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991.
Kinetics of the reaction of aquacobalamin (H2OCbl) with isoniazid (isonicotinic acid hydrazide, INH) in weakly alkaline, neutral, and weakly acidic media was studied using UV–Vis spectroscopy. It is shown that the reversible formation of a complex more stable than those of cobalamin(III) with pyridine and hydrazine occurs during the reaction. A mechanism of the reaction includes reversible stages of binding a neutral INH molecule by cobalamin(III) through an oxygen atom with its subsequent deprotonation, along with the reversible interaction of H2OCbl and the negatively charged form of INH.  相似文献   
992.
The fixation and activation of molecular oxygen on copper(II) complexes with 5-hydroxy and 5-aminoorotic acids, leading to oxidation of the ligand.  相似文献   
993.
Russian Journal of Organic Chemistry - New 1-(ω-chloroalkyl)isatins were synthesized by alkylation of isatin with α-bromo-ω-chloroalkanes. The reaction of 1-(3-chloropropyl)isatin...  相似文献   
994.
The peculiarities of the behavior, structure, and properties of low-molecular fluoropolymers (fluorooligomers), namely, industrial fluoroparaffins and derivatives resulting from the thermal processing of ultradisperse powders of FORUM® trademark, are studied. The results are obtained on the basis of the IR spectroscopic investigation of the products of pyrolysis of the fluorooligomers. The measurement data on rheological properties of the samples upon heating are analyzed.  相似文献   
995.
For supercapacitors with sulfuric acid electrolyte, a promising carbon material was suggested, namely, activated carbon from waste wood. It was shown how the synthesis conditions of activated carbon affect its porous structure and electrochemical characteristics of supercapacitors on its basis. The changes in the porous material under different synthesis conditions were controlled using the highly informative limited evaporation method, which allows us to obtain complete information about the porous structure of the micro- and mesopores of the material within a relatively short period of time. The negative effect of the excess volume of macropores in the electrode on the capacity and energy based on the dry mass of electrodes was shown experimentally and analyzed. The properties of the synthesized material were compared with those of other carbon materials. The best samples of the developed material possess a specific electric capacity of over 390 F/g.  相似文献   
996.
997.
Some facts of the theory of the Lorentz group are specified for looking at the problems of light polarization optics in the frames of vector Stokes-Mueller and spinor Jones formalism. In view of great differences between properties of isotropic and time-like vectors in Special Relativity we should expect principal differences in describing completely polarized and partly polarized light. In particular, substantial differences are revealed when turning to spinor techniques in the context of the polarized light.  相似文献   
998.
999.
The X-ray standing wave method has been applied to study the formation of protein-lipid film on the water subphase. The influence of different toxic reagents (heavy metals and urea) on protein-lipid interaction in an ordered film of glucose oxidase and behenic acid has been investigated. Analysis of angular dependence of fluorescence yield provided information on molecular arrangement in bioorganic nanosystems on the water surface, where protein and phospholipid molecules were free to move over the water subphase.  相似文献   
1000.
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