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991.
利用数值模拟方法对不同阻尼比条件下Spar式浮式风力机基础结构进行涡激运动特性的研究.从涡激运动响应幅值、频率比、位移、升力及拖曳力等方面研究Spar式浮式风力基础结构涡激运动的关键特性.研究表明:涡激运动上端分支对应的频率比为fy/fn≈1,且该分支出现最大幅值.随着阻尼比的增大,上端分支约化速度范围有减小趋势.低阻...  相似文献   
992.
993.
通过使用Apollonius保角变换和Fourier级数方法,获得了静止流场中汽泡生长过程中的诱导速度场。  相似文献   
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996.
Under the tensile loading, the damage of metals in the corrosive medium is the most destructive and harmful. In this study, the stress corrosion cracking behavior of H-charged high-strength steel in 3.5 wt% NaCl solution after electropulsing treatment was investigated. The experimental results from elongation, yield strength, fracture morphology, and polarization curves all demonstrate the positive effect of the pulsed processing, as it reduced the susceptibility of steel to stress corrosion cracking by removing hydrogen by electropulsing. The reduction in hydrogen content of the pulsed high–strength steels was attributed to electromigration and increased system free energy, which drove the hydrogen atoms in the steel to de–trap and reduced the susceptibility to stress corrosion cracking.  相似文献   
997.
肿瘤对人类健康造成很大威胁。化疗作为一种全身性的治疗方法,在肿瘤治疗中的地位不可动摇。化疗所致恶心呕吐(chemotherapy induced nausea and vomiting, CINV)是化疗过程中常见的不良反应,严重影响了患者的情绪、生活质量和肿瘤的控制。CINV的防治对肿瘤患者来说非常重要。托烷司琼是较常用的5-羟色胺Ⅲ亚型(5-hydroxytryptamine type 3, 5-HT3)受体拮抗剂,在防治CINV方面具有很好的临床效果,但仍有部分患者使用托烷司琼后效果不佳。越来越多的研究表明这些个体差异可能与基因多态性密切相关。本文就细胞色素P450 2D6(cytochrome P450 2D6, CYP2D6)基因多态性对托烷司琼预防CINV效果的影响作一综述,以期为基因多态性指导下的临床个体化用药提供思路。  相似文献   
998.
An intrinsic hydrogenated amorphous silicon (a-Si:H(i)) film and a doped silicon film are usually combined in the heterojunction contacts of silicon heterojunction (SHJ) solar cells. In this work, a post-doping process called catalytic doping (Cat-doping) on a-Si:H(i) is performed on the electron selective side of SHJ solar cells, which enables a device architecture that eliminates the additional deposition of the doped silicon layer. Thus, a single phosphorus Cat-doping layer combines the functions of two other layers by enabling excellent interface passivation and high carrier selectivity. The overall thinner layer on the window side results in higher spectral response at short wavelengths, leading to an improved short-circuit current density of 40.31 mA cm−2 and an efficiency of 23.65% (certified). The cell efficiency is currently limited by sputter damage from the subsequent transparent conductive oxide fabrication and low carrier activation in the a-Si:H(i) with Cat-doping. Numerical device simulations show that the a-Si:H(i) with Cat-doping can provide sufficient field effect passivation even at lower active carrier concentrations compared to the as-deposited doped layer, due to the lower defect density.  相似文献   
999.
Grounding wires and enclosed ZnO elements have been incorporated generally in 6.6‐kV distribution systems by TEPCO for the reduction of lightning overvoltages. At present, the reliability to lightning surges is tolerably good. However, the facility of grounding wires is not inexpensive and its maintenance is hard due to corrosion and disconnection in some areas. A typical model simulating TEPCO field adopting enclosed ZnO elements has been developed and we have evaluated relative failure risks systematically according to conditions with and without grounding wires against lightning overvoltages. Two kinds of failures discussed in the paper are the flashover of insulation and the overduty of ZnO elements, and two kinds of induced and direct lightning overvoltages are studied in flashover. The greatest problem with no grounding wire is the increase of ZnO elements' duty, but it was demonstrated that a short partial grounding wire around ZnO elements or the selection of heavier ZnO elements provides a solution. The main objectives of this study are to clarify the relative failure risks systematically according to realistic field conditions, the risk of small stroke currents having long duration to ZnO elements' duty, and countermeasures against ZnO elements' overduty. © 1999 Scripta Technica, Electr Eng Jpn, 127(1): 1–10, 1999  相似文献   
1000.
Cation‐exchange hollow fiber membrane was prepared by radiation‐induced grafting polymerization of styrene onto polyethylene hollow fiber membrane and its sulfonation. Adsorption characteristics for the cation‐exchange membranes are examined when the solution of Co2+ permeates across the cation‐exchange fiber membrane. The maximum grafting peak was obtained from 70% styrene concentration at 50°C. The degree of grafting (%) was enhanced with additives such as H2SO4 and divinylbenzene. The content of  SO3H groups ranged from 2 to 5 mmol g−1 with chlorosulfonic acid (ClSO3H) in dichloroethane, from 0.5 to 6 mmol g−1 with ClSO3H in H2SO4, respectively. The adsorption of Co2+ by the cation‐exchange membranes increased with increasing  SO3H content. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2227–2235, 1999  相似文献   
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