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K. N. Anakhaev 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(9):586-592
Conclusion The presently existing methods or calculating seepage in inclined ASEs have a limited area of use and often give substantial deviations from the actual values. At the same time, no analytical relations are known for calculating Iex in the backwater zone of the LP. The formulas proposed in the article permit determining all main parameters of the seepage flow, including separately for the zones of effluent seepage and backwater of the LP, with an accuracy sufficient for engineering calculations.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 33–36, September, 1992. 相似文献
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Up to 30% of the released colour arising from bleached kraft pulp and paper production comes from the alkaline extraction stage. This waste stream can therefore be readily targeted to remove colour at source in mills where improved colour management is required. The efficacy of five advanced oxidative treatment and physico-chemical technologies in removing colour from a typical Eop stage effluent was compared. The most effective oxidative treatment was peroxymonosulphate (79% colour removal in 15 minutes). Ozone and TAML treatments removed 74% and 58% of colour respectively within 30 minutes. In comparison, hydrogen peroxide alone was only able to remove 35% of the colour over 4 hours. Coagulation with polyaluminium chloride achieved 89% colour removal within 5 minutes. However, this treatment produced an undesirable sludge, and may cause toxicity in the treated wastewater. Overall, colour removal ability of the five technologies ranked from highest to lowest was polyaluminium chloride > peroxymonosulfate > ozone > TAML > hydrogen peroxide. Other factors, such as operating costs, feedstock modification and capital infrastructure, also need to be taken into account when selecting the most suitable colour management option. 相似文献
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This paper examines the common stock returns of three groups of bidders that purchased brokerage houses. Only in the cases of horizontal mergers, one brokerage house purchasing another, are there abnormal returns associated with the purchase. Neither bank holding company bidders nor non-financial bidders gain significantly when purchasing a brokerage house. Bank holding company bidders face considerable regulatory delays, and these economic disturbances may eliminate their gains. Bank holding company expansion into these non-bank activities does not appear, at the time of announcement, to either hurt or benefit them; hence, this expansion does not appear to further the loss exposure of the Federal Deposit Insurance Corporation. 相似文献
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