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51.
This paper outlines the implications of international approaches to humanitarian assistance in Afghanistan, focusing in particular on the period since the Taliban assumed power. It argues that international efforts to use conditionality on humanitarian assistance have proved ineffective in influencing the Taliban's policies, and have been implemented despite the negative impact on the welfare of the whole population. Efforts to adopt a principled approach to aid programming in this environment have also raised many ethical dilemmas which are likely to remain major challenges in that country and elsewhere.  相似文献   
52.
System safety is of particular importance for many industries. Broadly speaking, it refers to the state or objective of striving to sustainably ensure accident prevention through actions on multiple safety levers (technical, organizational, and regulatory). While complementary to risk analysis, it is distinct in one important way: risk analysis is anticipatory rationality examining the possibility of adverse events (or accident scenarios), and the tools of risk analysis support and in some cases quantify various aspects of this analysis effort. The end-objective of risk analysis is to help identify and prioritize risks, inform risk management, and support risk communication. These tools however do not provide design or operational guidelines and principles for eliminating or mitigating risks. Such considerations fall within the purview of system safety.In this work, we propose a set of five safety principles, which are domain-independent, technologically agnostic, and broadly applicable across industries. While there is a proliferation of detailed safety measures (tactics) in specific areas and industries, a synthesis of high-level safety principles or strategies that are independent of any particular instantiation, and from which specific safety measures can be derived or related to, has pedagogical value and fulfills an important role in safety training and education. Such synthesis effort also supports creativity and technical ingenuity in the workforce for deriving specific safety measures, and for implementing these principles and handling specific local or new risks. Our set of safety principles includes: (1) the fail-safe principle; (2) the safety margins principle; (3) the un-graduated response principle (under which we subsume the traditional “inherently safe design” principle); (4) the defense-in-depth principle; and (5) the observability-in-depth principle. We carefully examine each principle and provide examples that illustrate their use and implementation. We relate these principles to the notions of hazard level, accident sequence, and conditional probabilities of further hazard escalation or advancement of an accident sequence. These principles are a useful addition to the intellectual toolkit of engineers, decision-makers, and anyone interested in safety issues, and they provide helpful guidelines during system design and risk management efforts.  相似文献   
53.
This paper analyses the contribution of virtue ethics, the study of good character traits, to the humanitarian context. It argues that a virtue ethics perspective paints a realistic picture of the use of ethical standards in morally complex circumstances. Virtuous relief workers can employ standards in their thinking, but they are also committed to professional excellence that goes beyond any formal code. The concept of virtue ethics places a stress on moral development, which can be facilitated by role models that impart modest and feasible ideals. However, virtue ethics cannot provide simple guidelines on how to resolve difficult situations. It is possible that two virtuous persons can disagree on what should be done in a particular instance. In addition, a virtue ethics perspective emphasises the need for both individuals and organisations to discuss the actual purpose of relief work in order to pinpoint the virtues of a good relief professional.  相似文献   
54.
苯酚和酚类化合物是工业废水中的主要环境污染物,如焦化厂、炼油厂和石油化工厂等,去除工业废水中的酚类化合物对环境保护有极其重要的意义。通过富集驯化,从石化污水处理厂的活性污泥中筛选出一株产生物表面活性剂的高效苯酚降解菌。并对其进行了生理生化鉴定及降解性能的研究。实验结果表明,BPH-3菌为假单胞杆菌;菌株最佳的降解条件pH=7.0,温度为30℃,转速为150 r/min,最高耐盐度为3%,在接种量为5%,苯酚初始质量浓度为600 mg/L,菌株12 h内的降解率可达100%。  相似文献   
55.
生物降解是有机污染物去除的重要途径,为探究环境中微生物对2,4-二羟基二苯甲酮(2,4-dihydroxybenzophenone,BP-1)的降解能力,本文以BP-1为唯一碳源,设置好氧和厌氧条件分别驯化富集功能菌群,通过高通量测序技术深度解析群落多样性及功能菌群,在此基础上筛选关键功能菌,并评估其降解效能.结果显示...  相似文献   
56.
韩茜  王蓉蓉  史纯珍 《环境科学》2020,41(12):5617-5627
烹饪油烟的健康危害一直以来受到广泛关注.以甲醛为代表的醛类污染物是烹饪油烟排放的主要污染物之一.微生物法降解甲醛具有工艺简单、成本低及无污染等优点.本研究从烹饪油烟冷凝液中分离筛选出1株具有甲醛降解能力的菌株XF-1,经序列鉴定结合菌落形态特征及生理生化试验,该菌株被鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens sp.).该菌株具有能耐受高油环境的性能,最大耐受浓度为900 g·L-1.在甲醛浓度为100 mg·L-1的培养基中,菌株XF-1在34 h内的甲醛降解率为95.80%;当甲醛初始浓度<300 mg·L-1时,菌株XF-1能够在120 h以内完全降解溶液中的甲醛;甲醛浓度为800mg·L-1时,在96 h,菌株XF-1的降解率达到73.01%,并可耐受1.5 g·L-1浓度的甲醛.通过单因素(p H、接种量、甲醛浓度和温度)试验,得到该菌株最佳生长温度为30℃、最佳生长pH为6左右,最佳接种量为10%.利用GC-TOF-MS进一步分...  相似文献   
57.
七株有机磷农药降解菌的降解特性比较   总被引:18,自引:0,他引:18  
对分离自同一有机磷农药污染土壤的7株有机磷农药降解菌的降解特性进行了比较,7株降解菌都能利用甲基对硫磷为唯一碳源生长,并生成中间代谢产物对硝基苯酚.对硝基苯酚的降解经过一段延滞期,不同菌株降解对硝基苯酚的能力和延滞期有很大差异.降解菌株对多种有机磷类农药和芳香族化合物具有降解能力,其降解谱表现了一定的差异.用PCR方法从7株降解菌中克隆了有机磷农药水解酶基因.  相似文献   
58.
文章分析了变压吸附技术存在的问题,并提出解决措施。通过对变压吸附技术应用现状的总结,对该技术未来的发展方向进行预测与评价。指出变压吸附技术能够经济高效地实现物质的分离,有望成为分离技术未来的发展方向,为环保和工业生产做出更大贡献。  相似文献   
59.
The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) Everything is interconnected (and should usually stay that way), and (2) We can never do merely one thing. The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones.  相似文献   
60.
五氯酚(PCP)高效降解菌Psendomonas sp.CS5的研究   总被引:6,自引:0,他引:6  
从曾受五氯酚(pentachlorophenol,简称PCP,下同)污染废水的活性污泥中,经驯化富集和分离筛选获得一株PCP降解菌,菌号为CS-W-98-5.在24h内该菌降解w(PCP)=400×10  相似文献   
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