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1.
The Constant Rate Thermal Analysis method has been used under different experimental conditions to obtain barium titanate powder of very small grain size. Both a crystallographic and a dielectric study ham been carried out on samples sintered at different temperatures. It is deduced that the formation of small coherently diffracting domains is improved by the generation of oxygen vacancies and the cubic phase stabilization depends on the coherently diffracting domain size rather than on the particle size.  相似文献   
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A nitrogen balance study, comparing a low-cost soy-oats infant formula with and without supplemental methionine, was carried out with infants of ages 3 - 26 months at a single equivalent level of nitrogen intake (approximately 850 mg/kg/day). Nitrogen retention was found to be unaffected by methionine supplementation. Com- parison of data obtained in this study with previous research re- vealed that a critical value for intake of total L-sulfur amino acids apparently exists in infants 3 - 26 months of age, below which methionine supplementation will increase nitrogen retention, but above which it will not. This value appears to coincide with that of 49 mg/kg/day recommended for infants by the FNB.  相似文献   
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Heating curves for different locations inside cans of mussels brine, placed in vertical, horizontal and inclined positions, were experimentally determined. Temperature profiles were fitted the response of a second order system to a step input. The location of the slowest heating point was established by comparison of the time constants. The critical heating point was found to be on the axis at one eighth the height of the cans when they were in a vertical position.  相似文献   
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The development of video applications for digital multimedia has highlighted the need for indexing tools, enabling the access to meaningful segments of video. The high cost of manual indexing creates a demand for the development of automatic algorithms, able to extract such indices with little intervention. In this paper we present new editing model–based algorithms that automatically extract low–level features in a movie: camera shots and camera motion. Rules of film making are used to derive higher-level elements, such as shot-reverse shot sequences. The algorithms have been tested on 20 h of movies and comparison with techniques in the literature is provided.  相似文献   
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Cottonseed/soybean blends (50/50) were ground in an Alpine pin mill with or without previous cooking in a Brady low-cost extruder. Free gossypol decreased with increasing amount of water added prior to extrusion and number of passes through the extruder. Available lysine increased with decreasing amount of added water but was unaffected by number of passes through the extruder. Type of soybean raw material utilized had no effect on free gossypol. Blends prepared from defatted cottonseed meal, however, had lower free gossypol than those made from cottonseed kernels. A blend similar to full-fat soy flour but of lower cost was prepared from unextruded 50% defatted cotton-seed meal/50% extruded soybean flakes, without added water, and ground in the Alpine mill.  相似文献   
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A low cost powdered infant formula made from soybeans, oats and sucrose, fortified with methionine, vitamins and minerals, has been developed. A dry process for making the formula, which employs a low-cost Brady extruder, has also been developed. The resulting product is of good microbiological quality and disperses readily in water to give a milk-like suspension of satisfactory stability to settling. The essential amino acid pattern of the formula, its PER and NPU values, nitrogen balance data with infants, proximal chemical analysis, calorie distribution and low level of trypsin inhibitor indicate it to be adequate for feeding infants 3 months or older. Clinical trials with infants also showed that the formula was well accepted and tolerated, and produced adequate weight gain. Retail prices of the product, packed in cans and polyethylene bags, are appreciably lower than those of comparable cow's milk and other soya-based infant formulas available in the market. The product is currently being manufactured and sold in several parts of Mexico.  相似文献   
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