化学水浴法沉积 CdS 多晶薄膜

介绍了用化学水浴法沉积ＣｄＳ的方法。ＳＥＭ、ＸＲＤ以及透射光谱等分析表明，沉积在玻璃片上的ＣｄＳ膜，均匀、透明、密实，适合制作太阳电池窗口材料。同时简述了ＣｄＳ膜生长、生成的化学过程和机理。

MEDIATORLESS HYDROGEN-PEROXIDE ELECTRODE BASED ON HORSERADISH-PEROXIDASE ENTRAPPED IN POLY(O-PHENYLENEDIAMINE)

A mediatorless H2O2 sensor based on coelectropolymerization of horse radish peroxidase (HRP) and o-phenylenediamine (o-PD) is described. The electrode responds to H2O2 in a few seconds and gives a current density of 73.3 nA 1 mu mol(-1) cm(-2) at -100 mV

RADIATION STABILITY OF PTFE IRRADIATED UNDER VARIOUS CONDITIONS

As a typical example of a polymer degraded by radiation, the radiation stability of PTFE was observed to depend upon irradiation conditions. Increases in irradiation temperature and crystallinity were found to increase its radiation stability whereas increase in the concentration of oxygen in the system over a certain range was observed to have little effect on radiation-induced reactions of PTFE as measured by changes in number-average molecular weight, melting temperature and crystallinity.

PLASMA POLYMERIZATION OF OCTAFLUOROCYCLOBUTANE AND HYDROPHOBIC MICROPOROUS COMPOSITE MEMBRANES FOR MEMBRANE DISTILLATION

In this paper, hydrophilic microporous cellulose nitrate membranes have been surface-modified by plasma polymerization of octafluorocyclobutane (OFCB). The microporous composite membranes with a hydrophilic layer sandwiched between two hydrophobic layers have been obtained. The obtained composite membranes have been used in a membrane distillation (MD) process and have exhibited good performance. The effects of polymerization conditions, such as glow-discharge power and deposition time, on the structures and MD performances of the obtained composite membranes have been investigated by SEM, X-ray microscopical analysis, and XPS. The polymerization conditions should be as mild as possible in order to prepare the hydrophobic composite membrane with good MD performance. The typical MD behaviors of the obtained hydrophobic composite membranes are in agreement with that of hydrophobic membranes directly prepared from hydrophobic polymeric materials, like PVDF, PTFE, or PP.

论科技学术期刊稿件录用率的调控

科技学术期刊的稿件录用率是当前影响期刊出版时滞的关键因素之一.稿件录用与否和录用率的高低当由编辑部根据论文质量和期刊特点来全面衡量和确定.提出调控录用率和出版时滞的指导原则和具体方法.认为对论文进行全程质量控制,降低录用率而增加单位空间的有效信息量,可使科技期刊取得稿源充分而出版时滞又短的双赢.

ELECTROCATALYTIC OXIDATION OF ASCORBIC-ACID AT A PRUSSIAN BLUE FILM MODIFIED MICRODISK ELECTRODE

The preparation and the behaviour of a Prussian Blue (PB) film on a platinum microdisk electrode has been described. Electrocatalytic oxidation of ascorbic acid has occurred at the PB film modified microelectrode. This shows a typical example of a modified microelectrode in electrocatalysis following our previous theoretical studies (J. Electroanal. Chem., 309 (1991) 103) and the related catalytic reaction rate constant was determined.

THE CATALYTIC BEHAVIOR AND REACTION-MECHANISM OF THE BI-CE-O SYSTEM CATALYSTS IN THE OXIDATIVE DEHYDROAROMATIZATION OF PROPYLENE

Oxidative dehydroaromatization of propylene was investigated by the pulse technique over two kinds of single oxide catalysts. With the Bi2O3 catalyst, the main dimer product was 1,5-hexadiene, and the dimerization activity was stable to pulse number even if the catalyst was partly reduced to the bulk. With the CeO2 catalyst, benzene was mainly formed instead of 1,5-hexadiene, but the activity decreased rapidly with increasing pulse number, indicating that only the lattice oxygen near the catalyst surface could be used for oxidative dimerization and the further aromatization. The Bi-Ce-O system catalyst was found in this study to give higher aromatization activity and showed better stability, compared to the Bi-Sn-O catalyst. Although the Bi-Ce-O catalyst was only a mixture of the two component oxides from X-ray diffraction analysis, there was a significant combination effect on the selectivity to benzene. The highest and the most stable selectivity of benzene was obtained at Bi/Ce = 1. In the TPD spectrum of Bi-Ce-O catalyst, there are not only the lattice oxygen (beta-oxygen) over 620-degrees-C due to the reduction of Bi2O3, but also a great deal of the alpha-oxygen desorbed about 400-degrees-C, which is considered the absorbed oxygen in the bulk. This absorbed oxygen could probably be a compensation of the lattice oxygen through the route of gaseous --> absorbed --> lattice oxygen in the binary catalyst system. By the kinetic study on the Bi-Ce-O catalyst, the dimer formation rate was the first-order with respect to the partial pressure of propylene and zero-order of oxygen. Although detail investigation would be made further, it was considered that the complete oxidation of propylene would mainly take place parallelly on some different sites, and the rate-determining step of propylene dimerization occurred probably between an adosrbed propylene and a gaseous one by an Eley-Rideal type mechanism.

衬钽管石墨炉中分子背景的调查

调查了钾、钠、钙的化合物在热解管(PGT)和衬钽管(TaT)中的分子背景。结果表明,衬钽管对NaCl、KCl、CaCl_2、Ca(NO_3)_2的背景吸收均具有明显抑制作用。

抗氧剂和应力对EPDM/CIIR并用胶热氧老化性能的影响

研究了抗氧剂1010和2246及压缩应力对第三单体为双环戊二烯(DCPD)的乙丙橡胶/氯化丁基橡胶(EPDM_D/CIIR)和第三单体为乙叉降冰片烯(ENB)的乙丙橡胶(EPDM_B)/CIIR两种并用胶热氧老化性能的影响。认为抗氧剂能显著改善EPDM_D/CIIR的力学性能和热氧老化性能,压缩应力能影响EPDM_E/CIIR的使用寿命。

低温等离子体对聚乙炔稳定性的影响

70年代初,Shirakawa与宾夕法尼亚大学研究小组合作,发现用五氟化砷或碘掺杂的聚乙炔具有较高的金属电导性,聚乙炔作为一种新型的高分子导电材料,由于具有导电率高、比重轻、耐腐蚀、合成简单、原料便宜等一系列其它材料无从比拟的优点,而引起人们广泛关注。 聚乙炔作为一种新型导电材料,虽然具有上述优点,但由于其空气稳定性较差,而限制了