Electrical potential oscillation in an anionic surfactant system with barbitone in octanol as an oil phase

Studies were made on oscillations across a liquid membrane consisting of an oil layer, octanol containing barbitone, between two aqueous layers: one containing 8 mM SDS with alcohol and the other containing 0.1 M NaCl. The effects of various concentrations of chemical components in this system on the patterns of electrical oscillation were examined. The oscillations may be explained by the mechanism of repetitive formation and destruction of monolayer structures of the dodecyl sulfate anion at the interface between the organic and the aqueous phases, with the effect of proton penetration. This study of potential oscillation across a membrane containing a drug provides the possibility of further investigations in pharmacological activity.     

相转移催化合成增塑剂BBP和水杨醛的研究

相转移催化合成增塑剂ＢＢＰ和水杨醛的研究郭锡坤，高文华，曾东宇（汕头大学化学系，汕头５１５０６３）关键词相转移催化，季铵盐，聚乙二醇，邻苯二甲酸丁苄酯，水杨醛，增塑剂邻苯二甲酸丁苄酯（增塑剂ＢＢＰ）是一种优良的增塑剂．邻羟基苯甲醛（水杨醛）不仅是重要...     

Determination of trace amounts of iron by catalytic-adsorptive stripping voltammetry

A highly sensitive and selective voltammetric procedure is described for the determination of trace amounts of iron. The procedure is based on the adsorptive collection of an iron-thiocyanate-nitric oxide complex on a hanging mercury drop electrode. The adsorbed complex catalyzes the reduction of nitrite in solution, which gives a detection limit of 40 ppt iron (30 s accumulation). The stripping current increases linearly with iron concentration up to 80 ppb. The relative standard deviations are 4.2% and 1.6% at 0.5 ppb and 40 ppb respectively. Most of the common ions, except cobalt, do not interfere with the determination of iron. The procedure is applied to determine iron in biological samples, natural waters and analytical-grade chemicals.     

A Novel Plasticizer for the Preparation of Thermoplastic Starch

TPS was a biodegradable material based on starch. Starch was an inexpensive and natural renewable polysaccharide, which was widely investigated as the substitute of petroleum-derived plastics. Native starch commonly existed in granule structure with about…     

6291型热变形温度和维卡软化温度测试仪的校准及故障排除

介绍6291型热变形温度和维卡软化温度测试仪的温度校准和位移校准方法，对测试仪的一些常见故障，例如电源故障，主温度传感器故障，电加热系统控制单元故障及测试站的温度偏差较大等进行了分析，并给出了排除故障的方法。     

Syntheses of (-)-TAN-2483A, (-)-massarilactone B, and the fusidilactone B ring system. Revision of the structures of and syntheses of (+/-)-Waol A (FD-211) and (+/-)-Waol B (FD-212)

The structure of waol A has been revised from 1 to 6, the vinylogue of TAN-2483A (5). Aldol reaction of hydroxybutanolides 13b,c with 2,4-hexadienal affords 12b,c, which are subjected to iodoetherification with bis(sym-collidine)IPF6 to provide 11b(c). Treatment with Et3N in CH2Cl2 completes the three-step syntheses of TAN-2483A (5) and waol A (6). Aldol reaction of hydroxybutanolide 31 with 2,4-hexadienal affords 32, which is subjected to iodoetherification to provide 34, which in turn is treated with Bu3SnCl, NaBH3CN, and oxygen to provide diol 60. Further elaboration completes the first syntheses of massarilactone B (7) and the fusidilactone B (9) ring system.     

Aqueous p-nitrotoluene oxidation induced with direct glow discharge plasma

A plasma induced degradation process has been studied to treat 4-nitrotoluene (4-NT) present as an aqueous pollutant. The plasma was locally generated from a glow discharge around a tip of a platinum anode in an electrolytic solution. The influence of initial pH and Fe²⁺ on the degradation was examined. Major intermediates resulting from the degradation process were identified. Amongst the aromatic intermediates, p-hydroxybenzoic acid was the predominant degradation product. The formation of oxalic acid, malic acid was also observed. The final products of degradation were NH ₄ ⁺ , NO ₃ ⁻ and CO₂. Based on the analysis of intermediates and the kinetic considerations, the degradation was shown to follow a pseudo-first order reaction hence, a possible reaction pathway was proposed.     

Study on the Phase Diagram of CsCl-CeCl3-HCl(11%)-H2O System and the Properties of the Compounds

The equilibrium solubility of CsCl-CeCl3-HCl(11%)-H2O qua-ternary system at 25℃ has been determined by the physicchemical analysis method ,and the phase diagram was plotted, Two new double salts 3CsCl.CeCl3.3H2O and CsCl.CeCl3.4H2O obtained from the complicated system were identified and characterized by XRD,TG-DTA ,DSC,UV and fluorescence spectroscopy, Studies on the fluorescence excitation and emission show that 3CsCl.CeCl3.3H2O and CsCl.CeCl3.4H2O have upconversion luminescence of infrared-visible range,and the upconversion emission intensity increases with the increase of ratio of CeCl3 in CsCl.     

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.     

The evolution of morphology of ordered porous TiO2 films fabricated from sol-gel method assisted ZnO nanorod template

Ordered porous TiO₂ films, including TiO₂ nanotube arrays, are fabricated by a sol-gel dip-coating approach via ZnO nanorod templates obtained from aqueous solution approach. The results indicate that the morphologies of ordered porous TiO₂ films have been great affected by the sol-gel dip-coating cycle number. Open-ended TiO₂ nanotube arrays can be obtained in optimum dip-coating cycle numbers. The TiO₂ nanotubes with the inner diameter matching well with the diameters of ZnO nanorods, are well assembled and separate each other. When the cycle number is less than this optimum value, no intact porous TiO₂ film can be obtained. As the cycle number is larger than this optimum value, an ordered porous TiO₂ film with many throughout holes is formed. The evolutive mechanism of ordered porous TiO₂ films is proposed.