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CORROSION MONITORING OF LY12 IN SODIUM CHLORIDE SOLUTION WITH ELECTROCHEMICAL NOISE TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 91-96页

作者： J.Q. Zhang, Z. Zhang, J.M. Wang, H.B. Shao and C.N. Cao (Department of chemistry, Zhejiang University , Hangzhou 310027, China) (State Key Laboratory for Corrosion and Protection of Metals, Institute of Metal Research, The Chinese Academy of Sciences, She dept. of Chem. Zhejiang Univ. Hangzhou 310027 China

Spontaneous electrochemical noise (EN) can be a rich source of information concerning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the complicated nature of the specific systems being investigated. In this paper, the potential noise fluctuations during the free corrosion of commercial aluminum alloy LY12 in sodium chloride solution was recorded and analyzed with different techniques. The typical results showed that the fractal dimension (D,n) obtained from spectral power density (SPD) is mainly directly proportional to the intensity of pitting corrosion and to the value of pitting parameter (SE) derived from dimensional analysis, while the fractal dimension (DE) obtained from EIS is mainly related to the uniform corrosion.

关键词： electrochemical noise fractal stochastic analysis dimensionanalysis localized corrosion

Synthesis of Z and E-(2',5'-dimethoxyphenyl)-methylene-butyrolactones

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Chinese Chemical Letters 2000年第2期11卷 109-110页

作者： Yong Ying JIANG2 Zhi Yun LIN Li Ya ZHU1 (1dept. Of medicinal chemistry, College of pharmacy, Rutgers University, Piscataway, NJ, U.S.A. Institute of Materia Medica, Peking Union Medical College and) Chinese Academy of Medical Sciences, Beijing 100050 Institute of Materia Medica Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100050 China dept. of Medicinal chemistry College of Pharmacy Rutgers University Piscataway NJ United States

A pair of Z and E isomers of cyclization of γ-ketoacid 7, which was prepared in six steps from 2,5-dimethoxyphenyl acetic acid 1, gave a pair of Z(20%) and E (4%) isomers of (2,5-dimethoxyphenyl)-methylene-butyrolact... 详细信息

关键词： Butyrolactone γ-keto-acid lactonization ferric sulfate hydrate.

EIS STUDY ON ZINC RICH PAINTS IN 3.5% NaCl SOLUTION BY DOUBLE-CELL TEST

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 299-306页

作者： DM. Xie, J.M. Hu, J.M. Wang and J.Q. ZhangDepartment of chemistry, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory for Corrosion and Protection of Metals, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China dept. of Chem. Zhejiang Univ. Hangzhou 310027 China

This paper discussed the possibility of obtaining electrochemical impedance spectroscopy (EIS) responses of zinc rich paints (ZRP) using serial double-cell (SDC). The influence of counter electrode was outlined. An equivalent circuit (ES) for the double-cell was then discussed. The relationship between EC, the time constant, the parameters in EC of SDC and those of two single sells was discussed. The results gained by serial double cell test are consistent with those of single cell test. It can be concluded that double cell test method can be used to study ZRP completely.

关键词： Electrodes Equivalent circuits Sodium chloride Spectroscopy Zinc

Preparation and Spectroscopic of Vanadyl（Ⅱ） Vitamin D3 Amino Acid Mixed Complexes as Insulin Mimetic Drug

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光谱学与光谱分析 2019年第7期39卷 2316-2324页

作者： Enas Aljuhani Amnah M.A.Alsuhaibani A.M.El-Di damony N.Hassan Sameh Abo Taleb Moamen S.Refat Department of chemistry Faculty of Applied ScienceUmm Al-Qura UniversityMakkahP.O.9168 Zip Code 21955Saudi Arabia Nutrition and Food Sciences dept. Home Economic CollegePrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia Department of chemistry Faculty of ScienceZagazig UniversityEgypt Department of chemistry Faculty of SciencePort SaidPort Said UniversityEgypt chemistry Department Faculty of ScienceTaif UniversityP.O.Box 888Al-HawiahTaif 21974Saudi Arabia

A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthesized by the chemical reactions between vitamin D3(VD3), VOSO4 and amino acids(AAn) with equal molar ratio 1∶1∶1 in neutralized media. The structures of these complexes were elucidated by spectroscopic methods like, infrared and solid reflectance spectroscopes. Magnetic moments and electronic spectra reveal square pyramid geometrical structure of the complexes. The infrared spectra assignments of these complexes revealed that the chelation towards vanadyl(Ⅳ) ions existed via deprotonation of the hydroxyl group of VD3 drug ligand and so amino acids act as bidentate ligand via N-amino and O-carboxylate groups. The anti-diabetic efficiency of these complexes were evaluated against streptozotocin induced diabetic male albino rats.

关键词： Insulin alternative Diabetes Drug VO^2+ ion Vitamin D3 Amino acid Spectroscopic

The Simultaneous Determination of Cu Ph Cd and Sb by Derivative Adsorption Chronopotentiometry

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Chinese Chemical Letters 2000年第9期11卷 807-808页

作者： Xiao Li ZHANG Shu Ying PAN Department of chemistry Shandong University, Jinan 250100 dept. of Chem. Shandong University Jinan 250100 China

The behaviour of the complexes of copper,lead,cadmium and antimony with salicylfluorone (SAF) adsorbed on HMDE has been investigated by derivative chronopotentiometry in NH_3/NH_4C1. The dependence of the peak height on the dt/dE vs E curve on preconcentration time, the pH of solution and the constant reducing current are discussed. This method achieved the simultaneous determination of copper, lead, cadmium and antimony in human hair.

关键词： Simultaneous determination Cu,Pb,Cd,Sb complex chronopotentiometry.

ELECTROCHEMICAL NOISE ANALYSIS OF PURE ALUMINUM IN SODIUM CHLORIDE SOLUTION WITH WAVELET TRANSFORM TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 272-278页

作者： Z. Zhang, Q.D. Zhong, J.Q. Zhang, Y.L. Cheng, F.H. Cao, J.M. and C.N. CaoDepartment of chemistry, Zhejiang University, Hangzhou 310027, ChinaElectrochemical Research Group, Shanghai University of Electric Power, Shanghai 200090, ChinaState Key Laboratory dept. of Chem. Zhejiang Univ. Hangzhou 310037 China

Wavelet transforms (WT) are proposed as an alternative tool to overcome the limitations of Fourier transforms (FFT) in the analysis of electrochemical noise (EN) data. The most relevant feature of this method of analysis is its capability of decomposing electrochemical noise records into different sets of wavelet coefficients, which contain information about the time scale characteristic of the associated corrosion event. In this context, the potential noise fluctuations during the free corrosion of pure aluminum in sodium chloride solution was recorded and analyzed with wavelet transform technique. The typical results showed that the EN signal is composed of distinct type of events, which can be classified according to their scales, i.e. their time constants. Meanwhile, the energy distribution plot (EDP) can be used as 'fingerprints' of EN signals and can be very useful for analyzing EN data in the future.

关键词： electrochemical noise wavelet analysis Fourier transforms corrosion pure aluminum

Three-dimensional configurations of organic/inorganic hybrid nanostructural blocks (I).A quantum mechanical investigation for ladder-like structure of vinylsilsesquioxane

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Science China chemistry 2004年第5期47卷 388-395页

作者： ZHANG Xingwen1,2, HU Lijiang1, HUANG Yudong1, SUN Dezhi2 & SUN Yi3 1. Department of Applied chemistry,Harbin Institute of Technology, HUANG Yudong, Harbin 150001, China 2. Department of Environmental Engineering, Harbin Institute of Technology, Harbin 150001, China 3. Department of Experimental Mechanics,Harbin Institute of Technology, Harbin 150001, China dept. of Applied Chem. Harbin Inst. of Technol. Harbin 150001 China dept. of Environ. Eng. Harbin Inst. of Technol. Harbin 150001 China dept. of Experimental Mech. Harbin Inst. of Technol. Harbin 150001 China

The organic/inorganic hybrid nanostructural vinylsilsesquioxanes (VSSO) were prepared from the hydrolytic condensation of vinyltrimethoxysilane (VMS). The proposed formu- las of VSSO were assigned with standard spectroscopic techniques, FTIR, NMR (1H, C and 13 29Si) and MALDI-TOF MS, and a generic formula of the SSO, Tn(OH)x(OR’)y(x, y = 0, 1, 2…; n = 1, 2…; T = RSiO1.5 ?(x+y)/2n). Geometric parameters (Si-O and Si-C bond lengths, Si-O-Si and O-Si-O bond angles) and total energies of the multi-structures of VSSO were calculated by a quantum mechanical investigation and molecular symmetries. According to the results of the calculation, most molecules had stabler ladder structures than the cage isomers, therefore, the most probably reasonable and optimum structure of the VSSO system was the ladder type.

关键词： vinyltrimethoxysilane (VMS), silsesquioxanes (SSO), sol-gel process, quantum mechanical calculation, MNDO.

Oxygen Permeability of Polypropylene Containing Polyisobutene with Magnesium Acetate

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 118-121页

作者： Wei Tian Raymond T. Woodhams(Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China)(dept. of Chemical Engineering and Applied chemistry, University of Toronto, Torono M5S IA4, Canada) Material Science and Engineering School University of Science and Technology Beijing Beijing 100083 China dept. of Chemical Engineering and Applied chemistry University of Toronto Toronto Ont. M5S IA4 Canada

The oxygen permeabilities of polypropylene films are reduced by adding a minor percentage of a polyisobutene ionomer. The polyisobutene ionomers were prepared by in situ salt exchange of magnesium acetate with maleated polyisobutenes of commercially available low relative molecular mass. The more polar magnesiurn salts aided phase separaion during crystallization from the molten polypropylene mixtusre. Scanning electron microscope photographs revealed that the polyisobotene ionomer is largely concentratd in the amorphous regions between the polypropylene spherulites, where the ionomer tends to concentrate during crystallization. The influence of the polyisobutene ionomer on the oxygen permeability of polypropylene was found to be slightly dependent upon the relative molecular mass of the polyisobutene precursor. Under optimum conditions, the oxygen permeability of polypropylene is reduced by 20%with only 1% additive.

关键词： oxygen permeability polypropylene polyisobutene

Estimation of Pore Charge on Zirconia Membrane Prepared by Sol-gel Route Using Zeta Potential Measurement

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Journal of Materials Science & Technology 1998年第5期14卷 425-428页

作者： Seshadri, K.S. Ahmed, Jallel Kesavamoorthy, R. Varatharajan, K. Srinivasan, M.P. Krishnasamy, V. Centralised Waste Management Facility Kalpakkam Tkmil Nadu -603 102 India Material Science Laboratory IGCAR Kalpakkam India Water and Steam chemistry Laboratory IGCAR Kalpakkam India dept. of Chemical Engineering Anna University Chennai India

Zirconia membrane was prepared in the sol-gel process by filtering viscous colloidal zirconia sol through microporous alumina support and gelling followed by sintering at 743 K. The scanning electron micrograph shows that mean pore size is 543 nm and pore density is 1.47 multiplied by 10**7/cm**2. The filtration characteristics during membrane layer formation show that the membrane layer formation starts after 40 min. The membrane layer thickness and the porosity of the membrane were determined gravimetrically by finding out the amount of water present in the pores. The membrane layer thickness was found to be 3 micron and the porosity was found out to be 0.38. The pore charge density was estimated from the particle charge density, pore density, pore diameter and the thickness of the membrane layer. (Edited author abstract) 5 Refs.

关键词： Zirconia