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Separation of Six Pyridoncarboylxic Acid Derivatives by Micellar and Microemulsion Electrokinetic Chromatography

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Chinese Chemical Letters 2001年第2期12卷 155-156页

作者： Jian De LU Wei YUAN xiao yun fu Analytical and Testing Center Yuquan CampusZhejiang UniversityHangzhou 310027

Micellar and microemulsion electrokinetic chromatography (MEKC & MEEKC) separation of six closely structural pyridoncarboylxic acid derivatives were studied and compared Both anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant hexadecyl-trimethyl ammonium bromide: (CTAB) were used to form micellar and microemulsion as pseudostation phases, respectively. The effects of the separation conditions on retention time and selectivity were studied. Good resolutions were obtained in selected systems. indicating that there is markably different selectivity between SDS and CTAB systems.

关键词： Micellar microemulsion electrokinetic chromatography

Study of Oxidation of Glutathione Treated with Hypochlorous Acid by Capillary Electrophoresis

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Chinese Chemical Letters 2001年第7期12卷 623-624页

作者： Xian LUO Jian De LU xiao yun fu Analytical and Testing Center Zhejiang UniversityHangzhou 310027

Capillary electrophoresis (CE) method was developed for the separation and quantification of reduced glutathione (GSH), oxidized glutathione (GSSG) and glutathione sulphonic acid (GSO(3)H). Baseline separation was obtained within five minutes. The effects of reaction time and molar ratio of hypochlorous acid (HOCl) to GSH on the oxidation of GSH were investigated.

关键词： Glutathione oxidation capillary electrophoresis

Asymmetric fuzzy Control of a Positive and Negative Pneumatic Pressure Servo System

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1438-1446页

作者： Gang Yang Jing-Min Du xiao-yun fu Bao-Ren Li School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074China

The pneumatic pressure control systems have been used in some fields. However, the researches on pneumatic pressure control mainly focus on constant pressure regulation. Poor dynamic characteristics and strong nonlinearity of such systems limit its application in the field of pressure tracking control. In order to meet the demand of generating dynamic pressure signal in the application of the hardware-in-the-loop simulation of aerospace engineering, a positive and negative pneumatic pressure servo system is provided to implement dynamic adjustment of sealed chamber pressure. A mathematical model is established with simulation and experiment being implemented afterwards to discuss the characteristics of the system, which shows serious asymmetry in the process of charging and discharging. Based on the analysis of the system dynamics, a fuzzy proportional integral derivative （PID） controller with asymmetric fuzzy compensator is proposed. Different from conventional adjusting mecha- nisms employing the error and change in error of the controlled variable as input parameters, the current cham- ber pressure and charging or discharging state are chosen as inputs of the compensator, which improves adaptability. To verify the effectiveness and performance of the pro- posed controller, the comparison experiments tracking sinusoidal and square wave commands are conducted. Experimental results show that the proposed controller can obtain better dynamic performance and relatively consis- tent control performance across the scope of work （2-140 kPa）. The research proposes a fuzzy control method to overcome asymmetry and enhance adaptability for the positive and negative pneumatic pressure servo system.

关键词： Pneumatic pressure control system Positiveand negative pressure Asymmetric control fuzzy control

Synthesis and hydrosilation of multi-vinyl branched siloxane for self-healing system

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Chinese Chemical Letters 2008年第6期19卷 655-657页

作者： xiao yun fu Zheng Ping Fang Hai Tang Yang Li Fang Tong lnstitute of Polymer Composites Zhejiang University Hangzhou 310027 China Key Laboratory of Macromolecular Synthesis and functionalization （Zhejiang University） Ministry of Education Hangzhou 310027 China

In this work, the preparation of α,ω-dichloride-terminated multi-vinyl branched siloxane 1 （yield： 57.1%） used for self-healing polymer composites were synthesized via ring-opening of 1,3,5,7-tetravinyl-1,3,5,7-tetramethyl-cyclotetrasiloxane （D4^vi） in the presence of vinylmethydichlorosilane （VM-32）. 1 was hydrogenated by aluminum lithium hydride （LiAlH4） to get self-healing monomer 2 （yield： 79.8%） which contained both Si-H bonds and Si-vinyl bonds. Then hydrosilation occurred between these two bands and finally silicone 3 was obtained, showing the potential of self-healing.

关键词： Ring-opening Hydrogenation Hydrosilylation Vinylmethydichlorosilane 1,3,5,7-Tetravinyl-1,3,5,7-tetramethyl-cyclotetrasiloxane

Enantioseparation of Racemic Naproxen Esters on Cellulose Tris (4-methylbenzoate) Chiral Stationary Phase

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Chinese Chemical Letters 2002年第2期13卷 151-152页

作者： Bao Hai SHAO Xiu Zhu XU Li ZOU xiao yun fu Department of Chemistry Zhejiang UniversityHangzhou 310027

Several kinds of racemic naproxen ester were successfully separated on CTMB chiral stationary phase with hexane-ethanol (98:2, vol./vol.) as the mobile phase. The influence of mobile phase composition and structure of racemic naproxen ester on chiral separation was studied and the chiral recognition mechanism of CTMB was discussed.

关键词： Cellulose tris (4-methylbenzoate) naproxen chiral stationary phase enantioseparation.

Influence of Mobile Phase Composition on the Enantioseparation of Methoxyl Flavanones with Self-prepared CDMPC Column and Chiral Recognition Mechanism

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Chinese Chemical Letters 2003年第4期14卷 401-403页

作者： Bao Hai SHAO Xiu Zhu XU Jian De LU Li ZOU xiao yun fu Department of Chemistry Zhejiang UniversityHangzhou 310027

The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.

关键词： Cellulose tris (3,5-dimethylphenylcarbamate) methoxyl flavanone chiral stationary phase enantioseparation.

Separation of Hydrophobic Neutral Compounds by Microemulsion Electrokinetic Chromatography

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

作者： xiao yun fu Xiu Zhu XU Jian De LU (Analytical and Testing Center, Zhejiang university, Hangzhou 310027) Zhejiang Univ Analyt & Testing Ctr Hangzhou 310027 Peoples R China

Microemulsion electrokinetic chromatography (MEEKC) was developed for the separation of hydrophobic neutral compounds. The effects of core phase and co-surfactant on the separations were investigated. Under the selected condition, good resolutions were obtained for the test mixtures. The separation efficiencies were higher than 105 theoretical plates per metre.

关键词： Microemulsion electrokinetic chromatography hydrophobic compounds

The Retention Behaviors of Benzene and Its Alkyl Homologues in Microemulsion Electrokinetic Chromatography

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Chinese Chemical Letters 2000年第6期11卷 549-550页

作者： xiao yun fu Wei YUAN Xiu Zhu XU Jian De LU(Analytical and Testing Center, Zhejiang University, Hangzhou 310027) Zhejiang Univ Analyt & Testing Ctr Hangzhou 310027 Peoples R China

The retention behaviors of benzene and its alkyl homologues in microemulsion electrokinetic chromatography were investigated in both anionic and cationic surfactant MEEKC systems. The effects of the composition of microemulsion on retention time and selectivity were studied. A good linear relationship was obtained between log k and the carbon number of alkyl chain.

关键词： microemulsion electrokinetic chromatography alkyl benzene

Determination of Constituents in Hair Dyes by Reversed-phase High-Performance Liquid Chromatography

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Chinese Chemical Letters 2000年第6期11卷 471-472页

作者： Bao Hai SHAO Jian Wei YAN Xiu Zhu XU xiao yun fu(Department of Chemistry, Zhejiang University, Hangzhou 310027) Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of 1,4-phenylenediamine, 4-aminophenol, 3-aminophenol, 1,3-benzendiol and 2,6-phenylenediamine in hair dyes was developed. The separation was carried out on a mu-Bondapak C-18 column with methanol-water containing 0.1% triethylamine and 0.02 mol/L NH4Ac (pH=5.20) (10:90. vol./vol.) as the mobile phase. Two real samples were analyzed.

关键词： hair dyes 1,4-phenylenediamine 4-aminophenol 3-aminophenol 1,3-benzendiol 2,6-phenylenediamine HPLC