Results 21 to 30 of about 9,201 (116)
ABSTRACT For over 30 years, the northern Mexican state of Chihuahua bordering Texas and New Mexico has experienced and witnessed multiple forms of violence across its rural and urban regions. Communities are besieged with cartel and gender‐based violence and the saturation of international corporations that pay less than livable wages for workers in ...
Sylvia Fernández Quintanilla +1 more
wiley +1 more source
Abstract Collaboration in governing complex environmental challenges is the norm. However, collaboration does not necessarily deliver desirable outcomes, and the importance of forming collaborative networks that effectively address the challenges at hand has been emphasized in theory and practice.
Per Becker, Örjan Bodin
wiley +1 more source
Occurrences of dust storms and long‐distance movement of dust across landscapes is constantly increasing in south Asia. This dust is expected to have profound impact on vegetation health and sustainability as dust may contribute to nutrient budgets of the forest ecosystems, while it could impart various stresses to the plants.
Shree P. Pandey +2 more
wiley +1 more source
Abstract Despite the reality that advocates frequently expend significant resources to pass symbolic policies, this policy design has often been neglected by policy studies scholarship. We combine policy design and policy feedback theory to examine this oft overlooked policy design in practice using the case of California's human right to water law ...
Jenny Linder Rempel +1 more
wiley +1 more source
ABSTRACT Objectives Our aim was to examine the prenatal profiles of pregnancies affected by an atypical chromosomal aberration, focusing on pathogenic copy‐number variants (pCNVs). We also wanted to quantify the performance of combined first‐trimester screening (cFTS) and a second‐trimester anomaly scan in detecting these aberrations. Finally, we aimed
K. Gadsbøll +6 more
wiley +1 more source
冀东油田目前主要通过同位素法测吸水剖面来认识注水井的分层吸水状况,这种方法无法测出各不同渗透率小层的启动压力,测试结果不能有效指导注水井分注段的合理划分,为此开展了不动管柱分层测试工艺管柱研究。该管柱主要由液压安全接头、水力锚、测试阀、卡水封隔器和伸缩管等组成,通过卡水封隔器将所有待测层卡分开来,再经投球憋压控制测试阀自下而上逐层开启同时关闭下一层后进行测试,一趟管柱可完成3~5层施工。现场应用结果表明,该测试工艺管柱结构简单,坐封可靠,易于操作,测试数据真实反映了小层启动压力和吸水能力 ...
王金忠
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目前的大斜度井和水平井分层注水管柱无法进行钢丝电缆作业,传统测调工艺无法实施,导致分层注水合格率较低。鉴于此,研究了电缆永置式井下测调技术,提出了一种适用于大斜度井和水平井分层注水的新工艺。采用该工艺可以实时监测注水层位,实现注水量的自动调节,无需钢丝电缆作业,解决了井斜超过60°井的测试调配问题;采用预置电缆技术,将测试组件与调节组件集成在井下测调工作筒内,可以实时对井下数据进行监测与控制。试验及应用结果表明,该工艺不受井斜限制,可以实现分层调配、参数实时监测和直读式验封,提高了作业效率 ...
doaj
针对层间吸水差异较大的分注井中高渗层注水存在节流压差不够、调配不准及配水器刺坏等问题,研制了预节流防刺配水器。该配水器设计了3级节流方式,具有节流压差调节范围大、可防返吐等特点;同时采用组合活塞结构增强配水器的防刺效果,延长了大压差分注井中配水器的调配周期和有效使用寿命。该配水器已现场应用8井次,一次性施工成功率100%。应用结果表明,该预节流防刺配水器原理可靠、结构合理,在对高渗层实现大压差控制的同时,还增强了配水器防刺注水效果,大压差分注井的层段合格率由原来的50.0%提升至87.5%。
张一羽 +4 more
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目前我国分层注水工艺存在工作原理及结构复杂、分层注水管柱工艺繁琐等问题。为此,提出了一种新型井下螺杆驱动型分层注水系统。该注水系统采用螺杆马达驱动螺杆泵,动力液利用分流器分流,分别进入马达与泵,运转时马达降压,泵增压,分别注入不同油层。对螺杆泵与马达匹配的原理及方案进行了研究,得到了整个系统匹配的详细计算过程,同时设计了匹配实例,得到了1∶2头螺杆泵与2∶3头螺杆马达的合理匹配参数。实例中,随着泵压由0.70 MPa增大到4.20 MPa,马达压降由0.89 MPa增大到5.36 MPa ...
李增亮 +5 more
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针对同心多管分注工艺存在管柱不具备洗井功能和不具有井控保护能力的缺点,研究开发了海上同心多管分注洗井防溢流工艺技术。该技术可实现地面直接调节各层注入量,精确控制各层注水量,有效解决大斜度井无法钢丝作业的分注问题;多通道精确注水,有效解决多介质注入问题;能实现不动井口条件下的管柱提升,建立洗井通道,有效解决海上油田注水井洗井不方便、反洗通道易堵塞、反洗排量小、反洗不彻底等技术难题,通过定期活动注水管柱,避免管柱遇卡,减少大修作业;同时可避免注水井停注时液体返出问题,有效地解决了井下安全控制问题 ...
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