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171.
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The amounts of substances migrating from plastics into foodstuffs with high fat contents are in most cases higher than in foodstuffs with water contents. This increase in migration commonly is due to the higher solubility of the migrating organic compounds in fat compared to water. The increase in migration is not necessarily due to an increase in the substance's diffusion coefficient due to interactions between the fat and the plastic as is often assumed. Ethanol is a good simulant for fatty foods because it has little interaction with many plastics, e.g. polyolefins, migrants are readily soluble in it, and because it is easy to work with analytically. The utilizable limits of ethanol and ethanol/water mixtures as food simulants are developed from the physical background of diffusion. The use of ethanol and ethanol/water mixtures is supported by published experimental migration results. 相似文献
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Reinik O. O. 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1994,28(7):373-374
Power Technology and Engineering - 相似文献
176.
The use of differently processed soya bean as a major source of dietary protein was evaluated in a haematological study using broiler chickens in which groundnut cake (GNC), raw soya bean (RSB), roasted soya bean (RtSB), cooked soya bean (CSB) and soya bean oil cake (SBC) were fed on equi-protein basis. The results showed that: 1. Red blood cell (RBC) count and haemoglobin content of blood significantly (P less than 0.05) increased in chicks fed RSB relative to the other soya bean diets. Feeding differently processed soya bean significantly (P less than 0.05) influenced mean cell haemoglobin (MCH) and mean corpuscular volume (MCV) while the mean corpuscular haemoglobin concentration (MCHC) was not significantly influenced. 2. Both the total white blood cell (WBC) count and the monocytes were significantly (P less than 0.05) influenced by the dietary treatments. Chicks fed processed soya bean generally had higher number of monocytes. 3. Physical properties determined were specific gravity and erythrocyte sedimentation rate. The latter was significantly (P less than 0.05) lower in all the processed soya bean-fed chicks. 4. Minerals determined in blood were Na, K, Ca, Mg, Fe, Cu and P. Of all these, chicks fed RSB had significantly (P less than 0.01) lower levels of blood Mg and marked decrease in Ca. 相似文献
177.
In-circuit testing is commonly thought to be inefficient for a high level of quality control, and unable to match the high yields of functional testing. A quantitative study of 34,296 boards that represented the testing of 6,671,038 components reveals that in-circuit testing can produce high yields -96.9% in this case. The author looks at this study 相似文献
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Two approaches to the estimation of the sensitivity of explosives to external disturbances are proposed. One of them involves evaluation of the hazard of a particular technological operation in the production or processing of an explosive. The second approach defines a generalized risk factor for handling of the given explosive. Methods are discussed for estimating the average sensitivity. A classification of industrial explosives by their average sensitivity is given.Central Scientific-Research Institute of Chemical Machinery, Chernogolovka 142432. Translated from Fizika Goreniya i Vzryva, Vol. 30, No. 6, pp. 96–99, November–December, 1994. 相似文献
180.