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91.
J Byrne S Kienzle D Johnson G Duke V Gannon B Selinger J Thomas 《Water science and technology》2006,53(10):327-334
Long-term trends in alpine and prairie snow pack accumulation and melt are affecting streamflow within the Oldman River Basin in southern Alberta, Canada. Unchecked rural and urban development also has contributed to changes in water quality, including enhanced microbial populations and increased waterborne pathogen occurrence. In this study we look at changing environment within the Oldman River Basin and its impact on water quality and quantity. The cumulative effects include a decline in net water supplies, and declining quality resulting in increased risk of disease. Our data indicates that decreases in the rate of flow of water can result in sedimentation of bacterial contaminants within the water column. Water for ecosystems, urban consumption, recreation and distribution through irrigation is often drawn from waterholding facilities such as dams and weirs, and concern must be expressed over the potential for contaminate build-up and disproportionate potential of these structures to pose a risk to human and animal health. With disruption of natural flow rates for water resulting from environmental change such as global warming and/or human intervention, increased attention needs to be paid to use of best management practices to protect source water supplies. 相似文献
92.
A. S. Nekrasov S. A. Voronina V. V. Semikashev 《Studies on Russian Economic Development》2008,19(2):136-144
The current progress of electrification in Russia is clearly insufficient compared with G8 countries. At the same time, economy sectors have a high potential for energy saving. The electricity consumption of households depends on their cash income and the growth rate of electricity tariffs. 相似文献
93.
This paper focuses on the development of a theoretical scheme describing the transformation of primary incomes into end consumption and savings in the Russian economy. This scheme is basically a system of interrelated tables reflecting the distribution of primary incomes across the institutional sectors and their further reallocation and use. The scheme makes allowances for the specific features of the Russian economy and existing statistics. In terms of methodology, it is coordinated with the interindustry balance in current buyer prices and, from the theoretical standpoint, describes the connection between Quadrant II and Quadrant III of the balance. Therefore, the proposed system of tables is treated in the paper as Quadrant IV of the interindustry balance. The theoretical scheme is used by the authors as a necessary basis for constructing an empirical model of the relationship between value added and end product, which will be published in the next issue of this journal. 相似文献
94.
Doing qualitative field research in management accounting: Positioning data to contribute to theory 总被引:2,自引:0,他引:2
In this paper we argue that theory, method, methodology, and knowledge gains in qualitative field studies are intertwined through the ongoing hypothesis development in the field. We develop our argument through a discussion of specific qualitative field studies in management accounting. We emphasise in particular the distinctive role of theory in qualitative research as relating to expression of a subjective reality more than clarification of an objective one. In considering this subjectivity we discuss the ways in which the doing of qualitative research brings to bear discipline on the researcher allowing us to assess the trustworthiness of their accounts. The intention is to develop a more appropriate basis for judging the plausibility of qualitative field studies than notions borrowed from positivistic methodology. 相似文献
95.
Peter Ove Christensen Joel S. Demski & Hans Frimor 《Journal of Accounting Research》2002,40(4):1071-1090
We emphasize the role of accounting policies, and their audit, in an earnings management setting. We use a two–period agency in which three frictions interact: the agent privately observes action (or effort) supply and output, and the initial contract is subject to renegotiation. This creates a setting in which both players' behavior is of concern, and, importantly, information rationing is efficient. Moreover, this information rationing is directly interpretable as being produced by an accounting policy whose application is ensured by an auditor. 相似文献
96.
97.
98.
S Judd 《Water science and technology》2005,51(6-7):27-34
The impact of fouling on the operation of submerged membrane bioreactors (MBRs) is discussed. The discussion proceeds through a review of the impacts of fouling and fouling speciation, with correlations of filterability against candidate foulants being provided. There follows a brief comparison of hydraulic performance of the submerged and sidestream configurations: data is presented to demonstrate the efficacy of coarse bubble aeration in the submerged MBR. The critical flux concept is then discussed and its applicability to MBRs deliberated in view of recent publications demonstrating fouling under sub-critical flux conditions. Finally, the two most commercially important MBR products are briefly reviewed with specific reference to design and operation for fouling amelioration. 相似文献
99.
Yu. A. Radin I. A. Grishin T. S. Kontorovich O. B. Panshina A. V. Chugin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(2):113-119
Problems arising with connecting the second exhaust-heat boiler to the first exhaust-heat boiler under load in the case of
flow circuits of combined-cycle plants of type PGU-450 are considered. Similar problems exist for two-boiler single-turbine
units of type PGU-325 and for two-boiler single-turbine units of traditional steampower plants with an output of 200–300 MW
upon connection of the second furnace of a two-furnace boiler to the operating first furnace. Analysis of the temperature-induced
stressed state and of the cyclic strength of thick-walled elements of the steam-water conduit of PGU-450 and of two-furnace
boilers of two-boiler single-turbine units with an output of 200–300 MW (the check valve, the inlet header of the water economizer)
is used for determining the steam temperature differences in the high-pressure conduits to the steam turbine and the order
of connection of the second exhaust-heat boiler to the operating fist one. Modes of enabling a two-boiler single-turbine unit
of a combined-cycle plant, which are most “rigid” from the standpoint of thermal strength, are determined.
__________
Translated from élektricheskie Stantsii, No. 2, February 2006, pp. 11–17. 相似文献
100.
The biological decolorization of two industrial, spent textile reactive dyebaths was investigated using a suspended-growth, halophilic mixed culture fed with glucose. Dyebath I contained mainly Reactive Blue 19 (RB19), an anthraquinone dye, whereas dyebath II contained mainly Reactive Blue 21 (RB21), a phthalocyanine dye. Batch assays under anaerobic conditions with the two neutralized dyebaths resulted in 87 and 37% extent of decolorization for dyebaths I and II, respectively. The rate of glucose utilization and the extent of acetate production were impacted in the presence of each dyebath as compared to the control culture. However, dyebath decolorization occurred despite moderate culture inhibition. Reuse of a biologically renovated RB19-containing dyebath in the dyeing process resulted in reproducible but not identical cotton fabric shades as compared to a standard dyeing (i.e., control) using fresh water. This difference is attributed to a variable degree of RB19 aggregation during the dyeing process and is not related to the efficiency of the biodecolorization process. Further improvement of the redyeing efficiency will lead to the development of an in-plant, closed-loop decolorization system resulting in significant water conservation and minimization of textile pollutants such as salt and dyes. 相似文献