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501.
 Polychlorinated biphenyls (PCBs), a type of persistent organic pollutants (POPs), are considered to be endocrine disrupters. According to the Stockholm Convention on POPs, PCB detoxification is being accelerated globally. We have developed an environmentally sound chemical PCB detoxification plant using the ultraviolet ray/catalyst method. The purpose of this paper is to check the design methodology for the PCB detoxification plant by the application of probabilistic safety analysis. First, possible hazardous events were determined; second, the weakest points in these hazardous events were established; and third, the impact when failures arise at the weak points in the system were studied. We clarified the preventive measures as follows. To prevent PCBs leaking into the environment, select leak-tight valves for the piping containing PCBs, and reduce the number of valves. To prevent fire or explosions due to leaks of an inflammable mixture, select leak-tight valves, reduce the number of valves installed in the piping, and improve the reliability of the suppression tank in the isopropyl alcohol (IPA) recovery unit. Received: February 27, 2001 / Accepted: June 17, 2002  相似文献   
502.
峡谷地形中森林地表火蔓延实验研究   总被引:1,自引:0,他引:1  
在峡谷形的受限结构实验台上进行森林火灾实验,燃料采用与林间可物相似的混合物,观测火蔓延过程在这种地型结构中的特点。改变风速,通过温度时间曲线分析林火蔓延过程以及烟气运动的规律,所得到的结果也将为林火模型进一步的建立提供实验依据。  相似文献   
503.
The traditional view of fire as a destructive agent requiring immediate suppression is giving way to the view that fire can and should be used to meet land management goals. Thus,fire control is being replaced by the more general concept offire management, which is based on the need to integrate fire policy with land management objectives. The social, economic, and ecologic effects of fire must be evaluated in the selection of land management alternatives.The activities of fire management organizations—fire prevention, control, and use of fire—must respond to needs of land management. Many agencies have developed fire organizations as separate entities that set their own objectives. The many land and resource managers who have recognized the need to incorporate fire considerations into land-use planning have so far lacked the techniques to do so.As a natural process, fire has an important function in forest and range ecosystems. Fire can greatly influence the quantity and quality of resource outputs; it is a two-edged sword that can either harm or benefit our goals, depending upon the complex effects of fire and the nature of our wants.The Fire in Multiple-Use Management Research, Development, and Applications (RD&A) Program was initiated by the U.S. Department of Agriculture, Forest Service, at the Northern Forest Fire Lab in Missoula to assist land managers. This profile explains what an RD&A program is; discusses its mission, goals, and approach to the problem; and tells why the approach involves federal laboratories, universities, and private research foundations.  相似文献   
504.
A Forest Planning Language and Simulator (FORPLAN) has been developed to facilitate the use of simulation for integrating fire into the land management planning process.FORPLAN incorporates unique characteristics of previous systems, links numerous models and data bases, allows selection of variable resolution levels, and permits discrete time simulation of disturbances on plants, fuels, and animals. No previous computer experience is required of the user, sinceFORPLAN recognizes simple English words and phrases.  相似文献   
505.
无粘结预应力混凝土框架的火灾试验   总被引:3,自引:1,他引:3  
首先对一榀单层单跨的无粘结预应力混凝土框架进行了常温下的加载破坏试验,然后通过模拟真实火灾环境,对四榀单层单跨的无粘结预应力混凝土框架进行了不同恒载、不同升温曲线、不同预应力度各工况的火灾试验,并进行了试验分析,从而为无粘结预应力混凝土框架的火灾反应分析提供了可靠的数据。  相似文献   
506.
火灾探测综合模拟实验平台   总被引:5,自引:4,他引:5  
针对火灾探测器性能检测准确性,方便性和可重复性的要求,立足国家探测器检测标准,研制了一个火灾探测综合模拟实验平台。该装置设计了开环和闭环两种可切换的工作方式。通过由模拟段与测试段组成的实验通风管道来模拟真实的火灾环境,并可施加一定的环境干扰信号,本平台还设计了集烟装置,从而可对火灾探测器的性能进行全面检测和评价。  相似文献   
507.
城市火灾扑救调度最佳路径分析   总被引:16,自引:0,他引:16  
针对城市火灾扑救中的资源调度问题,综合考虑道路交通的各种迟滞因素,对通用的Dijkstra法进行修正,通过对两种方法计算结果对比表明,修正算法更为合理。在此基础上,结合受灾建筑本身的情况和消防力量分布状况,运用地理信息系统、图论、网络拓扑分析等领域的理论和方法,建立了优化调度的模型,实现调度优化决策模块。  相似文献   
508.
CuZnAl形状记忆合金在井下火灾防预系统上的应用初探   总被引:3,自引:0,他引:3  
应用CuZnAl形状记忆合金的感温——驱动原理,制作井下火灾防预系统装置,具有较大的实用性。探讨该系统的设计原理及方法,研究复合细化、热处理工艺对形状记忆合金的影响  相似文献   
509.
采用机械燃烧方式和炉膛内部改造相结合方法以及装设省煤器和除尘器等技措施,对阜阳市青峰机械厂K4锅炉进行技术改造,不仅使排放烟尘达到国家标准,而且提高了锅炉热效率.经过几年运行实践,解决了K4锅炉烟尘污染问题,该方法对于保护环境,节约能源有较大的实用价值.  相似文献   
510.
Alate trapping studies of a monogyne population of the fire ant Solenopsis geminata indicate that two sizes of gynes are produced. Macrogynes, which participate in late spring and summer mating flights, are larger, fattier, and more than twice as heavy as microgynes, which participate in fall mating flights. Three patterns of gyne production were observed in 51 colonies studied: 35 produced macrogynes only, 9 produced microgynes only, and 7 produced both morphs, contributing to both summer and fall mating flights. Behavioral evidence and rearing studies suggest that macrogynes found new colonies independently, whereas microgynes achieve colony queen status by infiltrating or being adopted by established colonies. Of the total number of female alates collected from the trapped colonies, 56% were microgynes. However, because of their smaller size and lower fat content, microgynes made up only one-third of the caloric investment in female alates. By measuring the thorax lengths of queens from mature colonies, we determined that at least 56% were macrogynes and 35% or more were microgynes. These results indicate that as a reproductive strategy, colony investment in microgyne production may have at least as high a payoff as investment in macrogyne production.This is publication #24 of the Fire Ant Research Team  相似文献   
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