厚度效应对La0.67Ca0.33MnO3单晶薄膜电输运特性的影响

研究了外延La0.67Ca0.33MnO3（LcMO）／SrTiO3（100）和LCMO／NdGaO3（110）（NGO）薄膜的电输运特性随薄膜厚度的变化。尽管LCMO／STO和LCMO／NGO表现出不同的晶格畸变，但是，研究发现，在结构与输运特性之间没有直接的依赖关系，表现晶格应变效应对薄膜的电输运特性没有影响，如电阻率、金属-半导体转变、极化子激发能。     

铈对铁基合金热腐蚀性能的影响

采用电化学极化电阻技术研究了铈对３１６不锈钢和表面涂覆ＣｅＯ２预氧化处理对ＨＫ４０合金耐热腐蚀性能的影响。结果表明，在合金中添加少量铈可以改善３１６不锈钢的耐蚀性能，特别是抑制沿晶界的内硫化；表面涂覆ＣｅＯ２可以明显ＨＫ４０合金的耐蚀性能，促进Ｃｒ２Ｏ３氧化膜的形成。     

失配因子σ2对掺杂锰基钙钛矿氧化物输运性质的影响

掺杂量、A位阳离子平均半径及失配因子是影响掺杂锰基钙钛矿氧化物从顺磁绝缘体到铁磁金属转变的主要因素，为了突出研究失配因子的影响，本文固定掺杂量和A位阳离子平均半径制备了一系列样品。0和5T磁场下电阻率与温度关系测量表明，随着失配因子的增加，绝缘体-金属转变温度向低温区移动且与σ^2岩保持线性关系；通过调节失配因子，样品La0.53Sm0.17Sr0.3MnO3的磁电阻在室温附近达到了极大值。结合样品的电输运行为，对实验结果进行了讨论。     

半导体氧化锡粉末直流电阻的测定

粒径为０．０２～１０μｍ的半导体氧化锡粉末在真空中充分脱气和施加高于４０ＭＰａ压力可获得重现性较好的直流电阻。无锑掺杂氧化锡粉末的直流电阻随试样冷却吸附的温度而异，讨论了多晶氧化锡粉末的结构对电阻测定的影响。     

PEG／PED-g-CB化学敏电阻材料的制备及其气敏性能的研究

以不同分子量聚乙二醇(PEG)为基体，PEG接枝改性的炉法炭黑(PEG-g-CB)为导电裁流子，采用溶液分散工艺制得一种新鞭的气敏传感器材料。研究了PEG分子量对接枝率及对各种溶剂蒸气的响应性、响应灵敏度的影响；用透射电子显微镜(TEM)和紫外—可见分光光度计考察了两种炭黑粒子分散行为、袁面特性差异及其对响应重复性、稳定性的影响。结果表明，PEG／PEG-g-CB复合材料化学敏电阻体对其良溶剂蒸气如THF、氯仿、丙酮具有很强的响应性，其电阻值可提高到初始电阻的10^4～10^6倍。将这种材料再放入干燥空气中时，电阻又恢复到初始值；而对其不良溶剂如正己烷、甲苯几乎不响应。随PEG分子量的提高，响应灵敏度下降；响应的重复稳定性受炭黑粒子分散行为的影响，从聚合物溶胀行为及逾渗导电理论解释了实验结果。     

硅太阳电池N型银浆用银粉的研究

通过在几种不同的银粉中加入含磷掺杂剂配制成N型银浆, 考察了不同银粉对其电池片的转换效率和接触电阻的影响.实验表明, 银粉的粒度和立体形状对转换效率的影响很大.     

La0.7Ca0.3MnO3薄膜庞磁电阻(CMR)现象的分析

针对La0.7Ca0．3MnO3薄膜材料中磁团簇的特性及其对材料庞磁电阻(CMR)现象的影响进行了研究。根据实验数据，利用Wagner等提出的数学模型，对La0.7Ca0.3MnO3薄膜中的磁团簇随温度的变化行为特性进行了研究；通过对La0.7Ca0．3MnO3薄膜相关实验数据的拟合，发现La0．7Ca0．3MnO3薄膜的居里温度范围应当在245～250K之间，从而进一步缩小了该材料居里温度的误差范围；还通过计算MR随磁团簇总角量子数J的变化，研究了制约和影响MR值的主要因素，发现磁团簇尺寸在La0．7Ca0.3MnO3薄膜的CMR现象中扮演了重要角色。     

二极管特性简化模型在染料敏化太阳能电池电流-电压曲线拟合及在光电特性参数评估中的应用

利用瞬态光电导技术研究了在一个大的偏压范围内染料敏化太阳能电池(DSSC)中的电荷收集和电荷复合过程的动力学. 结果表明, 在不同的电压下电荷收集速率远快于电荷复合速率, 用以解释电荷的收集效率几乎不变. 基于这个结果, 简化了DSSC二极管特性模型, 从而实现了对电流-电压(I-V)曲线的直接拟合. 利用这一模型拟合的结果提取出一系列与工作条件下DSSC光电转化过程相关的参数, 可以用以描述包括电荷生成、电荷收集和复合以及DSSC器件的整流特性等关键性质. 将这一拟合方法应用于不同叔丁基吡啶(TBP)浓度电解液的电池, 获得的结果表明, 不同TBP浓度可以导致电荷复合速率有较大的差别, 但对电荷的收集速率影响甚小, 这与I-V曲线拟合的结果非常吻合. 同时研究证明TBP浓度对电池的理想因子(m)的影响较为明显,即高浓度TBP的DSSC对应大的m值以及较慢的电荷复合速率.     

用电阻法研究铈对AlMgSi合金时效的影响

将含与不含Ｃｅ的ＡｌＭｇＳｉ合金丝状试样固溶淬火后于１８、３０、４０、５０、７０、１００、１２０及１４０℃等温度时效，原位测量试样时效过程的电阻变化。结果表明，在６ｈ时效时间内，除１４０℃之外，其余情形电阻均随时间单调上升，上升速率先大后小。在相同条件下，含Ｃｅ试样电阻相对升值ΔＲ／Ｒ０一般较不含Ｃｅ的小些，这是因为Ｃｅ使Ｇｐ区弥散度下降，尺寸粗化。     

电解液组成对尖晶石LiMn_2O_4中锂离子嵌脱过程的影响

运用电化学阻抗谱(EIS)研究了尖晶石LiMn2O4正极在1mol·L-1LiPF6-EC(碳酸乙烯酯)∶DEC(碳酸二乙酯)∶DMC(碳酸二甲酯),1mol·L-1LiPF6-EC∶DEC∶EMC(碳酸甲乙酯)和1mol·L-1LiPF6-EC∶DMC三种不同电解液中,-20-20℃范围内的阻抗谱特征随温度的变化.研究结果表明,温度强烈影响尖晶石LiMn2O4正极的阻抗谱特征,而电解液组成对尖晶石LiMn2O4正极阻抗谱特征的影响较小,但电解液组成对锂离子在尖晶石LiMn2O4正极中嵌入脱出过程相关动力学参数影响较大.测得尖晶石LiMn2O4正极在上述三种电解液中,锂离子迁移通过固体电解质相界面(SEI)膜的离子跳跃能垒平均值分别为7.60、16.40和18.40kJ·mol-1;电子电导率的热激活化能平均值分别为44.77、35.47和68.06kJ·mol-1;嵌入反应活化能平均值分别为52.19、46.19和69.86kJ·mol-1.     

Cationic polymerization of styrene with electrochemically generated perchloric acid—I

The electroinitiated polymerization of styrene in LiClO₄-propylene carbonate solutions leads to polystyrene at the anode through the formation of HClO₄. The influences on this polymerization of factors such as temperature, current, monomer and electrolyte concentrations, and dielectric constant of the medium, have been examined. The trends of the yields as functions of these factors show some anomalies. In particular, there is a maximum in the yield vs current curve. The molecular weights are relatively low, due to transfer processes, both spontaneous and involving monomer. The propagation proceeds by a cationic mechanism, in which free ions are in equilibrium with ion pairs.     

The Factors Influencing Nonlinear Characteristics of the Short‐Circuit Current in Dye‐Sensitized Solar Cells Investigated by a Numerical Model

A numerical model for interpretation of the light‐intensity‐dependent nonlinear characteristics of the short‐circuit current in dye‐sensitized solar cells is suggested. The model is based on the continuity equation and includes the influences of the nongeminate recombination between electrons and electron acceptors in the electrolyte and the geminate recombination between electrons and oxidized dye molecules. The influences of the order and rate constant of the nongeminate recombination reaction, the light‐absorption coefficient of the dye, the film thickness, the rate constant of geminate recombination, and the regeneration rate constant on the nonlinear characteristics of the short‐circuit current are simulated and analyzed. It is proposed that superlinear and sublinear characteristics of the short‐circuit current should be attributed to low electron‐collection efficiency and low dye‐regeneration efficiency, respectively. These results allow a deep understanding of the origin of the nonlinear characteristics of the short‐circuit current in solar cells.     

共晶基离子液体的钴电化学沉积

通过恒电流和恒电位方法,研究了不同温度下脲-氯化胆硷（氯仿）基或乙二醇-氯化胆硷（氯仿）基离子液体中氯化钴溶液在铜和钢阴极上的钴电化学沉积行为. 采用扫描电子显微镜和X射线衍射技术,考察了不同试验条件对钴电沉积行为及钴沉积层形貌的影响. 结果表明,当沉积电位达到-0.8 V和沉积电流密度达到-6.0 A·m^-2时,温度范围从30 °C到90 °C,添加0.05 mol·L^-1的五氧化二磷,可以从脲基和乙二醇基离子液体中沉积得到光滑、发亮和良好结合力的金属光泽钴层. 电化学沉积钴的阴极电流效率达到98%.     

基于氯化胆碱离子液体的铜电沉积研究（英文）

采用恒电流和恒电位方法,基于含有氯化铜溶液的乙二醇-氯化胆碱或硫脲-氯化胆碱离子液体,室温下在钢阴极上进行了铜的电沉积. 利用扫描电子显微镜和X-射线衍射技术研究了各种实验条件对电沉积的影响以及沉积层的形貌. 结果表明,室温下施加不超过-0.45 V的沉积电位和不超过-4.0 A·m^-2的沉积电流密度,可以同时从氯化胆碱基乙二醇和硫脲离子液体中沉积得到非常光滑、有光泽、致密且具有良好结合力、色泽鲜艳的铜金属涂层. 铜的电沉积阴极电流效率约为97%.     

Solvent and pH effects on fast and ultrasensitive 1,1'-oxalyldi(4-methyl)imidazole chemiluminescence

Solvent and pH effects on fast and ultrasensitive 1,1'-oxalyldi(4-methyl)imidazole chemiluminescence (OD4MI-CL) were studied. The influences of these two factors on the complex OD4MI-CL reaction are discussed within a conceptual prototype for developing aqueous and non-aqueous capillary electrophoresis (ACE and NACE) devices with OD4MI-CL detection. The reaction channel length and OD4MI yield from the reaction between bis(2,4,6-trichlorophenyl) oxalate (TCPO) and 4-methylimidazole in the channel will be influenced by pH, water volume fraction, and cosolvent properties of the solution. Optimum OD4MI-CL efficiency is observed at pH 6.5 when 1-propanol, which has a low dielectric constant (epsilon = 20.8), is used as the NACE solvent in the separation channel. Water (epsilon = 80.1), the solvent in the ACE separation channel, acts similarly to a high dielectric constant organic solvent in NACE because the disadvantages normally associated with TCPO-CL reactions in water disappear due to the faster OD4MI-CL reaction versus OD4MI decomposition in aqueous solution. Therefore, it is expected that the OD4MI-CL detection system can be used in both NACE and ACE devices without requiring detector modifications. We also conclude that OD4MI-CL detection in NACE and ACE devices will be much more sensitive than the TCPO-CL detection used in current NACE devices.     

Amperometry with two polarisable electrodes-VII: chelometric determination of indium

Optimum conditions have been found for the chelometric determination of indium by biamperometric titration with EDTA. Two stationary platinum electrodes (Pt-Pt) or two graphite electrodes (C-C) may be used to indicate the end-point of the titration. At pH 1-1.5 the determination is highly selective. The applied potential only influences the absolute value of the current ; the accuracy of the determinations remains constant over a wide interval of applied potential. At a potential of 1.0-1.7 V the change of current during a titration with 0.05 M EDTA solution is of the order of 10 microA. Analytical applications of the method are discussed.     

高效毛细管区带电泳二肽类组分迁移行为的研究

本文考察了影响二肽类组分在高效毛细管区带电泳上迁移时间重复性的因素,提出了采用相对指标来作为高效毛细管区带电泳峰定性的依据,并考察了电流以及柱温对迁移时间和相对迁移时间的影响,发现在恒压lgt~m与T^-1有良好的线性关系;并从迁移时间的基本方程定量地解释了上述的变化规律.本文还发现,采用相对迁移时间指标后可以有效地消除操作电流以及柱温对迁移时间所引起的波动,是毛细管区带电泳的一个特征参数.     

四苯骈卟啉金属配合物轴向配位反应的热力学性质研究

金属卟啉在生命过程中起着重要的作用[1 - 4 ] 。CuTBP ,CoTBP与有机碱的反应,用光度法测定了轴配反应在不同温度下的速率常数和平衡常数,求得活化能及热力学参数,结果表明:它们与不同有机碱反应的活化能及平衡常数既与配体的碱性有关,也与空间位阻有关,同一温度下反应的平衡常数和速率常数的大小顺序均为:咪唑>吡啶>2 甲基吡啶>2 ,4 二甲基吡啶。1　实验部分1 .1　仪器与试剂日本产岛津UV 2 4 0G型分光光度计,上海分析仪器厂72 1型光度计(内装恒温套) ,重庆电机厂超级恒温槽。四苯骈卟啉金属配合物系自制[4] ,咪唑、吡啶、2 甲基吡…     

The synthesis and crystal structure of metal complexes S-alkyl-N-(ferrocenyl-1-methyl-methylidene)-dithiocarbazate and the study on their quenching the luminescence ofruthenium(bipyridine)_~3(2+)

The cobalt, nickel, copper, zinc and cadmium complexes of S-methyl-N-(ferrocenyl-l-methyl-methylidene)-dithiocarbazate (H-LSM) and S-benzyl-N-(ferrocenyl-l-methyl-methylidene)-dithiocarbazate (H-LSB) were synthesized and the crystal structure of Cd[Fe-C(CH3) = NNCSS. (CH3)]2 was solved by X-ray diffraction. The crystal is in the orthorhombic system with space group Pbca, cell parameters a=19.741(3), b=19.924(5), c=15.452(4) A, and the final factors of R=0.032. The study on quenching the luminescence of Ru(bpy)3 by those complexes showed that bimolecular quenching constants obtained from the Stern-Vohner constant and the excited-state lifetime were related to the redox potential of the quencher. Linear relationship is shown in the plot of logkq vs. E1/2(Q+/Q). The main factor which influences the quenching rate constant and the redox potential is the coordinating ability of the metal in the complex.     

Electrocatalytic determination of chlorpromazine drug using Alizarin Red S as a mediator on the glassy carbon electrode

The anodic oxidation of chlorpromazine (CPZ) has been studied on a glassy carbon electrode by electrocatalytic effect of Alizarin Red S (ARS) as a homogenous mediator in universal buffer (pH = 2). The linear sweep voltammetry (LSV) studies showed that the catalytic current of this system depends on the concentration of CPZ. The magnitude of the peak current for ARS increased severely in the presence of CPZ, and proportional to CPZ concentration. The catalytic peak current was linearly dependent on CPZ concentration in the ranges of 10–500 μM and the detection limit was 5.16 μM by LSV. The diffusion coefficient of CPZ was estimated using chronoamperometry. The method also was used for estimation of catalytic rate constant at catalytic reaction between ARS and CPZ. The influences of potentially interfering substances on the current response of the system were examined. The importance of technique is because of its ability to electrocatalytic determination of CPZ with ARS as homogenous electrocatalyst, while it does not need to be prepared as for the modified electrode. The method was successfully applied for analysis of CPZ in solid pharmaceutical formulations.