聚N—异丙基丙烯酰胺溶液的温度依赖关系

用自由基聚合法合成了聚Ｎ－异丙基丙烯酰胺（ＰＮＩＰＡＡＭ）样品，用乌氏粘度计考查了该聚合物的四氢呋喃（ＴＨＦ）溶液和水溶液的粘度与温度的依赖关系。发现ＰＮＩＰＡＡＭ－ＴＨＦ体系的特性粘数随温度升高而增大，ＰＮＩＰＡＡＭ－Ｈ２Ｏ体系的特性粘数－温度曲线表现出较为复杂的变化规律。并用实验确定的特性粘数对合成样品的分子量进行了表征Ｍｎ＝８．４４×１０＾５ｇ·ｍｏｌ＾－１。     

特丁醇和水混合溶剂多组分电解质热力学HC1—NaCl—tert._C4H9OH—H2…

本在恒定特丁醇质量分数ｘ＝０．１０的条件下，应用电动势测定了无液接界电池（Ａ）和电池（Ｂ）的电动势：Ｐｔ，Ｈ２（１．０１３×１０＾５Ｐａ）｜ＨＣ（ｍ），ｔｅｒｔ．－Ｃ４Ｈ９ＯＨ（ｘ），Ｈ２Ｏ（１－ｘ）｜ＡｇＣｌ－Ａｇ （Ａ） Ｐｔ，Ｈ２（１．０１３×１０＾５Ｐａ）｜ＨＣｌ（ｍＡ），ＮａＣｌ（ｍＢ），ｔｅｒｔ．－Ｃ４ＨｏＯＨ，Ｈ２Ｏ（１－ｘ）｜ＡｇＣｌ－Ａｇ （Ｂ）根据电池（Ａ）电动势确定了     

聚N-异丙基丙烯酰胺溶液的粘度的温度依赖关系

用自由基聚合法合成了聚Ｎ 异丙基丙烯酰胺（ＰＮＩＰＡＡＭ）样品，用乌氏粘度计考查了该聚合物的四氢呋喃（ＴＨＦ）溶液和水溶液的粘度与温度的依赖关系．发现ＰＮＩＰＡＡＭ ＴＨＦ体系的特性粘数随温度升高而增大，ＰＮＩＰＡＡＭ Ｈ２Ｏ体系的特性粘数 温度曲线表现出较为复杂的变化规律．并用实验确定的特性粘数对合成样品的分子量进行了表征Ｍｎ＝８４４×１０５ｇ·ｍｏｌ－１．     

影响水滑石晶体结构的因素

制备了Ｍｇ１－ｘＡｌｘ（ＯＨ）２（Ａ＾ｎ－）ｘ／ｎ．ｍＨ２Ｏ型水滑石，讨论了配料组成，滴料方式，陈化过程等制备条件对水滑石晶体组成和晶体结构的影响。在配料Ｍｇ／Ａｌ比相同的条件下，得到的Ｍｇ１－ｘＡｌｘ９ＯＨ）２（ＣＯ３）０．５ｘ．ｍＨ２Ｏ晶体中Ｍｇ／Ａｌ比并不一定相同。     

功能聚间苯二胺膜用于免疫传感器分析

以电化学聚合法在石墨电极上获得聚间苯二胺膜（ＰＭＰＤ），并建立了快速、灵敏的膜质量检验方法：辣根过氧化物酶（ＨＲＰ）标记ＰＭＰＤ膜－邻苯二胺（ＯＰＤ）反应法，对聚合、活化等条件作了研究；进一步制成了检测乙肝表面抗原（ＨＢｓＡｇ）和检测鼠免疫蛋白（ＭＩｇＧ）的免疫电极，对血清样品作了检测．结果表明：２．５Ｖ电池电压下，于含０．１２ｍｏｌ／ＬＭＰＤ的１．２ｍｏｌ／ＬＨ２ＳＯ４中聚合２０ｍｉｎ，再以３０ｇ／Ｌ浓度的戊二醛活化４ｈ，所得ＨＲＰ标记电极及免疫电极重现性好；检测ＨＢ－ｓＡｇ和ＭＩｇＧ的线性范围分别为０．１～３．２ｍｇ／Ｌ及０．１～１０ｍｇ／Ｌ     

“推拉”型希夫碱染料的光化学和光电化学性质

合成了一种光降解的两亲性希夫碱染料,（Ｅ）－Ｎ－十八烷基－２－「２－（４－Ｎ,Ｎ－二甲基氨基苯基）胺烯基」吡啶碘化物（ＰＮ２）,考察了它的成膜性能,并成功地应用ＬＢ膜技术将其转移到石英基片或ＩＴＯ电极上形成单层膜,对其光化学和光电化学性质的研究表明：它是一个具有二阶非线性光学性质（ＳＨＧ）和光电响应性质（ＰＥＣ）的可降解有机染料,化合物ＰＮ２单层ＬＢ膜的宏观二阶非线性系数Ｘｚｚｚ＾（２）为１４５．     

用银和铅标记人白蛋白的离子选择电极电位法研究

用离子选择电极电位法研究了银和铅与人白蛋白（ＨＳＡ）的配合平衡。明确证实银和铅都与ＨＳＡ形成了单核配合物ＭＡ和ＭＡ２．Ａｇ－ＨＳＡ配合物的稳定性积β１１＝４．４×１０＾７，β１２＝１．０×１０＾１２；Ｐｂ＝ＨＳＡ配合物的β１１＝３．１×１０＾５，β１２＝２．０×１０＾９。根据ＨＳ与人白蛋白羊抗血清（ＧＡＨＡ）的免疫反应，用银和铅分别标记ＨＳＡ时，测定ＧＡＨＡ（效价１：４０）的线性范围是０．２～２．     

杂多阴离子的有机金属化学(Ⅲ)──缺位Keggin阴离子PW_9O_(34)~(9-)的酯基锡杂多配合物的合成及性质

利用酯基锡与缺位Ｋｅｇｇｉｎ结构杂多阴离子ＰＷ９Ｏ９－３４反应，合成了６种新的杂多阴离子有机金属配合物Ｍ９［（Ｒ′ＯＯＣＣＨＲ″ＣＨ２ＳｎＯＨ２）３（ＰＷ９Ｏ３４）２］·ｘＨ２Ｏ（Ｍ＝（ＣＨ３）４Ｎ＋，Ｋ＋；Ｒ′＝ＣＨ３＿，ＣＨ３ＣＨ２＿；Ｒ″＝Ｈ，ＣＨ３＿），通过元素分析、ＩＲ光谱、紫外电子光谱、１ＨＮＭＲ、３１ＰＮＭＰ、１８３ＷＮＭＲ和ＴＧＡ－ＤＳＣ热分析等测试手段对标题配合物进行了表征和性质研究，确定该系列配合物为Ａ－β－ＰＷ９型夹心配合物结构．     

应用CS2在Ag—S键中的插入反应生成新型Ag原子簇化合物研…

应用ＣＳ２在Ａｇ－Ｓ键中的单核插入物（ＰＰｈ３）２Ａｇ（Ｓ２ＣＳＰｒ３＾ｉＣ６Ｈ２）与ＣＨ２Ｃｌ２－Ｐｒ＾ｉＯＨ混合溶剂反应，生成了一个中性的三核银簇合物，并用Ｘ射线单晶衍射法测定了其晶体结构。     

甲醇燃料车尾气净化催化剂的研究Ⅱ.甲醇深度氧化用银催化剂上吸附物种的原位红外研究

利用原位红外技术研究了ＣＨ３ＯＨ，ＣＯ，Ｏ２等在５％Ａｇ／γＡｌ２Ｏ３上的吸附情况及ＣＨ３ＯＨ和Ｏ２共吸附时表面物种的变化．结果表明，在表面纯净的Ａｇ／γＡｌ２Ｏ３催化剂上，甲醇的解离吸附仅发生在γＡｌ２Ｏ３上；表面预吸附氧后，可大大增强Ａｇ对ＣＨ３ＯＨ的解离吸附，当吸附的［ＣＨ３Ｏ］与［Ｏ］在Ａｇ／γＡｌ２Ｏ３上相互作用时，出现吸附态甲醛、甲二氧基、甲酸根等中间物种．Ｏ２在Ａｇ／γＡｌ２Ｏ３上存在非解离吸附（Ｏ－２），在真空中较易脱附，但在氧气氛下可于１００℃时稳定存在．     

Electro-Catalytic Oxidation of Ascorbic Acid at a Cobalt-Salen Polymer Modified Electrode and Analytical Applications

ABSTRACT

The preparation and electrochemical characteristics of electrodes modified by cobalt complexes of N, N' - bis(salicylidene)-ethane -1, 2- diamine (salen) are described. A cobalt-salen polymer film modified electrode has strong electro-catalytic effects for the oxidation of ascorbic acid. The anodic peak potential of ascorbic acid shifted negatively for 400 m V. The catalytic reaction rate constant determined by rotating disk experiments is 7.08×10⁵ mol s^?1 cm^3. The catalytic mechanism and the effect of film thickness are discussed. A sensitive voltammetric response for ascorbic acid was obtained covering a linear range from 1.0×10^?6 to 1.0×10^?3 mol-L^?1 The modified electrode showed good stability and reproducibility. The electrode was used to the determination of ascorbic acid in fruit juices and showed promising results compared with conventional methods. The electro-catalytic effect of several metal-salen complexes and a similar Schiff base derivative for ascorbic acid was compared.     

Electrocatalytic oxidation and flow-injection determination of ascorbic acid at a graphite electrode modified with a polyaniline film containing electrodeposited palladium

A method for forming a composite film on the surface of a graphite electrode is proposed. Conditions for detecting the maximum catalytic current under batch and flow conditions are determined. A procedure for the electrocatalytic determination of ascorbic acid at the graphite electrode modified with a polyaniline film containing palladium particles is proposed. The catalytic effect of this electrode manifests itself by a ～300-mV decrease in the peak potential of ascorbic acid oxidation and by a multiple increase in the peak current of ascorbic acid oxidation as compared to the unmodified electrode. The linear dependence of the electrocatalytic response of the composite electrode on the concentration of ascorbic acid is observed down to 1 × 10^?8 M and 2.5 nmol of ascorbic acid under batch and flow-injection analysis conditions, respectively.     

苯胺在邻-氨基苯磺酸功能化的玻碳电极上聚合及其对抗坏血酸的电催化氧化

通过电氧化法将ABS分子以CN键共价键合在玻碳电极(GCE)表面,形成ABS分子单层膜修饰的GCE(ABS/GCE),在此电极上对AN进行电聚合,从而制备了聚苯胺/邻氨基苯磺酸复合膜修饰电极(PAN-ABS/GCE/CME).由于ABS中磺酸基功能团对PAN的掺杂作用使PAN在中性或碱性介质中都能呈现出较好的电化学活性.研究表明,PAN-ABS/GCE/CME在PBS(pH 6.8)中对AA的电氧化具有催化作用,其氧化峰电位为0.17 V,比在裸GCE上(0.39 V)负移了0.22 V,峰电流明显升高.AA在修饰电极上的氧化峰电流与其浓度在0.5～16.5 mmol/L范围内呈良好的线性关系,其线性回归方程为ipa(μA)=20.2+6.20CAA,r=0.9973; 检出限(3δ)为7.2 μmol/L,电极具有较好的稳定性和重现性.并采用计时电流法对AA催化氧化的扩散系数和催化速率常数进行了研究.     

聚苯胺薄膜修饰电极对抗坏血酸的电催化氧化

本文表明聚苯胺(PAn)薄膜修饰电极对水溶液中的抗坏血酸(AH_2)在较宽的pH范围和较宽的浓度范围内均有良好的电催化氧化作用, 为EC平行催化过程。利用旋转圆盘电极(RDE)进行了催化过程动力学分析, 求出了催化反应动力学参数。在抗坏血酸浓度10~(-2)～10~(-6) mol·L~(-1)范围内, 催化峰电流与AH_2浓度均成良好的线性关系, 且PAn薄膜修饰电极具有很好的稳定性, 有应用分析抗坏血酸的意义。     

铜氮杂配合物修饰金电极对抗坏血酸的分析测定

本实验制备了一种新型的氮杂铜配合物修饰金电极,该电极可用于抗坏血酸的测定。采用循环伏安法和扫描电化学显微镜技术对电极进行了表征。该修饰电极可催化氧化抗坏血酸,相对于裸电极抗坏血酸在修饰电极上氧化电位移动了250mV,并且氧化电流在抗坏血酸的浓度为5.0×10−7 to 4.0×10−5 mol/L时呈线性关系,检测限为4.8×10-8 mol/L。用此方法测定抗坏血酸与文献报道的测定结果一致,这表明该电极可用作抗坏血酸测定的电化学传感器。     

聚血红素修饰电极对儿茶酚类化合物和抗坏血酸氧化的电催化作用研究

电催化是化学修饰电极研究的中心课题之一,血红素是一种重要的铁卟啉化合物,其中的铁原子能够以两种价态存在．我们采用循环伏安法将血红素修饰于电极表面,得到了氧化还原体（ｒｅｄｏｘ）型化学修饰电极,并用于儿茶酚类化合物和抗坏血酸的电催化氧化研究．采用伏安法...     

Amperometric sensor for the determination of ascorbic acid based on Cobalt hexacyanoferrate modified electrode fabricated through a new route

A new approach was attempted to prepare a chemically modified electrode using Cobalt hexacyanoferrate (CoHCF) as the redox mediator and to study its stability and electrocatalytic activity for ascorbic acid (AA) oxidation. The basic principle underlying the electrode modification is the coordination of cobalt ion with the amino nitrogen of aniline adsorbed on the surface of a graphite rod. This surface was subsequently derivatized with ferrocyanide to get CoHCF film on the electrode surface. The CoHCF modified electrode as prepared above was characterized using cyclic voltammetry. The effect of scan rate, supporting electrolyte and pH of the medium on the performance of the modified electrode was investigated. The CoHCF modified electrode exhibited good electrocatalytic activity towards the oxidation of ascorbic acid and gave a linear response from 5.52 x 10(-5) M to 3.23 x 10(-2) M with a correlation coefficient of 0.9929. The detection limit was found to be 3.33 x 10(-5) M. Hydrodynamic voltammetry and chronoamperometry studies for the oxidation of ascorbic acid were also carried out. The electrode was highly stable and exhibited good reproducibility. This modified electrode was also applied for the determination of ascorbic acid in commercial samples.     

抗坏血酸在PPy-HEImTfa/Pt电极上的电催化氧化及其机理

以铂为基底电极,在1-乙基咪唑三氟乙酸盐(HEImTfa)离子液体中电化学合成导电聚吡咯(PPy),制得PPy-HEImTfa/Pt电极;采用循环伏安法研究了PPy-HEImTfa/Pt电极对抗坏血酸的电催化氧化性能.结果表明:PPy-HEImTfa/Pt电极对0.1mo·lL-1抗坏血酸具有较高的电催化氧化活性,与相同条件下硫酸溶液中在铂表面修饰的聚吡咯(PPy-H2SO4/Pt)电极和裸铂电极相比,其氧化峰电位分别降低了0.10和0.19V,氧化峰电流分别增加了3.0和3.6mA.同时采用原位傅里叶变换红外(insitu FTIR)光谱技术对抗坏血酸在PPy-HEImTfa/Pt电极上的电氧化机理进行了研究,结果表明:抗坏血酸在PPy-HEImTfa/Pt电极上首先被氧化为脱氢抗坏血酸,在水溶液中脱氢抗坏血酸迅速发生水合作用形成水合脱氢抗坏血酸,它进一步水解并发生内酯开环反应生成2,3-二酮古洛糖酸;在较高电位下,部分抗坏血酸最终被氧化成CO2.     

聚溴酚蓝修饰玻碳电极的制备及电化学性质

在含溴酚蓝的磷酸缓冲溶液中,应用循环伏安法于经预处理的玻碳电极上形成聚合物薄膜.结果表明,在-1. 0V~+1. 8V(vs.Ag/AgCl)扫描电位之间形成的薄膜具有较高的电活性和稳定性.该电极对抗坏血酸电化学氧化有催化作用,既使抗坏血酸的氧化电位负移了 270mV,又增大了其氧化峰电流.催化峰电流与抗坏血酸浓度在 2. 5~250μg/mL范围内呈良好的线性关系.     

Electrocatalytic oxidation of ascorbic acid and voltammetric determination with a ferrocene-modified platinum electrode

Ferrocene attached to the surface of a platinum electrode catalyses the electrochemical oxidation of ascorbic acid in acidic buffer solutions. The overpotential for ascorbic acid oxidation is decreased by 150 mV at pH 2.2 compared with reaction at bare platinum; and an increase in anodic current and decrease in cathodic current for the redox reaction of ferrocene occurs on addition of ascorbic acid to the solution. The ferrocene-modified electrode is useful for the voltammetric determination of ascorbic acid in natural fruit juices. The advantages result from the electrocatalytic effect and from the prevention of adsorption of inhibitory substances from solution.