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chemical Research in Chinese Universities 2012年第1期28卷 108-113页

作者： SUN Yang1, HUANG Da-wei1, LI Xiao-hui1, HU Jian-en2.and XIU Zhi-long1 1. school of Life Science and Biotechnology, Dalian university of Technology, Dalian 11602., P. R.{2. 2. school of Food engineering, Dalian Ocean university, Dalian 11602., P. R.{2. Dalian Univ Technol Sch Life Sci & Biotechnol Dalian 116024 Peoples R China Dalian Ocean Univ Sch Food Engn Dalian 116023 Peoples R China

Short peptides based on the tripeptides, Leu-Arg-Pro and Leu-Lys-Pro, were synthesized by microwave assisted solid-phase synthesis method, in order to make a search for potential inhibitors for angiotensin I-converting enzyme（ACE） with minimum side effects in the treatment of hypertension. One peptide with the sequence Leu-Arg-Pro-Phe-Phe shows the strongest inhibition towards ACE with an IC50 value of 0.2. μmol/L in vitro. The study of structure-activity relationship shows that the introduction of a bulky group into the N-terminal of this series of inhibitors may enlarge steric hindrance, resulting in the poor inhibitory activity towards ACE. The inhibitory activity decreased in turn when L-Pro, D-Pro or Ac6c was at the C-terminal respectively. The binding interaction between each of these inhibitors and testicular ACE（tACE） was performed by molecular docking. The results suggest that Leu-Arg-Pro-Phe-Phe mainly occupied the S1 subsite of tACE, and made contact with tACE via seven H-bonds. It appeared that the site on the peptide that bound with tACE was influenced by the configuration of the amino acid, L or D-form, at the C-terminal of the peptide.

关键词： Angiotensin I-converting enzyme Peptide inhibitor Molecular docking Microwave-assisted solid-phasesynthesis

Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 146-149页

作者：霍凯成 Hubei Key Laboratory of Roadway Bridge & Structure engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

Effect of non-cyanide zincation process parameters on the microstructure of the zincation layer on A356 alloys

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Rare Metals 2007年第S1期26卷 313-317页

作者： ZHU Zhaojun1),and HUANG Xiaomei2.1) school of Materials Science and engineering,Harbin Institute of Techmology,Harbin 150001,{2. 2. College of Materials Science and chemical engineering,Harbin engineering university,Harbin 150001,{2. Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Harbin Engn Univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

The effects of non-cyanide zincation process parameters on the microstructure of the zincation layer on A356 alloy were investigated by scanning electronic *** the increasing of zincation time,the zinc grain size and the number density increase gradually,and the zinc grains adhere each *** zinc grain obtained in the double-dipping process is finer,compacter and more homogeneous than that obtained in the single-dipping *** the increasing of the zincation temperature,the morphology of zinc grains changes from spherical shape to flake-like ***,higher zincation temperature results in the flaking off of the zincation layer from the *** optimized zincation temperature is 2.-30 ℃.The quality of the zincation layer obtained in a low concentration,non-cyanide and multi-element zincation solutions is much better than these obtained in conventional high concentration zincation solution,dilute zincation solutions or a dilute zincation solution containing *** addition,the matrix alloy and the pre-treatment also have significant influence on the morphology of the zincation layer.

关键词： non-cyanide zincation solution zincation time zincation temperature morphology

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3,LI Aimin1,3,CAI Jianguo1,3,MENG Guanhua1,3 & ZHANG Quanxing1,3 1. State Key Laboratory of Pollution Control and Resource Reuse,school of the Environment,Nanjing university,Nanjing 2.0093,{2. 2. Nanjing College of chemical Technology,Nanjing 2.0048,{2. 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse,Nanjing 2.0038,{2. 1. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing College of chemical Technology Nanjing 210048 China 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 38# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

Vanadium Carbide Coating Growth on Die Steel Substrate in Borax Salt Bath

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Journal of Wuhan university of Technology(Materials Science) 2010年第4期25卷 600-603页

作者：王洪福 school of Materials Science and engineering Wuhan University of Technology school of Mechanical engineering and Automation North University of China

Vanadium pentoxide, borax, boron carbide and sodium fluoride were used to grow vanadium carbide coating on die steel（Cr12. Cr12.oV） surface at 950 ℃ by TD process, which extended the life period of Cr12.and Cr12.oV as punching die. Kinetics of vanadium carbide coating growth was brought forward and verified by comparison of the mathematical model with the experimental results. The thickness of coating was illustrated by SEM. The chemical constituent of coating and remnants were tested by XRD. To increase the thickness, rare earths （FeSiRe2.） were added to the borax salt bath. The electronic probe microanalysis （EPMA） revealed that the addition of rare earths could decrease carbon concentration in the coating and increase the depth of vanadium carbide coating.

关键词： vanadium carbide coating TD process punching die rare earths

Synthesis and Conductivity of Undecatungstocobaltoruthenic Polyoxometallic Acid

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chemical Research in Chinese Universities 2012年第1期28卷 1-3页

作者： XU Sheng-xian1,2. WU Qing-yin2.and YAN Wen-fu3 1. school of Chemistry and chemical {2., Jiangxi Science & Technology Normal university, Nanchang 330013, P. R. china 2. Department of Chemistry, Zhejiang university, Hangzhou 31002., P. R. china 3. State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin university, Changchun 130012. P. R. china Zhejiang Univ Dept Chem Hangzhou 310027 Zhejiang Peoples R China Jiangxi Sci & Technol Normal Univ Sch Chem & Chem Engn Nanchang 330013 Peoples R China Jilin Univ State Key Lab Inorgan Synth & Preparat Chem Changchun 130012 Peoples R China

Undecatungstocobaltoruthenic polyoxometallic acid H7[Ru（H2.）CoW11O39] 2.H2. was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion ex changing-cooling method. The optimal proportion of the component compound and the pH of the synthesis reaction were given. The product was characterized by means of inductively coupled plasma（ICP）, IR, UV and thermal analy sis. The IR and UV results indicate that H7[Ru（H2.）CoW11O39] 2.H2. possesses the Keggin structure. The results of AC impedance measurement show that its proton conductivity is 2.30×10-3 S/cm at room temperature（2.5 K） and a relative humidity of 75%.

关键词： Polyoxometallic acid Keggin structure Conductivity Ruthenium

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 2.1003,china 2.{2. of Chemistry and chemical engineering,Nanjing university,Nanjing 2.0093,china 3 State Key Lab of Coordination Chemistry,Nanjing university,Nanjing 2.0093,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

Process optimization of reaction of acid leaching residue of asbestos tailing and sodium hydroxide aqueous solution

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Science china(Technological Sciences) 2009年第1期52卷 204-209页

作者： DU GaoXiang1,3, ZHENG ShuiLin2.& DING Hao1 1 school of Materials Science and Technology, china {2. of Geosciences (Beijing), Beijing, 100083, china 2.school of chemical and Environment engineering, china {2. of Mining and Technology (Beijing), Beijing 100083, china 3 Hebei Qinghe Refractory Group Co. Ltd., Xingtai 054804, china 1. school of Materials Science and Technology China University of Geosciences (Beijing) Beijing 100083 China 3. Hebei Qinghe Refractory Group Co. Ltd. Xingtai 054804 China 2. school of chemical and Environment {2. China University of Mining and Technology (Beijing) Beijing 100083 China

Silica is the major component of the acid leaching residue of asbestos tailing. The waterglass solution can be prepared by the reaction of the residue with sodium hydroxide aqueous solution. Compared to the high temperature reaction method, this process is environmental friendly and low cost. In this paper, the reaction process of the residue and the sodium hydroxide aqueous solution is optimized. The optimum reaction process parameters are as follows: the usage of sodium hydroxide is 2..4 g/100 g acid leaching residue, the reaction temperature is 90℃, the reaction time is 1 h, and the ratio of the liquid/solid is 2.0. The significance sequence of the process parameters to the alkali leaching reaction effect is the usage of sodium hydroxide > the ratio of the liquid/solid > the reaction time > the reaction temperature. The significance sequence to the leaching ratio of SiO2.is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. The significance sequence to the modulus of the sodium silicate is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. Under the optimum conditions, the leaching ratio of the SiO2.is 77.5%, and the modulus of the sodium silicate is 3.15. The XRD analysis result indicates that the major components of the alkali leaching residue are serpentine, talc, quartz and some albite.

关键词： asbestos tailing acid leaching residue sodium hydroxide process optimization

Synthesis and Photocatalytic Property of the ZrO_2.TiO_2.Pillared Laponite

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Journal of Wuhan university of Technology(Materials Science) 2011年第5期26卷 852-856页

作者：林英光 College of Materials Science and engineering South China University of Technology

The ZrO2.TiO2.pillared laponite （Ti-Zr-lap） photocatalysts were prepared with intercalation reaction by supercritical fluid drying （SCFD）,and characterized by XRD,TEM,SEM and BET surface area analysis,and the photocatalytic properties of Ti-Zr-lap were investigated by degradation of azo dye acid red B （ARB）.The results showed that the ZrO2.TiO2.pillared structures in laponite could be formed,with the mass fraction of （Zr4＋＋Ti4＋）/laponite （Xm） increasing,the basal spacing and the BET surface area of Ti-Zr-lap significantly *** Ti-Zr-lap used as photocatalyst had the advantages of stable and porous layered structure,large surface area with the anatase type *** with the Ti-Zr-lap dried by air drying,the Ti-Zr-lap dried by SCFD showed better photocatalytic property which was very close to that of P2. *** the Ti-Zr-lap as photocatalyst with the optimum Xm of 0.16 and the calcination temperature of 500 ℃,under the conditions of the initial concentration of ARB 2. mg/L,photocatalyst concentration of 1.5 g/L and irradiation time 60 min,the decoloring rate of ARB could achieve 98.3%,indicating that the Ti-Zr-lap had excellent photocatalytic property.

关键词： ZrO2.TiO2.pillared laponite photocatalytic property intercalation reaction supercritical fluid drying

Influence of Calcination Temperature on TiO_2.Nanotubes’Catalysis for TiO_2.UV/O_3 in Landfill Leachate Solution

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Transactions of Tianjin university 2010年第3期16卷 179-186页

作者：潘留明季民王秀朵赵乐军 school of Environmental Science and engineering Tianjin University Tianjin Municipal engineering Design and Research Institute

The influence of calcination temperature on TiO2.nanotubes＇ catalysis for TiO2.UV/03 was investigated. TiO2.nanotubes （TNTs） were prepared via the sol-gel method and calcined at 300--700 ℃, which were labeled as TNTs-300, TNTs-400, TNTs-500, TNTs-600 and TNTs-700, respectively. TNTs were characterized by transmission electron microscopy （TEM） and X-ray diffraction （XRD）. It is found that TNTs calcined at 400 ℃ showed the best thermal stability. When the calcination temperature increased from 400 ℃ to 700 ℃, the special structure of tubes was destroyed and gradually converted into nanorods and/or particles. The transformation from anatase to rutile occurred at 600 ℃, and the rutile phase was enhanced when the calcination temperature was increased to over 600 ℃. The calcina- tion temperature＇s influence on TNTs＇ adsorption activity for for TiO2.UV/O3 was investigated in landfill leachate solution chemical oxygen demand （COD） and catalytic activity In landfill leachate solution, the adsorption activity of COD decreased in the reduced order of TNTs-300, TNTs-400, TNTs-500, TNTs-600 and TNTs-700. In photocatalytic ozonation, TNTs-400 showed the best catalytic activity while TNTs-700 exhibited the worst. In other three processes, the COD removal of TNTs-300/UV/O3 was higher than those of TNTs-500/UV/O3 and TNTs-600/UV/O3 in the first 2. rain, and then became close to those of the latter two in the following 40 rain. Compared with TNTs-300 and TNTs- 400, TNTs-600 had the best anti-fouling activity, while TNTs-500 and TNTs-700 had lower anti-fouling activity than the former three. In photocatalytic ozonation, the calcination temperature of 400 ℃ was appropriate when TNTs were obtained at the synthesis temperature of 105 ℃.

关键词： TiO2.nanotubes calcination temperature photocatalytic ozonation landfill leachate