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941.
Jan A. Derecki 《Journal of Great Lakes research》1985,11(3):201-207
Periodic man-made changes in the outlet of Lake Huron through the St. Clair River date back to the middle of the last century. These artificial channel changes have been well documented during the present century. They consist of dredging for commercial gravel removal in the upper river during 1908–25 and uncompensated navigation improvements for the 7.6-m (25-ft) and 8.2-m (27-ft) projects completed in 1933 and 1962, respectively. The total effect of these changes on the levels of Lakes Michigan and Huron (hydraulically one lake) and on the upper St. Clair River profile was determined with dynamic flow models. The ultimate effect of the above dredging was a permanent lowering of the Lake Michigan-Huron levels 0.27 m (0.89 ft), which represents a tremendous loss of freshwater resource [32 km3 (7.7 mi3)]. 相似文献
942.
Two questions formed the structure for examining the formal communication among researchers using the Journal of Consumer Studies and Home Economics (JCSHE) The first question pertained to the interrelationship between the literature published and cited in JCSHE. The second asked what impact the literature published in JCSHE had on authors publishing in other journals. By performing Bradford analysis using the 1,160 journal references cited by authors of 210 articles in the first seven volumes of JCSHE, 26 core journals were identified. JCSHE was ranked second because it was cited 54 times in 37 articles by 29 authors. Through citation analysis 17 citing articles published in 12 journals other than JCSHE were found. Seven of these 17 citing articles were published in other home economics journals. 相似文献
943.
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
944.
Economic ideas and processes are becoming increasingly integrated with more traditional engineering and hydrologic models
of water management problems. Combining economic management concepts and performance indicators with an engineering-level
of understanding of a hydrologic system can provide results and insights more directly relevant for water management decisions
and policies. When such models are developed and used with involvement of stakeholders, they can become a basis for shared
understanding of water problems as a foundation for negotiated management and policy solutions. When implemented with optimization
software, integrated hydro-economic models also can suggest promising innovative solutions for policy-makers to consider.
Their applications to river basin management problems are reviewed. Economic and integrated economic-engineering-hydrologic
modeling is then discussed in the context of the evolving European Water Framework Directive. Relevant items are cost recovery
and water pricing, cost-effectiveness of water management measures, and public participation in decision processes. 相似文献
945.
Soft sediments from the Detroit River were analyzed for the USEPA priority pollutants to generally characterize contaminant distribution. Forty-three were detected. Highest heavy metal concentrations were found in the Trenton Channel and immediately downstream of Grosse Ile. They ranged from an area mean (N = 2) of 0.19 mg/kg mercury to 338.7 mg/kg zinc (dry weight). Polynuclear aromatic hydrocarbons ranged from 0.1 mg/kg to 38.8 mg/kg (mean, N = 2) with the highest levels near Grosse Ile. PCBs ranged from 0.015 mg/kg to 1.7 mg/kg (mean, N = 2). Organochlorine pesticides were not detected except for a trace of heptachlor in one sample. Sediment contamination in the Detroit River is widespread with higher concentrations on the U.S. side downstream of the Rouge River and in the Trenton Channel. The significance of these in-place pollutants to biota and as a source to Lake Erie is still unknown. 相似文献
946.
947.
An assessment of hydrocarbon and metal/metalloids (arsenic, cadmium, copper, lead, mercury, selenium, zinc) contamination in sediments from Lake Mulwala, Australia, was undertaken. The objectives of the study were: (i) to determine the extent of contamination in the lake sediments, compared to Australian and international sediment quality guidelines, and (ii) to attempt to identify the contaminant sources to the lake. With the exception of a few samples containing elevated levels of arsenic and/or mercury, the levels of all contaminants in the sediment samples taken from the lake were below the ‘lower trigger’ of the Australian Sediment Quality Guidelines that would warrant further investigation. High molecular weight hydrocarbons (up to 700 mg kg−1) were found in most sediment samples. Non‐metric statistical analysis indicated that the contaminant distribution was different in different parts of the lake, with the lowest concentrations generally found at the influent to the lake. No definitive source(s) of contamination could be identified for either metalloids or hydrocarbons. 相似文献
948.
The use of valuation models that focus on lender criteria has been growing in the appraisal field. In the rush to build lender criteria into real estate valuation models, equity investor criteria, expectations, and requirements occasionally have been ignored. The specific criteria considered in this paper are the loan-to-value ratio and the debt coverage ratio for lenders and the equity dividend rate for equity investors. Each of these three criteria may be a binding constraint on value.
Graphical analysis provides a framework within which major real estate valuation models (i.e., Ellwood, McLaughlin, Gettel, Lusht-Zerbst, and Steele) are compared. A new valuation model (i.e., the Cannaday-Colwell model) is developed which utilizes the equity dividend rate.
The three definitional models (i.e., McLaughlin, Gettel, and Steele) are found to be relevant only by mere coincidence. Each of these models simultaneously considers two of the three key criteria, completely eliminating the possibility of consideration of anything else; i.e., the models become tautological.
It is shown that the discounted cash flow based models (i.e., Ellwood, Lusht-Zerbst, and Cannaday-Colwell) each tell one-third of the story. One of these models will be relevant depending upon whether the binding constraint is the maximum loan-to-value ratio, the minimum debt coverage ratio, or the minimum equity dividend rate. The relevant model is the one that yields the lowest value estimate of the three. 相似文献
Graphical analysis provides a framework within which major real estate valuation models (i.e., Ellwood, McLaughlin, Gettel, Lusht-Zerbst, and Steele) are compared. A new valuation model (i.e., the Cannaday-Colwell model) is developed which utilizes the equity dividend rate.
The three definitional models (i.e., McLaughlin, Gettel, and Steele) are found to be relevant only by mere coincidence. Each of these models simultaneously considers two of the three key criteria, completely eliminating the possibility of consideration of anything else; i.e., the models become tautological.
It is shown that the discounted cash flow based models (i.e., Ellwood, Lusht-Zerbst, and Cannaday-Colwell) each tell one-third of the story. One of these models will be relevant depending upon whether the binding constraint is the maximum loan-to-value ratio, the minimum debt coverage ratio, or the minimum equity dividend rate. The relevant model is the one that yields the lowest value estimate of the three. 相似文献
949.
2006年1月1日,新《公司法》正式实施.《公司法》作了许多修改以解决公司治理方面存在的突出问题,完善公司治理.一直为业界所诟病的内部人控制和关联交易等将会大大减少,中小股东和债权人的利益将会得到有效保护.在新〈公司法〉的指引下,中国公司治理显露出新的走向. 相似文献
950.