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941.
If produced and arranged in the right way with carbon dioxide as a possible but permanently removed by-product, hydrogen as a new, large scale, applicable energy carrier promises significant reductions of carbon dioxide emissions. It is light, non-toxic, and clean burning. In different parts of the world, viz. United States, Japan, and Europe, programs have started some years ago to investigate hazardous properties of hydrogen in more detail and to develop special safety measures where necessary. Recently, in September 2009, the third International Conference on Hydrogen Safety (3rd ICHS) was held at Corsica, France. CFD tools have been adapted to describe hydrogen dispersion and explosion. Field tests have been carried out, an incident databank has been founded, knowledge gaps were defined, and risk analysis methods reviewed. The latter are required for drafting installation guidelines and measures for safe distances in land-use planning and licensing of hydrogen storage locations, pipelines, and re-fuelling stations. Yet some challenges remain. The paper will summarize present results and will address hydrogen related issues where more knowledge is needed to reduce uncertainty and improve the quality of risk control.  相似文献   
942.
The effect of carbon dioxide (CO2) concentration on the ignition behaviour of hydrocarbon and CO2 gas mixtures is examined in both jets and confined explosions. Results from explosion tests are presented using a 20 l explosion sphere and an 8 m long section of 1.04 m diameter pipeline. Experiments to assess the flame stability and ignition probability in free-jets are reported for a range of different release velocities. An empirically-based flammability factor model for free-jets is also presented and results are compared to ignition probability measurements previously reported in the literature and those resulting from the present tests.The results help to understand how CO2 changes the severity of fires and explosions resulting from hydrocarbon releases. They also demonstrate that it is possible to ignite gas mixtures when the mean concentration is outside the flammable range. This information may be useful for risk assessments of offshore platforms involved in carbon sequestration or enhanced oil recovery, or in assessing the hazards posed by poorly-inerted hydrocarbon processing plant.  相似文献   
943.
为了探讨灭活面包酵母菌对Pb2+、Cd2+的单、双重金属离子体系(以下简称双离子体系)的吸附效果及影响机制,选择灭活面包酵母菌为吸附剂,对Pb2+、Cd2+的单离子体系和Pb2+-Cd2+双离子体系吸附动力学过程和等温吸附效果进行研究.结果表明,不同离子体系中,在相同初始浓度情况下,面包酵母菌对Pb2+的吸附量总是大于对Cd2+的吸附量.试验条件下,面包酵母菌对Pb2+、Cd2+的单离子体系和Pb2+-Cd2+双离子体系等温吸附符合Langmuir模型,最大吸附量qmax分别为0.414 9 mmol/g、0.346 8 mmol/g和0.488 5 mmol/g.SEM/EDS分析表明,Pb2+、Cd2+被吸附到菌体上,造成菌体变形或出现破裂,并使内部物质外泄,这可能是吸附进行一定时间后出现二次吸附过程的主要原因.灭活面包酵母对Pb2+和Cd2+具有良好的吸附效果,对Pb2+-Cd2+双离子体系的吸附,离子间的点位竞争和联合毒性作用是影响体系总体吸附效果的重要因素.  相似文献   
944.
The current study adds to a growing body of research on dark personality traits by investigating the moderating role of promotion focus on the relationships among dark triad traits and facets of job performance. Specifically, we investigated the effects of the dark triad (i.e., Machiavellianism, narcissism, and psychopathy) on supervisor ratings of performance, and the moderating effect promotion focus has on those effects. Using field data, we surveyed 549 employees from a manufacturing company in the USA and obtained supervisor ratings of task performance and helping behavior for each employee. We found support for multiple hypotheses, which suggests that managers rated narcissistic and psychopathic employees as having poorer task performance and psychopathic employees as engaging in fewer helping behaviors than employees low in those traits. Furthermore, promotion focus strengthened these negative relationships. We did not find these effects for Machiavellianism. Implications of these findings for future dark personality research as well as the practical implications for managers and organizations are discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
945.
Idiosyncratic deals (i‐deals) research focuses on the emergence of customized work arrangements employees negotiate with their employers. This article provides a critical review and synthesis of i‐deals research, combining a qualitative review of i‐deals theory and research with a supplementary meta‐analysis of 23 empirical studies (k = 27 samples, N = 8110 individuals). The qualitative review examines the conceptualization and measurement of i‐deals and identifies patterns and gaps in i‐deals research, while the quantitative meta‐analysis tests the moderating effect of societal cultures on the predictors and consequences of ideals investigated to date. In each section, attention is given to strengths and weaknesses of current approaches to i‐deals theory and research. Future research directions are identified with particular emphasis on the largely unexamined role of i‐deals from a multilevel perspective. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
946.
This study among a sample of 207 general practitioners (GPs) uses a five‐year longitudinal design to test a process model of burnout. On the basis of social exchange and equity theory, it is hypothesized and found that demanding patient contacts produce a lack of reciprocity in the GP–patient relationship, which, in turn, depletes GPs' emotional resources and initiates the burnout syndrome. More specifically, structural equation analyses confirmed that—both at T1 and T2—lack of reciprocity mediates the impact of patient demands on emotional exhaustion. Emotional exhaustion, in turn, evokes negative attitudes toward patients (depersonalization), and toward oneself in relation to the job (reduced personal accomplishment). Moreover, this process model of burnout was confirmed at T2, even after controlling for T1‐scores on each of the model components. Finally, T1 depersonalization predicted the intensity and frequency of T2 patient demands, after controlling for T1 patient demands. This major finding suggests that GPs who attempt to gain emotional distance from their patients as a way of coping with their exhaustion, evoke demanding and threatening patient behaviors themselves. The theoretical and practical implications of these findings are discussed. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
947.
A laboratory experiment was conducted to test relationships between leadership style, feedback on subordinate performance within the context of either the vision or goals of the organization, and leader cognitions representing a modified version of Wofford and Goodwin's (1994) cognitive processing model of leadership. The results indicated that: (1) positive feedback leads to the access of transformational cognitions, whereas negative feedback leads to the access of transactional cognitions; (2) negative feedback about subordinate performance causes transformational leaders to access transactional cognitions in response to subordinates; (3) the relationship between transformational leadership behavior and transformational cognitions is strengthened when feedback received about subordinates is vision‐related compared to feedback that is goal‐related; and (4) the relationship between transactional leadership behavior and transactional cognitions is strengthened when feedback received is goal‐related compared to feedback that is vision‐related. Limitations and future research directions are discussed. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
948.
The paper deals with training and research using maritime simulation techniques to provide cost-effective and safe solutions to maritime transportation problems. In order to reduce the probability of accidents, training and research is required in which the human factors are fully taken into account.  相似文献   
949.
Two experimental studies were conducted to examine whether the stress‐buffering effects of behavioral control on work task responses varied as a function of procedural information. Study 1 manipulated low and high levels of task demands, behavioral control, and procedural information for 128 introductory psychology students completing an in‐basket activity. ANOVA procedures revealed a significant three‐way interaction among these variables in the prediction of subjective task performance and task satisfaction. It was found that procedural information buffered the negative effects of task demands on ratings of performance and satisfaction only under conditions of low behavioral control. This pattern of results suggests that procedural information may have a compensatory effect when the work environment is characterized by a combination of high task demands and low behavioral control. Study 2 (N=256) utilized simple and complex versions of the in‐basket activity to examine the extent to which the interactive relationship among task demands, behavioral control, and procedural information varied as a function of task complexity. There was further support for the stress‐buffering role of procedural information on work task responses under conditions of low behavioral control. This effect was, however, only present when the in‐basket activity was characterized by high task complexity, suggesting that the interactive relationship among these variables may depend on the type of tasks performed at work. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
950.
Bhopal Gas Tragedy was the worst industrial accident in the world where several thousand persons lost their lives. It occurred at the Union Carbide plant located inside the city of Bhopal and close to the railway station, at midnight of December 2-3, 1984 due to the leakage of MIC gas which took the local sleeping and floating population unawares.

This paper describes the experience of a transit passenger who reached the Bhopal Railway Station by train at about the same time when the deadly gas leakage occurred.  相似文献   

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