铜在储氢合金表面包铜电极中的行为

在密封的电池体系中，包铜储氢合金电极具有较好的抗氧化能国和；而在强碱性溶淤 中，铜在电极工作的电位范围内具有一定的稳定性，但当扩展扫描范围，将出现铜的氧化不这原反应。     

玻碳电极上铜电沉积初期行为研究

运用循环伏安和计时安培法研究酸性镀铜溶液中硫酸和 2_巯基苯骈咪唑对铜电沉积初期行为的影响 .实验表明铜的电沉积经历了晶核形成过程 ,其电结晶按瞬时成核三维生长方式进行 ,硫酸对铜的电沉积具有加速作用 ,而 2_巯基苯骈咪唑对铜的电沉积起阻化作用 ,两者均不改变铜的电结晶机理     

循环伏安量热法研究铜在铂电极上的电沉积

循环伏安量热法研究了欠电位沉积条件下，铜在ＬｉＣｌＯ４溶液中，铂电极上的电沉积过程，循环伏安热谱图和循环伏安微分热谱图表明，铜离子的电沉积为－放热过程，其中铜－铂（层）相互作用能为－３２２７．０ｋＪ／ｍｏｌ．沉积铅的电氧化包括了吸热的活性和放热的氧化两个过程，活化过程的焓变为７４７．０ｋＪ／ｍｏｌ，氧化过程的焓变为－１８９．９ｋＪ／ｍｏｌ，与热力学数据一致。     

非晶态Fe-P合金电极的电沉积制备及其储锂性能

应用电沉积技术制备了Fe-P合金电极材料。采用X射线衍射(XRD)和扫描电子显微镜(SEM)分析了该合金材料的相结构和表面形貌。XRD分析结果表明电沉积的Fe-P合金具有非晶态结构。电化学性能测试表明：平面结构的Fe-P合金电极首次放电(脱锂)容量达542 mAh·g^-1,首次循环的库仑效率为60%;50周循环之后放电容量为366 mAh·g^-1。用非原位的XRD和SEM对电极的充放电机理进行了初步研究,结果表明,首次充电(嵌锂)过程中形成Li₃P相,电极表面生成纳米棒结构铁-磷合金,它能有效缓解锂嵌入/脱出时引起的合金结构变化,抑制合金材料的体积膨胀,从而提高该合金电极的充放电效率和循环性能。     

p—Si上电沉积Ni—W合金薄膜

利用恒电流沉积法，在ｐ－Ｓｉ上制备出不同Ｗ含量和不同结构的Ｎｉ－Ｗ薄膜，研究了镀液温度，ｐＨ值，电流密度对镀层组成的影响，结果表明，提高温度有利于获得高Ｗ含量的合金。     

电沉积Ni－La合金上的阴极析氢行为

在电解水制氢工业中,为降低能耗人们在研制电催化活性高的析氢电极材料方面做了大量工作,主要有纯金属电极、合金电极及复合电极等.Arul Raj等用电沉积方法获得了Ni-Co,Ni-Zn,Ni-W及Ni-Cr等镍基合金电极,发现这些电极的析氢催化活性有很大差别.本文从电解质水溶液中制备了Ni-La合金电极,是一种理想的析氢电极材料.     

p—Si上电沉积Ni—W—P薄膜的结构与热稳定性

研究了ｐ－Ｓｉ上恒电流沉积Ｎｉ－Ｗ－Ｐ合金薄膜组成与结构的关系，讨论了镀层的组成、结构随沉积时间的变化．测定了非晶合金的晶体结构随热处理温度的改变以及ＤＴＡ曲线，结果表明，非晶Ｎｉ－Ｗ－Ｐ合金在晶化过程中形成两个纳米超微晶相，非晶Ｎｉ－Ｗ－Ｐ薄膜的热稳定性远高于通常使用的非晶Ｎｉ－Ｐ薄膜．     

激光增强电沉积铜过程的研究

用旋转圆盘电极法研究了激光照射下铜的电沉积过程。证明激光照射引起电极界面微区温度升高, 使平衡电位正移, 交换电流i~o和电荷传递系数α均增大, 剧烈的微区搅拌提高了极限扩散电流。这些变化都加快了电沉积速度, 使高速局部电镀有可能实现。     

乳状液法制备ZnS纳米粒子

乳状液法制备ＺｎＳ纳米粒子黄宵滨马季铭＊程虎民赵振国齐利民（北京大学化学系北京１００８７１）关键词硫化锌，纳米粒子，乳状液，混合乳化剂１９９６－０５－２０收稿，１９９６－０９－０４修回国家自然科学基金资助项目近年来，利用反胶束或Ｗ／Ｏ微乳制备超细粒子...     

紫外线辐照制备单分散ZnS纳米颗粒

以硫代硫酸钠和乙酸锌为反应物、柠檬酸为调控剂,在紫外光辐照下制备出单分散的ZnS纳米颗粒。采用XRD、TEM、低温氮吸附-脱附、HRTEM和EDS等方法研究了反应物浓度、辐照时间和柠檬酸用量等因素对产物颗粒尺寸和分布的影响。结果表明,随着反应时间延长,产物收率增高,平均晶粒度增大,比表面积变小。反应物浓度对产物组成和比表面积有较大影响,但对产物的平均晶粒度影响不大。适量添加柠檬酸,有利于制备单分散的ZnS纳米颗粒。     

Formation of Nonspherical Particles with Uneven Surface in Emulsion Copolymerization of Styrene and Methacrylic Acid with Nonionic Emulsifier

Summary: Emulsion copolymerization of styrene and methacrylic acid with nonionic emulsifier and potassium persulfate as initiator gave nonspherical copolymer particles having uneven surface. The formation was based on the coagulation of byproduct nano-sized (ca. 35 nm) particles, which were formed throughout the copolymerization until monomer phase disappeared, onto main submicron-sized (234 ∼ 445 nm) particles.     

硅氧烷乳液聚合过程中大颗粒形成机理研究Ⅰ．阳离子型乳液的耐电解质稳定性

探讨了二甲基聚硅氧烷阳离子型乳液耐电解质稳定性的影响因素。结果表明,加入少量的非离子型表面活性剂与阳离子型乳化剂并用进行乳液聚合,可以保护乳液粒子,防止由于电解质引起的乳液粒子的相互凝聚而形成大颗粒。     

纳米尺寸ZnS化学增感剂

本文发现硫化锌纳米粒子对卤化银乳剂的化学增感作用 .采用水不溶性的硫化锌纳米粒子作为化学增感剂 ,与水溶性的硫代硫酸钠增感剂相比 ,可以在不增加乳剂灰雾的条件下明显提高卤化银乳剂的感光度及反差     

硅氧烷乳液聚合过程中大颗粒形成机理研究：Ⅰ.阳离子型乳液的耐电解质…

探讨了二甲基聚硅氧烷阳离子型乳液耐电解质稳定性的影响因素。结果表明，加入少量的非离子型表面活性剂与阳离子型乳化剂并用进行乳液聚合，可以保护乳液粒子，防止由于电解质引的乳液粒子的相互凝聚而形成大颗粒。     

On the emulsion polymerization of styrene in the presence of a nonionic emulsifier

The batch emulsion polymerization kinetics of styrene (St) initiated by a water-soluble peroxodisulfate in the presence of a nonionic emulsifier was investigated. The polymerization rate versus the conversion curves showed two nonstationary rate intervals, two rate maxima, and Smith–Ewart Interval 2 (nondistinct). The rate of polymerization and number of nucleated polymer particles were proportional to the 1.4th and 2.4th powers, respectively, of the emulsifier concentration. Deviation from the micellar nucleation model was attributed to the low water solubility of the emulsifier, the low level of the micellar emulsifier, and the mixed modes of particle nucleation. In emulsion polymerizations with a low emulsifier concentration, the number of radicals per particle and particle size increased with increasing conversion, and the increase was more pronounced at a low conversion. By contrast, in emulsion polymerizations with a high emulsifier concentration, the number of radicals per particle decreased with increasing conversion. This is discussed in terms of the mixed models of particle nucleation, the gel effect, and the pseudobulk kinetics. The formation of monodisperse latex particles was attributed to coagulative nucleation and droplet nucleation for the polymerizations with low and high emulsifier concentrations, respectively. The effects of the continuous release of the emulsifier from nonmicellar aggregates and monomer droplets, the close-packing structure of the droplet surface, and the hydrophobic nature of the emulsifier on the emulsion polymerization of St are discussed. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4422–4431, 1999     

Dendronized Cellulose Nanocrystals as Templates for Preparation of ZnS and CdS Quantum Dots

Cellulose nanocrystals (CNC) isolated from bleached bagasse pulp were modified with a second-generation isocyanate dendron (G2-dendron) to prepare dendronized cellulose nanocrystals (DCN). Transmission electron microscopy (TEM), elemental analysis for nitrogen, Fourier transform infrared (FTIR) and ¹³C magic angle spinning nuclear magnetic resonance (¹³C MAS NMR) proved occurrence of the modification of cellulose nanocrystals surfaces. The dendronized cellulose nanocrystals were used as templates for formation of ZnS and CdS quantum dots with uniform diameter at low temperature in water. The prepared DCN/QDs were highly soluble in water. TEM images showed that the size of the prepared quantum dots was about 5 nm in diameter. UV-Visible and fluorescence spectroscopy showed absorption and emission at wavelength values lower than that reported for bulk ZnS and CdS.     

Synthesis of size-tunable zinc blende ZnS nanocrystals

Quasi-polyhedral ZnS nanocrystals with monodisperse tunable sizes of 40, 52, 62, 73, 82, 94, 103, and 110 nm have been synthesized in aqueous solution by regulating the amounts of thioacetamide, zinc acetate, and acetic acid added. The mixture was heated to 120°C in an oven for 10–20 min to produce the nanocrystals. Structural characterization reveals the formation of cubic zinc blende ZnS with some polycrystallinity, which possibly influences their optical properties, that is, the measured band gaps do not give a continuous narrowing trend with increasing particle size. However, when particle sizes are expressed in terms of volumes, the absorption band positions show steady red shifts with increasing crystal dimensions and very small wavelength changes for nanocrystals beyond 90 nm. Thus, these ZnS nanocrystals still possess some size-dependent optical properties despite their polycrystalline nature.     

Preparation of Nanosized Metallic Particles in Polyaniline

The preparation of nanosized gold and palladium particles in polyaniline has been carried out via the reduction of AuCl(3) or Pd(NO(3))(2) by polyaniline in either aqueous media or N-methylpyrrolidinone (NMP). When the reduction of AuCl(3) was carried out in NMP solutions of polyaniline, the Au particles were on the order of 20 nm. The reduction of AuCl(3) or Pd(NO(3))(2) by polyaniline in the powder form in aqueous media resulted in the accumulation of the elemental Au or Pd on the surface of the polyaniline particles. Subsequent dissolution of the polyaniline in NMP resulted in metal particles of about 50 to 200 nm being dispersed in the NMP solution of polyaniline. The rate of metal salt reduction and the size of the metal particles were found to be strongly dependent on the medium used, the initial ratio of metal ions to polyaniline, and the reaction time. The polyaniline-metal particle systems were characterized using X-ray photoelectron spectroscopy, UV-visible absorption spectroscopy, and FTIR spectroscopy. Scanning and transmission electron microscopy and laser light scattering were used to determine the size of the metal particles in polyaniline. Copyright 2001 Academic Press.