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51.
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Ferric chloride leaching, at temperatures around 74°C, is found to remove up to remove up to 97% of the uranium from ores occurring in the Elliot Lake area of Canada. Radium removal is poor due to the formation of sulphates from the sulphides present in the ore. However, if the sulphides are removed initially by flotation, then ferric chloride can extract as much as 92% of the radium, giving tailings which are sulphide-free and with radium levels approaching 24 pCi/g. The main steps in a ferric chloride leaching process have been tested at the bench scale. Radium may be removed by adsorption on manganese dioxide and uranium is removed by liquid extraction with D2EHPA (DAPEX process). The ferric chloride may be recirculated for further leaching and the net usage is expected to be in the order of 5 kg/Mg of solids treated. Because of the recycle, it is possible to keep chloride ion levels in the effluent below the prescribed level of 750 mg/L. 相似文献
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Recent experimental results on determination of antenna pattern and power gain from near-field measurements are described. Two new antenna measurement theorems were applied. Measurements were made on an electrically large horn lens, a standard-gain horn and a nominal duplicate of the measuring antenna. Some comparisons with direct far-field measurement results were made. 相似文献
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Conducted 3 experiments to assess undergraduates' perceptual awareness of energy requirements in their immediate surroundings (e.g., refrigerators, automobiles, toasters). In Exp I, 48 Ss sorted 61 energy items (labeled on cards) into categories based on general similarity and similarity in terms of energy consumed in an hour of continuous use. Cluster analysis revealed that items were grouped according to function and size but not by energy requirements. In Exp II, 24 Ss rank ordered 19 household appliances according to energy consumption and volume. The judged order of energy consumption matched the actual order (watts/hour) moderately well, but significant deviations from accuracy occurred for items whose perceived volume appeared to exert an influence on perceived energy consumption. Some large objects were seen to require high energy even though their actual consumption is relatively low. Similarly, small objects were thought to consume small amounts of energy even though the opposite is true. Parallel results were obtained in Exp III (20 Ss) with the method of numerical magnitude estimation. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
This paper deals with the design of a project management game, intended to help project managers and team members acquire some of the necessary understanding for success in this field. The training needs of project managers are contrasted with the training potential of management games in general and some important factors in game desigt are discussed.The game simulates a project which is described in terms of a network. The player is presented with a sequence of ‘project meetings’ at which he must make certain decisions. The outcome of each decision will affect the total cost of the project. The game has been successfully run using a small project designed to test its capabilities. It is concluded that the game, in its working state and with a proved expansion potential, demonstrates that a satisfactory training aid for project managers can be produced. 相似文献
58.
W Chalupa B Vecchiarelli DT Galligan JD Ferguson LS Baird RW Hemken RJ Harmon CG Soderholm DE Otterby RJ Annexstad JG Linn WP Hansen FR Ehle DL Palmquist RG Eggert 《Canadian Metallurgical Quarterly》1996,79(5):800-812
Beginning at wk 5 of lactation, 136 cows (34 per treatment) were supplemented daily for 38 wk with 0, 10.3, 20.6, or 41.2 mg of recombinantly derived bST monomer. Cows were obtained from University of Kentucky, University of Minnesota, University of Pennsylvania, and The Ohio State University. Nine cows (4 at 0 mg/d, 1 at 10.3 mg/d, 1 at 20.6 mg/d, and 3 at 41.2 mg/d) did not complete the experiment because of health problems. Data from these cows were included in the reproduction and health databases but not in the production database. Cows supplemented with bST produced more milk, consumed more feed, had lower rates of BW gain, and had improved efficiencies of milk production (conversion of feed and NEL to milk). Additional increases in productivity were modest at 20.6 and 41.2 mg/d versus productivity at 10.3 mg/d of bST. Concentrations of fat, protein, and TS in milk were unaffected. At 10.3 mg/d, bST did not adversely affect reproduction or health. 相似文献
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Baird Anne Dull; Ausman James I.; Diaz Fernando G.; Dujovny Manuel; Adams Kenneth M.; Shatz Mark W. 《Canadian Metallurgical Quarterly》1988,56(1):148
[Correction Notice: An erratum for this article was reported in Vol 56(4) of Journal of Consulting and Clinical Psychology (see record 2008-10691-001). The authors' names were incorrectly ordered. The correct order is as follows: Anne Dull Baird, Kenneth M. Adams, Mark W. Shatz, James I. Ausman, Fernando G. Diaz, and Manuel Dujovny.] Neuropsychological and life-quality changes were studied 6 months after carotid endarterectomy, superficial temporal artery to middle cerebral artery bypass, multiple revascularization, and vertebrobasilar revascularization procedures. These changes were compared with those in patients with recent severe spinal complaints and in patients for whom revascularization was considered but not elected. Subjects were enrolled prospectively. We did not see statistically significant differences in neurobehavioral gains in patients undergoing cerebral revascularization versus those considered but not selected for surgery and versus patients with spinal complaints. Small sample size, marked intragroup variability, and lack of randomized subject assignments may have obscured modest-to-moderate treatment effects in some individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献