Polyamine polymers from active hydrogen compounds,formaldehyde, and amines

Active hydrogen compounds such as hydroquinone (HQ), cyclohexanone (CH), acetophenone (AP), and 4,4′-methylene bis-N-methylaniline (MNA) polymerized with formaldehyde (F) and secondary diamines to produce Mannich base polyamine polymers. The HQ-containing polymers were oxidized to benzoquinone (BQ)-containing polymers and their redox properties were investigated in the desulfurization of hydrogen sulfide.     

Microdetermination of fluorine in organic compounds by oxygen flask combustion and conductometric titration

For the conductometric titration of fluoride with calcium acetate, solvent system in sample solution and titrant, concentration, and acidity of sample solution were examined to establish the titration conditions. Results of these examinations were transferred to the microdetermination of fluorine in organic compounds using oxygen flask combustion method.Comparative examination between quartz and Pyrex flasks for the combustion of fluorine samples indicated that good results were obtained by the use of the former flask, whereas the use of the latter one gave negative values of 1.0–1.6% due to the formation of boron fluoride during the combustion.     

氢部分选择性催化还原NO反应研究

在低钯含量活性非均布Pd/Al2O3催化剂上，实现了富氧条件下，氢部分选择性催化还原NO过程，低温、富氧条件下NO的转化率高达80％－100％。NO直接分解实验表明，600℃，NO分解转化率在无氧时为17．3％，有0．5％氧存在时接近于0。氢非选择性还原NO条件下，100℃以下，NO转化率为100％。根据实验结果及文献，推测了氢部分选择性还原NO过程中可能存在的反应，不同的反应温度下，NO脱除反应有所不同。在115℃以下，NO还原产物为NH3；115℃－155℃，NO还原产物为NH3、N2O和N2；155℃以上，NO还原产物中无NH3存在。NO还原反应与氢氧反应是平行的竞争反应。     

Generation and reactivity of bis(2,6-diethylphenyl)germanium(II)

The title intermediate ($\text{3a}$) is produced on photolysis of hexakis(2,6-diethyl-phenyl)cyclotrigermane ($\text{1}$) or bis(2,6-diethylphenyl)bis(trimethylsilyl)germane ($\text{4}$) as evidenced by trapping experiments, and thermally dimerizes to tetrakis(2,6-diethyl-phenyl)digermene ($\text{2a}$). Diarylgermylenes such as $\text{3a}$ do not form stable triethylamine adducts (e.g. $\text{5a}$) as has been previously reported.     

The Mechanism on Cyclization, Debenzylation and Oxidation of 1-[1-（Benzyloxy）-3-methylnaphthalen-4-yloxy]propan-2-one

Mansonone compounds represent a series of naturally occurring o-quinones mainly isolated from the heartwood of Mansonia Altissima1 and Ulmus Glabra2. Mansonone F contained oxaphenalene skeleton which was a relatively novel structure and rarely existed in …     

烟酸对酸性硫酸盐体系铜电沉积的影响

对溶液A: 0.8 mol•L－1硫酸铜,0.6 mol•L－1硫酸,5.0×10－5 mol•L－1氯离子,1.0×10－4 mol•L－1聚乙二醇的溶液,溶液B:在溶液A中加入2.0×10－2 mol•L－1烟酸,pH为0.5,运用循环伏安和计时安培法研究玻碳电极上铜的电沉积行为.结果表明,铜的电沉积过程经历了晶核形成过程,其电结晶按瞬时成核和三维生长方式进行.烟酸的加入对铜的电沉积具有阻化作用,但不改变铜的电结晶机理.沉积层的X射线衍射表明Cu为面心立方结构,在烟酸存在下沉积层出现(220)高择优取向,这可能是烟酸在Cu(220)晶面上发生强烈吸附作用的结果.     

SYNTHESIS, CHARACTERIZATION, METAL-UPTAKE BEHAVIOR OF BIS（BENZIMIDAZOLE） RESIN SUPPORTED ON EPOXIDE POLYMER

The new chelate resins, abbreviated as PNBMZs and PBBMZs based on epoxide polymer, were synthesized by polycondensation of N,N-diglycidyl-4-glycidyloxyaniline or 1,4-bis（2,3-epoxypropyl）benzene with the primary amine group of 1,3-bis（benzimidazol-2yl）propylamine （BBPAH）. The ion exchangers contain 2.71-3.23 mmol of the ligand contents per gram of the resin. Batch extraction capacities were determined for the metal chloride salts in buffer solutions in the pH range from -1 to 6.0. The chelate resins were very selective for Cu^2＋, Zn^2＋, Cd^2＋ in the presence of other divalent transition metal ions. The maximum uptake capacities of PNBMZ （synthetic molar ratio = 1：1.5） under non-competitive condition were found to be 0.94 mmol/g for Cu^2＋ at pH = 2, 1.3 mmol/g for Cd^2＋ at pH = 1 and 1.75 mmol/g for Zn^2＋ at pH = -1 respectively. While in the case of PBBMZ, it was 1.39 mmol/g for Cd〉 at pH = 1. The metal-uptake behaviors for both of them showed strong pH dependence, and their extraction capacities increase with decreasing pH. The uptake of Cu^2＋ by the resin PNBMZs at pH = 1 was found to be rather fast with t1/2 = 18 min. Metal-uptake experiments under competitive conditions also confirm that the chelate resins have a high selectivity for Cu^2＋, Zn^2＋, Cd^2＋ and the contrary pH dependence.     

配位聚合物{[Co(μ-4,4′-bpy)(4,4′-bpy)2·(H2O)2]·(4,4′-bipy)·(H2O)4·(OH)3·(Me)4N}n的晶体结构及性质

配位聚合物通常是通过某种有机配体与金属的配位几何选择以及无限网络的拓扑结构控制而形成的具有无限结构的化合物 [1] ,其结构新颖并具有不寻常的光电效应、非线性光学性能、磁性、超导及催化等诸多具有诱人应用前景的独特性能 .因此 ,近年来倍受化学家和材料学家的重视 [2～ 5] .以 Co为配位中心的配位聚合物若具有八面体构型 ,在一定条件下具有自旋转换能力 ,而且往往可与光电转换能力相关联 ,是一种潜在的新型信息存储材料 [6 ] .对于配位聚合物的形成 ,配体的选择最重要 . 4,4′-联吡啶及其衍生物是一种较好的刚性配体 ,相关的配位聚…     

Two New C—21 Steroidal Glycosides from Cynanchum aurichulatum

Two new C-21 steroidal glycosides, cynanauriculoside I and cynanauriculoside Ⅱ, were isolated from the roots of Cynanchum aurichulatum. Their structures were established using spectroscopic methods including one and two-dimensional NMR.     

Excited states of porphyrin isomers and porphycene derivatives: a SAC-CI study

Excited states of free-base porphyrin isomers, porphycene (Pc), corrphycene (Cor), and hemiporphycene (hPc), were studied by the Symmetry-Adapted Cluster (SAC)/SAC-Configuration Interaction (CI) method. The absorption peaks of the porphyrin isomers were assigned on the basis of the SAC-CI spectra. The X, Y, X', and Y' bands of the porphyrin isomers, which have weak intensities, are identified. The differences in the Q-band absorptions among the isomers were clearly explained by the four-orbital model. In Cor and hPc, the wave function of the B-band corresponds to the mixture of the four-orbital excitations and the optically forbidden excitation of free-base porphin (P), due to the molecular symmetry lowering in the isomers. The B-band character is described by the five-orbital model in Pc and the six-orbital model in Cor and hPc. Two tetrazaporphycenes and two ring-extended (dibenzo) porphycenes were designed, and the Q-band transition moment was successfully controlled. These examples show that the control of the four-orbital energy levels is the guiding principle for pigment design in porphyrin compounds.