong3 1Department of chemical engineering,Shanghai Institute of Technology,Shanghai 200233,china 2school of Materials Science and engineering,Shanghai university,Shanghai 200072,china 3Department of chemistry,nanjing Normal university,nanjing 210097,china 1. Department of chemical engineering Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCWC) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPS that Lac was strongly adsorbed on the surface of the MCWC *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.730 × 10-12 mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCWC) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry

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

Molecular dynamics simulation study on zwitterionic structure to maintain the normal conformations of Glutathione

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Science china chemistry 2007年第5期50卷 660-664页

作者： YAN Han1, ZHU HaoMiao2 & SHEN Jian1,2 1 Jiangsu Research Center of Surface and Interface chemical engineering and Technology, nanjing university, nanjing 210093, china 2 Jiangsu engineering Research Center for Bio-medical function Materials, nanjing Normal university, nanjing 210097, china Jiangsu Research Center of Surface and Interface chemical engineering andTechnology Nanjing UniversityNanjing 210093China Jiangsu engineering Research Center forBio-medical function Materials Nanjing Normal UniversityNanjing 210097China

Molecular dynamics simulations were applied to normal conformational Glutathione (GSH) and GSH over zwitterionic and hydrophobic surfaces respectively. Conformational analysis of GSH during the simulation time on RMSD, conformational flexibility and dihedral distribution were performed. The re- sults showed that zwitterionic structure maintains the normal conformations of GSH to a better extent, which should be a first good proof of the hypothesis of "maintain of normal structure".

关键词： protein-surface interactions, molecular dynamics simulation, zwitterionic structure, Glutathione, conformational changes, antithrombotic material

The resonance Rayleigh scattering of the interaction of copper(Ⅱ)-bleomycinA2 with DNA and its analytical application

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Science china chemistry 2010年第3期53卷 618-624页

作者： LIU JiangTao1,LIU ShaoPu2 & LIU ZhongFang2 1school of chemistry,Chongqing Normal university,Chongqing 400300,china 2school of chemistry and chemical engineering,Southwest university,Chongqing 400715,china school of chemistry Chongqing Normal University Chongqing China school of chemistry and chemical engineering Southwest University Chongqing China

The forming of bleomycinA2-Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence *** result shows that in aqueous solution,bleomycinA2(BLMA2) can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of *** the cationic chelate further bound with DNA to form ternary ion-association complexes,the remarkable enhancement of the RRS intensity was *** this work,the optimum conditions for the coordination reaction of BLMA2 with Cu(Ⅱ) and some influencing factors have been *** reaction mechanism of BLMA2-Cu(Ⅱ) binding with DNA was suggested and a binding model was *** addition,the fluorescence quenching type of BLMA2 was investigated.A highly sensitive,simple and rapid new method for the determination of DNA by using BLMA2-Cu(Ⅱ) as RRS probe has been *** detection limits(3σ) are 7.2 ng/mL for ctDNA,7.1 ng/mL for sDNA and 18 ng/mL for *** method can be applied to the determination of trace amounts of DNA.

关键词： bleomycinA2 Cu(Ⅱ) DNA resonance Rayleigh scattering fluorescence quenching