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111.
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Ellagic acid (2, 3, 7, 8‐tetrahydroxy(1)benzopyrano(5, 4, 3‐cde)(1)benzopyran‐5, 10‐dione) was selected as a model pollutant which is present in the tannic fraction of cork processing wastewater. The ultrafiltration of aqueous ellagic acid solutions through three membranes was studied in tangential UF laboratory equipment. Two of the membranes were polyethersulfone (Biomax10K and Biomax5K, with MWCO of 10000 and 5000 Da, respectively), and the third made of regenerated cellulose (Ultracel5K, with MWCO of 5000 Da). The water hydraulic permeability was evaluated for each membrane. The evolution of the permeate flow rate with processing time was followed, and the influence of the main operating variables (feed flow rate, trans‐membrane pressure and nature of the membranes) on the permeate flux was also established. According to the hypothesis of the film theory, the intrinsic and apparent rejection coefficients, as well as the mass transfer coefficients, were also determined, and the values obtained were discussed as a function of the operating conditions used. 相似文献
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Networkable Windows-based operating system devices present information security challenges to both vendors and users of such devices. This article highlights some of those threats and offers measures to improve the link between a firm's business strategy, its operational activities, and its information security strategy. 相似文献
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S I Barr 《Progress in food & nutrition science》1987,11(3-4):307-361
Given the heightened interest in nutritional aspects of exercise, and an increase in athletic participation by women, it appeared timely to review the nutritional implications of exercise in women. The initial part of this paper contains a compilation of published studies on the nutrient intakes of female athletes. These reveal that most groups of athletes have adequate nutrient intakes, and that their vitamin and mineral intakes appear to be superior to those of nonathletic women. The average energy intake of athletes in studies summarized in this paper was 2069 kcal, and for certain groups of athletes, energy intakes were even lower. How these women manage to train intensely while consuming energy intakes similar to those of sedentary women is not readily apparent, and for this reason, the remainder of the paper discusses energy balance as affected by activity. Methodological considerations related to assessment of the components of the energy balance equation (food intake, energy expenditure, and body energy stores) are presented, with a focus on considerations in women. The effects of activity on each of these components are then discussed in an attempt to determine whether some form of energy conservation may occur. Finally, effects of activity on the menstrual cycle are reviewed. The observed changes are discussed in relation to nutrition 1) in terms of how nutrition may play a role in their causation; and 2) in terms of their nutritional implications for the amenorrheic athlete, specifically as regards energy balance and bone density. 相似文献
118.
The results of the synthesis of ceramic pigments using coprecipitation of hydroxides and difficultly soluble salts of multivalent
metal ions are described. The specifics of the coprecipitation process and the effect of various factors on the production
of the initial precipitates for subsequent synthesis of ceramic pigments are analyzed. The technology of pigment production
is described.
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Translated from Steklo i Keramika, No. 6, pp. 37 – 39, June, 2005. 相似文献
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120.
The study suggests improvements in the design of new houses to conserve energy and enhance indoor thermal comfort. Summer temperature records show that a new house has an average indoor temperature of 35°C with the ambient average 31°C. The traditional house in the old city recorded 28°C for the same period. Winter temperatures in both types of houses were similar (12°C) when not occupied. Architectural features of the two houses were compared to identify those responsible for difference in the thermal performance. Larger exposed surface and window areas, higher overall heat transfer coefficient and weaker thermal coupling with the ground for the new houses seems to contribute to their inferior thermal performance. 相似文献