超声辐射下金属锰诱发芳香醛的还原偶联

在超声辐射下，Mn-NH4Cl-THF：H2O(1：4，V：V)或Mn-MnCl2-THF:H2O(1：4， V：V)体系中，于室温2-3h内可使芳香醛还原偶联成邻二醇，收率为30％-95％．与 传统方法相比，反应时间缩短，还原剂用量降低，产品收率提高．     

甲醇在欠电位沉积Ru修饰Pt电极上的催化氧化

采用欠电位沉积(upd)方法在Pt 表面沉积亚单层的Ru制备出upd-Ru/Pt 电极. 通过欠电位沉积前后电极在0.5 mol·L-1 H2SO4溶液中循环伏安图-152 - 128 mV(vs Ag/AgCl)电位范围内对氢区的数值积分确定Pt表面Ru 的覆盖度. 用电化学方法测试了甲醇在upd-Ru/Pt电极上的催化氧化, 并讨论分析了欠电位沉积电位和Ru的表面覆盖度对甲醇氧化的影响. 结果表明, Ru能够欠电位沉积到Pt表面. Pt表面欠电位沉积少量的Ru 即能大大促进甲醇的氧化.只要控制upd-Ru的沉积量, upd-Ru原子就能大大促进甲醇氧化而与沉积电位无关. Ru原子对甲醇氧化的促进作用与Ru和Pt是否形成合金无关, 而取决于Ru 在Pt表面的百分含量.     

Two New Sesquiterpenes from Eupatorium lindleyanum

Various germacrane sesquiterpenes have been isolated from many species of the Eupatorium.In recent years these compounds have been increasing interest due to their insecticidal,cytotoxic,antitumor-promoting and insect-antifeedant activities1.In our present study,we have investigated the chemical constituents of Eupatorium lindleyanum DC.,which is a geo-authentic medicine of Jiangsu province.It is used as a antipyretic drug.Two novel germacrane sesquiterpenes(Figure1)were found by us from th…     

STUDY ON THE SYNTHESIS AND PROPERTIES OF MACRORETICULAR IPN POLYACRYLAMIDE—POLY(VINYL—ETHYLENEDIAMINE)CHELATE SORBENTS

A new series of MR-IPN polyacrylamide—poly(vinyl-ethylenediamine)chelatesorbents were prepared by the reaction of ethylenediamine with MR-IPN matrixes.The newchelate sorbent showed good sorption properties for auric and platinic ions.     

Intrinsic Surface Reaction Constant in 1-pK Model of Mg-Fe Hydrotalcite-like Compounds

The relationship among intrinsic surface reaction constant (K) in 1-pK model, point of zero net charge (PZNC) and structural charge density (σst) for amphoteric solid with structural charges was established in order to investigate the effect of σst on pK. The theoretical analysis based on 1-pK model indicates that the independent PZNC of electrolyte concentration (c) exists for amphoteric solid with structural charges. A common intersection point (CIP) should appear on the acid-base titration curves at different c, and the pH at the CIP is pHPZNC. The pK can be expressed as pK=-pHPZNC log[(1 2αPZNC)/(1-2αPZNC)], where αPZNC≡σst/eNANs, in which e is the elementary charge, NA the Avogadro‘s constant and Ns the total density of surface sites. For solids without structural charges, pK=-pHPZNC. The pK values of hydrotalcite-like compounds (HTlc) with general formula of [Mg1-xFex(OH)2](Cl,OH)x were evaluated. With increasing x, the pK increases, which can be explained based on the affinity of metal cations for H^- or OH^- and the electrostatic interaction between charging surface and H^- or OH^-.     

DL－苹果酸－丙酮－BrO~3^-－Mn^2^+－H~2SO~4化学振荡 反应诱导期的新特征 及其动力学研究

在前文研究工作的基础上,较详细地研究了DL-苹果酸(以下简称DL-MA)、丙酮(以下简称Act)参与下的新型化学振荡反应及各种影响因素,对各主要参与反应物质在诱导期中的作用、起振原因、诱导期的新特征和可能反应机理进行了较为深入的研究,分别获得DL-MA,KBrO~3,MnSO~4的浓度对诱导期影响的拟合方程。以及诱导期的表观活化参数为E~I~N=68.50kJ·mol^-^1。     

Construction of a Novel 2D Polymer [Co（dmpzm）（dca）2]∞ from Reaction of a Mononuclear Complex [Co（dmpzm）Cl2] with Sodium Dicyanamide （dca） [dmpzm=bis（3,5-dimethylpyrazolyl）methane]

Reaction of COC12.6H20 with equimolar bis（3,5-dimethylpyrazolyl）methane （dmpzm） produced a mononuclear adduct [Co（dmpzm）Cl2] （1）. Treatment of 1 with sodium dicyanamide （dca） afforded a polymeric complex [Co（dmpzm）（μ-dca）2]∞ （2）. 1 and 2 were characterized by elemental analysis, IR spectra, thermogravimetric analysis and single-crystal X-ray diffraction. The cobalt atom in 1 adopts a distorted tetrahedral coordination geometry, bound to two N atoms of one dmpzm and two Cl atoms. Complex 2 has a 2D brick-wall network （extended along the bc plane） in which the { [Co（dmpzm）（μ-dca）]2} n^2n＋ chains are interconnected by pairs of μ-dca anions along the c axis. The magnetic properties of 1 and 2 were also investigated.     

诱导效应指数与脂肪族胺、醇和醚的气相碱性

用烷基诱导效应指数I和RX分子中质子亲合原子X所带电荷qx及元素电负性XN与 脂肪胺，醇、醚的气相质子亲合PA进行关联，结果表明，脂肪胺，醇、醚的气相碱 性可以用下式定量描述：PA(kJ.mol^-1)-2732.0333-2457.1510∑I-1492.2351qx- 732.6277XN利用上式对64种化合物的气相碱性进行预测，平均相对误差为0．34％ ，预测值和实验值的偏差均在实验误差范围内。     

Enhancement of Photocurrent Generation of a Novel Stilbazolium Dye Dimer in LB Monolayer Films

A novel dye dimer,bis-{[1-(N-hexadecyl-4-pyridinium)-2-(4-N,N-dimethylaminopheyl)] ethenyl} methane diiodide (C16BP) was synthesized,and the photoelectrochemistry of the dye Langmuir-Blodgett monolayer modified ITO electrode was investigated.For comparison,the photoelectrochemistry of the monomer (E)-N-hexadexyl-4-[2-(4-N,N-dimethylaminophenyl) ethenyl] pyridinium iodide (C16P) was also measured.The results show that the photocurrent generation property of the dimer is enhanced.The photocurrent generation quantum yield is 0.38% for C16BP,while that for C16P is 0.23%.     

含X-型液晶基元的液晶高分子的研究

以4,4′-(烷撑二酰氧)二苯甲酰氯和2,5-二羟基-1,4-苯撑双-(对乙氧基苯甲酸酯)为单体,采用低温缩聚方法,合成了含X-型液晶基元和不同柔性链长度的主链型液晶聚合物。聚合物的液晶行为用DSC、偏光显微镜和X-光衍射进行了表征。对于样品升温消光后又重新出现双折射的异常现象,初步认为是加热过程中分子量提高的结果。