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211.
Optimum Design of Sewage Sludge Consolidation Tanks 总被引:1,自引:0,他引:1
Consolidation is potentially the most cost-effective of all sludge treatment processes. However, traditional design procedures have been oversimplified such that the process has not generally been fully exploited.
The objective of this report is to summarize the Water Research Centre (WRc) procedure for sizing sewage sludge consolidation tanks, and explain the major design aspects which control the effective operation of the plant. The procedure provides a means of sizing tanks to consolidate any particular sewage sludge to any solids concentrations up to the maximum, and is applicable to both the batch and continuous operational modes. To obtain the predicted performance, the essential equipment such as the picket fence and control system, comprising a consolidation plant, must be suitably designed. 相似文献
The objective of this report is to summarize the Water Research Centre (WRc) procedure for sizing sewage sludge consolidation tanks, and explain the major design aspects which control the effective operation of the plant. The procedure provides a means of sizing tanks to consolidate any particular sewage sludge to any solids concentrations up to the maximum, and is applicable to both the batch and continuous operational modes. To obtain the predicted performance, the essential equipment such as the picket fence and control system, comprising a consolidation plant, must be suitably designed. 相似文献
212.
Squamous odontogenic tumour is a benign odontogenic tumour composed of a well-differentiated squamous epithelium immersed in a fibrous connective tissue stroma. It is a rare tumour and a recent literature review yielded only 36 cases. Two cases of squamous odontogenic tumour are presented, 1 located in the maxilla and the other in the mandible: 1 of these cases showed a periodontal involvement. The radiographic picture was fairly characteristic in 1 case, with a radiolucent lesion between the roots of the second mandibular premolar and the first molar, while, in the other case, it was possible to observe the presence of a lesion located at the apex of a molar. The tumours were enucleated, and no recurrences were observed after 5 years. 相似文献
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214.
R Hajdu R Thompson JG Sundelof BA Pelak FA Bouffard JF Dropinski H Kropp 《Canadian Metallurgical Quarterly》1997,41(11):2339-2344
MK-0991 (L-743,872) is a potent antifungal agent featuring long half-life pharmacokinetics. The pharmacokinetics of MK-0991 administered intravenously to mice, rats, rhesus monkeys, and chimpanzees is presented. Unique to MK-0991 is its consistent cross-species performance. The range of values for the pharmacokinetic parameters were as follows: clearance, 0.26 to 0.51 ml/min/kg; half-life, 5.2 to 7.6 h; and distributive volume, 0.11 to 0.27 liters/kg. The level of protein binding of MK-0991 was determined to be 96% in mouse and human serum. The compound exhibited high affinities for human serum albumin and at least two lipid components. The rationale for the selection of MK-0991 as a drug development candidate was based on its two- to threefold superior pharmacokinetic performance in chimpanzees over the performance of an otherwise equivalent analog, L-733,560. Once-daily dosing for MK-0991 is indicated by a graphical comparison of levels in the circulations of chimpanzees and mice. In a study of the pharmacokinetics of MK-0991 in mouse tissue, the organs were assayed following intraperitoneal administration. The area under the concentration-versus-time curves (AUC) segregated the tissues into three exposure categories relative to plasma. The tissues with greater exposure than that for plasma were liver (16 times), kidney (3 times), and large intestine (2 times). The exposure for small intestine, lung, and spleen were equivalent to that for plasma. Organs with lower levels of exposure were the heart (0.3 times that for plasma), thigh (0.2 times), and brain (0.06 times). Kinetically, drug was cleared more slowly from all tissues than from plasma, indicating that terminal-phase equilibrium had not been achieved by 24 h. Thus, some measure of accumulation is predicted for all tissues. Single daily doses of MK-0991 should provide adequate systemic levels of fungicidal activity as a result of its long half-life pharmacokinetics, wide distribution, and slowly accumulating concentrations in tissue. 相似文献
215.
J.F. Lyness BSc MSc PhD CEng MICE MIStructE W. R. C. Myers BA BSc PhD CEng MICE J. B. Wark BEng PhD 《Water and Environment Journal》1997,11(5):335-340
Flow measurements have been taken for steady and unsteady flows on a reach of a river having a compact compound channel. The 'single channel', 'divided channel' and 'lateral' distribution methods have been used to calculate conveyances for use in a one-dimensional unsteady flow model of the reach. Comparisons with measured flows show that the divided channel method and the lateral distribution method both underestimate floodplain flow depths. The lateral distribution method gives the closest accuracy in the relative depth range 0.15 ≤ Yr < 0.40. For large flow depths the single channel method becomes more accurate and slightly over-estimates flow depths.
The accuracy of unit width discharge distributions, calculated from the lateral distribution method are assessed by comparison with observed distributions for overbank flows. 相似文献
The accuracy of unit width discharge distributions, calculated from the lateral distribution method are assessed by comparison with observed distributions for overbank flows. 相似文献
216.
The Environment Agency has a statutory duty to secure the proper use of water resources, which is now considered inter alia to include an economically efficient allocation of resources as far as is possible within the current legislation. This paper considers the practical extent to which water rights can be traded within the existing system of regulation as a means of (a) improving the economic efficiency of resource allocation, and (b) satisfying customer demand for additional supplies. Outline proposals are also made for deregulation of current legislation to encourage further trading through less restrictive regulation. 相似文献
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218.
This paper deals with the problem of fast recognition of harmonic distortions by means of a wavelet transform. A method of fast detection of a frequency band affected by the high-frequency content and time of its occurrence is described. It is based on the auxiliary waveform distortion band factors (DBFs) calculated on the basis of wavelet coefficients. The merits of the presented method, as well as its limitations, are described on the basis of real voltages registered in ships' electrical power systems. This method is a part of the method based on the complementary application of Fourier and wavelet transforms, which was described in the previous papers of the author. However, this paper describes new research results and an expanded analysis exclusively focused on the aforementioned DBFs. 相似文献
219.
220.