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Prolonged penile strangulation with metal clamps 被引量:4
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作者 Chirag Patel Richard Kim Michael Delterzo 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期105-106,共2页
Various different objects have been reported to strangulate the penis,We reported on a patient who used metal radiator clamps for an extended period of time .Workup included history,physical examination and urinalysis... Various different objects have been reported to strangulate the penis,We reported on a patient who used metal radiator clamps for an extended period of time .Workup included history,physical examination and urinalysis.The patient was taken to the operating room for further evaluation with cystourethroscopy and orthopedic wire cutters were used to break the metal bands.(Asian J Androl 2006Jan;8:105-106) 展开更多
关键词 penis penile strangulation metal clamps
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A Comparison Study of Diode-String ESD Clamps for CMOS Input Protection
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作者 Jin Young Choi 《Circuits and Systems》 2019年第2期21-36,共16页
Based on 2-D device simulations and mixed-mode transient simulations, DC and transient discharge characteristics of a usual diode string utilizing a standard CMOS process, and a diode string utilizing a triple-well CM... Based on 2-D device simulations and mixed-mode transient simulations, DC and transient discharge characteristics of a usual diode string utilizing a standard CMOS process, and a diode string utilizing a triple-well CMOS process, which can serve as an essential VDD-VSS clamp device for CMOS input ESD protection were compared. Transient discharge characteristics including peak voltages developed across gates oxides of transistors in input buffers, lattice heating inside ESD protection devices, and ratios of discharge current components at its peak inside the diode-string clamp were compared. DC standby current levels added per each input pad structure, which are the critical parameters determining usefulness of the devices, were also compared. We showed that the diode-string devices in comparison can serve successfully as a VDD-VSS clamp device for ESD protection by virtue of the dominant pnpn thyristor-related conduction mechanisms. Optimization of design parameters including anode-cathode contact spacing in each diode in the string, device width of the diode string, and number of diodes in the diode string was performed to present transient discharge and DC characteristics of some recommendable design examples, which can serve as a guideline in designing diode-string clamp devices. 展开更多
关键词 ESD INPUT PROTECTION DIODE STRING clamp CMOS
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The Rapid Development of Technology in Making Iron Clamps of Three Ancient Temples in the Archaic and Classical Period
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作者 George Varoufakis 《Journal of Chemistry and Chemical Engineering》 2012年第12期1136-1141,共6页
A few years ago, the present author had the opportunity to study the iron clamps of the archaic and classical temples. This research led to very interesting results concerning the development of technology applied in ... A few years ago, the present author had the opportunity to study the iron clamps of the archaic and classical temples. This research led to very interesting results concerning the development of technology applied in making those clamps and what is more its rapid evolution in a very short period. For instance, the technology in making the clamps of Parthenon and those of the Epikourios Apollo differs completely, although the latter was erected by the same engineer, Iktinos. Actually, it is a revolutionary one as compared with that applied in the erection of Parthenon. The paper starts by examining the making of the archaic Trapeza iron clamps and continue with those of the Parthenon and the Epikourios Apollo. 展开更多
关键词 Iron clamps archaic temples classical temples development in technology macro micro examination.
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Comparison of nonlinear modeling methods for the composite rubber clamp
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作者 Yiming CAO Hui MA +4 位作者 Xumin GUO Bingfeng ZHAO Hui LI Xin WANG Bing WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期763-778,共16页
The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.B... The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.By fitting the identified nonlinear coefficients under different excitation amplitudes,the nonlinear vibration responses of the system are predicted.The results show that the accuracy of the BWM is higher than that of the CSFM,especially in the non-resonant region.However,the optimization time of the BWM is longer than that of the CSFM. 展开更多
关键词 pipeline system nonlinear clamp model composite rubber clamp amplitude-dependent characteristic vibration response experiment
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Effect of an Airbag-selective Portal Vein Blood Arrester on the Liver after Hepatectomy:A New Technique for Selective Clamping of the Portal Vein
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作者 Ce-xiong FU Xiao-ri QIN +6 位作者 Jin-song CHEN Jie ZHONG Yu-xu XIE Bi-dan LI Qing-qing FU Fang LI Jin-fang ZHENG 《Current Medical Science》 SCIE CAS 2024年第2期380-390,共11页
Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic s... Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic space-occupying lesions.Methods:Rabbits undergoing hepatectomy were randomly assigned to 4 groups:intermittent portal triad clamping(PTC),intermittent portal vein clamping(PVC),intermittent portal vein blocker with an airbag-selective portal vein blood arrester(APC),and without portal blood occlusion(control).Hepatic ischemia and reperfusion injury were assessed by measuring the 7-day survival rate,blood loss,liver function,hepatic pathology,hepatic inflammatory cytokine infiltration,hepatic malondialdehyde levels,and proliferating cell nuclear antigen levels.Results:Liver damage was substantially reduced in the APC and PVC groups.The APC animals exhibited transaminase levels similar to or less oxidative stress damage and inflammatory hepatocellular injury compared to those exhibited by the PVC animals.Bleeding was significantly higher in the control group than in the other groups.The APC group had less bleeding than the PVC group because of the avoidance of portal vein skeletonization during hepatectomy.Thus,more operative time was saved in the APC group than in the PVC group.Moreover,the total 7-day survival rate in the APC group was higher than that in the PTC group.Conclusion:Airbag-selective portal vein blood arresters may help protect against hepatic ischemia and reperfusion injury in rabbits undergoing partial hepatectomy.This technique may also help prevent liver damage in patients requiring hepatectomy. 展开更多
关键词 HEPATECTOMY portal vein hepatic damage selective clamping
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膜片箝pClamp采样软件中的P/N漏减分析 被引量:7
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作者 刘振伟 李立君 刘传缋 《生理学报》 CAS CSCD 北大核心 2000年第5期440-443,共4页
本文采用大鼠海马脑片盲法的全细胞记录技术 ,研究了Axon公司pClamp采样软件Clampex中P/N漏减的功能意义和作用机制 ,对P/N漏减脉冲电流的采集以及漏减脉冲的时间、极性、箝位电压、数目、位置等参数的设置进行了详细分析。结果表明 ,... 本文采用大鼠海马脑片盲法的全细胞记录技术 ,研究了Axon公司pClamp采样软件Clampex中P/N漏减的功能意义和作用机制 ,对P/N漏减脉冲电流的采集以及漏减脉冲的时间、极性、箝位电压、数目、位置等参数的设置进行了详细分析。结果表明 ,在采集电压门控性离子通道电流时 。 展开更多
关键词 漏减 膜片箝 海马脑片
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具有sliding-clamped端强阻尼屈曲梁方程整体解的存在性
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作者 王旦霞 阎思卿 张建文 《太原理工大学学报》 CAS 北大核心 2009年第4期437-439,共3页
对固体力学中提出的具有强阻尼效应的非线性粘弹性梁方程进行了研究。在给定具有sliding-clamped端和简支端的边界条件下,利用Galerkin方法,证明了该非线性梁方程的整体弱解和强解的存在性。
关键词 sliding—clamped端 简支端 强阻尼 弱解 强解
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The calculation of the Reproducibility Error in the technological system with the clamp on the gas power
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作者 沈兴东 郑士成 《自动化博览》 2011年第S2期169-172,共4页
The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and ... The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and analyzed its influencing factor with examples,the Reproducibility Error law:\ The larger the diameter of the cylinder,the smaller the error; the slower the tool speed,(k values smaller),the smaller the error. 展开更多
关键词 CYLINDER clampING REPRODUCIBILITY ERROR TRANSFER function ovality
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重复经颅磁刺激对阿尔茨海默病小鼠海马齿状回钾离子通道的影响
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作者 钱磊 于洪丽 +1 位作者 赵秀芝 朱俞灿 《中国组织工程研究》 CAS 北大核心 2025年第12期2544-2552,共9页
背景:经颅磁刺激已经被用于治疗阿尔茨海默病,但其机制尚未完全明确。目的:分析重复经颅磁刺激对阿尔茨海默病小鼠海马齿状回神经兴奋性的作用机制。方法:采用随机数字表法,将16只C57BL/6小鼠随机分为对照组(n=8)、对照+磁刺激组(n=8),... 背景:经颅磁刺激已经被用于治疗阿尔茨海默病,但其机制尚未完全明确。目的:分析重复经颅磁刺激对阿尔茨海默病小鼠海马齿状回神经兴奋性的作用机制。方法:采用随机数字表法,将16只C57BL/6小鼠随机分为对照组(n=8)、对照+磁刺激组(n=8),将16只APP/PS1小鼠随机分为痴呆组(n=8)、痴呆+磁刺激组(n=8),对照+磁刺激组与痴呆+磁刺激组给予重复经颅磁刺激,2 h/d,连续刺激14 d。磁刺激结束后,采用水迷宫实验检测小鼠认知能力,全细胞膜片钳技术采集动作电位,分析阿尔茨海默病对动作电位的影响;全细胞膜片钳技术采集钾离子通道电流,分析其动力学特性对神经兴奋性的作用。结果结论:①水迷宫实验结果显示,正常小鼠接受重复经颅磁刺激后能够更加精准地找到确定原平台位置,阿尔茨海默病导致小鼠学习记忆能力下降,找到平台次数下降,海马齿状回神经元退化,而重复经颅磁刺激可提高阿尔茨海默病小鼠的学习记忆能力;②全细胞膜片钳技术检测结果显示,重复经颅磁刺激能够使阿尔茨海默病小鼠神经元更容易发生去极化,使神经元更易兴奋;③钾离子通道电流分析结果显示,阿尔茨海默病使得瞬时外向钾通道半数激活电压增大,失活曲线向着去极化方向偏移,复活时间常数延长,使得延迟整流钾通道激活曲线向着去极化的方向偏移,而重复经颅磁刺激干预延迟了钾离子通道的打开与关闭,抑制了细胞内钾离子的外流,使得细胞内保持较高浓度K^(+),提高了神经元兴奋性;④结果表明,重复经颅磁刺激可能通过提高海马齿状回颗粒神经元兴奋性来缓解认知能力的衰退。 展开更多
关键词 重复经颅磁刺激 全细胞膜片钳 K+通道 水迷宫 神经兴奋性 学习记忆 动作电位
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Study on Loading Leaves Density with Cage Clamp on Quality of Cured Tobaccos in Bulk-Curing Barn
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作者 王能如 余金恒 +2 位作者 罗荣欣 林北森 尹永强 《Agricultural Science & Technology》 CAS 2014年第8期1317-1321,共5页
In order to determine the best loading density of tobacco leaf with cage clamp in bulk-curing barns, a curing test was conducted on middle-part tobacco leaves. The results showed that for good appearance quality of cu... In order to determine the best loading density of tobacco leaf with cage clamp in bulk-curing barns, a curing test was conducted on middle-part tobacco leaves. The results showed that for good appearance quality of cured tobacco, the loading density at 59.52 kg/m2 (4 000 kg/barn) was the best, fol owed by 66.96 kg/m2 (4 500 kg/barn) and 74.40 kg/m2 (5 000 kg/barn). As leaf loading density increased, the contents of leaf nicotine and total nitrogen increased, sugar content had smal changes, the ratio of sugar to nicotine decreased and tended to be balanced and the content of neutral aroma substances was decreasing, but the difference among treatments was not significant. With the increase of loading density, the sensory quality of cured leaf was better. When leaf loading density was 66.96 kg/m2 (4 500 kg/barn), apperance quality of cured leaf improved considerably, with prominent aro-ma. Therefore, the best loading density of tobacco leaf in cage clamp of bulk-curing barn would be 66.96 kg/m2 (4 500 kg/barn) . 展开更多
关键词 Flue-cured tobacco Bulk curing Tobacco quality Cage clamp Loadingleaves density
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基于Clamped B样条的空间非合作目标抓捕策略研究 被引量:4
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作者 王明明 罗建军 余敏 《力学学报》 EI CAS CSCD 北大核心 2021年第2期524-538,I0004,共16页
空间机械臂技术是未来实施在轨服务与维护任务的关键技术之一.利用机械臂对空间非合作目标,特别是翻滚目标的抓捕仍然存在巨大的挑战.本文提出一种基于Clamped B样条的空间非合作目标抓捕策略方案.在对非合作目标与空间机械臂运动学与... 空间机械臂技术是未来实施在轨服务与维护任务的关键技术之一.利用机械臂对空间非合作目标,特别是翻滚目标的抓捕仍然存在巨大的挑战.本文提出一种基于Clamped B样条的空间非合作目标抓捕策略方案.在对非合作目标与空间机械臂运动学与动力学分析的基础上,结合非合作目标被空间机械臂抓捕后的动静态对偶性分析,构建抓捕后的力可操作度椭球作为抓捕策略设计的优化指标.其次,考虑目标的运动预测和空间机械臂的抓捕能力图谱构建,确定空间机械臂应对目标的最优抓捕时机与抓捕终端状态.基于Clamped B样条对空间机械臂各关节轨迹进行时间归一化参数描述,并对抓捕过程中的机械臂关节角、速度、避撞、抓捕走廊等约束进行数学变换,最终将抓捕策略转换为多约束、多目标的非线性优化问题,利用自适应惯性权重的粒子群优化算法进行求解.将所设计的抓捕策略应用于空间七自由度运动学冗余机械臂,实现了对空间中翻滚目标的成功捕获,验证了所提抓捕策略的可行性与有效性. 展开更多
关键词 抓捕策略 clamped B样条 空间机械臂 抓捕能力图谱
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Plastic Mechanism of Multi-pass Double-roller Clamping Spinning for Arc-shaped Surface Flange 被引量:3
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作者 FAN Shuqin ZHAO Shengdun +1 位作者 ZHANG Qi LI Yongyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第6期1127-1137,共11页
Compared with the conventional single-roller spinning process, the double-roller clamping spinning(DRCS) process can effectively prevent the sheet metal surface wrinkling and improve the the production efficiency an... Compared with the conventional single-roller spinning process, the double-roller clamping spinning(DRCS) process can effectively prevent the sheet metal surface wrinkling and improve the the production efficiency and the shape precision of final spun part. Based on ABAQUS/Explicit nonlinear finite element software, the finite element model of the multi-pass DRCS for the sheet metal is established, and the material model, the contact definition, the mesh generation, the loading trajectory and other key technical problems are solved. The simulations on the multi-pass DRCS of the ordinary Q235A steel cylindrical part with the arc-shaped surface flange are carried out. The effects of number of spinning passes on the production efficiency, the spinning moment, the shape error of the workpiece, and the wall thickness distribution of the final part are obtained. It is indicated definitely that with the increase of the number of spinning passes the geometrical precision of the spun part increases while the production efficiency reduces. Moreover, the variations of the spinning forces and the distributions of the stresses, strains, wall thickness during the multi-pass DRCS process are revealed. It is indicated that during the DRCS process the radical force is the largest, and the whole deformation area shows the tangential tensile strain and the radial compressive strain, while the thickness strain changes along the generatrix directions from the compressive strain on the outer edge of the flange to the tensile strain on the inner edge of the flange. Based on the G-CNC6135 NC lathe, the three-axis linkage computer-controlled experimental device for DRCS which is driven by the AC servo motor is developed. And then using the experimental device, the Q235A cylindrical parts with the arc-shape surface flange are formed by the DRCS. The simulation results of spun parts have good consistency with the experimental results, which verifies the feasibility of DRCS process and the reliability of the finite element model for DRCS. 展开更多
关键词 SPINNING double-roller clamping MULTI-PASS arc-shaped surface
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Analysis of Strain Clamp Failure on 500 kV Transmission Line 被引量:4
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作者 Mingcheng Sun Che Tan +2 位作者 Chaoqun Zhang Chao Yang Hongqiang Li 《Journal of Materials Science and Chemical Engineering》 2018年第4期47-56,共10页
In this work, the main reasons for the breakage of 500 kV transmission line are studied. Under low temperature condition, the coverage of the ice results in the disconnection between the aluminum tube and the steel an... In this work, the main reasons for the breakage of 500 kV transmission line are studied. Under low temperature condition, the coverage of the ice results in the disconnection between the aluminum tube and the steel anchor of strain clamp. Using macroscopic analysis, structure stress analysis, force analysis and mechanical property test, the fractured strain clamps are investigated. The crimping of the aluminum tube on the polished rod not on the grooves of the steel anchor leads to the damage of the strain clamps, which is defined as improper crimping. When improper crimping emerges, there will be only friction force between the aluminum tube and the steel anchor without shear force, and the tension of the conductor will be mainly supported by the steel strands which should be supported by both the aluminum tube and steel stands. Therefore, the breaking force of the strain clamp will greatly decrease. The failure analysis helps to promote the proper hydraulic crimping process and the safe operation of the transmission line. 展开更多
关键词 Transmission Line STRAIN clamp HYDRAULIC CRIMPING Process
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Numerical simulation of horizontal transversal displacement under different fixed clamping force of welding fixture for superalloy during TIG welding 被引量:3
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作者 Zhang Wenyang Guo Shaoqing +2 位作者 Yuan Zhongjin Tang Siyi Liang Jiayu 《China Welding》 EI CAS 2018年第2期19-23,共5页
A numerical model is established by Abaqus software for superalloy during tungsten inert gas (TIG) welding with welding fixture to simulate the weld temperature filed, stress and strain field, and weld plate's hori... A numerical model is established by Abaqus software for superalloy during tungsten inert gas (TIG) welding with welding fixture to simulate the weld temperature filed, stress and strain field, and weld plate's horizontal trasnsveral shift. The clamp force perpendicular to the weld plate varying with welding time was analyzed. The maximum clamp force during welding process was calculated. Under the condition of insufficient of clamping force, a half or one third of the maximum clamp force for example, the weld plate's horizontal transversal displacement could happen and also be computed. 展开更多
关键词 TIC welding welding fixture clamping force transverse displacement finite element method
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Minimum Normal Force Principle Based Quantitive Optimization of Clamping Forces for Thin Walled Part 被引量:2
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作者 张发平 孙厚芳 SHAHIDI.Butt 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期148-152,共5页
Based on the stability criteria of workpiece-fixture system, quantitative optimization of clamping forces during precise machining process for thin walled part is studied considering the contact condition between wokp... Based on the stability criteria of workpiece-fixture system, quantitative optimization of clamping forces during precise machining process for thin walled part is studied considering the contact condition between wokpiece and locator, the contact mechanical model is achieved, which is further been used to calculate the entire passive forces acting on the statically undetermined workpiece by means of the force screw theory as well as minimum norm force principle. Furthermore, a new methodology to optimize clamping forces is put forward, on the criteria of keeping the stability of workpiece during cutting process. By this way, the intensity of clamping forces is decreased dramatically, which will be most beneficial for improving the machining quality of thin-walled parts. Finally, a case study is used to support and validate the proposed model. 展开更多
关键词 workpiece-fixture system stability minimum norm force principle clamping forces optimization
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Tepid antegrade intermittent blood cardioplegia as an alternative for intermittent crossclamping with Lidoflazine 被引量:3
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作者 Sofia Kalantary Anouk de Bruyn +1 位作者 Steven Laga Inez Rodrigus 《World Journal of Cardiovascular Diseases》 2013年第7期454-457,共4页
Background: Blood cardioplegia is a technique with many variations in its use. Intermittent cross clamping with Lidoflazine has proven to deliver good cardioprotection in our center. Question: Is tepid (32°C) ant... Background: Blood cardioplegia is a technique with many variations in its use. Intermittent cross clamping with Lidoflazine has proven to deliver good cardioprotection in our center. Question: Is tepid (32°C) antegrade intermittent blood cardioplegia an efficient, safe and easy-to-use alternative to intermittent cross-clamping with Lidoflazine in elective isolated CABG in low-risk patients? Primary outcomes are heart enzymes (cTnI, CK-MB). Secondary outcomes are operation times, length of hospital stay, major complications and in-hospital mortality. Methods: From January 2012 until November 2012, 40 patients with LVEF ≥50%, EuroSCORE 展开更多
关键词 BLOOD CARDIOPLEGIA INTERMITTENT Cross clampING Lidoflazine MYOCARDIAL Protection
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STRENGTH ANALYSIS OF CLAMPING IN MICRO/NANO SCALE EXPERIMENTS 被引量:2
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作者 Liang Liu Dujuan Zeng +2 位作者 Xianlong Wei Qing Chen Xide Li 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第6期584-592,共9页
Two kinds of clamping in micro/nano scale experiments are investigated in this paper, one based on electron-beam-induced deposition, and the other on the van der Waals interaction. The clamping strength and mechanism ... Two kinds of clamping in micro/nano scale experiments are investigated in this paper, one based on electron-beam-induced deposition, and the other on the van der Waals interaction. The clamping strength and mechanism are analyzed both theoretically and experimentally. The influence of relative humidity on the micro/nano clamping and the method of electrostatic clamping are discussed. The clamping strength and performance of different clamping methods are compared considering the size and material of the clamped objects, and the application environments. 展开更多
关键词 micro/nano experimental mechanics clampING interracial strength electron-beaminduced deposition (EBID) cohesive zone model
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In vivo patch clamp recording technique in the study of neurophysiology 被引量:1
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作者 Lan-Wei CUI Yu-Rong LI 《Neuroscience Bulletin》 SCIE CAS CSCD 2006年第1期68-71,共4页
The patch clamp recording technique in vivois a blind patch clamp recording methods to record the current of the spinal or cereral neurons of anaes:hesia ( or awake) animals. This technique can be used to study the... The patch clamp recording technique in vivois a blind patch clamp recording methods to record the current of the spinal or cereral neurons of anaes:hesia ( or awake) animals. This technique can be used to study the synaptic function and plasticity in central nervous system in vivoin order to understand the physiological properties of the ion channels from an integrated point of view. The advantage of this technique have already presented itself in the study of the synaptic transmission and nervous network. Nowadays, in vivo patch whole-cell recording technique in combination with other techniques is becoming a common method in the research fields. 展开更多
关键词 patch clamp recording technique in vivo PHYSIOLOGY
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A patch-clamp study on human sperm Cl^- channel reassembled into giant liposome 被引量:1
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作者 Jun-Ping BAI Yu-Liang SHI Key Laboratory of Neurobiology,Intitute of Physiology,Shanghai Institutes for Biological Sciences,Chinese Academy of Science, Shanghai 200031,China 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第3期185-191,共7页
Aim: To record the single-channel currents and characterize the electrophysiological properties of the Cl^- channels inhuman sperm membrane. Methods: The membrane proteins extracted from the human sperm were reassembl... Aim: To record the single-channel currents and characterize the electrophysiological properties of the Cl^- channels inhuman sperm membrane. Methods: The membrane proteins extracted from the human sperm were reassembled intoliposome bilayer, and the liposomes were fused into giant liposomes with a diameter more than 10μm by dehydration-rehydration procedure. The giant liposomes were used to study the Cl^- channel activities by patch-clamp technique.Results: By patch clamping the giant liposome in an asymmetric NMDG (N-methyl-D-glucamine)-Cl (bath 100//pipette 200 mmol/L) solution system, three kinds of single-channel events with unit conductances of (74.1 ± 8.3) pS,(117.0±5.7) pS and (144.7±4.5) pS, respectively, were detected. Their activities were voltage-dependent and allwere blocked by SITS (4-acetamido-4'-isothiocyanato-stilbene-2', 2'-disulfonic acid) in a concentration-dependentmanner. By constructing the open and close dwell time distribution histograms and then fitting them with exponentialfunction, two time constants were obtained in both the open and the close states. The burst activity and conductancesubstate of the channels were observed. Conclusion; There exist three kinds of Cl^- channels with different conduc-tance in human sperm membrane at least. (Asian J Androl 2001 Sep; 3: 185 - 191) 展开更多
关键词 Cl^-channel giant liposome patch clamp human sperm membrane ion channel reassembly
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Floating Clamping Mechanism of PT Fuel Injector and Its Dynamic Characteristics Analysis 被引量:1
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作者 WANG Xinqing LIANG Sheng +2 位作者 XIA Tian WANG Dong QIAN Shuhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期550-556,共7页
PT fuel injector is one of the most important parts of modern diesel engine.To satisfy the requirements of the rapid and accurate test of PT fuel injector,the self-adaptive floating clamping mechanism was developed an... PT fuel injector is one of the most important parts of modern diesel engine.To satisfy the requirements of the rapid and accurate test of PT fuel injector,the self-adaptive floating clamping mechanism was developed and used in the relevant bench.Its dynamic characteristics directly influence the test efficiency and accuracy.However,due to its special structure and complex oil pressure signal,related documents for evaluating dynamic characteristics of this mechanism are lack and some dynamic characteristics of this mechanism can't be extracted and recognized effectively by traditional methods.Aiming at the problem above-mentioned,a new method based on Hilbert-Huang transform(HHT) is presented.Firstly,combining with the actual working process,the dynamic liquid pressure signal of the mechanism is acquired.By analyzing the pressure fluctuation during the whole working process in time domain,oil leakage and hydraulic shock in the clamping chamber are discovered.Secondly,owing to the nonlinearity and nonstationarity of pressure signal,empirical mode decomposition is used,and the signal is decomposed and reconstructed into forced vibration,free vibration and noise.By analyzing forced vibration in the time domain,machining error and installation error of cam are revealed.Finally,free vibration component is analyzed in time-frequency domain with HHT,the traits of free vibration in the time-frequency domain are revealed.Compared with traditional methods,Hilbert spectrum has higher time-frequency resolutions and higher credibility.The improved mechanism based on the above analyses can guarantee the test accuracy of injector injection.This new method based on the analyses of the pressure signal and combined with HHT can provide scientific basis for evaluation,design improvement of the mechanism,and give references for dynamic characteristics analysis of the hydraulic system in the interrelated fields. 展开更多
关键词 PT fuel injector floating clamping mechanism dynamic characteristics analysis Hilbert-Huang transform
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