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齿轮传动设计中压力角、齿顶高系数及齿根圆角半径的选择 被引量:3
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作者 李文正 《装备制造技术》 2015年第6期303-304,共2页
齿轮压力角和齿顶高系数及齿根圆角半径也是齿轮设计中的重要参数,本文以渐开线直齿圆柱齿轮为研究对象,提出了在不同工作条件下压力角齿顶高系数及齿根圆角半径的确定,为齿轮参数设计提过参考。
关键词 承载能力 压力重合 齿根圆半径
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空间相位解析的三相并网逆变器不平衡控制策略 被引量:4
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作者 徐友 郑建勇 +1 位作者 梅军 张卿杰 《电工技术学报》 EI CSCD 北大核心 2013年第4期133-139,共7页
鉴于公共电网常处于三相电压不对称运行状态,本文提出一种基于电网电压矢量空间相位解析的并网逆变器不平衡控制新策略。该控制策略通过捕捉电网电压正、负序重合角解析电压和电流正、负序分量的空间相位关系,直接以不平衡的电网电压矢... 鉴于公共电网常处于三相电压不对称运行状态,本文提出一种基于电网电压矢量空间相位解析的并网逆变器不平衡控制新策略。该控制策略通过捕捉电网电压正、负序重合角解析电压和电流正、负序分量的空间相位关系,直接以不平衡的电网电压矢量进行定向并根据常规比例积分(PI)控制器设计了一种新颖比例离散积分控制器,实现对2倍工频的并网电流有功分量和无功分量的零稳态误差控制,且无需计算并网电流正、负序分量,降低了系统计算负荷。实验结果表明,该控制策略可显著抑制电网电压不平衡工况下脉宽调制(PWM)逆变器直流侧电压2次谐波和并网电流畸变。 展开更多
关键词 空间相位解析 重合角 周期延拓 离散积分控制器 零稳态误差 冲击响应不变法
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Texture Analysis of Damascene Copper Interconnects 被引量:2
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作者 王晓冬 吉元 +4 位作者 钟涛兴 李志国 夏洋 刘丹敏 肖卫强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1136-1140,共5页
Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and (111) texture is... Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and (111) texture is the dominate component.As-deposited interconnects undergo the phenomenon of self-annealing at RT,in which some abnormally large grains are found. Lower aspect ratio of lines and anneal treatment procured larger grains and stronger (111) texture. Meanwhile, the intensity proportion of other textures with lower strain energy to (111) texture is decreased. As-deposited specimens reveal (111)(112? and (111) (231) components, (111) (110) component appeared and (111) (112? and (111) (231) components were developed during the annealing process. High angle boundaries are dominant in all specimens, boundaries with a misorientation of 55°-60° and ∑3 ones in higher proportion, followed by lower boundaries with a misorientation of 35°-40° and 29 boundaries. As the aspect ratio of lines and anneal treatment increase,there is a gradual in- crement in ∑3 boundaries and a decrease in ∑9 boundaries. 展开更多
关键词 Cu interconnects TEXTURE MISORIENTATION coincident site lattice boundaries EBSD
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新型数控电火花加工装置的研制
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作者 夏继强 刘晋春 郭永丰 《机械制造》 北大核心 1997年第5期25-27,共3页
研制了数控电火花角相位重合回转加工装置。着重介绍加工装置的机械结构、数控系统及放电状态检测电路,并给出了加工实验的结果。
关键词 数控 相位重合 电火花加工 加工装置
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Effect of hot rolling on microstructure and tribology behaviors of Ti-50.8Ni alloy 被引量:2
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作者 Rui YANG Wei MA +2 位作者 Chao WANG Ting-mei WANG Qi-hua WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第4期967-979,共13页
We link different microstructures to tribological behaviors of Ti-50.8 Ni(mole fraction, %) in reciprocating mode at room temperature(20 ℃). Hot-rolled alloys with B2 phase exhibit lower coefficient of friction and w... We link different microstructures to tribological behaviors of Ti-50.8 Ni(mole fraction, %) in reciprocating mode at room temperature(20 ℃). Hot-rolled alloys with B2 phase exhibit lower coefficient of friction and wear rate compared to the ones with B19?. Stress-induced martensitic transformation occurs during sliding. However, multi-pass hot rolling weakens the wear resistance. In this study, microstructures were characterized through electron backscatter diffraction and transmission electron microscopy(EBSD/TEM). From the concept of energy conservation, the effects of weak intensity of hot-rolled textures on the wear resistance are minimal. Based on the result that the alloy with a higher portion of coincidence site lattice boundaries shows lower martensitic start transformation temperature in the DSC curves than that with higher KAM values, the delay on B2-B19? transformation from {112}B2 twins outweighs dislocations. Moreover, widely distributed small-angle grain boundaries owing to dynamic recovery improve the wear resistance effectively compared to those that are well-recrystallized. 展开更多
关键词 Ti-50.8Ni alloy tribological performance small angle grain boundaries coincidence site lattice(CSL)boundary
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Intra-corporeal delta-shaped anastomosis in laparoscopic right hemicolectomy for right colon cancer:a safe and effective technique 被引量:1
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作者 Hao Su Wei-Sen Jin +6 位作者 Peng Wang Mandula Bao Xue-Wei Wang Qian Liu Xi-Shan Wang Zhi-Xiang Zhou Hai-Tao Zhou 《Gastroenterology Report》 SCIE EI 2019年第4期272-278,I0002,共8页
Background and objective:Intra-corporeal delta-shaped anastomosis(IDA)is an important development in laparoscopic digestive-tract reconstruction.We applied it in laparoscopic right hemicolectomy for right colon cancer... Background and objective:Intra-corporeal delta-shaped anastomosis(IDA)is an important development in laparoscopic digestive-tract reconstruction.We applied it in laparoscopic right hemicolectomy for right colon cancer and compared the short-term outcomes between the patients treated with IDA and conventional extracorporeal anastomosis(EA).Methods:Between 1 January 2016 and 1 October 2017,36 and 50 patients who underwent IDA and EA,respectively,were included.Data on clinicopathological characteristics,surgical outcomes,post-operative recovery and complications were collected and compared between the two groups.Results:Surgical outcomes and clinicopathological characteristics were similar between the two groups except the length of incision,which was significantly shorter in the IDA group than in the EA group(4.660.6 vs 5.660.7 cm,P<0.001).The time to ground activities,fluid diet intake and post-operative hospitalization did not differ between the groups;however,the time to first flatus was significantly shorter in the IDA group than in the EA group(2.860.5 vs 3.260.8 days,P=0.004).The post-operative visual analogue scale for pain was lower in the IDA group than in the EA group on post-operative Day 1(4.060.7 vs 4.561.0,P=0.002)and post-operative Day 3(2.760.6 vs 3.460.6,P<0.001).The surgical complication rates were 8.3 and 16.0%in the IDA and EA groups(P=0.470),respectively.No complications such as anastomotic bleeding,stenosis and leakage occurred in any patient.Conclusions:IDA is safe and feasible and shows more satisfactory short-term outcomes than EA. 展开更多
关键词 Colon cancer delta-shaped anastomosis intra-corporeal anastomosis digestive-tract reconstruction laparoscopic right hemicolectomy
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