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Improved electrochemical performances of polyaniline nanotubes-poly-L-lysine composite for label-free impedance detection of DNA hybridization

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science china Chemistry 2010年第6期53卷 1371-1377页

作者： YANG Tao,JIANG Chen,ZHANG Wei & JIAO Kui Key Laboratory of Eco-chemical engineering,Ministry of Education college of Chemistry and Molecular engineering,Qingdao university of science and Technology,Qingdao 266042,china Key Laboratory of Eco-chemical engineering Ministry of Education college of Chemistry and Molecular engineering Qingdao University of Science and Technology Qingdao China

A sensitive label-free DNA hybridization biosensing platform was fabricated based on the synergistic effect of polyaniline nanotubes (PANInt) and poly-L-lysine (pLys).The composite of pLys and PANInt was coated onto the carbon paste electrode (CPE) to form a uniform and very stable nanocomposite *** pLys in the composite film not only acts as a membrane to retain good electron transfer capability of PANInt even at physiological pH,but also possesses fine biocompatibility for *** probes with negatively charged phosphate groups were readily linked to the positively charged pLys surface due to the strong electrostatic *** synergistic effect of PANInt and pLys could significantly enhance the sensitivity of DNA hybridization *** phosphinothricin acetyltransferase (PAT) gene fragment from transgenic corn and the polymerase chain reaction amplification of the terminator of nopaline synthase gene from the real sample of a kind of transgenic soybean were detected by this DNA electrochemical biosensor via label-free impedance *** stable composite gives convenient permselectivity properties as a transducer material for the design of modern electrochemical impedance biosensor using [Fe(CN)6]3-/4as an indicator.

关键词： poly-L-lysine polyaniline nanotubes DNA electrochemical biosensor PAT gene NOS gene

New Developed Welding Electrode for Improving the Fatigue Strength of Welded Joints

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Journal of materials science & Technology 2002年第6期18卷 527-531页

作者： Wenxian WANG, Lixing HUO, Yufeng ZHANG, Dongpo WANG and Hongyang JINGcollege of material science and engineering, Tianjin university, Tianjin 300072, china Coll. of Mat. Sci. and Eng. Tianjin Univ. Tianjin 300072 China

A new welding electrode, low transformation temperature electrode (LTTE), was introduced in this paper. It was described in design principle, mechanics, chemical compositions of their deposited metal and manufacturing methods. It was proved that the best transformation starting temperature from austenite to martensite of the deposited metal of LTTE was at about 191℃ and it was obtained by adding alloying elements such as Cr, Ni, Mn and Mo. The microstructure of the weld metal of the LTTE was low carbon martensite and residual austenite. The compressive residual stress was induced around the weld of the LTTE and the -145 MPa in compression could be obtained in middle of weld metal. The fatigue tests showed that the fatigue strength of the longitudinal welded joints welded with the LTTE at 2×106 cycles was improved by 59% compared with that of the same type of welded joints welded with conventional E5015 and the fatigue life was increased by 47 times at 162 MPa. It is a very valuable method to improve the fatigue performance of welded joints.

关键词： Low transformation temperature electrode Compressive residual stress Fatigue strength Welded joints

Colloidal organic carbon in Huanghe, Changjiang and Qiantang River

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Chinese science Bulletin 1998年第11期43卷 915-917页

作者： WANG Jiangtao college of Chemistry and chemical engineering, Ocean university of Qingdao, Qingdao 266003, china Callege of Chemistry and chemical engineering Ocean University of Qingdao Qingdao China

Cross-flow ultrafiltration techniques have been used to separate colloidal organic carbon (COC) from natural water, and COC in three water samples that were collected from Huanghe, Changjiang and Qiantang River was determined. On average, COC comprised about 68.6% of the total dissolved organic carbon. The abundance of COC suggested that COC could play important roles in input fluxes and biogeochemistry of organic carbon.

关键词： cross-flow ultrafiltration colloidal organic carbon.

Theoretical studies of the transport property of oligosilane

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science china Chemistry 2010年第12期53卷 2571-2580页

作者： ZHANG GuiLing 1,YUAN HongLiang 1,ZHANG Hui 1,SHANG Yan 1,SUN Miao 1,LIU Bo 1 & LI ZeSheng 2 1 college of chemical and Environmental engineering,harbin university of science and Technology,harbin 150080,china 2 State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry,Jilin university,Changchun 130023,china college of chemical and Environmental engineering Harbin University of Science and Technology Harbin China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China

The transport mechanisms of four-conjugated systems were comparatively studied by combining ATK and Gaussian 03 *** was found that the charge-doped oligosilane behaved in a different way from the boron doped and phosphorus doped oligosilanes in terms of the transmission *** charge-doped oligosilane showed almost no conductivity owing to the damage of the electron transfer path by *** contrast,the boron doped and phosphorus doped oligosilanes were demonstrated to be good semiconductors and NDR behavior was observed for *** is a reasonable result after the analysis of the transmission spectra,MPSH states,energy gap,conjugation effect,and scattering effect.

关键词： theoretical study transport property oligosilane

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 University Lanzhou China college of Chemistry and chemical engineering Sun Yat-sen University Guangzhou China

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 45.00 kJ/mol. In contract, the reaction barriers for the [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

Synthesis and photochromic properties of WO_3 powder induced by oxalic acid

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science china Chemistry 2009年第5期52卷 609-614页

作者： SHEN Yi1, ZHU Hua1, HUANG Rong1, ZHAO Li2 & YAN ShaNing1 1 Faculty of material science and chemical engineering, china university of Geosciences, Wuhan 430074, china 2 Faculty of materials science and engineering, Hubei university, Wuhan 430062, china Faculty of material science and chemical engineering China University of Geosciences Wuhan China Faculty of materials science and engineering Hubei University Wuhan China

Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up of regularly spindle particles with 200-300 nm in length and 30-50 nm in width. The ratio of the length and width was from 4 to 10. Moreover, the special morphology improved its absorptive capacity to the excitation light source, resulting in its high photochromic properties.

关键词： WO3 powder photochromism oxalic acid organic inducer

Pb(Mg_(1/3)Nb_(2/3))O_3-PbTiO_3-BaTiO_3 Complex Perovskite Ferroelectric Ceramics with High Dielectric Constant and Low Firing Temperature

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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 115-117页

作者： Zhen Ji Zhhong Xiao Xuqing Liu Zhaozeng Ma Zongsen Yu(material science and engineering School, university of science and Technology Bejing, Beijing 100083, china) material science and engineering School University of Science and Technology Beijing Beijing 100083 China

The effects of different firing temperatures on the stability of perovskite phase, grain size, and dielectric properties were investigated by XRD, TEM, SEM and dielectric measurements. The dielectric ceramics of Pb(Mg1/3Nb2/3)O3-PbTiO3-BaTiO3 system were obtained by chemical coprecipitation in water. The ceramics have higher dielectric constant (7003-9714), lower firing temperature(950-1150℃), quite uniform microstructure with grain size less than 2.5 mp, and lower temperature coefficients of capacitance. As a re-sult, it was confirmed that the simple and low cost chemical route used namely coprecipitation in water is a desired method for preparinghigh property dielectfic materials applicable to multilayer capacitors.

关键词： PMN-PT-BT coprecipitation dielectric property

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 *** transfection efficiency of PEI,along with its cytotoxicity,strongly depends on itsmolecular *** enhance its gene delivery efficiency and minimize cytotoxicity,we have synthesizedsmall cross-linked PEI with biodegradable linkages and evaluated their transfection efficiencies in *** 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 *** 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 *** cytometrywas used to quantify the cellular entry efficiency of plasmid and the transgene expression *** of the cross-linked PEI in these cells were evaluated by MTT ***-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 ***,the transfection activity of polyplexes was preserved in thepresence of serum proteins.

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

Effect of Deformation Condition on Axial Compressive Precision Forming Process of Tube with Curling Die

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Journal of materials science & Technology 2001年第1期17卷 135-136页

作者： He YANG and Zhichao SUN college of materials science and engineering, Northwestern Polytechnical university, Xi’an 710072, china Coll. of Mater. Sci. Northwestern Polytechnol. Univ. Xi'an 710072 China

The effect of the deformation condition on the axial compressive precision forming process of tube with curling die was investigated by using a rigid-plastic FEM. The results show that the forming accuracy depends mainly on geometric condition rp/d0, little on tube material properties and friction condition; the relative gap △/2rp of double-walled tubes obtained decreases with Increasing rp/d0, and there is a parameter k for a given to/do or rp/t0, when rp/d0 >k, △/2rp1.

关键词： Effect of Deformation Condition on Axial Compressive Precision Forming Process of Tube with Curling Die