聚天青A膜修饰电极的电化学特性及其对亚硝酸根的电催化性能

在玻碳电极上以循环伏安法制备了聚天青A膜修饰电极(PAAE) ,天青A能够在玻碳电极上形成稳定的聚合膜 ;通过正交试验确定了电聚合天青A的最佳条件 ,研究了该修饰电极的电化学特性 ,并讨论了其对亚硝酸根的电催化还原作用 ;结果表明 ,亚硝酸根在PAAE上有很好的电流响应 ,催化峰电流与亚硝酸根浓度在1.0×10-5 ～4.0×10-3 mol/L之间呈良好的线性关系     

水相湿法改性纳米碳酸钙表面性质的研究

用特定的表面改性剂在水相中对纳米碳酸钙的悬浮液进行了湿法改性。红外光谱和热失重分析证明,改性剂与碳酸钙之间以化学键结合;沉降体积和接触角的测定结果说明改性粒子在液体石蜡中的润湿性和疏水性得到了提高;透射电子显微镜照片显示改性粒子在液体石蜡中有更好的分散性;体系粘度实验表明改性粒子与液体石蜡之间有较好的相容性。     

Donor-acceptor properties, catalytic activity, and negative charge exoemission from the alumina surface modified with lithium cations

Donor-acceptor properties of alumina modified with lithium cations were studied by ESR of paramagnetic complexes of adsorbed anthraquinone. The results were compared with the data on negative ion emission (exoemission) accompanying the decomposition of isopropyl alcohol in the adsorption layer. The data on the activity measured by the pulse microcatalytic technique in isopropyl alcohol decomposition are discussed. Small additives of lithium were found to promote catalytic activity of the samples. The role of acid and basic sites in isopropyl alcohol decomposition was discussed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 616–621, April, 2006.     

表面包覆改性对纳米CeO2分散性的影响

了改善纳米CeO2在Zn-Al类共晶合金中的分散性,采用超声液相包覆法对纳米CeO2进行表面活性剂表面包覆改性,并用AES测定了包覆层的厚度,用TEM研究了CeO2的团聚状况,用TGA分析了有机物包覆层的炭化温度范围,最后用FE-SEM观察了CeO2在复合材料中的分散情况。结果表明,包覆在纳米CeO2表面的厚度约为20 nm的表面活性剂层提高了微粒的分散性,而且该包覆层在495℃时已经炭化。热力学计算的结果也表明,炭化层能与氧化膜反应,该反应提高了CeO2与基体间的润湿性,并使其均匀分布在基体合金中。     

粘土矿物的结构特征及其应用研究

阐述了贮量巨大、用途广泛的粘土矿物，其充分开发应用的关键，在于根据其结构特征，并通过适当的物理、化学方法加以改造、以适应各种不同工业应用的要求。并以我们对粘土矿物进行活化、改性、层间插入及其工业应用产品开发的初步研究成果，阐明利用粘土硅酸盐多层次结构的可变性，开拓新的应用性能的可能性及粘土矿物充分开发应用的途径。     

铜离子交换改性的沸石催化剂上甲烷的非氧芳构化

已有研究表明，ＭｏＯ３／ＨＺＳＭ５是甲烷非氧芳构化的优良催化剂，在９７３Ｋ下甲烷转化率达６％～８％，苯选择性高于８０％，这为非氧气氛下甲烷的芳构化反应展示了非常诱人的前景［１～１２］．但是，该催化剂的活性和稳定性尚有待进一步提高，目前已有使用Ｐｔ，...     

Surface modification of imide containing polymers I: Catalytic groups

This paper describes basic studies of the surface modification of polyimide covered wires for insulation of electrical machines. Drain-off of the impregnating resin during production should be reduced by introduction of surface catalytic groups. ¹H NMR kinetic analysis of aminolytic ring opening reaction of low molecular model compounds for polyimides showed very fast modification reactions. The catalytic effect of various functional groups on unsaturated polyester imide, acrylate and epoxy resins was investigated by DSC. Co(II)-catalysts and tertiary aliphatic amines proved highest activity for double bond containing systems and epoxy resins, respectively. Aminolytic treatment of Kapton^® slides was followed by ATR-IR spectroscopy. Plate-plate rheometer measurements of epoxy resins employing tertiary amine-treated Kapton^® slides proved significantly reduced gelling temperature.     

Complete Oxidation of Methane over Palladium Supported on Alumina Modified with Calcium,Lanthanum,and Cerium Ions

The activity and thermal stability of Pd/Al_2O_3 and Pd/(Al_2O_3 MO_x)(M=Ca,La,Ce) palladium catalysts in the reaction of complete oxidation of methane are presented in this study.The catalyst supports were prepared by sol-gel method and they were dried either conventionally or with supercritical carbon dioxide.Then they were impregnated with palladium nitrate solution.The catalysts with unmodified alumina had a high surface area.The activity and thermal stability of the alumina- supported catalyst was also very high.The introduction of calcium,lanthanum,or cerium oxide into alumina support caused a decrease of the surface area in the way dependent on the support precursor drying method.These modifiers decreased the activity of palladium catalysts,and they required higher temperatures for the complete oxidation of methane than unmodified Pd/Al_2O_3.The improvement of the palladium activity by lanthanum and cerium support modifier was observed only at low temperatures of the reaction.     

Fabrication of Poly(allylamine)ferrocene Monolayer Based on Electrostatic Interaction and Its Electrocatalytic Oxidation of Ascorbic Acid

A poly(allylamine)ferrocene monolayer was built on the surface of gold electrode modified with negatively charged alkanethiol based on electrostatic interaction. The electrochemical behavior of the modified electrode was characterized by cyclic voltammetry in detail. The modified electrode was shown to exhibit excellent electrocatalytic response to the oxidation of ascorbic acid. The anodic overpotential was reduced by about 170 mV compared with that obtained at a bare gold electrode. The modified electrode possesses several attractive features, such as simple preparation, fast response and good chemical and mechanical stability.     

Preparation of complex carbon-silica adsorbents with different properties

Summary The surface properties of complex adsorbents prepared through the pyrolysis of benzyl and n-heptyl alcohols and their mixtures on the surface of silica gel were investigated. The reactions were carried out in an autoclave at 500°C. A series of adsorbents having different porous structure, chemical nature of the adsorption centers and their topography were obtained. The best resolution of different mixtures was obtained by the carbon-silica adsorbent prepared through the pyrolysis of n-heptanol.