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971.
The reaction of H atoms (produced by nanosecond pulse radiolysis) with ferri-cytochrome-c in aqueous solution results in the second order formation of an absorption spectrum due to the addition of H atoms to the enzyme protein. This spectrum is not specific to the iron moiety. The rate constant of the addition is 1×1010M?1 sec?1. This is followed by two first order intramolecular processes with specific rates of ~ 1×105 sec?1 and ~ 2×104 sec?1. In these processes, specific spectra related to the α and β bands of ferro-cytochrome-c appear. The results are interpreted to show reduction equivalent transfer through the protein to the iron moiety. 相似文献
972.
N. Schönfeldt 《Journal of the American Oil Chemists' Society》1968,45(2):80-82
The course of the lime soap-dispersing action of various surfactants has been examined by use of a titrimetric method. Two
types of dispersants can be distinguished. With the addition of a surfactant of the first type, the concentration of the dispersed
fatty acid increases gradually. If a surfactant of the second type is used, a definite increase of the fatty acid concentration
first occurs after the addition of considerable amounts of the dispersant.
Ethylene oxide adducts and sodium triethylene glycol monolauryl ether sulfate behave like dispersants of the first type whereas
sodium dodecylbenzenesulphonate and sodium lauryl sulfate belong to those of the second type. The dispersing action of both
types of surfactants is discussed. 相似文献
973.
V. M. Lupéiko P. V. Umrikhin P. N. Dé'yachkov V. A. Perepelitsyn 《Refractories and Industrial Ceramics》1967,8(1-2):125-128
Conclusions A laboratory installation for flame guncreting was designed, built, and tested. A method was developed for flame guncreting of basic refractories. The guncreted layer obtained as a result of flame guncreting is formally bonded with the refractory, and in its density and structure, is significantly better than it.Translated from Ogneupory, No.2, pp.54–57, February, 1967. 相似文献
974.
L. B. Khoroshavin P. N. D'yachkov A. K. Purgin N. K. Pisarenko E. P. Kosolapova L. Ya. Pivnik V. K. Bogatikova A. K. Latysheva 《Refractories and Industrial Ceramics》1970,11(5-6):395-398
Conclusions The type of orthophosphoric acid has the maximum influence on the properties of corundum concretes, a lower influence on high-alumina concretes, and practically no influence on quartz-clay concretes. It is desirable to use wet-process orthophosphoric acid for refractory concretes. The excellent properties of concretes in the system A12O3-SiO2 based on this acid which is also cheaper enabled us to recommend it for preparing refractory concretes.The advantage of using H3PO4 of various types for corundum concretes is determined by the requirements placed on them in actual working conditions.Translated from Ogneupory, No.6, pp. 58–61, June, 1970. 相似文献
975.
976.
Summary Coordination polymers were synthesized using N,N'-Bis (carboxymethyl) dithiooxamide (NN' CMDTO) and Zinc(II) salts. The complexes were characterized by elemental analyses, IR spectral studies, TGA and viscosity measurements. In the proposed structures the ligand was supposed to be coordinated to metal through sulphur and oxygen. 相似文献
977.
Koptelov V. N. Pospelova E. I. Maryasev I. G. Spesivtsev S. V. Novikov E. P. 《Refractories and Industrial Ceramics》2002,43(1-2):22-25
Thermomechanical and chemical-ceramic properties of the PTMS basic-composition mixture for the consumable refractory lining of intermediate ladles in service at the Kombinat Magnezit Joint-Stock Co. are considered and some details of the fabrication technique are discussed. Results for the mixture tested for performance at various metallurgical plants are given. Advantages of the mixture for practical application, its microstructural characteristics in pre- and post-service conditions, and the wear behavior are discussed. 相似文献
978.
979.
980.
V. A. Perepelitsyn A. S. Freidenberg I. N. Sorokin 《Refractories and Industrial Ceramics》1976,17(1-2):104-106
Conclusions It was established that the crust forming on the lining of the blast-furnace stack can be divided into two genetic varieties, viz., mass-exchange and metallurgical crusts.The formation of a mass-exchange crust on the stack lining must be prevented by constructing the lining of high-density, thermally and chemically stable refractory minerals. At the same time it is advantageous to create conditions which favor the formation of a protective metallurgical crust on the surface of the lining.Translated from Ogneupory, No, 2, pp. 39–42, February, 1976. 相似文献