The characteristic of electrochemical oxidation of aniline on SnO2/Ti electrode

The characteristic of electrochemical oxidation of aniline on SnO₂/Ti electrode is studied. The results indicate that SnO₂/Ti electrode dopedF plays a wonderful role in the oxidation of aniline comparing with Pt electrode. The kinetics factors that influence the oxidation rate of aniline on the SnO₂/Ti electrode are determined by the dissolving of the film on the electrode. The dissolving of the film consisted of intermediate products on the electrode is the slow step. The effects of aniline concentration, pH in aniline solution and the current density (i) on the rate of aniline oxidation, the complexity of intermediate products and the basic category of the intermediate products consisted of the film are introduced. Foundation item: Supported by the National Natural Science Foundation of PRC(10971023) Biography: Wany Yu-ling (1975-), female, Master, research direction: photochemical catalysis and electochemical catalysis.     

An effective novel reaction system for the photo-degradation of aqueous organic pollutants

A novel reaction system consisted of a supported TiO₂ film electrode, a Ru−Ti oxide film electrode and air (oxygen) electrode is reported. The air (oxygen) electrode can provide H₂O₂ continuously for homogeneous photochemical oxidation reaction on the spot. In this reactor, degradation reaction of aniline occur from interface of TiO₂ film to all solution which is irradiated by ultraviolet ray. The degradation rate of aniline was characterized by measuring the change of chemical oxygen demand (COD) in solution under different conditions. It was found that the degradation rate of aniline in the novel system increased apparently as compared with single heterogeneous photocatalysis and homogeneous photochemistry system. It can be explained in terms of combining acts of heterogeneous photocatalysis and homogeneous photochemistry. Foundation item: Supported by the National Natural Science Foundation of China (10791033) Biography: CAI Nai-cai (1946-), male, Associate professor, Research direction: electrochemical catalysis and photocatalysis.     

Oxidation and adsorption of Co at Pt−Au-SPE electrodes

Pt−Au-SPE electrodes made by the successive chemical deposition of Au and Pt on Nafion membranes were tested and compared with the single metal-SPE electrodes for surface oxidation, CO adsorption and oxidation. Part of the surface of the binary metal electrodes behaves differently from either Au or Pt single metal-SPE electrode for CO_ads oxidation, revealing surface modulation effects in the binary metal electrode. However, these mudulated surfaces have no appreciable contribution to the electrode activity for CO oxidation. The electrode activity for CO oxidation is mainly governed by the total Pt surface area of the binary electrodes. The predeposited Au was found to be favorable for higher dispersion of the successively deposited Pt. Foundation item: Supported by the National Natural Science Foundation of China Biography: YANG Jing (1972-), female, Lecturer, Wuhan University of Technology.     

Measurement of trace lead (II) in water samples with biomacromolecule heparin modified electrode

A new method for electrode modification and accumulation with a biomacromolecule and subsequent voltammetric quantittion of metal ions is described. Heparin is used as the surface modifier, and the method is based on formation of the heparin complex of lead (II). The voltammetric responses were evaluated with respect to electrolyte, pH, preconcentration time, and lead concentration. The electrode composition, voltammetric wave form and other variables have also been taken into account. A detection limit of 3.0×10⁻⁹ mol/L has been obtained by preconcentration for 20 min. The method is sensitive, simple and relatively rapid, with a relative standard deviation of 5.2% at the 1.0×10⁻⁷ mol/L level. Supported by the Trants-Century Training Program Foundation for the Talents from the State Commission of Education of China: the national Natural Science Foundation of China and the Opening Laboratory Foundation of Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. Li Huiling: Born in July 14, 1972. Master of Science.     

Voltammetric response and electrocatalysis of glassy carbon electrode modified with monolayer nickel hydroxide

The glassy carbon (GC) electrode modified with a monolayer nickel hydroxide (GC/Ni(OH)₂) was prepared by immersion of GC substrate in 1.0×10⁻³ mol/L NiSO₄ solution, and then cyclic voltammetric scanning in 0.20 mol/L KOH. Similarly, GC/Co (OH)₂ electrode was prepared too. The experiments showed that the voltammetric behavior of GC/Ni (OH)₂ electrode in 0.20 mol/L KOH is more stable than that of GC/Co(OH)₂. It was found that the GC/Ni(OH)₂ electrode acts as an effective electrocatalysis for the oxidation of hydrazine. Supported by the Trans-Century Training Program Foundation for the Talents from the State Commission of Education of China and the National Natural Science Foundation of China Liu Shouqing: born in Dec. 1962. Postgraduate     

Electrocatalytic oxidation of H<Subscript>2</Subscript>O<Subscript>2</Subscript> at a carbon paste electrode modified with a nickel (II)-5, 11, 17, 23-tetra-tert-butyl-25, 27-bis(Diethylcarbamoylmethoxy) calix[4] arene complex and its application

Electrochemical behavior of a carbon paste electrode (CPE) modified with nickel(II)-5, 11, 17, 23-tetra-tert-butyl-25, 27-bis(diethylcarbamoylmethoxy) calix[4]arene (Ni (II)-L) complex and its electrocatalytic activity towards the oxidation of hydrogen peroxide were investigated by cyclic voltammetric technique in a 5.0×10⁻² mol/L NaClO₄+1.0×10⁻³ mol/L NaOH solution. It was found that Ni(II)-L acts as an effective catalyst for the oxidation of hydrogen peroxide. The modified electrode exhibited a linear response over a hydrogen peroxide concentrations in the range of 2.0×10⁻⁵−1.0×10⁻⁴ mol/L with a detection limit as low as 1.0×10⁻⁶ mol/L. The relative standard deviation was 3.5% for 5 successive determinations of H₂O₂ at 1.0×10⁻⁵ mol/L. The modified electrode was used successfully in rainwater analysis. Foundation item: Supported by the Natural Science Foundation of Hubei Province (98J040). Biography: Li Chun ya(1972-), Ph. D. candidate, research direction: electroanalysis and electrosynthesis.     

Voltammetric Response of Epinephrine at Carbon Nanotube Modified Glassy Carbon Electrode and Activated Glassy Carbon Electrode

0Introduction Epinephrine(EP)isanimportantcate cholamineneurotransmitterinthemammaliancentralnervoussystem,whichissecretedbythesu prarenalglandalongwithnorepinephrine.Itisgen erallyusedtotreathypertension,bronchialasthma,organicheartdisease,andincardiacsurgeryand myocardialinfarction[1].VariousmethodshavebeendevelopedforEPstudy,suchascapillaryelectro phoresis(CE)[2],highperformanceliquidchroma tography(HPLC)andflowinjectionanalysis(FIA)[3].Numerousobservationsontheelectro chemicalbehavio…     

A study on ionospheric HF channel with bitemporal response and scattering function

At first the bitemporal response method is introduced to solve the scattering function of the ionospeeric channel. We can get the scattering function, as a function, of the group path time delay and Doppler frequency. Thus Doppler effect resulting from the continuous movement of the ionosphere is analyzed to study the characteristics of the various ionospheric irregularities and diturbance. many possible problems and correction are researched lastly. Foundation item: Supported by the National Natural Science Foundation of China (69571020) and the Research Fund for the Doctoral Program of Higher Education (RFDP1999048602) Biography: Chong Yan-wen(1972-), male, Ph. D. candidate, research direction: ionospheric modeling and inversion.     

Studies of several systems with air electrode electro-synthesizing H<Subscript>2</Subscript>O<Subscript>2</Subscript> on the spot for degrading aniline in aqueous

A gas diffusion electrode (air electrode) with a high current efficiency of electro-synthesizing H₂O₂ using O₂ in air was prepared. The several systems with air electrode as cathode of electro-synthesizing H₂O₂ on the reaction spot for degrading aniline in aqueous—electro-Fenton system, photo-excitation electro-H₂O₂ system and photo-electro-Fenton system, were developed. The rates of decomposition of H₂O₂ and mineralization of aniline were experimentally measured respectively under different conditions, and the results indicated there has an excellent parallel relation between decomposition rate of H₂O₂ and mineralization rate of aniline. Especially, photo-electro-Fenton system, where H₂O₂ is decomposed the fastest, is the best system of oxidizing and degrading organic toxicants. Compared photo-electro-Fenton system with photo-Fenton system, important role is revealed in the interface of air electrode. In this paper, the mineralization mechanism of aniline in the photo-electro-Fenton system was also discussed. Foundation item: Supported by the National Natural Science Foundation of China (200710026) and Foundation of Environmental Sciences Academy of Jiangsu Province. Biography: Cao xiao-yu (1979-), male, Master candidate, research direction: Electrochemistry     

安培法直接测定水体中COD的方法研究

以Ti/PbO2-Pt-Hg/Hg2Cl2为电极组成三电极体系,采用安培法直接测定水体中葡萄糖COD值。优化测试条件为:工作电极电位1.4 V,电解液浓度0.02 mol/L,电解时间1.5 min。工作电极的电流响应值与COD值在标准溶液20～200 mg/L范围内呈线性关系,检出限为10 mg/L。通过增大电位气泡更新法来再生工作电极具有简便、快速,重现性好的优点,当其与标准法对照用于实际水样COD的测定时相对误差<3%。     

数字PD-PID控制的打号机随动系统

介绍了碳素行业电极打号机电气传动装置随动系统的组成,分析了采用数字双模(PD-PID)控制器的工作原理并给出了程序框图.通过1 a多的运行实践证明,本系统具有稳态精度高、定位准确、无振荡、快速性好等静、动态优良控制性能.     

Voltammetric determination of estrogens based on the enhancement effect of surfactant at carbon paste electrode

Highly sensitive voltammetric method for the determination of estrogens, based on the enhancement effect of cetyltrimethylammonium bromide (CTAB) has been described. In the presence of CTAB, the oxidation peak currents of estrogens (estradiol, estrone, estriol, estradiol valerate and diethylstilbestrol) as the carbon paste electrode (CPE) increased significantly after open-circuit accumulation. The peak current was proportional to the concentration of estradiol over the range from 5×10⁻⁹ to 2.5×10⁻⁶ mol·L⁻¹. The detection limit was 8×10⁻¹⁰ mol·L⁻¹ at 6 min of accumulation. The total amounts of estrogens in the blood serums were determined and the average recovery was 104.92%. Under the conditions used, the electrode process of estradiol was examined the mechanism for peak current enhancement was also discussed. Foundation item: Supported by the National Natural Science Foundation of China (60171023) and the Natural Science Foundation of Hubei Province (99J060) Biography: Wu Kang-bing(1977-), male, Ph.D. candidate. research direction: bioelectrochemistry.     

纳米复合氧化物修饰碳糊电极在检测海洛因中的应用

应用自制的纳米复合氧化物对碳糊电极进行修饰,以该电极为工作电极,213型铂电极为对电极,饱和甘汞电极为参比电极,研究海洛因对Belousov-Zhabotinsky (B-Z)振荡反应的影响.结果表明:按质量比2:1制备的纳米复合氧化物/石墨粉纳米铁酸钴碳糊电极的振荡曲线规则、周期稳定、振幅较大、电极重现性好、使用时间...     

Ferrocene-Nafion修饰厚膜碳糊电极的葡萄糖传感器研究

以基于丝网印刷技术制作的厚膜碳糊电极为基底电机,用二茂铁为介体、Nafion修饰厚膜碳糊电极制备了葡萄糖传感器．Nafion涂于电极表面上形成的膜具有强的附着力,防止了二茂铁及酶的流失,电极稳定性提高．并且由于低的工作电位（＋025vsSCE）和Nafion膜的阳离子交换作用,基本上消除了电活性物质（抗坏血酸、尿酸）的干扰,具有防污能力．该酶传感器的检测上限可达18mmol／L,响应时间小于60s.     

The electro-optical effects of liquid crystallines side-chain polysiloxane

The electro-optical properties of liquid crystalline side chain polymers with siloxane groups as main chain are reported. It is shown that this type of LCPs (liquid crystalline polymers) with main chain (Si−O) has lower glass transition temperature and smaller elastic constant, which leads to shorter response time, especially. The LCPs with strong polar mesogenic groups (CN) have higher positive Δε value, which results in lower threshold voltage and shorter response time. Supported by National Natural Science Foundation of China Li Kaiyang: born in 1963. Lecturer     

One method for improving RAID5 performance

As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It is a general method to improve RAID5 performance by using cache. However, it often happens that the data is not hit in cache, in this case, the RAID5 performance also will be very poor. The method based on combination of disk I/O operations has been proposed for impriving the I/O response time through reducing the number of low-level operations. According to theoretic analysis and experimental test, we find that RAID5 access time and data transfer rate could be largely improved than conventional method. Foundation item: Supported by the National Natural Science Foundation of China under grant 69773046 and (69973017), and Defense Advanced Research Foundation of China under grant (98J15. 1. 1. JW0516) Biography, Chen Qiong (1963-), female, Ph. D candidate, research interests: computer architecture, parallel processing, disk arrays.     

重金属离子对葡萄糖氧化酶电极抑制作用的研究

采用二氧化硅溶胶-凝胶固定化酶技术制备了葡萄糖氧化酶电极,优化了酶电极的工作条件。考察了酶电极的响应性能以及Hg^2＋,Fe^3＋等重金属离子对酶电极响应的抑制影响。实验结果表明在E=0．8V,pH=5．0,θ=25℃时,Hg^2＋,Fe^3＋的存在抑制了酶电极对葡萄糖的电流响应,且抑制电流的大小和重金属离子浓度在一定范围呈线性关系,线性范围分别是0～1．5μmot／L和0～60μmol／L。将被抑制的酶电极浸入EDTA溶液中10min后,酶电极可以恢复部分响应性能。     

基于普鲁士蓝修饰碳糊电极的电化学传感器对偏二甲肼检测研究

在偏二甲肼的氧化中使用普鲁士蓝作为合适的电子转移调节剂,应用普鲁士蓝修饰碳糊电极(PB/CPE)作为工作电极,循环伏安法技术可以应用在偏二甲肼的电催化氧化上。通过观察PB/CPE的电化学行为和偏二甲肼在工作电极上的电化学响应,来具体评估PB/CPE对偏二甲肼溶液浓度测定的可靠性。结果表明,普鲁士蓝可以作为促进偏二甲肼氧化的催化剂,利用电流测定法得出测定的线性范围为0.3~80 mg·L~(-1),检测限为4.6×10~(-5)g·L~(-1)。该传感器表现出许多优势,其中包括很少的干扰、简单的准备和良好的稳定性。     

电流变减振器阻尼力计算及影响因素分析

电流变减振器的工作模式主要有流动模式、剪切模式和复合模式等三种。针对流动模式的充气式电流变减振器，推导出其在压缩和复原过程中阻尼力的计算公式。压缩和复原阻尼力主要由三部分构成，即电流变液基础粘度引起的本底阻尼力，电场强度函数的电致阻尼力和气室气体引起的压力。电流变减振器的特点就在于可以通过调节电场强度来控制电致阻尼力，达到调节复原和压缩阻尼力的目的。并对影响阻尼力大小的结构因素进行了讨论分析。     

An Efficient Grid Service Discovery Mechanism Based on the Locality Principle

With the explosion of services in grid environment, it＇s necessary to develop a mechanism which has the ability of discovering suitable grid services efficiently. This paper attempts to establish a layered resource management model based on the locality principle which classifies services into different domains and virtual organizations （VOs） according to their shared purposes. We propose an ontologybased search method applying the ontology theory for characterizing semantic information. In addition, we extend the UD- D1 in querying, storing, and so on. Simulation experiments have shown that our mechanism achieves higher performance in precision, recall and query response time.