高铁酸盐在SnO2-Sb2O3/Ti电极上的选择性电化学合成

合成了SnO2-Sb2O3/Ti电极材料.实验结果证实,在14mol/LNaOH水溶液中和完全避免析氧反应的条件下,Fe(Ⅱ)物种在该电极上进行电化学氧化并生成FeO42-.结果表明,Fe(OH)3在浓NaOH溶液中发生酸式电离,形成可溶于水的FeO2-,该离子的浓度随着碱溶液浓度变化而发生明显变化,而且它还是发生化学氧化和电化学氧化的反应物.在SnO2-Sb2O3/Ti电极上,FeO42-的电化学还原起始电位为0.38V(vs.Hg/HgO,14mol/LNaOH),FeO2-电化学氧化起始电位为0.54V.结果还表明,用电化学方法氧化Fe(Ⅱ)物种生成FeO42-是个多步骤过程.     

用双氧水绿色氧化环己酮合成己二酸的研究

以30%的双氧水为氧化剂, 钨酸钠与含N或O的双齿有机配体(草酸)形成的络合物为催化剂, 在无有机溶剂、无相转移剂的条件下, 研究了环己酮氧化制己二酸的反应. 研究结果表明, 用廉价的草酸为配体, 最佳反应条件为钨酸钠∶草酸∶环己酮∶30%的双氧水的物质的量比为2.0∶3.3∶100∶350, 在92 ℃下反应12 h, 可制得80.6%的己二酸; 用GC-MS跟踪了氧化过程中三种主要物质环己酮、己内酯及己二酸含量随反应时间的变化关系, 提出了其主要氧化机理为环己酮首先经Beayer-Villiger氧化反应生成己内酯, 己内酯进一步氧化成己二酸.     

Socket with built-in valves for the interconnection of microfluidic chips to macro constituents

This paper reports a prototype for a standard connector between a microfluidic chip and the macro world. This prototype demonstrate a fully functioning socket for a microchip to access the outside world by means of fluids, data signals and energy supply. It supports up to 10 channels for the input and output of liquids or gases, as well as compressed air or vacuum lines for pneumatic power lines. The socket has built-in valves for each flow channel. It also contains 28 pins for the connection of electrical signals and power. Built-in valves make it possible to control the flow in each channel independently. A chip ( 11.0 x 11.0 x 0.9 mm) can be mounted into or dismounted from the socket with one touch. The fluidic connectors of the socket are designed to contact vertically on the top of chip. And the electrical connectors (the spring array) of that physically support the chip and contact lead pads at the bottom of chip. No adhesives or solders are used at any contact points. The pressure limit for the connection of working fluids was 0.2 MPa and the current limit for the electrical connections was 1 A. This socket supports both serial and parallel processing applications. It exhibits great potential for developing microfluidic systems efficiently.     

N－（N＇，N＇－二甲氨基甲基）丙烯酰胺－过硫酸钾引发丙烯酰胺聚合的研究

Ｎ－（Ｎ＇，Ｎ＇－二甲氨基甲基）丙烯酰胺－过硫酸钾引发丙烯酰胺聚合的研究潘松汉，唐康泰，王贞，王真智中国科学院广州化学研究所，广州，５１０６５０关键词Ｎ－（Ｎ＇，Ｎ＇－二甲氨基甲基）丙烯酰胺、反应动力学、氧化还原体系、相对分子质量及分布为了制备高质量...     

MoCo/Y, MoNi/Y氮化物催化剂的结构和CH4+CO2重整反应性能

采用氨气还原法制备了NaY分子筛负载的MoCo/Y、MoNi／Y双组氮化物催化剂，用XRD和EXAFS方法征了样品的结构，并测定了其在CH4＋CO2重整反应中的活性，在氧化态时，MoCo/Y样品中主要存在CoMoO4和Co3O4两种物相，Mo的配位状态接近于CoMoO4，而Co的配位状态更接近于Co3O4，MoNi／Y样品中主要有NiMoO4和NiO两种物相，Mo的配位状态接近于MiMoO4，而Ni的配位状态可能是NiMoO4和NiO两种化合物中Ni配位状态的平均效果，Ni-Mo之间的朴素作用似乎比Co-Mo相对较强，在氮化态时，两种样品中Mo的配位状态较为相似，但即不同于MoO3，也不同于单组分γ－Mo2N.Co和Ni的配位状态都不同于各在氧化态下的状态，且都在相同的位置出现一个新强峰，这似乎表明MoCo和MoNi生成了结构相似的氮化物，在CH4＋CO2重整反应中，氮化态MoCO/Y和MoNi/Y的活性大大超过非负载单组分γ－Mo2N催化剂，其中MoNi/Y的活性相对更好一些，且活性随Ni含量增加而提高。     

含Cu复合氧化物对NO和CO吸附和活化的TPSR研究

利用MS－TPD法并结合XRD、化学分析等对催化剂进行了表征，探讨了K2NiF4结构La2-x(Sr，Th)xCuO4±λ系催化剂中三个典型样品LaSrCuO4、La2CuO4和La1.7Th0．3CuO4对NO、CO及CO＋NO等小分子的吸附性能和活化规律。结果表明：NO吸附量的大小与催化剂中氧空位含量有关，吸附强度和脱附峰种类与金属离子氧化态有关。CO在氧缺陷复合氧化物催化剂上的吸附是首先变为碳酸根，并在高温以CO2物种脱出．在NO和CO的共吸附过程中，有关NO的吸、脱性能与单独NO－TPD中NO的吸脱附规律相似，表明NO在NO＋CO共吸附的竞争吸附过程中，优先吸附起决定作用，而受CO的影响较小．NO的吸附是NO活化分解的必要条件．     

老年人彩度对比敏感度函数研究及滤波应用

为研究老年人彩色视觉频率响应特性，获取彩度对比敏感度与空间频率之间的函数关系，本文在LCH均匀颜色空间基础上，固定明度和色调角值，以彩度作为变量，设计人眼彩度对比敏感度实验，进行人眼视觉观察实验。获得彩度对比敏感度与空间频率的关系，并构建指数型对比敏感度函数模型。经分析表明老年人眼彩度对比敏感度随着空间频率的增加，产生先升高再缓慢降低的变化，各色调角下彩度对比度存在差异。经分析人眼对比敏感度差异与人眼视觉辨色特性有很大的相关性。并且，将构建的对比敏感度函数模型用于实现基于人眼视觉系统的滤波处理。     

Synthesis and properties of niobia films derived from niobium pentaethoxide

The hydrolysis of niobium pentaethoxide precursor in the presence of triethylamine (TEA) is discussed. Three precursors with TEA/Nb(OEt)₅ mole ratios of 0.25, 0.4 and 0.8 were prepared. Niobia colloids with different appearance were obtained after autoclaving the above precursors at 250°C during 12 h. The surface roughness and microstructure of niobia films prepared with the colloids by spread coating method are strongly dependent on the TEA/Nb(OEt)₅ mole ratio. At a value of 0.4 TEA/Nb(OEt)₅ mole ratio, a niobia film with large surface roughness can be achieved. It is opaque and mechanically stable and has differently ordered needle microstructure. The crystalline structure and photoelectrochemical property of niobia film with the largest surface roughness were examined. The effect of CO₂ gas bubbling, reflux and addition of 2-methoxyethanol on the hydrolysis of Nb(OEt)₅ and the nature of the Nb₂O₅ films is also discussed.     

Formation,growth mechanism and packing sequences of binary alloy cluster anions from laser ablation of mixtures of lead and transition metals

By using laser ablation of the mixtures of a transition metal (M: Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Pd, Ag) plus lead, M/Pb binary cluster anions were observed except for Zn, and the number of transition metal atoms contained in the binary clusters is at most 4. This behavior is different from that reported previously for M/Ge binary clusters. The experiments indicate that it is also very difficult to form Al/Pb clusters. The distribution patterns of M/Pb binary alloy cluster anions are remarkably similar to those of pure Pb clusters, consistent with a formation mechanism in which transition metal atoms are sequentially attached to [M(x-1)Pb(y)](-) clusters and thus form [M(x)Pb(y)](-) clusters by a simple condensation process. As the number of transition metal atoms increases, the intensities of binary clusters gradually decrease. It is proposed that [MPb(4)](-) and [MPb(5)](-) cluster anions might be the unit building blocks of M/Pb binary cluster anions, and the layer packing sequences for magic clusters are predicted on this basis. The [M(x)Pb(y)](-) binary clusters containing 13 atoms (x + y = 13; x not equal 0) are proposed to have an icosahedral structure.     

A Facile Synthesis of Indole-based Conjugated Derivatives

A novel synthetic method was developed for the preparation of indole-based conjugated derivatives with satisfied yields. By applying this strategy, a series of new compounds were prepared conveniently. All the obtained new indole derivatives were characterized by spectroscopic analyses, giving satisfactory data corresponding to their expected molecular structures.