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991.
TNT当量法预测某石化设备爆炸后果评价   总被引:3,自引:0,他引:3  
以烃化反应器为模拟发生泄漏事故源,泄漏的物料形成爆炸性气体,发生爆炸事故,采用TNT当量法预测爆炸事故后果,通过公式,计算出因爆炸冲击波导致肺出血而引起死亡的概率为0.5的半径.  相似文献   
992.
In recent years, there has been increasing interest in positive organizational scholarship in general, including positive organizational behavior (POB) in particular. This work identifies organizational citizenship behavior (OCB) as a prototypical POB. Conceptualizing OCBs in this way is sensible in light of more than 30 years of research highlighting the desirable aspects of such behavior. At the same time, some researchers have raised questions about positive organizational scholarship and have called for a more balanced view of ostensibly positive behaviors. The purpose of this paper, then, is to take a more nuanced view of OCBs while highlighting the dark side of citizenship behavior. In doing so, we review conceptual and empirical work that has challenged the idea that OCBs are inherently positive. We also discuss research that seeks to develop a deeper understanding of the conditions under which OCB does more harm than good. Finally, important areas for future research and the practical realities facing scholars who seek to publish research investigating the dark side of citizenship are addressed as well. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
993.
The study aimed to find out the influence of sweating on footwear insulation with a thermal foot model. Simultaneously, the influence of applied weight (35 kg), sock, and steel toe cap were studied. Water to 3 sweat glands was supplied with a pump at the rate of 10 g/hr in total. Four models of boots with steel toe caps were tested. The same models were manufactured also without steel toe. Sweating reduced footwear insulation 19–25% (30–37% in toes). During static conditions, only a minimal amount of sweat evaporated from boots. Weight affected sole insulation: Reduction depended on compressibility of sole material. The influence of steel toe varied with insulation. The method of thermal foot model appears to be a practical tool for footwear evaluation.  相似文献   
994.
The article reflects on the changing world of work, and the challenges presented to both occupational health and occupational health education. We draw on the 63 preparatory workshops and the international conference in the “Work Life 2000: Quality in Work” program, an initiative of the Swedish Presidency of the European Union. The International Commission on Occupational Health is introduced, with particular concentration on a current practical project initiated by the Department of Health in South Africa, intended to lead to a set of projects, networking for occupational health education in developing countries. The practical initiatives cast light on a new set of issues that arise when occupational health and safety crosses cultural barriers, and previously separate comparative cases are linked.  相似文献   
995.
The study aimed at verifying a hypothesis that supporting a visual signal of regulation deviation with an auditory one could improve the quality of regulation; the operator would have better information on machine operation. A special simulator was applied to follow-up tracking with a manual lever which controlled vertical movements of a cursor on a monitor screen. Simultaneously with visual information on screen, the operator was provided with an auditory deviation signal of pre-determined characteristics. 33 young males underwent the test. It was found that supporting a visual signal with an auditory one resulted in an improvement in the regulation quality by 5-6%, which proved synergy between those signals. The results may be used in designing tele- and servo-mechanisms, especially for remote control machinery, e.g., inspection robots or micromanipulators controlled by operators in a follow-up system.  相似文献   
996.
Abstract

Aim. The aim of this study was to evaluate working conditions with a notebook computer (notebook) as a potential cause of musculoskeletal disorders. Material and methods. The study had 2 stages. The first one was a questionnaire survey among 300 notebook users. The next stage was an expert analysis of 53 randomly selected workstations. The questionnaire survey included questions about the participants, their working conditions, work organization and also duration of work with a notebook. Results and conclusions. The results of the research showed that most examined operators used a notebook as a basic working tool. The most important irregularities included an unadjustable working surface, unadjustable height of the seat pan and backrest, unadjustable height and distance between the armrests and no additional ergonomic devices (external keyboard, docking station, notebook stand or footstool).  相似文献   
997.
海州矿高矿化度矿井水脱盐试验研究   总被引:1,自引:0,他引:1  
海州矿矿井水一直都以排放为主要处理方式,不仅污染了水资源,还造成水资源的浪费.水质分析表明,海州矿矿井水属高矿化度矿井水.针对矿井水含盐量高、硬度大的特点,对此类高矿化度矿井水的脱盐方法和脱盐率的影响因素进行了理论分析和试验研究.经过运行费用和运行可靠性等方面的分析比较,确定选用电渗析方法脱盐.试验选用了一定规格的电渗析器,在试验中通过改变电渗析器的工作条件,绘制曲线来分析主要工艺参数的变化对脱盐效率的影响.试验结果表明,在工作电压为55 V、工作电流为1.86 A时,脱盐率达到70%以上.  相似文献   
998.
北京市相对资源承载力分析   总被引:17,自引:1,他引:17  
相对资源承载力是区别于传统资源承载力的一种计算区域资源承载力的方法.本文采用该方法,分别以全国和国内同等城市--上海作为参照区对北京市相对资源承载力进行了分析.研究表明,近年来北京市相对资源承载力处于超载状态,且有逐渐加剧的趋势.而造成这种状况的根本原因是产业结构不合理导致的资源消耗型的经济发展模式.调整产业结构,转变经济增长模式,从而提升北京市相对资源承载力,对北京实现人口-资源-环境的可持续发展具有重大意义.  相似文献   
999.
利用木薯渣进行纤维素分解菌混合发酵工艺研究   总被引:8,自引:0,他引:8  
从自然界中筛选出6株相互间无拮抗作用的纤维素分解菌进行混合发酵,研究了该混菌以工业废弃物木薯渣为原料发酵的最佳产酶条件是:培养基配方为木薯渣4 g,黄豆粉0.75 g,KH2PO40.20 g,NaCl 0.02g,MgSO4·7H2O 0.015 g,蒸馏水1 000 mL;发酵工艺为初始pH=7.0,培养温度40℃,每250 mL锥形瓶装培养液140mL,接种量3%,在140 r·min-1转速下发酵72 h.结果表明,混合菌的发酵可大幅度提高纤维素酶活力及对还原糖的耐受力.  相似文献   
1000.
应用各种爆炸后果估计模型对液化气运输过程中的爆炸后果进行了评估,并用ETA分析方法对存在的危险进行了分析,指出了控制措施。  相似文献   
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