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journal of Sport and Health Science 2022年第1期11卷 30-39页

作者： Barbara Pellegrini Chiara Zoppirolli Federico Stella Lorenzo Bortolan hans-Christer Holmberg Federico Schena CeRiSM(Research Centre of Mountain Sport and Health) University of VeronaRovereto 38068Italy Department of Neuroscience Biomedicine and MovementUniversity of VeronaVerona 37129Italy Swedish Winter Sports Research Centre Department of Health SciencesMid Sweden UniversityÖstersund 83125Sweden School of Kinesiology University of British ColumbiaVancouver BC V6T 1Z1Canada Biomechanics Laboratory Beijing Sport UniversityBeijing 100084China

Purpose:This study aimed to compare biomechanical aspects of a novel"running"diagonal stride(DSRUN)with"conventional"diagonal stride(DSCONV)skiing techniques performed at high ***:Ten elite Italian male junior cross-country skiers skied on a treadmill at 10 km/h and at a 10°incline utilizing both variants of the diagonal stride *** 3-dimensional kinematics of the body,poles,and roller skis;the force exerted through the poles and foot plantar surfaces;and the angular motion of the leg joints were ***:Compared to DSCONV,DSRUN demonstrated shorter cycle times(1.05±0.05 s vs.0.75±0.03 s(mean±SD),pj/m/kg vs.0.10±0.02 j/m/kg,pjoint extension than DSCONV-Further investigations,preferably on snow,should reveal whether DSRUN results in higher acceleration and/or higher peak speed.

关键词： Classical skiing Kinetics Roller skiing

Tuning static drop friction

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液滴(英文) 2023年第1期2卷 56-63页

作者： Alexandre Laroche Abhinav Naga Chirag Hinduja Azadeh Aghili Sharifi Alexander Saal Hyeonjin Kim Nan Gao Sanghyuk Wooh hans‐jürgen Butt Rüdiger Berger Doris Vollmer Physics at Interfaces Max Planck Institute for Polymer ResearchMainzGermany School of Chemical Engineering&Materials Science Chung‐Ang UniversitySeoulRepublic of Korea Department of Mechanical Engineering University of BirminghamBirminghamUK

The friction force opposing the onset of motion of a drop on a solid surface is typically considered to be a material property for a fixed drop volume on a given ***,here we show that even for a fixed drop volume,the static friction force can be tuned by over 30%by preshaping the *** static friction usually exceeds the kinetic friction that the drop experiences when moving in a steady *** forces converge when the drop is prestretched in the direction of motion or when the drop shows low contact angle *** contrast to static friction,kinetic friction is independent of preshaping the drop,that is,the drop *** friction forces reflect the material properties.

关键词： friction properties forces

A SQUID Bootstrap Circuit with a Large Parameter Tolerance

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Chinese Physics Letters 2013年第1期30卷 219-222页

作者： ZHANG Guo-Feng ZHANG Yi hans-joachim Krause KONG Xiang-Yan Andreas Offenhäusser XIE Xiao-Ming State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences(CAS)Shanghai 200050 Peter Grünberg Institute(PGI-8) Forschungszentrum Jülich(FZJ)D-52425JülichGermany joint Research Laboratory on Superconductivity and Bioelectronics Collaboration between CAS-Shanghai&FZJShanghai 200050

The voltage biased(SQUID)bootstrap circuit(SBC)was recently introduced as an effective means to reduce the preamplifier noise *** analyze the tolerances of the SBC noise suppression performance to spreads in SQUID and SBC circuit *** is found that the tolerance to spread mainly caused by the integrated circuit fabrication process could be extended by a one-time adjustable current feedback.A helium-cooled niobium SQUID with a loop inductance of 350 pH is employed to experimentally verify the *** this work,design criteria for fully integrated SBC devices with a high yield can be derived.

关键词： SQUID Bootstrap spread

高压扭转大塑性变形Al–Mg合金中的晶界结构

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材料研究学报 2014年第5期28卷 371-379页

作者：蒋婷慧刘满平谢学锋王俊吴振杰刘强 hans j.Roven 江苏大学材料科学与工程学院江苏省高端结构材料重点实验室镇江212013 挪威科技大学(NTNU)材料科学与工程学院

利用透射电镜和高分辨透射电镜(HRTEM)研究了高压扭转大塑性变形纳米结构Al–Mg合金中的位错和晶界结构。结果表明:对尺寸小于100 nm的晶粒,晶内无位错,其晶界清晰平直;而尺寸大于200 nm的大晶粒通常由几个亚晶或位错胞结构组成,局部位... 详细信息

利用透射电镜和高分辨透射电镜(HRTEM)研究了高压扭转大塑性变形纳米结构Al–Mg合金中的位错和晶界结构。结果表明:对尺寸小于100 nm的晶粒,晶内无位错,其晶界清晰平直;而尺寸大于200 nm的大晶粒通常由几个亚晶或位错胞结构组成,局部位错密度可高达1017m-2,这些位错往往以位错偶和位错环的形式出现。用HRTEM观察到了小角度及大角度非平衡晶界、小角度平衡晶界和大角度Σ9平衡晶界等不同的晶界结构。基于实验结果,分析了局部高密度位错、位错胞和非平衡晶界等在晶粒细化过程中的作用,提出了高压扭转Al–Mg合金的晶粒细化机制。

关键词：金属材料高压扭转大塑性变形铝合金晶界结构非平衡晶界位错

高压扭转大塑性变形Al-Mg铝合金中的层错和形变孪晶

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中国有色金属学报 2014年第6期24卷 1383-1392页

作者：刘满平王俊蒋婷慧吴振杰谢学锋刘强 hans j. ROVEN 江苏大学材料科学与工程学院江苏省高端结构材料重点实验室镇江212013 Department of Materials Scienceand Engineering Norwegian University of Science and TechnologyTrondheim 7491Norway

利用高分辨透射电镜研究高压扭转大塑性变形纳米结构Al-Mg铝合金中的位错、层错和形变孪晶。结果表明:在纳米晶和超细晶内均存在高密度的层错和形变孪晶;形成层错的Shockley部分位错可分别由0°纯螺型位错和60°混合位错分解得到;纳米... 详细信息

利用高分辨透射电镜研究高压扭转大塑性变形纳米结构Al-Mg铝合金中的位错、层错和形变孪晶。结果表明:在纳米晶和超细晶内均存在高密度的层错和形变孪晶;形成层错的Shockley部分位错可分别由0°纯螺型位错和60°混合位错分解得到;纳米孪晶既可由晶内层错动态叠加而形成,也可由晶界向晶内不断发射部分位错而向晶内长大,从而分别实验证实了分子动力学模拟预测的均质和非均质形核长大的孪生机制;观察到了由4层层错动态叠加而形成的特殊纳米孪晶。此外,高分辨透射电镜观察表明:在不同滑移面上的层错相交时,形成层错而产生的拖曳部分位错相遇可反应生成压杆位错和Lomer-Cottrell位错锁。依据经典位错理论和晶界发射部分位错的机制,提出了描述超细晶面心立方金属和合金中层错和形变孪晶形核长大的新模型。

关键词：铝合金高压扭转形变孪晶层错位错

Software improvement for evaluation of laryngopharyngeal pH testing(Restech)——a comparison between Data View 3 and 4

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World journal of Gastrointestinal Surgery 2020年第5期12卷 236-246页

作者： Dolores Thea Müller Elena Schulte Benjamin Babic Laura Knepper Claudia Fuchs Wolfgang Schroder Christiane j Bruns jessica M Leers hans Friedrich Fuchs Department of General VisceralCancer and Transplant SurgeryUniversity of CologneKoln 50937Germany

BACKGROUND When gastroesophageal reflux contents reach above the upper esophageal sphincter,patients may,in addition to typical reflux symptoms,present with atypical,extraesophageal symptoms related to laryngopharyngeal reflux(LPR).Surgical treatment of LPR has shown to lead to 70%symptom improvement,however no gold standard for the diagnosis of LPR *** 2007,the Restech Dx-pH was released as a valid method to measure acid exposure above the upper esophageal ***,a new software update was introduced for analysis of measured pH data and calculation of composite *** effect of the changes applied to the new software version have not yet been *** To compare results generated by Data View 3 to the most recently released Data View *** All patients with gastroesophageal reflux disease symptoms were seen in a specialized surgical outpatient clinic for gastrointestinal function *** chart review was performed of all patients presenting with suspected gastroesophageal reflux disease and extraesophageal reflux symptoms,who underwent laryngopharyngeal pH monitoring using the Restech Dx-pH system(Respiratory Technology Corp.,Houston,TX,United States)and simultaneous esophageal pH *** View 3 and Data View 4 were used to evaluate Restech studies *** entries such as mealtimes,supine and upright periods,and symptoms were entered manually to ensure accuracy and precise conversion of data between both software *** t test was performed for statistical analysis of *** A total of 174 patients(63.8%female)met inclusion criteria,all suffering from extraesophageal reflux symptoms as well as typical gastroesophageal reflux disease *** RYAN score upright was 48.77 in Data View 3 compared to 22.17 in Data View 4,showing a significant difference(~aP=0.0001).Similar results were shown for supine period(mean RYAN Score Data View 35.29 vs 1.42 in Data View 4,~cP=0.0001).For upright pe

关键词： Gastroesophageal reflux disease Laryngopharyngeal reflux disease Esophageal pH testing Oropharyngeal pH testing Restech Dx pH DeMeester score RYAN Score

Finite element analysis of strain distribution in ZK60 Mg alloy during cyclic extrusion and compression

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Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1902-1906页

作者：林金保王渠东刘满平陈勇军 hans j.ROVEN 太原科技大学应用科学学院太原030024 上海交通大学轻合金精密成型国家工程研究中心上海200240 挪威科技大学材料科学与工程学院特隆赫敏7491挪威

Finite element method was used to study the strain distribution in ZK60 Mg alloy during multi-pass cyclic extrusion and compression （CEC）. In order to optimize the CEC processing, the effects of friction condition and die geometry on the distribution of total equivalent plastic strain were investigated. The results show that the strain distributions in the workpieces are inhomogeneous after CEC deformation. The strains of the both ends of the workpieces are lower than that of the center region. The process parameters have significant effects on the strain distribution. The friction between die and workpiece is detrimental to strain homogeneity, thus the friction should be decreased. In order to improve the strain homogeneity, a large corner radius and a low extrusion angle should be used.

关键词： cyclic extrusion and compression finite element method friction ZK60 magnesium alloy strain homogeneity

No evidence for increased cell entry or antibody evasion by Delta sublineage AY.4.2

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Cellular & Molecular Immunology 2022年第3期19卷 449-452页

作者： Prerna Arora Amy Kempf Inga Nehlmeier Luise Graichen Martin S.Winkler Martin Lier Sebastian Schulz hans-Martin jäck Stefan Pöhlmann Markus Hoffmann Infection Biology Unit German Primate CenterKellnerweg 437077GöttingenGermany Faculty of Biology and Psychology Georg-August-University GöttingenWilhelmsplatz 137073GöttingenGermany Department of Anesthesiology University of Göttingen Medical CenterGeorg-August University GöttingenRobert-Koch-Straße 4037075GöttingenGermany Division of Molecular Immunology Department of Internal Medicine 3Friedrich-Alexander University Erlangen-NürnbergGlückstraße 691054ErlangenGermany

Since the beginning of the COVID-19 pandemic,multiple SARS-CoV-2 variants have *** some variants spread only locally,others,referred to as variants of concern,disseminated globally and became drivers of the *** SARS-CoV-2 variants harbor mutations relative to the virus circulating early in the pandemic,and mutations in the viral spike(S)protein are considered of particular relevance since the S protein mediates host cell entry and constitutes the key target of the neutralizing antibody *** a consequence,mutations in the S protein may increase SARS-CoV-2 infectivity and enable its evasion of neutralizing ***,mutations in the S protein can modulate viral transmissibility and pathogenicity.

关键词： SARS-CoV-2 AY.4.2 Delta Host cell entry Antibody evasion

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不用扫描法的叠加速度分析

国外油气勘探 1995年第2期7卷 211-222页

作者： hans j.Tieman 马作彬石油地球物理勘探局物探地质研究院

叠加速度可直接由地震资料估算,而不依赖于多速度叠加和许多近代常规程序中包含的研究技术。估算步骤包括:(1)用零炮检距时间和速度的初始估计值对地震资料(一个给定的共中点道集时窗内)进行动校正(NMO);(2)对全部炮检距应用两个不同的... 详细信息

叠加速度可直接由地震资料估算,而不依赖于多速度叠加和许多近代常规程序中包含的研究技术。估算步骤包括:(1)用零炮检距时间和速度的初始估计值对地震资料(一个给定的共中点道集时窗内)进行动校正(NMO);(2)对全部炮检距应用两个不同的加权函数并相加求和获得两个叠加结果;(3)将两个叠加结果互相关;(4)将时移转换成速度和时间校正值。对上述过程迭代地进行直到收敛为止。这种方法称为ARAMVEL(美国专利号4813027),是通过交互连续速度分析技术最佳实现的。这种方法虽然简单,但是不论在经验研究或理论分析方面都已证明它所确定的速度精度比基于扫描的常规方法获得的速度精度高。该法收敛快,通常仅需一两次迭代。该法实用,因为最初仅需近似信息。实际资料研究结果证明,对于处理具有不可忽视的横向速度变化的地区资料,该法能经济地给出细致的速度控制,并能提供旅行时信息,以便精确地进行层速度和深度转换。

关键词：地震数据处理速度分析叠加速度迭代法

Grain refinement of magnesium alloys processed by severe plastic deformation

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Transactions of Nonferrous Metals Society of China 2014年第12期24卷 3747-3754页

作者：陈勇军王渠东林金保刘满平 jarle HjELEN hans j.ROVEN 上海交通大学轻合金精密成型国家工程研究中心上海200030 Department of Materials Science and Engineering Norwegian University of Science and Technology ERC for Revolutionizing Metallic Biomaterials North Carolina A&T State University 太原科技大学应用科学学院太原030024 江苏大学材料科学与工程学院镇江212013 Center for Advanced Materials Qatar University

Grain refinement of AZ31 Mg alloy during cyclic extrusion compression （CEC） at 225-400 ℃ was investigated quantitatively by electron backscattering diffraction （EBSD）. Results show that an ultrafine grained microstructure of AZ31 alloy is obtained only after 3 passes of CEC at 225 ℃. The mean misorientation and the fraction of high angle grain boundaries （HAGBs） increase gradually by lowering extrusion temperature. Only a small fraction of {101^-2} twinning is observed by EBSD in AZ31 Mg alloys after 3 passes of CEC. Schmid factors calculation shows that the most active slip system is pyramidal slip {101^-1}〈1120〉and basal slip {0001}〈1120〉 at 225-350 ℃ and 400 ℃, respectively. Direct evidences at subgrain boundaries support the occurrence of continuous dynamic recrystallization （CDRX） mechanism in grain refinement of AZ31 Mg alloy processed by CEC.

关键词： magnesium alloys grain refinement continuous dynamic recrystallization (CDRX) electron backscattering diffraction(EBSD) cyclic extrusion compression (CEC)