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991.
As part of a study of the chemistry of the steam-stimulated recovery of heavy oils, the hydrolysis and subsequent desulphurization of tetrahydrothiophene and thiophene by aqueous solutions of vanadyl and nickel salts was investigated. Vanadyl sulphate and vanadyl chloride were shown to behave very differently, emphasizing that these salts have different molecular species in aqueous solutions. 相似文献
992.
Piryatinskii B. M. Sobolev B. A. Serebrinskii L. E. Kogan A. I. Deineko P. S. Obaturov I. V. 《Chemistry and Technology of Fuels and Oils》1970,6(7):488-491
Chemistry and Technology of Fuels and Oils - 相似文献
993.
L. Hernqvist O. Leissner B. Petersson 《European Journal of Lipid Science and Technology》1987,89(5):190-193
A new type of low erucic acid rapeseed oil containing high amount (11%) of palmitic acid (C16-LOBRA) was studied, both in labscale and in pilot-plant equipment. The polymorphic behaviour of fat blends and margarine emulsions consisting of C16-LOBRA, LOBRA and soybean oil and their hydrogenated fats were examined. The results clearly show the potential in the hydrogenated C16-LOBRA. The time before the stable ß-form is developed is much longer for the hydrogenated C16-LOBRA compared with the hydrogenated LOBRA and in fact similar to a hydrogenated soybean oil. The hydrogenated C16-LOBRA is therefore well suited to be used in e.g. margarine systems. 相似文献
994.
995.
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
996.
Various metal halides have been dispersed in high and low molecular weight, amorphous poly(propylene oxide), by solution blending techniques, to give single phase polymeric complexes which remained thermoplastic even at very high salt loadings. These complexes were amorphous and showed a single well-defined glass transition temperature (Tg) by differential thermal analysis with the Tg of the complex up to 140°C greater than the Tg of the parent polymer. The Tg elevation depended upon both the amount and the type of salt added and for a given salt the elevation followed a sigmoidal curve which levelled out at high salt concentrations. The Tg data have been interpreted in terms of a chelate ring model involving the co-ordination of two adjacent ether oxygen atoms in the polymer backbone to the salt. Using this model it was possible to consider the complex as a random copolymer consisting of complexed and uncomplexed monomer units. The contribution of crosslinking by metal salts to the elevation of Tg was assessed by studying poly(tetramethylene glycol)-zinc chloride complexes in which chelate formation is entropically unfavourable. Mechanical data are reported for ZnCl2 complexes with high molecular weight poly(propylene oxide). The results indicate that ZnCl2 increased the rubbery modulus and this has been interpreted in terms of ZnCl2 forming a few, weak intermolecular crosslinks. 相似文献
997.
998.
999.
H. R. Spiegel J. Juilfs U. Neubert K. J. Euler J. W. Beck D. Besdo H. Winter H. Becker W. Neuberger R. Jung K. Herfort H. Bühler H. Göppl H. W. Hahnemann W. Siegel 《Forschung im Ingenieurwesen》1970,36(2):64-68
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VDI 相似文献
1000.
A ‘tubeless syphon’ was used as an elongational viscometer for the purpose of measuring elongational viscosities of glass bead suspensions in dilute polymer solutions. It was found that while the shear viscosities increased, the elongational viscosities decreased very sharply with increasing bead concentration. The conclusions from the present data are then compared with the observed changes in the elastic properties of two phase molten polymer systems. A double shift procedure has been successfully adopted to correlate the experimental data. 相似文献