双环己酮草酰二腙-CTMAB光度法测定铝合金中的铜

研究了双环已酮草酸二腙（BCO）与铜（Ⅱ）的显色反应,建立了直接测定铝合金中微量铜的光度分析方法。在氨性缓冲溶液介质中,在表面活性剂CTMAB作用下,铜（Ⅱ）与BCO形成蓝色的配合物,配合物在606nm处有最大吸收,铜（Ⅱ）的含量在0～80μg／25mL范围内服从比耳定律,表观摩尔吸光系数为1．79×104L·mol^-1·cm^-1。该方法简便快速,应用于铝合金中铜的测定,测定结果与标准值相符,得到了满意的结果。     

壳聚糖-离子液体自组装膜的制备及其性能

采用N一丁基吡啶六氟磷酸盐EBuPy]PF6和壳聚糖（Chi）作为修饰剂,通过静电吸附作用在玻碳电极表面形成稳定性较强的自组装膜修饰电极[BuPy]PF4-Chi／GC．采用电化学阻抗谱技术和循环伏安法研究自组装膜在K3[Fe（CN）4]-K4EFe（CN）6]溶液中的电化学行为,结果表明：形成的自组装膜对溶液与基底间的界面电子转移有强烈的阻碍作用,氧化还原峰电流与扫速的1／2次方在20～100mV／s的范围内呈良好的线性关系,表明该电极过程受扩散控制．该修饰电极对铜离子有很好的选择性,响应灵敏度相比于未修饰的电极提高60倍,铜离子的溶出线性伏安峰电流与其浓度在1．56×10“～6．25×10-4mol·L-1范围内呈良好的线性关系（R=0．9966）．     

亚甲基兰中性红聚合膜电极对多巴胺的分析测定

在中性溶液中用重复电位扫描法在玻碳电极上制备了亚甲基兰混合中性红聚合膜。其聚合是在高电位引发下,氧化中性红和亚甲基兰产生自由基发生链式引发聚合时该聚合物修饰电极在pH值为8．4时对多巴胺有良好的催化氧化能力,在3×10^-6～3×10^-4mol／L范围与峰电流成线性关系。可用于多巴胺的测定。     

Li1-xNaxV3O8电极在硫酸锂-水-乙醇体系中的电化学性能

A series of Li_(1-x)Na_xV_3O_8 materials was prepared by solution reaction followed by calcination method and their electrochemical performances in 2 M Li_2SO_4-water-ethanol solution as negative electrodes for aqueous electrolyte lithium ion battery were studied and compared each other.X-ray diffraction analysis revealed that partially substituting sodium for lithium in LiV_3O_8 could increase the interlayer distances of (100) plane.Cyclic voltammetric experiments have demonstrated that the Li~ insertion and extraction kinetics of Li_(0.7)Na_(0.3)V_3O_8 is superior to that of LiV_3O_8.Charge/discharge results showed that the discharge specific capacity of Li_(0.7)Na_(0.3)V_3O_8 electrode is higher than that of LiV_3O_8 electrode.     

抗坏血酸存在下六氮杂铜配合物修饰金电极对多巴胺的分析测定

利用自组装的方法制备了一种新型六氮杂铜配合物修饰的金电极。采用循环伏安法和电化学隧道扫描显微镜对该电极进行了表征。计算了该电极电子转移系数为0.42,标准速率常数为38S^-1。该电极可以有效地催化氧化多巴胺,当抗坏血酸浓度为1-5mmol/L时,可用于多巴胺的分析测定,检测限低至1.8×10^-8mol/L。     

水/有机两相体系中苯甲醛与苯乙酮缩合反应的研究

合成了3种季铵盐型阳离子表面活性荆(C16H33)2N(CH3)2Br(双十六烷基二甲基溴化铵),C16H33,NC33H45(CH3)2Br(二十二烷基十六烷基二甲基溴化铵),C16H33NC12H25(CH3)2Br(十六烷基十二烷基二甲基溴化铵),并考察了其对水/有机两相体系中苯甲醛与苯乙酮Aldol缩合反应性能的影响.结果显示,含有两条疏水长链的阳离子表面活性剂对水/有机两相体系中苯甲醛与苯乙酮Aldol缩合反应具有明显的加速作用,其催化活性明显高于其它类型的表面活性剂;结果还显示,阳离子表面活性剂分子中疏水碳链的数目增加、疏水碳链的增长均有利于Aldol缩合反应.     

Electrochemical behavior of insulin on pretreated carbon black electrode enhanced with silicon carbide nanostructure

We previously reported the direct electrochemical detection of insulin at bare carbon electrodes. Here a novel modified acetylene carbon black paste electrode(SiC/CB-CPE), based on the outstanding characteristics of silicon carbide nanostructure,was developed for the electrooxidation of insulin in alkaline solution and it was characterized by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) in 5 mmol/L Fe(CN)63-/4- solution. It is found that silicon carbide nanostructure doped into the CB-CPE greatly facilitates the redox electrochemistry of Fe(CN)63-/4- probe and the electrochemical oxidation of insulin. The electrooxidation of insulin is a one-electron and one-proton reaction and an irreversible adsorption-controlled electrode process. The anodic oxidation current increases linearly with the concentration of insulin from 1×10-7mol/L to1.2×10-6mol/L in 0.1 mol/L Na2CO3-NaHCO3 buffer solution(pH 10.0) and the detection limit was 50 nmol/L. In addition, the SiC/CB-CPE shows good sensitivity, reproducibility, renewability and capacity of resisting disturbance.     

机械化学法合成羟基磷灰石

以CaCO3 和CaHPO4 ·2H2 O为原料 ,研究羟基磷灰石合成过程中混合料在水介质及高速球磨条件下发生的机械化学作用 .混合料球磨 1h可合成结晶良好、含碳酸根及磷酸氢根的羟基磷灰石 ,其化学组成与由骨水泥水化而成的羟基磷灰石相同 ,颗粒呈球状或短棒状 ,粒径分布范围为 2 0— 10 0 nm .     

亚甲基兰聚合膜的电化学表征及性质

在碱性溶液中用重复电位扫描法在玻碳电极上制备了亚甲基兰聚合膜.亚甲基兰的聚合是在高电位引发下,氧化亚甲基兰产生自由基发生链式引发聚合.用铁氰化钾作为探针采用循环伏安法和电化学扫描电镜表征了不同聚合圈数的电极的表面性质.随着扫描圈数的增加,聚合膜的厚度也增加,同时电极由导体向绝缘体转变.电极表面的形貌图也说明了这一现象.     

中性红聚合膜的电化学表征及性质

在中性溶液中用重复电位扫描法在玻碳电极上制备了中性红聚合膜.中性红的聚合是在高电位引发下,氧化中性红产生自由基发生链式引发聚合.用铁氰化钾作为探针采用循环伏安法和电化学扫描电镜表征了不同聚合圈数的电极的表面性质.随着扫描圈数的增加,聚合膜的厚度也增加,同时电极由导体向绝缘体转变.电极表面的形貌图也说明了这一现象.     

表面活性剂增敏催化光度法测定痕量亚硝酸根

基于在稀硫酸介质中溴代十六烷基吡啶 (CPB)对亚硝酸根 (NO-2 )催化溴酸钾氧化碘曙红褪色反应的增敏作用 ,建立了测定NO-2 的表面活性剂增敏催化动力学光度法 .由于加入增敏剂 ,灵敏度显著提同 .lgA0 /A值与NO-2 含量在 0～ 1.0 μg/mL范围内存在线性关系 ,检出限量为0 .0 6 μg/ml.方法用于水样、蔬菜中痕量亚硝酸根的测定 ,结果较好     

Effects of Surfactant on Solubility and Microbial Conversion of Steroid

Enhancing the dispersion and dissolution of substrate particles in substrate water suspension is a feasible way to improve steroid bioconversion. The aim of the present study is to investigate the effects of applying surfactant to microbial conversion system on the dispersion, solubilization and in turn bioconversion of steroid substrate. The model system is hydroxylation of substrate 19α- 17α-epoxy- 4-pregnene- 3.2It-dine by microbial enzymes from Rhizopus nigricanl. The results show that the presence of substrate leads to an increase in critical micelle concentration （ CMC） of surfactant PSE compared with the normal CMC of PSE in aqueous solution. The grinding time during substrate suspension preparation affects the substrate aqueous solubility differently with the varied surfactant concentrations while barely making any difference in substrate solubility in the absence of surfactant. The properly prolonged grinding time can make up for the loss in substrate solubility arising from the reduction in surfactant concentration. The surfactant complexes composed of surfactants PSE and MGE at appropriate ratios are screened out with orthodoxy experiment method. the interaction between PSE and MGE exerts the most prominent effects on substrate bioconversion, and the surfactant complexes show more beneficial effects on steroid bioconversion than the surfactant PSE used alone.     

基于褐藻酸钠改性纳米金静电排斥作用的新型电化学免疫传感器的研制

通过胱胺将负电性的褐藻酸钠(AS)共价结合到纳米金表面形成聚合体，并以此来标记三碘甲状腺氨酸(T3)．T3抗体固定在金电极上构成检测T3的电化学免疫传感器．通过免疫反应，标记T3和待检测的T3结合到金电极表面，使电极表面微环境发生显著改变，用Fe(CN)6^4 为电化学探针，用循环伏安法获取电极表面微环境改变的电化学信息来检测T3、其检测的线性范围为100—10000pg／mL，检测限为45pg/mL.     

碳纳米管负载单（双）核四硝基铁酞菁的制备和催化性能

制备出了碳纳米管负载单（双）核硝基铁酞菁,采用电化学手段研究了碳纳米管与金属酞菁的最佳配比,最佳热处理温度以及它们催化氧还原反应的动力学特征。结果表明：对于单核硝基铁酞菁而言,其与碳纳米管的最佳比例为2：3,而双核硝基铁酞菁与碳纳米管的最佳比例为1：4：样品的最佳热处理温度为500℃,催化剂催化氧还原反应的电极过程均受表面吸附所控制。     

非晶态MgsoNi50氢化物电极的充放电滞后特性

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钼酸银修饰电极的制备及其电化学性能研究

采用电化学方法首次在导电基体玻碳电极上制备出了钼酸银薄膜饰电极，研究了修饰电极的电化学行为．发现该电极在硫酸溶液中进行伏安扫描时具有良好的稳定性．研究了修饰电极对抗坏血酸的电催化作用。     

Oxidation Characteristics of the Reactivity Between Pyrite and Aqueous Arsenate

Natural pyrites contain high levels of adsorbed and structurally incorporated arsenic(As),which may simultaneously result in the release of As and affect the oxidation process of pyrite.However,the oxidation and electrochemical behaviors of As on the oxidation reactivity of pyrites are still not clear.In this study,pyrite was prepared by a hydrothermal method and applied to study the oxidation mechanism between pyrite and aqueous arsenate.Analyses of X-ray diffraction,X-ray photoelectron spectroscopy,and scanning electron microscopy demonstrate that the as-prepared sample is an octahedron-like pyrite with high purity and crystallinity.The interaction between As(V)and pyrite as well as the electrochemical behaviors of pyrite oxidation in the presence of aqueous arsenate were investigated under acidic conditions by an ion analysis method,cyclic voltammetry(CV),Tafel,and electrochemical impedance spectroscopy(EIS).The results of the chemical reaction indicate that electrons are transferred from S _2~(2-)to dissolved oxygen with the formation of SO _4~(2-)in the initial As(V)concentration range of 0–0.3 mmol/L.In the initial As(V)concentration range of 0.4–1.2 mmol/L,electrons are transferred from S _2~(2-)to As(V)with the formation of elemental S ~(0 )and As(III).The CV,the Tafel plot and EIS analyses indicate that aqueous arsenate in an electrolyte promotes oxidation reactivity and passivation of the pyrite electrode.Moreover,the electron transfer rate increases with increasing aqueous arsenate concentration in the electrolyte.     

测定痕量铊的纳米氧化铝吸附分离-镉试剂2B分光光度法

研究了在pH11．5～12．5的NH3-NH4Cl介质和TritonX-100存在下,镉试剂2B与铊（Ⅲ）的显色反应。铊（Ⅲ）与镉试剂2B形成红色配合物,在测定波长500nm处,表观摩尔吸光系数为7．29X10·L·mol-1·cm-1,线性方程为A=0．0139C＋0．0032,相关系数是0．9993,线性范围是肛800μg／L。建立了采用纳米氧化铝吸附铊（Ⅲ）,与其他干扰元素分离,在水相体系快速、准确测定多金属结核GBW07296和环境水样中痕量铊的方法,回收率为96-102％,相对标准偏差不大于2．4％。     

Preparation and electrochemical application of praseodymium modified TiO<Subscript>2</Subscript>-NTs/SnO<Subscript>2</Subscript>-Sb anode by cyclic voltammetry method

A Pr-doped TiO₂-NTs/SnO₂-Sb electrode was prepared by a simple method, cyclic voltammetry(CV). The methyl orange(MO)aqueous solution was selected as a simulated wastewater. The ordered microstructural TiO₂-NTs substrate was synthesized by an electrochemical method to obtain large specific surface area and high space utilization. The phase structure, electrode surface morphology and electrochemical properties of electrodes were characterized by XRD, SEM and electrochemical technology, respectively. The results showed that praseodymium oxide was successfully doped into the SnO₂-Sb film by CV method. Due to the doped Pr, the oxygen evolution potential increased from 2.25 V to 2.40 V. The degradation of MO was investigated by UV-vis. The C _t /C ₀ (φ) was studied as a function to obtain the optimal parameters, such as the amount of doped Pr, current density and initial dye concentration. In addition, the degradation process followed pseudo-first-order reaction kinetics and the rate constant was 0.099 3 min^-1. The result indicated that the introduction of Pr reduced the formation of oxygen vacancies or enhanced the formation of adsorbed hydroxyl radical groups on the surface, thus leading to better activity and stability.     

催化动力学光度法测量环境样品中的痕量铜

研究了在磷酸介质中,铜(Ⅱ)催化过氧化氢氧化偶氮砷(Ⅲ)褪色反应的适宜条件与影响因素,建立了动力学光度法测量痕量铜的新方法.该方法的线性范围为0-6μg/25mL,间接摩尔吸光系数为ε=1.75×105L.mol-1·cm-1.标准加入回收率为92.5%.用于水样品和发样品分析,取得满意效果.