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991.
Summary The current article deals with the initial developments of the use of a continuous plug flow reactor using an original heterogeneous catalyst system for the living coordinated anionic polymerization of certain oxygenated rings. This reactor is designed in order to maintain the essential characteristics of the original batch system. One of the pertinent parameters considered here is the residence time of the reactants inside the reactor. The column has been used to investigate ethylene oxide and -caprolactone oligomerization. Initial experiments have pointed out how the molecular weights can depend on the flow rate for a fixed bed length. Some theoretical problems relative to the reactive column are discussed in order to investigate more in depth the properties of this original continuous process and to model it to find the optimal working conditions.  相似文献   
992.
Flavor and oxidative stabilities were studied by organoleptic evaluation and chemical analysis of three different samples of soybean oil: unhydrogented (I); hydrogenated with nickel catalyst (II); and hydrogenated with copper-chromium catalyst (III). Analyses for these oils were: I II III iodine Value 138 109 113 Linolenate, % 8.3 3.3 0.4 Each oil was deodorized with the addition of either citric acid alone or citric acid plus BHA and BHT antioxidants. Addition of antioxidants did not improve the flavor stabilities of the oils in accelerated storage tests but did improve the flavor stabilities of II and III in light exposure tests. All three oils that received the same additive treatment had equivalent flavor stability in both accelerated storage and light exposure tests. However, both hydrogenation and antioxidant treatment improved oxidative stability as measured by the Active Oxygen Method. There was good correlation between flavor score and the logarithm of the peroxide value determined at the time of tasting. Presented at the AOCS Meeting, New York, May 1977.  相似文献   
993.
994.
Total lipid and phospholipid contents of liver, skin and depot fat from yearling hen turkeys have been studied. Liver lipid averaged 88.5 mg/g wet tissue; skin, 385.0 and depot fat, 753.5. Phospholipids comprised 32.05% of total lipid of liver, but only 0.81% of skin and 0.46% of depot fat. Fatty acids of liver differed from those of skin or depot fat by larger amounts of 16∶0, 18∶0, 20∶4, 22∶0 and 24∶0, and smaller amounts of 16∶1, 18∶1, 18∶2, 18∶3 and 20∶0. Similarity existed between skin and depot fat. Journal Paper No. J-6473 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 1696.  相似文献   
995.
Thin layer chromatography was adapted for direct quantitative estimation of sucrose esters of palmitic acid. Urea-phosphoric acid spray was used to detect the sucrose moiety of the various esters. The photometrically metermined density density of each spot on the thin layer plate was found to be proportional to its sucrose content. Ester content was then obtained by multiplying sucrose found by the factor, mol. wt. ester/mol. wt. sucrose. Ester mixtures were prepared by interesterifying sucrose with various proportions of methyl palmitate in dimethylformamide solution. Positional isomers were observed at each level of substitution but could not be adequately separated from each other for quantitative evaluation. Presented at the AOCS Meeting, Minneapolis, October 1969. So. Utiliz. Res. Dev. Div., ARS, USDA.  相似文献   
996.
Temperature dependence of KIC values for Si3N4 bodies sintered at high pressures without additives was studied from room temperature to 1400°C. Little change in KK was found in this range.  相似文献   
997.
The matrix concept was used to characterize the chromatographic rules in the elution of molecular species of triglyceride. To prove the hypothesis experimentally, cacao butter, palm oil, linseed oil, olive oil, rapeseed oil and triglyceride of “Ogonori” (Gracilaria verrucosa) were examined. A matrix model was suggested to help determine the individual molecular species of naturally occurring triglycerides.  相似文献   
998.
999.
1000.

The 10th Five-Year Plan — A Five-Year Plan For Product Quality And Production Efficiency

The main task of the man-made fibre industry is to improve the quality of its products  相似文献   
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