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111.
Summary There were studied the process of styrene polymerization in PVC swollen surface layer initiated by free radicals generated under the action of chemical potential gradient as an external force. It was found that conversion of styrene into the block copolymer is an diffusion controlled process.
Zusammenfassung Die Initiation des Prozesses der Polymerization von Styrol in den Oberflächenquellungsschichten von PVC wurde untersucht.Dabei wurde festgestellt, daß die freien Radikale, welche bei Zerreißung von spannungsbeanspruchten Bindungen, wie sie durch Einfluß von äußeren Kräften auf den Gradienten des chemischen Potentials des Quellungsmittels an Oberflächenquell bildungsmittel Polymer entstehen können, Polymerizationsprozesse des olefinischen Quellungsmittels initiieren können.


Dedicated to ProfessorV. Kellö in celebration of his 60th birthday.  相似文献   
112.
新显色剂对溴苯酚偶氮若丹宁光度法测定Au(Ⅲ)的研究   总被引:8,自引:0,他引:8  
提出了以显色剂对溴苯酚偶氮若丹宁[5-(5-溴-2-羟基苯偶氮)若丹宁]作为光度法测定Au(Ⅲ)试剂的新方法。在1.2mol·L~(-1)盐酸介质及阴离子表面活性剂十二烷基苯磺酸钠(SDBS)存在下,Au(Ⅲ)与试剂形成桔红色配合物,545nm处有最大吸收,摩尔吸光系数ε为7.75×10~4,Au(Ⅲ)浓度在0~44μg/25ml范围内服从比耳定律。方法灵敏度高,选择性好,配合物的稳定时间长,操作简便,已成功地应用于含金废水中Au(Ⅲ)的测定。  相似文献   
113.
本文介绍偏氯乙烯悬浮共聚树脂的优异阻隔性能、合成配方与工艺。  相似文献   
114.
The three-dimensional EHMO crystal orbital calculations for crystalline C60, Ca3C60, and Ca5C60 are reported. The ground states of both undoped solid C60 and partially doped Ca3C60 are found to be insulating with an indirect energy gap of 1.2 and 0.5 eV, respectively. In contrast, Ca5C60 forms a metallic conducting phase with a set of three half-filled bands crossing the Fermi level, which is found to be located close to a peak of the density of state. The character of crystal orbitals near the Fermi level for both Ca3C60 and Ca5C60 is completely carbonlike. In both cases, the Ca atoms are almost fully ionized and C60 molecules form a stable negative charge state with six to 10 additional electrons. © 1995 John Wiley & Sons, Inc.  相似文献   
115.
叙述了同步辐射白光全反射X射线荧光分析的实验装置,给出了几种标准物质TXRF实验的检出限,并对实验结果进行了讨论。  相似文献   
116.
Construction of tetrahydropyran rings has attracted a great deal of interests in organic synthesis in recent years1, since tetrahydropyran moiety constitutes a structural unit in a number of natural products2. In addition, tetrahydropyran derivatives possess wide range of biological activities and pharmacological properties, such as anticancer activity3 and antihypersensitivity4. Many methods for the preparation of such compounds have already been developed5. Among them, condensation of α, β…  相似文献   
117.
A number of 6(5H)-phenanthridinones have been conveniently prepared from 9-oxofluorenes through the Schmidt reaction. It has been found that all amino and nitro 9-oxofluorenes thus far tried gave substituted 6(5H)-phenanthridinones with the amino or nitro group situated in the benzene ring attached to the nitrogen of the lactam group. UV and IR spectral data are presented for these compounds.  相似文献   
118.
Wang XP  Pan JH  Li WH  Zhang Y 《Talanta》2001,54(5):805-810
The interaction of cyclodextrins with meso- Tetrakis (4-N-trimethylaminobenzyl) porphyrin (TAPP) in 0.1 mol l(-1) phosphate buffer (pH 7.0, 20 degrees C) has been studied by polarography. The TAPP can form the 1:1 inclusion complex with Sulfobutylether-beta-cyclodextrin (SBE-beta-CD) and1:2 inclusion complexes with other four cyclodextrins. A new expression, which is used to calculate the inclusion constant for1:2 inclusion complex by polarography, has been educed and testified firstly in this paper. Furthermore, the inclusion abilities of different kinds of cyclodextrins are compared. The result shows the inclusion ability of anionic cyclodextrin SBE-beta-CD with cationic porphyrin TAPP is very strong. It suggests that the charge attraction between CDs and TAPP plays an important role in the inclusion procedure except for the hydrophobic effect. The inclusion formation of anionic cyclodextrins with drugs can increase released rate of drugs at high pH; therefore, the suparmolecular data for the controlled release of the drugs that owned the similar properties as hematoporphyrin have been offered by polarography in this paper.  相似文献   
119.
A gas chromatographic method for monitoring diacetyl guanfubase A in plasma is described. The procedure involved a single solvent extraction of drug from rabbit plasma into ethyl acetate with guanfubase A as an internal standard. The extract was analyzed subsequently on a gas chromatograph equipped with a hydrogen flame ionization detector. The recovery was 86.43% +/- 6.90% (+/- SD); the RSD of within-day and between-day was 2.81%-5.26% and 5.22%-8.24%, respectively; the regression line was linear over the concentration range of 25-200 micrograms/mL, the limit of detection was 10 micrograms/mL. No endogeneous interference was found in chromatograms of the biological samples. This method was applied to the pharmacokinetic study of diacetyl guanfubase A in rabbits.  相似文献   
120.
Based on the development prospect of cosmetics industry, the advantage of light industry characteristic and the foundation of applied chemistry in Jiangnan University, a systematic upgrading of applied chemistry was carried out through "emerging engineering education (3E)" project "upgrade and practice of chemistry-related majors of local and/or trade university responding to the social developments" supported by the Ministry of Education. On the basis of investigation and analysis, the orientation and training goal of applied chemistry were updated first, and then the curriculum system was determined and the curriculum construction is strengthened, so as to achieve more distinctive characteristics, more solid foundation and more comprehensive quality. In view of the new requirements of the 3E for talent training, some practices have been formed in the aspects of multi-disciplinary integration, multi-angle coordination and close integration to industry. Contributing the development of cosmetics industry and seizing the commanding point of science and technology from the perspective of talent training, will play a unique role in human social progress.  相似文献   
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