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961.
Information relating to piping damage in safety-relevant systems in German nuclear power plants with light water reactors (both pressurized water reactors (PWRs) and boiling water reactors (BWRs)) were analyzed with respect to the modes and the causes of damages. In general, the total range of observed piping damage is low. The incidents (82) in plants with PWRs affected mainly pipes with small diameters. Almost all damaged piping showed wall-penetrating cracks combined with leakages, which revealed the damage. Initial cracks at piping with larger diameters were discovered in isolated cases during in-service inspections. With regard to the incidents (71) in plants with BWRs, piping with small as well as large diameters was affected to different degrees. Wall-penetrating cracks combined with leakages were detected at piping with small diameters. For large-diameters pipes, cracks were indicated during in-service inspections and supplementary examinations. The results of the incident evaluations confirm the conservativeness of the safety concept chosen for the design of German nuclear power plants with light water reactors. 相似文献
962.
Klaus Niemel 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,48(1):17-28
Treatment of cotton cellulose with 3 M sodium hydroxide solution at 260°C and 280°C gave a mixture of carboxylic acids with a yield of > 95%. The identified 50 carboxylic acids included both hydroxy monocarboxylic acids and dicarboxylic acids; their routes of formation are discussed. Among the main compounds were lactic, glycolic, 2-hydroxy-2-methylpropanoic, 2-hydroxybutanoic, 3,4-dideoxypentonic, anhydroisosaccharinic, 2,3-dideoxypentaric, and 3,4-dideoxyhexaric acids. Technical utilisation of this kind of acid mixture requires further studies. Investigations of the cyclic compounds, formed in small amounts only, resulted in identification of mainly alkyl-substituted 2-cyclopenten-1-ones. 相似文献
963.
964.
965.
Reports an error in the original article by K. R. Scherer and H. G. Wallbott (Journal of Personality and Social Psychology, 1994[Feb], Vol 66[2], 310–328). On page 325, the 2nd and 3rd terms in the leftmost column of figure 2 should be interchanged. (The following abstract of this article originally appeared in record 1994-29654-001.) Reviews the major controversy concerning psychobiological universality of differential emotion patterning vs cultural relativity of emotional experience. Data from a series of cross-cultural questionnaire studies in 37 countries on 5 continents are reported and used to evaluate the respective claims of the proponents in the debate. Results show highly significant main effects and strong effect sizes for the response differences across 7 major emotions (joy, fear, anger, sadness, disgust, shame, and guilt). Profiles of cross-culturally stable differences among the emotions with respect to subjective feeling, physiological symptoms, and expressive behavior are also reported. The empirical evidence is interpreted as supporting theories that postulate both a high degree of universality of differential emotion patterning and important cultural differences in emotion elicitation, regulation, symbolic representation, and social sharing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
966.
967.
Thanks to their high specific energy content, their cost-favourable materials, and their good environmental compatibility, zinc/atmospheric oxygen batteries are of interest as energy source for electrotraction. Rechargeable zinc/atmospheric oxygen batteries are particularly suitable for this application. Use of atmospheric oxygen as reactant requires a semi-open construction with stringent demands on the materials of the interface. The state of the art of variants of this battery type and the principal components (air-diffusion electrode, zinc electrode, electrolyte) are presented in detail and discussed in this review article. 相似文献
968.
969.
970.
Klaus Strohmeier 《化学,工程师,技术》1993,65(4):410-414
Estimation of Potential Danger Arisig from Pressure-Condensed Gases. Analytical solutions are shown for a specific industrial application in order to estimate the potential danger of pressure condensation of gases. First of all it should be determined in which positions high stresses have to be expected. Afte excluding the case “Bruch vor Leck” (breakage before leak), possible cross sections of leakages can be stated. The laws of thermodynamics laws can be used to determine quantities pertaining to the states of aggregation concerned (liquid/gaseous) may be determined in case of failure. Finally it is possible to determine the size of the ground cradle as well as possible undergrate firing by an investigation of the processes at the liquied pools. Finally we indicated a water sprinkling plant sufficient for handling cases of fire. It was taken into account that the total heat of combustion of the leakage stream will be transferred to the cooling water film. 相似文献