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741.
为了研究化工园区内发生地震灾害后的事故演化过程,利用事故链模型对地震次生灾害演化过程进行分析,并将其转化为贝叶斯网络,确定各节点的变量与状态取值范围;通过相关文献及专家经验判断分析,获得贝叶斯网络中各节点的条件概率;依据贝叶斯网络的推理策略,比较不同地震烈度下,各化工事故发生的后验概率值,并探讨应急救援的及时性对地震次生灾害发生概率的影响,从关键要素遏制化工事故的发生,采取针对性的应对措施,尽可能的降低化工事故,有效的降低人员伤亡及财产损失。 相似文献
742.
建立了食品工业废水中8种合成色素残留的固相萃取-液相色谱测定方法.水样经固相萃取柱富集,氮吹浓缩定容后直接进样.采用C18色谱柱分离,以甲醇-乙酸铵(0.01mol·L-1)溶液为流动相,进行梯度洗脱,最后利用二极管阵列检测器(DAD)进行可变波长分析,外标法定量.结果表明,8种合成色素在1.0—50mg·L-1的浓度范围内线性良好,相关系数均大于0.999,定量限为1.6—2.4μg·L-1.以实际废水样品为加标对象,分别考察了低、中、高三个浓度水平的加标回收率和精密度,平均加标回收率在82.3%—95.9%之间,精密度均小于5.45%.该方法准确可靠,灵敏度高,可用于食品工业废水中痕量色素残留的测定. 相似文献
743.
悬挂链曝气工艺应用于中小城镇污水治理 总被引:3,自引:0,他引:3
王涛 《城市环境与城市生态》2004,17(1):28-30
通过对悬挂链曝气工艺特点和应用情况的分析,总结了针对中小城镇污水处理厂的设计与建设经验。结合我国国情,提出悬挂链曝气工艺为中小城镇污水处理厂的建设提供了一个良好的选择。 相似文献
744.
本文从灾害链的角度闸述了该区的灾害类型及活动模式。在系统分析灾害对社会经济的影响后,得出因灾造成的损失,其比重是很大的。本区灾害具有强度大、突发性强、分布广、区域性强,以及同步迭加交替出现和周期性特点。在此基础上对灾害发展趋势作了预测,提出了相应的防治对策。 相似文献
745.
746.
Philip White 《Disasters》2005,29(S1):S92-S113
This paper examines the 1998–2000 'border' war between Eritrea and Ethiopia and its continuing legacies from the perspective of food security.1 Focusing on the food crisis that hit both countries during the same period and was allowed to develop into a famine in southeast Ethiopia, it argues that this was linked with the war in more ways than hitherto recognised. Such connections can be appreciated only by taking a longer-term view of the decline of the rural economy of which this food crisis was part, factoring in the role played by this and other conflicts that have flared up in the region. An analysis of this kind might have helped donors and aid agencies to respond more effectively both to short-term humanitarian needs in the midst of an inter-state war and to the need for longer-term support for food security in a region beset by endemic conflict. 相似文献
747.
James R. Clark Donald S. Cherry John Cairns 《Journal of the American Water Resources Association》1982,18(5):761-761
ABSTRACT: Protein, carbohydrate, and organic content of Aufwuchs samples from artificial streams dosed separately With chlorine, copper, or dextrose were altered by changes in the taxonomic composition or physiological condition of the community. Protein content increased as community composition shifted toward a dominance. by blue-green algae or heterotrophs. Bluegreens or cyanobacteria were dominant most often in Aufwuchs developing under copper or chlorine treatments and when water temperatures approached the seasonal maximum (22.8 C-25.8 0, while heterotrophs proliferated in the dextrose-enriched stream. Due to the associated extracellular mucilage, carbohydrate content also tended to be higher when blue-green algae or bacteria were abundant. However, carbohydrate content decreased in communities developing under chlorine or copper treatments at low or moderate temperatures (3 C-22.8 C), indicating a utilization of stored photosynthetic products to adapt to the stress. The organic content of Aufwuchs was related to the extent of mucilage production and the tendency of the community to accumulate detritus and suspended inorganic sediment. Protein and carbohydrate estimates were significantly correlated with dry weight and ash-free dry weight, a result of the copious extracellular mucilage associated with rapidly growing blue greens and other bacteria. Estimates of Aufwuchs food quality are important in evaluating the impact of pollutants on higher trophic levels; however, the tendency of change with both taxonomic shifts and physiological adaptations tends to confound interpretations for water quality assessment. 相似文献
748.
ABSTRACT Firstly, on the basis of literature research, sort out and summarize the critical coupling relationship among the upstream, middle, and downstream enterprises in the wind power industry chain. Secondly, the evaluation index system of coupling coordination degree of China’s wind power industry chain was established. Based on entropy weight method and subsystem efficiency function, the capacity coupling (CC) coefficient model of wind power industry chain subsystem was established. The coupling coordination degree between the upstream subsystem and the midstream subsystem of the wind power industry chain, and between the midstream subsystem and the downstream subsystem is dynamically evaluated, and the coupling coordination degree evaluation model of the wind power industry chain in China is proposed. Thirdly, according to the relevant statistical data of China from 2010 to 2017, this paper conducts an empirical study on the coupling of the upstream, middle and downstream subsystems of the wind power industry chain. Finally, based on the collaborative coupling study of China’s wind power industry chain, this paper analyzes the key factors influencing the collaborative development of wind power industry chain, and puts forward Suggestions on the optimization of the collaborative development of China’s wind power industry chain. 相似文献
749.
Anne C. Bellows 《Journal of Agricultural and Environmental Ethics》2003,16(3):249-279
Exposing food violences – hunger,malnutrition, and poisoning from environmentalmismanagement – requires policy action thatconfronts the structured invisibility of theseviolences. Along with the hidden deprivation offood is the physical and political isolation ofcritical knowledge on food violences and needs,and for policy strategies to address them. Iargue that efforts dedicated on behalf of ahuman right to food can benefit from thetheoretical analysis and activist work of theinternational Women's Rights are Human Rights(WRHR) movement. WRHR focuses on women andgirls; the food rights movement operates onbehalf of all people, with an emphasis on thepoor. Both attend to the protection of bodilyintegrity against physical and psychicviolences. Both cope with bodily violences thatare socially privatized and spatiallysegregated from public institutions of relief,that is, they are tacitly omitted from publicdiscourse and purview. Most typically, but notexclusively, these violences unfold in privatehousehold space. Both rights movements mustmobilize political rights to demand economicand social rights and security. I introduce theUnited Nations' early Declaration (1948) andCovenant (1966) language on the human right tofood and review problems of household accessand grassroots engagement that are ``writteninto' this early documentation. An abbreviatedoverview of the WRHR movement describes how thepublic/private and economic/political rightsdichotomies have been critiqued andre-formulated. A case study set in Polandacross the transition from (more) communist to(more) capitalist political economies attemptsto illuminate the discussion through agrounded example. 相似文献
750.
中国未来粮食问题的忧患--以石油、煤为原料的化石农业将终结 总被引:2,自引:1,他引:2
现代农业的成就是建立在石油化学工业上的,所以被称之为“石油农业”。但是随着石油资源的枯竭,石油农业也将终结。作者讨论了这个危机,研究了替代石油的煤及相关的农业问题。结论是石油和煤的枯竭及开采困难;21世纪中晚期中国的粮食问题将面临严重困难。 相似文献