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81.
Comparison of nutrient cycling in a surface-flow constructed wetland and in a facultative pond treating secondary effluent. 总被引:1,自引:0,他引:1
There is a growing interest in the possibilities offered by combinations of waste stabilisation ponds (WSP) and constructed wetlands (CW). The purpose of our study was to compare treatment performances and nutrient cycling in a surface-flow wetland (SFW) and in a WSP treating secondary effluent. In the period between 2000 and 2003, a pilot SFW and a pilot WSP were constructed at the outlet of the wastewater treatment plant and their performance monitored while both were active under the same conditions. The SFW was planted with Phragmites australis and Eichhornia crassipes, while in the WSP development of algae was spontaneous. Performance efficiency was monitored by means of evaluation of physical and chemical parameters in water, by measurement of plant productivity and by analysis of N and P contents in biomass. The SFW with macrophytes proved more efficient in decreasing the suspended solids (64.6%), settleable solids (91.8%), organic N (59.3%), total N (38%), COD (67.2%) and BOD5 (72.1%) than the WSP. The WSP with algae was more efficient in treatment of ammonia nitrogen (48.9%) and ortho-phosphate (43.9%). The results of this study provide data that are of help in optimising combinations of SFW and WSP. 相似文献
82.
In the presence of foreign factor ownership tariffs change not only the terms of (goods) trade but also income flows between countries. Assume that only the home country owns factors abroad. Then the optimal tariff is negative if and only if foreign factor ownership entails trade-pattern reversals. Trade-pattern reversals are neither a necessary nor a sufficient condition for a negative optimal tariff if the foreign country owns factors in the home country. Changes in the home country's tariff shift the foreign country's offer curve. This adds a new dimension to optimal tariff analysis. 相似文献
83.
84.
The channel literature has paid little attention to issues related to exclusive dealing governance arrangements. Consequently,
there is only limited knowledge about how exclusive dealing impacts various channel processes and outcomes. This gap is especially
regrettable since exclusive dealing, in addition to being one of the most commonplace governance formats within the distribution
channels, is also one of the best exemplars of viable unilateral governance formats. In this initial investigation, the authors
explore the linkages among the constructs of exclusive dealing, relationalism, communication, and performance. Empirical data
for the study were drawn from the photocopier industry.
He obtained his M.B.A. and D.B.A. degrees from Boston University. His primary research interest includes channels of distribution,
franchisor-franchisee relationships, and consumer purchase behavior in international contexts. He has published articles inJournal of Marketing Channels and the proceedings of several marketing conferences.
This article was crafted when Rajiv Dant was at Boston University. He received his M.B.A. from Bombay University and his Ph.D.
from Virginia Polytechnic Institute and State University. His research focuses on channels of distribution, with primary emphasis
on franchise structure, franchisee-franchisor relationships, and public policy aspects of franchising growth and ownership
topics. His research has been published inJournal of Marketing, Journal of Public Policy & Marketing, Research in Marketing, Journal of Retailing, Journal of Business
Research, Journal of Business Venturing, Journal of the Operations Research Society, Marketing Letters, Journal of Small Business
Management, Journal of Economic Psychology, Southern Business & Economics Journal, Philosophical and Radical Thought in Marketing,
Journal of Healthcare Marketing, Journal of Marketing Channels, andInternational Small Business Journal. 相似文献
85.
86.
87.
The paper seeks to evaluate the evidence on the employment effectsof the collective working-time reductions in Europe over thepast 20 years. While theoretical analyses produce contradictoryassessments, most empirical studies show positive employmenteffects but take insufficient account of these conditions underwhich the reductions in working time were implemented. Theseconditions for the success of collective working-time reductionsinclude an active training policy designed to minimise skillshortages in the labour market, the modernisation of work organisation,wage increases in conjunction with productivity gains and amore equal income distribution. 相似文献
88.
G. H. BURROWS 《Abacus》1994,30(1):50-64
The extent to which allocated common costs should influence business decisions remains controversial in management accounting. In the finance and investment literature this issue is generally ignored or dismissed by appeals to the'incremental' principle. This article presents an historical analysis of allocations in long-run investing and pricing decisions. It is demonstrated that seminal figures in the development of both investment and price theory were conscious of the need for firms to cover common costs and generally favoured some form of allocation. The anti-allocationist position is shown to be of relatively recent origin and to have caused an inconsistency in the management accounting literature in the treatment of common costs. European costing theory is shown to have been consistently allocationist. Evidence of a return in the recent U.S. literature to the older Anglo-American, and continuing European, allocations tradition is presented. 相似文献
89.
Trends in Hydrological Parameters of a Southern Brazilian Watershed and its Relation to Human Induced Changes 总被引:5,自引:1,他引:4
Moraes Jorge M. Pellegrino Giampaolo Q. Ballester Maria V. Martinelli Luiz A. Victoria Reynaldo L. Krusche Alex V. 《Water Resources Management》1998,12(4):295-311
The Piracicaba river basin is a subtropical watershed located in the southeastern region of Brazil. With an area of 12 400 km2, the basin is a typical example of new landscape resulting from development in tropical and sub-tropical regions: establishment of intensive industrial and agricultural processes were followed by significant population growth and water management. This scenario has led to significant increase in water demand and decrease in water quality. The main objective of this study is the detection of changes in the patterns of flow and precipitation in the basin, and its possible relation to man-induced changes. Statistical analyses were performed on records of precipitation, evapotranspiration and streamflow, from 1947 to 1991. Precipitation and evapotranspiration totals showed significant increasing trends for the entire basin. From eight streamflow gauge stations, half showed significant decreasing trend. The most probable cause of such trends is the export of water from the basin to the metropolitan region of São Paulo city. 相似文献
90.
Our examination of the cross-section of expected returns reveals economically and statistically significant compensation (about 6 to 9 percent per annum) for beta risk when betas are estimated from time-series regressions of annual portfolio returns on the annual return on the equally weighted market index. The relation between book-to-market equity and returns is weaker and less consistent than that in Fama and French (1992). We conjecture that past book-to-market results using COMPUS-TAT data are affected by a selection bias and provide indirect evidence. 相似文献