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51.
J. Karkheck  J.R. Powell 《Energy》1980,5(3):285-293
Given a vigorous development and implementation program, district heating could experience a high penetration of the space and water heating market in the United States and consequently yield very large reductions in fuel consumption. The spectrum of benefits affordable by district heating is discussed in detail and estimates of optimal service levels, energy conservation, and capital investment are described. To achieve such service levels requires the commitment of the federal government to form policies and furnish incentives that encourage application wherever the technology shows a favorable balance of benefits. A format is given for a national program to assess and implement district heating.  相似文献   
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The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of 40–60% and hydrogen production efficiencies by high temperature electrolysis of 50–70% are projected for fusion reactors using high temperature blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long-term, there could be a gradual transition to an inexhaustible energy system based solely on fusion.  相似文献   
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Conditioned 5 crows to key-peck for food reinforcement using standard operant-conditioning apparatus and procedures. Responding under fixed-ratio, variable-interval, variable-ratio, and fixed-interval schedules of reinforcement was successfully maintained for each S with substantial schedule requirements. Terminal patterns of response under each of the schedules were similar to those displayed by other species, with the exception that crows paused longer after reinforcement, and responded more slowly under fixed-interval schedules, than pigeons usually do. Functional relationships between measures of performance and schedule requirements were quite consistent with reports on other species. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Determination of the distribution of oxide charge and interface properties is important to an understanding of oxide charging phenomena such as that produced by irradiation. The physical mechanism dominating the voltage dependence of photoinjected currents in SiO2 is the scattering of electrons in the region of the oxide between the injecting electrode and the image force potential maximum. Since the spatial position of the potential maximum depends on the electric field resulting from space charge in the oxide as well as the field due to the applied voltage, analysis of the V-I characteristics of photoinjected currents can provide information about the spatial location of oxide charge. Presented in this paper are the results of an analysis of the effects of oxide space charge on the voltage dependence of photoinjected currents. It is shown that charge distribution in SiO2 can be nondestructively profiled over a range from about ten to several hundred angstroms from the injecting electrode. Since photoinjection V-I characteristics depend on electric field at the potential maximum in the oxide, whereas C-V characteristics depend on the field just inside the semiconductor, analysis of both characteristics permits distinction between charge in t e oxide a distance greater than about 10 ? and charge located at the interface.  相似文献   
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Inerdiffusion in two-phase Au-Co couples was investigated using metallographic and elec-tron microprobe analyses. Deviations from local equilibrium at the moving α-@#@ α interface were observed. These deviations were significant for short (1 to 2 h duration) anneals and, as the annealing time increased, the interface compositions approached the equilibrium val-ues. The interdiffusion coefficients (~D) and intrinsic diffusivities (DAu and DCo) in the α-Au terminal solid solution at 950° and 900°C were determined.  相似文献   
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