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741.
针对采油管柱落井事故原因多且复杂的问题,基于FT与BCCT对采油管柱落井事故进行溯源分析。通过建立采油管柱落井事故树(FT)计算最小割集,绘制等效事故树;结合博德事故因果连锁理论(BCCT)确定直接原因、间接原因,在此基础上追溯其根本原因。结果表明:造成采油管柱落井事故的直接原因是油管挂断裂、油管断裂、修井队操作失误、卡瓦故障;间接原因是油管挂或新油管或丝扣或卡瓦质量差、油管挂或油管长期服役、修井频繁、操作不稳、解卡不当、起下钻操作不当、对扣作业不当、设备失灵、卡瓦磨损严重、卡瓦操作失误;根本原因是与管理相关的产品采购、校准、检验、试验过程管理不当,缺少寿命预测或设备更新改造不合理,人员的培训不足或考核不合格,未制定合理的设备检验维修计划。最后通过钻井现场实例分析,说明管理缺陷对采油管柱落井事故发生的影响。  相似文献   
742.
Uncertain future payoffs and irreversible costs characterize investment in climate change adaptation and mitigation. Under these conditions, it is relevant to analyze investment decisions in a real options framework, as this approach takes into account the economic value associated with investment time flexibility. In this paper, we provide an overview of the literature adopting a real option approach to analyze investment in climate change adaptation and mitigation, and examine how the uncertain impacts of climate change on the condition of the human environment, risk preferences, and strategic interactions among decisions-makers have been modeled. We found that the complex nature of uncertainties associated with climate change is typically only partially taken into account and that the analysis is usually limited to decisions taken by individual risk neutral profit maximizers. Our findings call for further research to fill the identified gaps.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01342-8) contains supplementary material, which is available to authorized users.  相似文献   
743.
Environmental Science and Pollution Research - Digital textile printing (DTP) is a game-changer technology that is rapidly expanding worldwide. On the other hand, process wastewater is rich in...  相似文献   
744.
Environmental Science and Pollution Research - A large amount of fresh tobacco waste with high water content are produced in farmland, and it may cause environmental pollution if it is not properly...  相似文献   
745.
Environmental Science and Pollution Research - To control the dust pollution caused by open-pit coal mining and reduce or avoid the secondary hazards of existing dust suppressants to the...  相似文献   
746.

Copper oxide nanoparticles (CuO NPs) have received considerable attention for their toxic effects on crops and potential application in agriculture. In order to investigate the biological effects of CuO NPs on plants, we exposed cucumber (Cucumis sativus) to two sizes of CuO NPs (510 nm, μCuO and 43 nm, nCuO). Results indicated that with concentration increased, the available Cu content in soil increased significantly. The addition of CuO NPs increased Cu content and other nutrient element (e.g., K, P, Mn, and Zn) content in plants. However, diverse particle sizes had different effects. The nCuO treatment had larger translocation factor, higher nutrient element content in fruits, and lower oxidative damage than μCuO treatment. Moreover, nCuO of 100 mg/kg could stimulate cucumber growth, while μCuO had no obvious effects on growth. Conclusively, CuO NPs could be used as copper fertilizer to supply copper to cucumber. The nCuO had better effects on improving the bioavailability of Cu and nutritional value of fruits. These results can help develop strategies for safe disposal of CuO NPs as agricultural fertilizer.

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We develop estimates of total factor productivity (TFP) change in the New England groundfish fishery from 1964 to 1993, using a procedure similar to Squires' (1992, Rand J. Econom.23(2), 221–236) method, which extends standard TFP measurement by including the effect of fluctuations in stock abundance. The results indicate that TFP increased on average by 4.4% per year from 1964 to 1993. A higher average rate of increase occurred between 1964 and 1982, possibly due to new technologies (e.g., fishfinders). TFP declined at 0.33% annually from 1983 to 1993 due to stringent output and effort control measures.  相似文献   
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