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Chinese Chemical Letters 2011年第2期22卷 245-248页

作者： Xiao Jun Dai Yuan He yin mao wei Bo Lin Gong Key Laboratory of Synthetic and Natural Function Molecule Chemistry of Ministry of Education College of Chemistry & Material Science Northwest University Xi'an 710069 China Key Laboratory of Energy & Chemical Engineering Ningxia University Yinchuan 750021 China Received 4 June 2010

A one-step procedure to hydrophilize monodisperse poly（chloromethyl-styrene-co-divinylbenzene） beads has been presented with 2-hydroxy-3-[4-（hydroxymethyl）-1H-1,2,3-triazol-1-yl]propy1 2-methylacrylate（HTMA） as monomer by surface-initiated atom transfer radical polymerization（SI-ATRP）.The length of the grafted poly（HTMA） chain was varied via controlling the ratio of HTMA to initiator on the surface of the *** these grafted beads as the stationary phase in hydrophilic interaction chromatography,good separation was obtained for nucleosides in the mobile phase of *** was also found that the retention time and selectivity of solutes showed a positive relationship with the length of the grafted poly（HTMA） chain.

关键词： Hydrophilic interaction chromatography Polystyrene-based beads Surface-initiated atom transfer radical polymerization 1,2,3-Triazole

Phenylboronic acid and dopamine as probe set for electrochemical detection of saccharides

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Chinese Chemical Letters 2013年第4期24卷 291-294页

作者： Jian Li Ya-Qin Sun yin-mao wei Jian-Bin Zheng Institute of Analytical Science/Shaanxi Key Laboratory of Electroanalytical Chemistry Northwest University

A novel electrochemical approach for detection of saccharides via indicator displacement assay was presented. In this system, 2-fluorophenylboronic acid and dopamine （DA） were performed as probe set. The electrochemical properties of DA and the binding to 2-fluorophenylboronic acid in phosphate buffer at different pH values were investigated by cyclic voltammetry. After addition of fructose to the solution, a competition for the binding 2-fluorophenylboronic acid occurred that led to the release of the DA. The regenerate oxidation current of DA increased with increasing fructose concentration. Under optimized experimental conditions, the peak current was linearly related to fructose concentration in the range of 0.3-5.0 mmol[L with a detection limit of 0.1 mmolJL In addition, the interaction between 2- fluorophenylboronic acid and other cis-diol compounds such as glucose, galactose and mannose was investigated.

关键词： ElectrochemistrySaccharidesDopaminePhenylboronic acidIndicator displacement assay

Synthesis and Characterization of the Tetrazole Analogues of α-Amino Acids

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Chinese Chemical Letters 2006年第12期17卷 1537-1539页

作者： Yah Min HUO Gen Hu LEI yin mao wei Xiao Hui ZHENG Department of Chemistry Northwest University Xi＇an 710069 Research and Engineering Center of Mocternization of Chinese Medicine Northwest University Xi＇ an 710069

The tetrazole analogues have been synthesized from fluorenylmethoxycarbonyl （Fmoc）- protected amino acids by three steps. The structures of the analogues were characterized by HPLC-MS, ^1H NMR and ^13C NMR.

关键词： Synthesis tetrazole amino acid.

Synthesis of Monodisperse Poly(chloromethylstyrene divinylbenzene)Particle and Its Applications

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Chinese Chemical Letters 1998年第11期9卷 0-0,0-0页

作者： yin mao wei Xin Du GENG (Institute of Modern Separation Science, Key Laboratory of Modern Separation Science in Shaanxi Province, Northwest University, Xi’an 710069) NW Univ Xian Inst Modern Separat Sci Key Lab Modern Separat Sci Shaanxi Prov Xian 710069 Peoples R China

Monodisperse poly (chloromethylstyrene divinylbenzene) particles were prepared by a two-step swelling method. It was demonstrated that the packings have comparative advantages for biopolymer separation with high column efficiency, low interstitial volume and low back pressure to the packings prepared with suspension polymerization method. Using size exclusionchromatography and weak ion exchange chromatography as examples, it was shown that these packings could be modified chemically more easily than poly (styrene divinylbenzene) packings.

关键词： Monodisperse poly (chloromethylstyrene divinylbenzene) particles synthesis size exclusion chromatography weak cation exchange chromatography rotein separation

Isoentropic and Isoenthalpic Temperatures of Protein Unfolding in Hydrophobic Interaction Chromatography

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Chinese Chemical Letters 2006年第1期17卷 105-108页

作者： Yah YAN Rui Xian LIU yin mao wei Ye Hua SHEN Xin Du GENG Institute of Modern Separation Science Northwest University Xi＇an 710069 Contemporary Educational Technology Center Northwest University Xi＇an 710069

The thermal behaviors of five proteins in hydrophobic interaction chromatography （HIC） were investigated in the temperature range from 0 to 50℃. The thermodynamic parameters （△H°,△S°, △Cp°and △G°） of these proteins in the process of retention and unfolding were determined. The existence of enthalpy and entropy convergence with temperature was confirmed. The differences of the isoentropic and isoenthalpic temperatures for protein unfolding in HIC system from the traditional solution were elucidated.

关键词： Column liquid chromatography hydrophobic interaction chromatography protein unfolding thermodynamic convergence.

A covalent modified hydrophilic capillary for enhanced capillary electrophoresis of biopolymers

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Chinese Chemical Letters 2009年第9期20卷 1123-1126页

作者： Lian Guo Shan Xue Yu yin mao wei Xiao Hui Zheng Jian Bin Zheng College of Chemistry and Materials Science Northwest University Xi'an 710069 China Institute of Analytical Science Northwest University Xi'an 710069 China

8-Gluconolactone was covalently coupled to aminopropyl derivatized capillary, which created hydrophilic brushes on the inner wall of the capillary. The coated capillary was shown to generate a stable electroosmotic flow （EOF） in the investigated pH range of 2.0-9.0 and to suppress effectively the adsorption of proteins. And it enabled separation of some biopolymer mixtures including basic proteins, DNA and tryptic digested bovine serum albumin （BSA） within 15 rain with efficiencies up to 450,000 plates/m. The intra- and inter-day reproducibility of the coating referring to the retention times of proteins were satisfactory with mean relative standard deviations （R.S.D.） of 0.8 and 1.7%, respectively. 2009 yin mao wei. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Capillary electrophoresis Capillary coating 8-Gluconolactone Protein separation

A Novel Method for Diminishing Protein Aggregation during Denatuaration Process

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Chinese Chemical Letters 2006年第3期17卷 395-398页

作者： Ye Hua SHEN Quan BAI Yang Jun ZHANG yin mao wei Hai Bo WANG Xing Du GENG Institute of Modern Separation Science The Key Lab of Modem Separation Science in Shaanxi Province Northwest University Xi＇an 710069

The addition of packing material for high performance hydrophobic interaction chromatograghy （HPHIC） into the denaturant solution to prevent, or depress protein aggregation in the denatuaration process is presented. The renaturation of α-chymotrypsin （α-Chy） denatured with guanidine hydrochloride （GuHCl） solution indicated that renaturation efficiency can be enhanced from 36.1% to 59.0% by this new method. The structure of the ligand linking of HPHIC packings is also important for the protein renaturation.

关键词： Protein renaturation α-chymotrypsin hydrophobic interaction chromatography

High Performance Hydrophobic Interaction Chromatography-A New Approach to Separate Intermediates of Protein Folding──Ⅰ.Separation of Intermediates of Urea-unfolded α-Amylase

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Chinese Chemical Letters 1997年第1期8卷 67-70页

作者： Quan BAI yin mao wei Ming Hui GENG Xin Du GENG(Institute of Modern Separation Science Northwest University Xi’an, 710069) Inst. of Modern Separation Science Northwest University Xi'an 710069 China Department of Chemistry Purdue University West Lafayette IN 47907 United States

Based on the different hydrophobicities of the intermediates of proteins the various conformational intermediates of the refolding of a-amylase originally denatured with 8.0 mol/L urea solution were separated with high performance hydrophobic interaction chromatography(HPHIC). Compared to the separation of the same intermediates with weak anion exchange chromatography and size-exclusion chromatography the result obtained with HPHIC is the best It would be expected that HPHIC may be a strongly potential tool to separate intermediates of some proteins which cannot be, or cannot completely be refolded by HPHIC.

关键词： Separation of Intermediates of Urea-unfolded OC High Performance Hydrophobic Interaction Chromatography-A New Approach to Separate Intermediates of Protein Folding Amylase

Poly [ (chloromethyl) styrene-co-divinylbenzene] Continuous Rod Column of Weak Cation Exchange Chromatography and its Applications in the Separation of Biopolymers

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Chinese Chemical Letters 1999年第3期10卷 215-218页

作者： Quan Zhou LUO yin mao wei Tong LIU Gen Hu LEI Xin Du GENG(Institute of Modem Separation Science. Shaanxi Provincial Key Laboratory of Modem SeparationScience. Northwest University. Xi’an 710069) Northwest Univ Inst Modern Separat Sci Shaanxi Prov Key Lab Modern Separat Sci Xian 710069 Peoples R China

Macroporous poly [(chloromethyl) styrene-co-divinylbenzene] continuous rod was prepared by direct polymerization of the monomers in the presence of a porogenic diluent inside an empty chromatographic column. A new 'in-situ' technique was used to modify the synthesized polymer rod for a weak cation exchanger and it has been used successfully for the separation of biopolymers. It was found that the back pressure of the continuous rod column was much lower and its surface was proved to be modified well.

关键词： liquid chromatography weak cation exchange polymer continuous rod modification biopolymer separation

400MHz 12bit TIADC电路设计与误差校正

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电子技术应用 2008年第12期34卷 64-66,78页

作者：印茂伟西南科技大学国防科技学院四川绵阳621010

时域交错模数转换(TIADC)是目前高速高分辨率 ADC 设计的一种有效方案。通过一个400MHz 12bit ADC 的 PCB 设计,阐述了 TIADC 设计中的一些普遍问题,在误差分析的基础上给出一种硬软件综合校正方法。实测结果表明了设计的有效性。

关键词：时域交错模数转换通道失配 Gram-Schmidt正交化误差校正有效数据位数