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41.
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
42.
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
43.
Ya. V. Maksimenko V. S. Nesterenko 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1989,23(11):617-620
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 6–7, November, 1989. 相似文献
44.
An innovative method for modelling biological processes under anaerobic conditions is presented and discussed. The method is based on titrimetric and off-gas measurements. Titrimetric data is recorded as the addition rate of hydroxyl ions or protons that is required to maintain pH in a bioreactor at a constant level. An off-gas analysis arrangement measures, among other things, the transfer rate of carbon dioxide. The integration of these signals results in a continuous signal which is solely related to the biological reactions. When coupled with a mathematical model of the biological reactions, the signal allows a detailed characterisation of these reactions, which would otherwise be difficult to achieve. Two applications of the method to the enhanced biological phosphorus removal processes are presented and discussed to demonstrate the principle and effectiveness of the method. 相似文献
45.
Steven N. S. Cheung 《Economic Affairs》1986,6(5):26-29
The speed with which communist China has embuaced markets has surprised Western analysis and observers, But Chinese economic progress will founder in corruption and inefficiency, argues Professor Steven Cheung of the university of Hong Kong, untess she insitutes a well-defined system of private property rights to safeguord investment and stimulate trade. 相似文献
46.
S K Smith 《Journal of economic and social measurement》1986,14(1):37-49
As the elderly population of the United States grows in absolute number and as a proportion of total population, accurate projections of that population become increasingly important for sound policy decisions. Cohort component techniques are typically used for state and local projections of the elderly population, but are often outdated or even nonexistent for many local areas. This paper suggests an alternative approach, based on Medicare data and simple projection techniques. Projections for several base periods and projection horizons are made for all states and for counties in Florida and are compared with actual Medicare enrollment. On the basis of these comparisons it appears that Medicare data and simple projection techniques can produce very useful short-run projections of the elderly population for states and local areas. 相似文献
47.
48.
Numerous labor-management issues possess ethical dimensions and pose ethical questions. In this article, the authors discuss four labor-management issues that present important contemporary problems: union organizing, labor-management negotiations, employee involvement programs, and union obligations of fair representation. In the authors view, labor and management too often view their ethical obligations as beginning and ending at the law's boundaries. Contemporary business realities suggest that cooperative and enlightened modes of interaction between labor and management seem appropriate.Robert S. Adler is Associate Professor of Legal Studies at the Kenan-Flagler Business School, University of North Carolina at Chapel Hill. He teaches courses in Business Law, Business Ethics, and Regulation. Prior to coming to UNC, Professor Adler served as Counsel to the Subcommittee on Health and the Environment of the Committee on Energy and Commerce of the U.S. House of Representatives.William J. Bigoness is Professor of Business Administration and Director, Center for Management Studies at the Kenan-Flagler Business School, University of North Carolina at Chapel Hill. His professional interests include organizational behavior, human resource management, and labor-management relations. Dr. Bigoness was Visiting Professor of Business Administration at the International Institute for Management Development (IMD) located in Lausanne, Switzerland from 1985 to 1987. 相似文献
49.
EDUARDO S. SCHWARTZ 《The Journal of Finance》1997,52(3):923-973
In this article we compare three models of the stochastic behavior of commodity prices that take into account mean reversion, in terms of their ability to price existing futures contracts, and their implication with respect to the valuation of other financial and real assets. The first model is a simple one-factor model in which the logarithm of the spot price of the commodity is assumed to follow a mean reverting process. The second model takes into account a second stochastic factor, the convenience yield of the commodity, which is assumed to follow a mean reverting process. Finally, the third model also includes stochastic interest rates. The Kalman filter methodology is used to estimate the parameters of the three models for two commercial commodities, copper and oil, and one precious metal, gold. The analysis reveals strong mean reversion in the commercial commodity prices. Using the estimated parameters, we analyze the implications of the models for the term structure of futures prices and volatilities beyond the observed contracts, and for hedging contracts for future delivery. Finally, we analyze the implications of the models for capital budgeting decisions. 相似文献
50.
Joel S. Sternberg 《期货市场杂志》1994,14(1):79-101