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ABSTRACT: This article models the production choice decision of local governments for the delivery of services to citizens. fie production choice decision depends on the demand by the local government for contracting out and the supply of external producers. Local governments trade off the potential cost savings of external production against diminished control of the service delivery process. Fiscal, political, and structural constraints affect the willingness of a local government to consider this tradeoff The model is estimated for eight local government services using data from a national sample of local governments. The services represent a cross-section of those provided by local governments, including public works, recreational, and social services. The results indicate the general importance of fiscal forces, resistance by public employees, and cost savings that result from competitive supply markets on the production choice decision. 相似文献
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The density, transformation-range behavior, and electrical conductivity of three glass-crystal systems of increasing complexity were measured. The systems studied included glass/alumina composites, spherulitic lithium disilicate crystallized from glass of the same composition, and a commercial glass-ceramic in which the crystallization of lithium metasilicate resulted in changes in the composition of the residual glass. 相似文献
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LESLIE N. KAHN ZEKI BERK ERNST R. PARISER SAMUEL A. GOLDBLITH JAMES M. FLINK 《Journal of food science》1974,39(3):592-595
Loigo species of squid was investigated as a potential source of protein isolate. The various process parameters which influence extraction of protein (particle size, time, extraction pH, salt concentration, relative amount of solvent to squid tissue and temperature) were investigated. From this study the following parameters were chosen to optimize extraction: pH 11 (sodium hydroxide) or 4% salt concentration (sodium chloride, sodium hexametaphosphate in aqueous extractant); temperature = 22°C; time = 45 min; particle diameter = 2–3 mm; solvent-to-squid ratio = 10:1. Under these conditions, about 85% of the squid protein can be extracted. 65% of the extracted nitrogen is recovered as protein isolate by isoelectric precipitation at pH 5. 相似文献
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JAMES J. GANGLER 《Journal of the American Ceramic Society》1954,37(7):312-316
In conjunction with studies of the suitability of liquid metals for high-temperature heat-transfer systems, an investigation was made to determine the resistance of forty materials–eighteen ceramics and cermets, thirteen refractory metals, and nine high-temperature alloys–to attack by Pb-Bi eutectic alloy (44.5% Pb and 55.5% Bi) in a dynamic system at temperatures of 1500° or 2000°F. The experimental apparatus and procedure is described. With the exception of ZrC all the ceramics and cermets were resistant to attack by molten Pb-Bi eutectic at 2000°F. Of the thirteen refractory metals only arc-cast molybdenum exhibited resistance to Pb-Bi at 2000°F. All nine of the high-temperature alloys had poor resistance at 1500°F. 相似文献