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61.
M. M. Krayushkin M. A. Kalik L. G. Vorontsova E. Yu. Zvezdina M. G. Kurella 《Russian Chemical Bulletin》1993,42(7):1204-1208
9-Methyl-3,3a,4,5-tetrahydro-6H-thieno[2,3-b]thiocino[4,5-c]isoxazole and 9-hydroxyimino-2-methyl-7-methylene-6, 7,8,9-tetrahydro-5H-thieno[2,3-b]thiocine have been prepared for the first time by the oxidation of 2--alkenylthio-3-thiophenecarbaldoximes with NaOCl. X-ray structural investigations of thieno[2,3-b]thiocine and 2-homomethallylthio-5-methyl-3-thiophenecarbaldoxime have been carried out.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1262–1266, July, 1993. 相似文献
62.
Shetty Kalidas Korus roger A. Crawford Dom L. 《Applied biochemistry and biotechnology》1989,(1):825-843
Glycine max was used as a model plant cell suspension culture to establish relationships among growth kinetics, phenolics production,
elicitor action, and peroxidase activity. Timing of elictor addition through monitoring of peroxidase provided an excellent
means of optimizing yields of phenolics and reduced the time span during which phenolics were formed, negating the need for
a secondary production medium. We have also determined that calcium and other cellular effectors like polyamines and organic
osmolytes, when used in conjunction with elicitors, enhance phenolics production. Calcium directly enhanced elicitation, whereas
polyamines and other osmolytes such as glycerol and proline extended cell viability. The study also demonstrated potential
for enhancing secondary metabolite production by a combination of elicitation, cell viability stabilizers, and by addition
of nutrients at the time of elicitation. 相似文献
63.
64.
65.
Henriques ES Floriano WB Reuter N Melo A Brown D Gomes JA Maigret B Nascimento MA Ramos MJ 《Journal of computer-aided molecular design》2001,15(4):309-322
We present the search for a new model of -factor XIIa, a blood coagulation enzyme, with an unknown experimental 3D-structure. We decided to build not one but three different models using different homologous proteins as well as different techniques and different modellers. Additional studies, including extensive molecular dynamics simulations on the solvated state, allowed us to draw several conclusions concerning homology modelling, in general, and -factor XIIa, in particular. 相似文献
66.
R. M. Zolotar' A. I. Bykhovets S. N. Sokolov N. V. Kovganko 《Chemistry of Natural Compounds》2002,38(1):66-69
The toxicity of steroids 1-11 for colorado beetle (Leptinotarsa decemlineata Say.) larvae was studied by contact-intestinal treatment. Active insect-growth regulators were found among the studied compounds. 相似文献
67.
The thermal degradation behaviors of some branched and linear polysiloxanes were studied by thermogravimetric (TG) analysis and infrared (IR) spectroscopy, and the effect of phenyl content on the thermal stability of the tested branched polysiloxanes was investigated. The branched polysiloxanes with phenyl obtain higher thermal stability at lower temperature. The degradation residues of the examined branched polysiloxanes at 800 °C are rather high, 65.1-77.6% in N2 and 40.5-66.5% in air, respectively. However, the amount of solid residue increases with decrease in phenyl content in both N2 and air atmospheres. It was found that the thermal stability of the branched polysiloxanes is higher than that of the linear one, which indicated that the branched structure benefits the formation of a crosslink in the solid residue. 相似文献
68.
69.
碳酸自由基、硝酸自由基、磷酸自由基和硫酸自由基是化学反应的重要中间体,都具有氧化性,对污染物在自然和人为环境中的迁移转化会产生重要的影响.文中较为详细地介绍这几种自由基的电极电位、产生方式、检测方法及与有机物的反应方式.总结四种自由基的特性及与有机物的反应方式可发现,四种自由基和羟自由基电极电位不同,导致它们和有机物反应速率的不同;碳酸自由基并不是羟自由基去除剂,对于一些容易被氧化的化合物,碳酸自由基氧化效果比羟自由基好;四种自由基均可由羟自由基转化而来,并且这四种自由基和羟自由基与有机物反应方式基本一致,都通过电子转移、夺氢和加成的方式进行.可以预测四种自由基和羟自由基降解有机物的机理将非常相似,今后应研究四种自由基与羟自由基相互转化的规律,以及与代表性有机物的反应机理. 相似文献
70.
M. Yoshida M. Asano M. Kumakura R. Katakai T. Mashimo H. Yuasa K. Imai H. Yamanaka 《Colloid and polymer science》1990,268(8):726-730
A sequential polydepsipeptide containing a tripeptide sequence L-alanyl-Lalanyl-ethyl L-glutamyl and an-hydroxy acid L-lactic acid, poly(Ala-Ala-Glu(OEt)-Lac), was synthesized to prepare the microspherical particles by the solvent evaporation process. In this case, the solvents play the most important role for the preparation of polydepsipeptide microspheres and, as an example, when 200 mg of the polydepsipeptide dissolved in 10 ml of 98/2% chloroform/dichloroacetic acid mixture was stirred at 400 rpm and 30 C, the microspherical particles with mean diameter of 58m were formed after pouring into 200 ml of 1% (w/v) poly(vinyl alcohol) solution. 17-Estradiol was incorporated into the particles, and the resulting particles were found to contain 5 mg of drug per 25 mg of the particle. The in vivo release of drug from the microspherical formulation was evaluated by measuring the pharmacological influence on rat prostate. It was found that the sufficient amount of drug, keeping the effective pharmacological influence, is supplied during the first 12-week period, followed by an incomplete supplying of drug intil the implant is perfectly degraded in vivo in the 25th week from the start of implantation. 相似文献