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991.
During the past decade, research by industry and government has developed numerous new chemical markets for fats and oils
derivatives. Lower prices for competitive raw materials have forced some of these new products into specialty markets. Economic
factors, such as the continual growth of the chemical industry, population increases, and high consumer demand, have allowed
for steady growth in the fat-derivative market. New fat-type plasticizers are currently consuming about 60 million pounds
of fats annually. Synthetic lubricants will probably be consuming 20 million pounds of fatty diesters annually by 1965. Animal
feeds consume approximately 600 million pounds of fats and fat derivatives annually and may eventually become the leading
domestic nonfood market for fats. The protective coating market as an outlet for fats continues to decline, and the continuing
shift to nonfat materials and changes in pain formulas indicate that, while the demand for protective coatings may increase,
the use of fats in their manufacture may not share in the increase. Nonfat chemical raw materials provide intense price competition
for fatty raw materials. Fat prices are influenced by the demand for use in food, soap, paints, and possibly animal feeds
rather than by the demand for use as chemical raw materials.
Presented before the American Oil Chemists' Society, New York, October, 17, 1960. 相似文献
992.
The thermal decomposition of europium hydroxide in an air atmosphere was investigated by means of weight-loss measurements, infrared spectroscopy, X-ray diffraction analysis, and electron microscopy. These studies showed that EU(OH)° decomposed at temperatures between 225° and 300°C into EuOOH, which was stable up to about 425°C. Between 435° and 465°C this compound decomposed into cubic Eu2 O3 , which was stable until its inversion to the high-temperature monoclinic form. X-ray diffraction data were collected for Eu(OH)3 and EuOOH and showed that the trihydroxide has a hexagonal crystal structure and the oxyhydroxide is possibly orthorhombic. The Eu(OH)2 , EuOOH, and cubic EunOa powders contained particles up to several microns in size consisting of agglomerates of crystallites in the size range 200 to 400 A. The single monoclinic Eu2 O3 sample studied contained crystallites whose average size was greater than 2000 A. 相似文献
993.
The concept of volume averaging is used to theoretically study the mechanisms of mass dispersion, adsorption, and dead-space volume. These mechanisms are important to the understanding of miscible surfactant flooding. After simpiffication based on order-of-magnitude scaling, a linear core model is solved using state variable finite-difference techniques. Mass dispersion and adsorption are shown to be important model parameters while dead-space volume is a rather insensitive model parameter. 相似文献
994.
The melting points (Tm) were measured for oligomers obtained by a direct continuous esterification process between terephthalic acid and ethylene glycol. Multiple regression analyses of data were carried out, and an equation was obtained for predicting melting points with correlation coefficient of ~0.99. 相似文献
995.
TiO2 was sintered in HCl atmospheres to enhance the effects of vapor transport. Little or no densification is observed for temperatures between 1000° and 1300°C. Particle coarsening occurs at temperatures above 1200°C. The apparent activation energy for particle growth is 114 kJ/mol. It is concluded that the primary mass-transport mechanism is vapor transport while the particle growth rate is limited by grain-boundary mobility . 相似文献
996.
997.
Gel permeation chromatography and thin layer chromatography have been used respectively to separate and characterize the first seven members of an epoxy resin polymer homologous series on a preparative and analytical scale. The epoxy resin was formed by the reaction between Bisphenol-A and epichlorhydrin. NMR was used to identify the oligomers. The relationship between extinction coefficient and degree of polymerisation was also determined. 相似文献
998.
999.
W. Stein H. Weiß O. Koch P. Neuhausen H. Baumann 《European Journal of Lipid Science and Technology》1970,72(11):956-959
Preparation of Esters of α-Sulfo-Fatty Acids A process for the continuous α-sulfonation of saturated fatty acid esters with SO3 was worked out and a special bleaching process was developed for these products. The conversion, i. e. the degree of sulfonation is of the order of 95–99%. Solvents, further processing steps or purification operations for the separation of by-products are not required. 相似文献
1000.
R. Marquard W. Schuster H. Klein 《European Journal of Lipid Science and Technology》1979,81(10):381-389
Yield as well as Contents and Composition of Fats and Proteins in Several Varieties and Types of Mustard at Distinctly Different Ecological Locations In a cultivation experiment extending over two years the yield of different varieties of Brassica juncea, Brassica nigra and Sinapis alba was examined. Fat content and protein content were determined and the correlations with different characteristics were calculated. Fatty acid composition of the oil showed that erucic acid content was distinctly influenced by the location and the year of cultivation. In all samples, whose erucic acid content showed large difference from average values for the variety, electrophoretic patterns of the proteins were found to be distinctly different, both with respect to number and distribution of the bands. 相似文献