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351.
囊式蓄能器是液压系统中常用的压力容器。在更换胶囊和(或)充装氮气时如操作不当,有发生爆炸的风险。通过对一起蓄能器爆炸事故的调查,经计算、推论,得出此次爆炸是一起物理爆炸。并就事故发生原因及其爆炸强度、危害程度进行了分析。提出生产商和使用单位应制定科学的、可行的标准操作程序(Standard Operation Program,SOP),并要求工人在实际操做中严格执行,加强过程控制,避免事故的发生。  相似文献   
352.
清罐危险性分析及防范措施   总被引:1,自引:0,他引:1  
介绍了油罐清罐的类型,论述了油罐清罐的常见风险,并对其进行了分析,同时提出了相应的防范措施.  相似文献   
353.
地质环境的恶化,造成各类地灾害不断发生,直接威胁着人民生命财产的安全,越来越受到党和政府高度重视。本文通过10年来地质灾害治理施工,并根据滑坡施工的控制因素及特点,摸索了一套行之有效的安全管理办法和措施,有效地遏制了地质灾害施工安全事故,收到比较明显的效果。  相似文献   
354.
从晶相组成、晶格缺陷密度、表面羟基含量、晶粒尺寸以及比表面积等方面阐述了热处理温度与TiO2光催化剂结构性质的关系,并就混晶效应、载流子输运/俘获以及尺寸量子效应等对光催化活性的影响进行了讨论。此外,还汇总了对水中典型有机污染物的光催化氧化研究以及相关的催化剂结构性质。  相似文献   
355.
垃圾堆酵对焚烧厂垃圾热值的影响   总被引:6,自引:0,他引:6  
分析了垃圾焚烧厂的渗滤液;基于渗滤液的体积和CODcr值,估算焚烧厂垃圾堆酵对垃圾热影响以及焚烧厂垃圾的适宜堆酵时间,实验结果表明,上海生活垃圾渗滤液是生化性好的高浓度有机废液,堆酵5d,其低位热值〉4600KJ/kg,可直接焚烧。  相似文献   
356.
Thermal modeling techniques constrained by published petrological and thermo-chronometric data were applied to examine late orogenic burial and exhumation at a Variscan suture zone in Central Europe. The suture separates the southern Rhenohercynian zone from the Mid-German Crystalline Rise and traces the former site of a small oceanic basin. Closure of this basin during Variscan subduction and subsequent collision of continental units were responsible for different tectono-metamorphic evolutions in the suture's footwall and hanging wall. Relative convergence rates between the southern Rhenohercynian zone and western Mid-German Crystalline Rise can be inferred from the pressure-temperature-time evolution of the Northern Phyllite Zone. During Late Viséan-Early Namurian times, horizontal thrusting velocities were at least 20 mm/a. Thermal modeling suggests that exhumation of the Mid-German Crystalline Rise occurred temporarily at rates of more than 3 mm/a. Such rapid exhumation cannot be produced by erosion only, but requires a substantial contribution of extensional strain. Exhumation by upper crustal extension occurred contemporaneously with convergence and is explained by continuous underplating of crustal slices and thrusting along faults with ramp-flat geometry. Finally, implications for the tectono-metamorphic history of the study area and the thermal state of the crust during late Variscan exhumation are discussed.  相似文献   
357.
环境中有毒、易燃、易爆等物质的泄漏将会在不同程度上对人体和周围环境造成伤害。为此建设项目(特别是化工行业)在进行环境影响评价时,必需对这些潜在的危害物质及其可能发生的事故进行危害分析。本文通过对天津中河化工厂罐区扩建工程的危害分析,给出了危害分析的基本过程及其分析的理论方法,以便为今后化工行业建设项目的危害分析提供一个理论参考。  相似文献   
358.
I develop a state-based dynamic model of behavior to demonstrate that size-dependent differences in temperature tolerances are not necessary to account for the activity of small male digger wasps late in the day. In the model, males defend or patrol the nesting area, wait near nests, or feed away from the nesting area depending on time of day, energy reserves and size rank. I assume a large male competitive advantage, so mating opportunities decrease with size rank for territorial or patrolling males and are rare for all waiting males; the costs of patrolling or defense are higher than the costs of waiting. If energy reserves of all males are initially small, all males alternate feeding and territorial or patrolling behavior. If energy reserves are initially large, large males patrol or maintain territories until they risk starvation and leave the area to feed. At this time, smaller males that have conserved their resources by waiting and feeding may defend territories or patrol. I simulate the behavior of three populations representing two species of Microbembex by assuming large initial energy reserves for populations in which males were territorial and small initial reserves for populations in which males patrolled, and then convert the predicted time of activity to temperature using local regressions from field studies. Temporal patterns in the activity of large and small males were similar to those actually observed, and relationships between size and temperature predicted by the model corresponded to most observations and were sometimes positive. Thus, the delayed activity of smaller males does not correspond to activity at higher temperatures and is probably not attributable to size-dependent thermal tolerances, but may represent a temporal displacement of mating activity due to intra-sexual competition and mediated by energetics. The model makes testable predictions on the timing of feeding and depletion of energy reserves in relation to size and initial energy state, and suggests how differences among species may influence the temporal and spatial organization of male mating behavior. Received: 27 February 1997 / Accepted after revision: 26 July 1997  相似文献   
359.
Human risk assessment of As,Cd, Cu and Zn in the abandoned metal mine site   总被引:2,自引:0,他引:2  
The cancer risk and the non-cancer hazard index for inhabitants exposed to As, Cd, Cu and Zn in the soils and stream waters of the abandoned Songcheon Au–Ag mine area were evaluated. Mean concentrations of As, Cd, Cu, Pb and Zn in agricultural soils were 230, 2.5, 120, 160, and 164 mg kg−1, respectively. Mean concentrations of As, Cd and Zn of the water in the stream where drinking water was drawn was 246 μg L−1, 161 μg L−1 and 3899 μg L−1, respectively. These levels are significantly higher than the permissible levels for drinking water quality recommended by Korea and WHO. The resulting human health risks to farmers who inhabited the surrounding areas due to drinking water were summarized as follows: (1) the non-cancer health hazard indices showed that the toxic risk due to As and Cd in drinking water were 10 and 4 times, respectively, greater than those induced by the safe average daily dosages of the respective chemicals. (2) the cancer risk of As for exposed individuals through the drinking water pathway was 5 in 1000, exceeded the acceptable risk of 1 in 10,000 set for regulatory purposes.  相似文献   
360.
矿区开采沉陷地质灾害与防治对策研究   总被引:4,自引:0,他引:4  
刘梅  曾勇 《环境科技》2005,18(3):29-32
分析了开采沉陷地质灾害的成因,着重研究了开采沉陷地质灾害的危害状况,最后提出了应积极进行开采沉陷监测预报、综合采用减轻地表沉降技术、全面治理塌陷区域环境灾害等综合防治对策。  相似文献   
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