Results 61 to 70 of about 17,541,326 (249)
Shiyou jixie, 2015 针对页岩气“井工厂”的高效开发模式及关键技术，在详细阐述国外“井工厂”钻机技术特点的基础上，介绍了国产钻机在涪陵页岩气示范基地的应用现状，分析了国产钻机在“井工厂”作业中的不足，梳理了国内钻机制造厂商对钻机全方位高效移运技术和钻机自动化升级改造技术的探索研发情况，提出了适合我国今后页岩气开发的“井工厂”钻机一体化解决方案，从而形成适合我国页岩气开发特色的“井工厂”钻机技术。最后指出了页岩气“井工厂”钻机的发展趋势和钻机自动化发展重点。
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FEBS Letters, EarlyView.Plasma membranes contain dynamic nanoscale domains that organize lipids and receptors. Because viruses operate at similar scales, this architecture shapes early infection steps, including attachment, receptor engagement, and entry. Using influenza A virus and HIV‐1 as examples, we highlight how receptor nanoclusters, multivalent glycan interactions ...
Jan Schlegel, Christian Sieben
wiley +1 more source
Shiyou jixie, 2015 为了准确预测大斜度井封隔器解封时的载荷参数，首先进行了装有测力短节的大斜度井管柱解封过程载荷测试，得到了解封过程中钩载及锚定器处轴力的变化规律，然后通过有限元仿真软件，采用测试井管柱及加载参数，建立了大斜度井全井修井管柱数值仿真模型，对该井在解封过程中上提力与锚定器所受载荷的变化情况进行了分析。测试结果与仿真结果对比表明，在解封过程中，当锚定器受力较小时，大钩载荷较直井偏小，但当锚定器所受载荷较大时，大钩载荷较直井偏大。研究内容为解决大斜度井措施管柱力学问题提供了一种新思路。
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FEBS Letters, EarlyView.Ascidian Ciona larvae initially show strong clockwise tail twisting, which is largely corrected during development. However, a small residual twist remains. This study shows that organized helical myofibrils in tail muscles mechanically stabilize this residual asymmetry, preventing complete restoration of bilateral symmetry and revealing how embryos ...
Yuki S. Kogure +3 more
wiley +1 more source
Shiyou jixie, 2015 为了确保连续管在页岩气开发中的高效应用，根据国内油田地域环境特点研制了车载式大容量连续管作业机。整机采用2车装自走式方案，上装设备全液压驱动，主车底盘采用下沉式框架结构，滚筒下沉安装，在满足国内道路运输条件的情况下，尽可能增加连续管容量。该作业机适用连续管外径38.1～50.8 mm，注入头最大提升力360 kN，最高运行速度75 m/min。现场应用结果表明，该设备运行情况良好，取得了良好的经济效益和社会效益，具有广阔的市场应用前景。
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Biophysical approaches for studying viral entry
FEBS Letters, EarlyView.Viruses infect all living organisms and have been responsible for major epidemics and pandemics. Their ongoing evolutionary battle with host defenses creates a constant need for improved tools to study viral behavior. Advancing methods to probe viral attachment, fusion, and genome release deepen our understanding of how infections begin and support the
Inbar Yosibash, Raya Sorkin
wiley +1 more source
Shiyou jixie, 2015 PDC钻头布齿计算是为了确定钻头上各个切削齿在空间中的坐标位置。针对同一优化目标不同的计算方法得出的切削齿位置差别很大，设计出的PDC钻头性能也会截然不同。以近年来国内外PDC钻头布齿设计研究的文献为基础，论述了PDC钻头3原则布齿和力平衡布齿的最新进展，提出了研究中存在的问题。经分析知，PDC钻头布齿设计的计算方法大多以经典3原则为基础，且以等体积为布齿原则进行计算的研究较多；力平衡布齿是PDC钻头稳定性设计的核心，但由于对切削载荷模型研究的限制，其结果与实际差距较大 ...
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The human gut microbiome across the life course
FEBS Letters, EarlyView.Despite significant individual variation and continuous change throughout life, the human gut microbiome follows some life stage‐specific trends. This article provides a brief overview of how gut microbiome composition shifts across different phases of life. Created in BioRender. Özkurt, E. (2026) https://BioRender.com/8q4nrnc.
Alise J. Ponsero +4 more
wiley +1 more source
Shiyou jixie, 2015 大牛地气田部分水平井存在井底出砂现象限制了气井产能，采用常规冲砂工艺时井筒内流体易漏失到地层，造成地层伤害，为此开展了速度管泡沫冲砂工艺技术研究。综合考虑压力、温度、黏度和流体密度的影响，由力平衡原理建立了水平井泡沫临界携砂流速计算模型，经计算得知水平段临界携砂流速是垂直段1.5倍，倾斜段介于两者之间。基于气井泡沫携砂模型，以鄂尔多斯盆地伊陕斜坡东北部的1口水平井DPS-9井为施工试验井，设计了该井施工参数，即井口回压在5.0 MPa内，泡沫液与氮气注入比不超过3∶1，冲砂管柱外径优选为38.1 mm ...
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FEBS Letters, EarlyView.Septin 9 polybasic domains couple phosphoinositide‐rich membrane binding to centrosome positioning, Golgi organization, and microtubule acetylation to control epithelial polarity. Their loss disrupts this axis, causing centrosome mispositioning, Golgi fragmentation, reduced microtubule acetylation, and polarity inversion via upregulation of the ...
Ting ting Cai +4 more
wiley +1 more source