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101.
102.
A Gerber 《Canadian Metallurgical Quarterly》1976,157(1-2):42-53
In the Federal Republic of Germany there exist no statistical datas concerning death related to drug dependence until now. We propose to define death in connexion with drug dependence as the death of a drug dependent person caused by direct or indirect effect of the drug used. We first report on several international investigations; then the results of our own investigation in 40 cases of death in connexion with drug dependence in the district of Nordbaden are presented in detail. As a result it seems necessary to register drug dependent persons and to isolate those who are resistent to any therapy and thus represent a focus for further expansion of drug consuming. 相似文献
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Dietary lead (0.5%) was given to mice which, after mating, exhibited a vaginal plug. Estradiol, progesterone and prostaglandins E and F 2 alpha were determined in the plasma by radioimmuno assay at different times thereafter. The increase in estradiol and decrease in prostaglandins prior implantation are not greatly altered by lead treatment, whereas the subsequent increase in progesterone and later in estradiol is abolished. It is concluded that the lower number of pregnancies seen in lead-treated mothers is due to a maternal hormonal imbalance caused by lead. 相似文献
107.
Untersuchung des Stoffübergangs von festem Kohlenstoff in eine flüssige Eisen-Kohlenstoff-Schmelze für laminare Strömungsverhaltnisse bei konzentrischer Anordnung eines rotierenden Kohlezylinders in der Schmelze. Angabe einer Beziehung zur Ermittlung des Stoffübergangskoeffizienten. Einfluß von Temperatur und unterschiedlichem Kohlematerial. 相似文献
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VD Rodionov 《Canadian Metallurgical Quarterly》1980,66(1):119-124
The model consists of independent frequency-channels the amplitude-frequency characteristics (AFC) of which are assigned by the investigator. The phase characteristics are computed. Concrete minimum-phase model is described and illustrated. The temporal and frequency characteristics of this model are consistent with experimental data on peripheral auditory system. The AFC can be easily reformed, so the model is convenient for investigation of functional models of peripheral auditory analysis. 相似文献
110.
J.G. Usack L. Gerber Van Doren R. Posmanik J.W. Tester L.T. Angenent 《Journal of dairy science》2019,102(4):3630-3645
Anaerobic digestion coupled with combined heat and power production on dairy farms is environmentally advantageous; however, high capital and operating costs have limited its adoption, especially in the United States, where renewable electricity and heat production are under-incentivized. Biogas is also at a disadvantage because it has to compete with very low natural gas prices. The objective of this study was to evaluate the feasibility of integrating absorption refrigeration technology for combined cooling, heat, and power (CCHP) on the farm to help bridge this economic hurdle. A combined environmental life cycle and techno-economic assessment was used to compare 2 cooling pathways with and without co-digestion. We considered using CCHP to (1) displace electricity-driven refrigeration processes (e.g., milk chilling/refrigeration, biogas inlet cooling) or (2) mitigate heat stress in dairy cattle via conductive cow cooling. All cooling scenarios reduced environmental emissions compared with combined heat and power only, with an appreciable reduction in land use impacts when employing conductive cow cooling. However, none of the cooling scenarios achieved economically viability. When using cooling power to displace electricity-driven refrigeration processes, economic viability was constrained by low electricity prices and a lack of incentives in the United States. When used for conductive cow cooling, economic viability was constrained by (1) low waste heat-to-cooling conversion efficiency; (2) limited conductive cow cooling effectiveness (i.e., heat-stress mitigation); and (3) low heat stress frequency and limited severity. However, we predict that with minor improvements in conductive cow cooling effectiveness and in hotter climates, CCHP for conductive cow cooling would be economically viable even in current US energy markets. 相似文献