双电层相互作用时胶体表面电位的分布及电荷密度的计算

本文以实验为基础,运用计算机数值解解出双电层相互作用时平面胶体表面电位ψ随距离X的分布,依据作者导出的双电层相互作用时胶体表面阴离子负吸附方程,计算出胶体表面外Hclmhotz面(OHP)处的表面电荷密度σ_δ;讨论了双电层相互作用程度(ψ_d/ψ_δ)对胶体表面电位分布及其表面电荷密度的影响。     

粘土胶体表面双电层重叠时ψ_δ及ψ_d的计算

本文依据Gouy-Chapman双电层理论导出了描叙粘土胶体表面压电层重叠时对阴离子负吸附方程。以实验为基础,利用该方程通过计算机数值解解出粘土胶体表面外Helmhotz面(OHP)处的电位~ψδ和两粘粒之间的中点电位~ψd,并对所得结果进行了讨论。     

粘土胶体表面双电层重叠时ψδ及ψd的计算

本文依据Gouy-Chapman双电层理论导出了描叙粘土胶体表面压电层重叠时对阴离子负吸附方程。以实验为基础, 利用该方程通过计算机数值解解出粘土胶体表面外Helmhotz面(OHP)处的电位ψ_δ和两粘粒之间的中点电位ψ_d, 并对所得结果进行了讨论。     

电催化界面和反应的电化学阻抗谱研究：经典永不褪色

本文章综述了电催化领域电化学阻抗谱（EIS）的相关研究. 首先概述了从二十世纪初到现在这一专业领域的发展历史. 然后介绍了电催化阻抗理论的几个里程碑. 其中,着重介绍了目前分析电催化EIS数据的主流模型——Dolin-Ershler模型. 之后,具体讨论了铂金单晶的双电层电容,特别是围绕这一基础课题的实验和理论上的挑战. 我们质疑采用Dolin-Ershler模型获取稀溶液中双电层电容的合理性. 因为在稀溶液中,双电层效应使得双电层电容具有频散特性,因而双电层电容的低频部分在分析过程中可能被遗失了. 未来,我们期待看到新的实验去证明或反驳一个最近的理论预测,即铂电极在氧化物生成电位区域中具有非单调表面电荷关系和负双电层电容.     

电催化界面和反应的电化学阻抗谱研究:经典永不褪色（英文）

本文章综述了电催化领域电化学阻抗谱(EIS)的相关研究.首先概述了从二十世纪初到现在这一专业领域的发展历史.然后介绍了电催化阻抗理论的几个里程碑.其中,着重介绍了目前分析电催化EIS数据的主流模型——Dolin-Ershler模型.之后,具体讨论了铂金单晶的双电层电容,特别是围绕这一基础课题的实验和理论上的挑战.我们质疑采用Dolin-Ershler模型获取稀溶液中双电层电容的合理性.因为在稀溶液中,双电层效应使得双电层电容具有频散特性,因而双电层电容的低频部分在分析过程中可能被遗失了.未来,我们期待看到新的实验去证明或反驳一个最近的理论预测,即铂电极在氧化物生成电位区域中具有非单调表面电荷关系和负双电层电容.     

计算机控制电毛细曲线测量

电毛细曲线在双电层结构的研究中应用十分广泛。表面张力随电位的变化能给出电极表面电荷量及其符号的信息。在电毛细曲线的最高点，表面张力相对于电位的变化为零，因而为电极的零电荷电位。电极一溶液界面的许多性质与电位偏离零电荷电位的程度有关。电毛细曲线在电极表面吸附现象的研究中也是重要的手段。     

NaCl介质中盐浓度、pH对α－Al~2O~3表面相互作用力的影响

利用原子显微镜研究NaCl介质浓度及体pH值对氧化铝表面作用力的影响规律。发现较低的盐浓度下,相互作用表示为长程排斥力,双电层厚度的实际值与理论值较好地吻合,随NaCl介质浓度的提高,双电层压缩长程斥力减弱,测定了pHMH4.0变化到9.67的作用力曲线,发现当pH等于7/90时,两表面的相互作用表现为吸引力,通过恒电荷、恒电位拟合,发现氧化铝的等电点在pH8.2处,与Zeta电位的测定结果相一致。     

氧化铝／水界面上表面络合模型的参数

本文报道了由氧化铝的水悬浮液的电位滴定数据得到的扩散双层模型，恒定电容模型和三层模型的参数，即本征表面酸度常数，本征表面络合常数和双电层的电容，并用这些参数计算作为ｐＨ值和离子强度函数的表面电荷密度，表面电势和表面各组分的分布。     

硫酸溶液中Pt电极表面过程的EQCM研究

应用电化学循环伏安和石英晶体微天平(EQCM)方法研究了0.1mol·L-1硫酸溶液中Pt电极表面的吸附和氧化过程.从电极表面质量变化的结果分析,可认为正向电位扫描时氢区表面质量的增加是由于水分子取代Had引起的,而双电层区的质量增加则是由于水的吸附模式逐渐由氢端吸附转向氧端吸附所致.根据频率变化和电量数据,进一步推算出水在双电层区是以低放电吸附形式出现的,1molPt原子和水分子只发生0.054mol的电荷转移.本文结果可为认识Pt电极表面过程提供定量的新数据.     

以Co2＋掺杂纳米TiO2为光催化氧化剂的原位光致化学发光分析方法 研究及其应用

研究了Co2＋掺杂TiO2纳米粒子在光信号诱导下产生的超氧阴离子自由基在纳米粒子表面的吸附和解吸特性. 当以该纳米粒子为光催化氧化剂进行原位光致化学发光反应时, 光诱导产生的超氧阴离子自由基通过扩散穿过纳米粒子表面的双电层到达本体溶液, 与溶液中的化学发光试剂进行化学发光反应. 由于超氧阴离子自由基在纳米粒子表面的吸附、解吸和双电层效应, 使得光化学反应和其后的光生氧化剂的化学发光反应具有时间和空间的分辨特性. 将 Co2＋掺杂TiO2纳米粒子光致化学发光反应的特点与鲁米诺化学发光体系结合, 建立了一种原位光致化学发光反应的新方法, 并提出了一种基于纳米技术调控化学发光反应的新思路. 在最佳反应条件下, 该方法对格列本脲响应的线性范围为2.0×10－8～1.0×10－6 g•mL－1, 检出限为6×10－9 g•mL－1.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.