Results 61 to 70 of about 26,640,317 (249)
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。
doaj
FEBS Letters, EarlyView.The Ile181Asn variant of human UDP‐xylose synthase (hUXS1), associated with a short‐stature genetic syndrome, has previously been reported as inactive. Our findings demonstrate that Ile181Asn‐hUXS1 retains catalytic activity similar to the wild‐type but exhibits reduced stability, a looser oligomeric state, and an increased tendency to precipitate ...
Tuo Li +2 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。
doaj
FEBS Letters, EarlyView.We reconstituted Synechocystis glycogen synthesis in vitro from purified enzymes and showed that two GlgA isoenzymes produce glycogen with different architectures: GlgA1 yields denser, highly branched glycogen, whereas GlgA2 synthesizes longer, less‐branched chains.
Kenric Lee +3 more
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 ...
doaj
FEBS Letters, EarlyView.We identified a systemic, progressive loss of protein S‐glutathionylation—detected by nonreducing western blotting—alongside dysregulation of glutathione‐cycle enzymes in both neuronal and peripheral tissues of Taiwanese SMA mice. These alterations were partially rescued by SMN antisense oligonucleotide therapy, revealing persistent redox imbalance as ...
Sofia Vrettou, Brunhilde Wirth
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 ...
doaj
FEBS Letters, EarlyView.In this study, we found that human cervical‐derived adipocytes maintain intracellular iron level by regulating the expression of iron transport‐related proteins during adrenergic stimulation. Melanotransferrin is predicted to interact with transferrin receptor 1 based on in silico analysis.
Rahaf Alrifai +9 more
wiley +1 more source
Shiyou jixie, 2015 卡箍式水下连接器稳定的着陆过程将有效减小着陆时连接器对密封圈的冲击，进而避免密封失效。通过Matlab仿真软件对连接器缓冲机构进行建模，针对其关键环节进行多参数模拟。模拟结果表明，由液压系统组成的缓冲机构能够有效起到缓冲连接器平稳着陆的效果，相比没有缓冲机构的连接器着陆时的冲击减小90%；缓冲机构中节流阀对缓冲机构液压系统起到了保证压力平稳的作用，当其开度为200 mm2时缓冲效果最好，稳定时间缩短70%；减压阀能够有效降低接触时液压系统的压力峰值，当调定压力为20 ...
doaj
FEBS Letters, EarlyView.Structural and biochemical characterisations show that the planar cell polarity (PCP) protein Inturned harbours a unique PDZ‐like domain that does not bind canonical PDZ‐binding motifs (PBMs) like that of another PCP protein Vangl2. In contrast, the apical‐basal polarity protein Scribble contains four PDZ domains that bind Vangl2, but one PDZ domain ...
Stephan Wilmes +4 more
wiley +1 more source