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51.
Jeris A. Danielson A. Raziq Qazi 《Journal of the American Water Resources Association》1972,8(2):359-366
The agricultural production from the Lower South Platte Basin in Colorado represents a significant portion of the state economy. Until the early 1950's the production had developed almost exclusively by use of river water. Drought conditions combined with improved well technology resulted in an inordinate amount of well development in the valley during the period 1952-56. These wells were used for supplemental supply in many cases, but the application of sprinkler irrigation brought many acres of here-to-fore dry land into irrigated production. As a result of the vast amounts of groundwater withdrawal by the newly developed wells, senior surface appropriators found a decreasing amount of water available for use in the streams. The legislature, observing the doctrine of prior appropriation, ruled that all surface and ground water in a tributary would be treated and administered as one resource. This, of course, spelled doom for the well-oriented segment of the economy. Analysis of a segment of the river on an inflow-outflow basis was made with careful determination of all inflow-outflow in the study reach to include correlations required to determine ungaged side-channel in-flow and unmetered irrigation wells. Results indicate that wells have intercepted normal return flows to the river resulting in a decreased amount of surface water during the irrigation season. Stream depletion appears to equal the expected consumptive use of well water which ranged between 40% to 50% of the groundwater extraction. 相似文献
52.
废钻井液、泥浆的处理与控制对策 总被引:2,自引:0,他引:2
赵荣峰 《安全.健康和环境》2006,6(5):32-33
介绍中原油田分公司实施源头控制,减少废钻井液产生和利用无害化技术处理钻井废弃泥浆的实践,分析存在的主要问题,提出减少废钻井液产生的控制对策. 相似文献
53.
We undertake three objectives in this Incubator. We begin with a discussion of how well‐being has been considered in organizational research. Second, we provide an overview of the relationship between employee well‐being and such workplace outcomes as job performance, employee retention, and cardiovascular health. Third, we introduce exciting research directions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
54.
针对深水钻井作业过程中的井喷溢油问题,基于计算流体力学(CFD)方法,通过UDF函数给定海流流剖面、波浪入口边界条件和海水静压分布情况,结合标准k-ε方程,采用VOF模型实现对油、气、水三相自由面的追踪,建立了溢油扩散事故数值仿真模型,评估深水条件下溢油扩散危害区域,研究海流流速、溢油量对原油扩散的影响。结果表明,海流流速和溢油量是原油扩散行为和危害区域分布范围的重要影响因素。 相似文献
55.
Emerging conservation challenges and prospects in an era of offshore hydrocarbon exploration and exploitation
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Globally, extensive marine areas important for biodiversity conservation and ecosystem functioning are undergoing exploration and extraction of oil and natural gas resources. Such operations are expanding to previously inaccessible deep waters and other frontier regions, while conservation‐related legislation and planning is often lacking. Conservation challenges arising from offshore hydrocarbon development are wide‐ranging. These challenges include threats to ecosystems and marine species from oil spills, negative impacts on native biodiversity from invasive species colonizing drilling infrastructure, and increased political conflicts that can delay conservation actions. With mounting offshore operations, conservationists need to urgently consider some possible opportunities that could be leveraged for conservation. Leveraging options, as part of multi‐billion dollar marine hydrocarbon operations, include the use of facilities and costly equipment of the deep and ultra‐deep hydrocarbon industry for deep‐sea conservation research and monitoring and establishing new conservation research, practice, and monitoring funds and environmental offsetting schemes. The conservation community, including conservation scientists, should become more involved in the earliest planning and exploration phases and remain involved throughout the operations so as to influence decision making and promote continuous monitoring of biodiversity and ecosystems. A prompt response by conservation professionals to offshore oil and gas developments can mitigate impacts of future decisions and actions of the industry and governments. New environmental decision support tools can be used to explicitly incorporate the impacts of hydrocarbon operations on biodiversity into marine spatial and conservation plans and thus allow for optimum trade‐offs among multiple objectives, costs, and risks. 相似文献
56.
自动化压井是指计算机能够按照一定的控制原则独立完成压井的1种方法。为了验证自动化压井系统的可行性和平稳性,开展了多种不同程度的试验井气侵模拟,利用自动化压井系统进行司钻法自动化压井操作试验,成功实施了司钻法第1循环周压井。研究结果表明:自动化压井系统能够实时获取和分析溢流参数,迅速准确生成压井施工单,对节流控制箱实施远程控制并完成节流阀开度的调整;在不同气侵程度下,自动化压井系统能够按照压井设计曲线将立压稳定控制在目标值附近;在气侵气体向上运移和排出井口的过程中,井底压力波动远小于人工压井所产生的压力波动。该项研究基本验证了自动化压井系统在钻井井场应用的可行性。 相似文献
57.
废钻井液污染分析及处理方法的探讨 总被引:7,自引:2,他引:5
为解决废钻井液对周围环境的污染,介绍了废钻井液的成分及对环境的影响,分析了国内外废钻井液处理方法的优缺点,详细阐述了中原油田结合本单位情况,用无害化处理技术处理废钻井液的方法和效果。试验表明:无害化处理剂中的各组分与废钻井液中各污染因子发生化学和物理作用,经3~5个月固化后可以达到无害化处理的目的。分析认为:中原油田钻井废弃物无害化处理技术是切实可行的。 相似文献
58.
《组织行为杂志》2017,38(6):856-875
This paper introduces a social identity perspective to job insecurity research. Worrying about becoming jobless, we argue, is detrimental because it implies an anticipated membership of a negatively evaluated group—the group of unemployed people. Job insecurity hence threatens a person's social identity as an employed person. This in turn will affect well‐being and job performance. A three‐wave survey study amongst 377 British employees supports this perspective. Persons who felt higher levels of job insecurity were more likely to report a weaker social identity as an employed person. This effect was found to be stable over time and also held against a test of reverse causality. Furthermore, social identity as an employed person influenced well‐being and in‐role job performance and mediated the effect of job insecurity on these two variables over time. Different to the expectations, social identity as an employed person and organisational proactivity were not connected. The findings deliver interesting evidence for the role of social identity as an employed person in the relationships between job insecurity and its consequences. Theoretically, this perspective illustrates the individual and group‐related nature of job insecurity and offers a novel way of connecting work situations with individual well‐being, behaviour and attitudes. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
59.
60.
钻井废弃物治理技术的研究 总被引:1,自引:0,他引:1
阐述了东辛采油厂钻井废弃物来源及其处理现状,介绍了几种现有钻井废弃物处理工艺,在钻井废弃物治理技术上进行了探索与实践。 相似文献