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电子显微学报 1997年第4期 183-184页

作者： Marun J.Abbudi \ l.y.Pang\ David M.Barnett (Division of Applied Mechanics, Department of Mechanical Engineering, Stanford University, Stanford, CA 94305 4040, USA)

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关键词： Stress Fields Determination

Effects of cyclic loading on temperature evolution of UlTIMET superalloy: experiment and theoretical modeling

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中国有色金属学会会刊：英文版 2002年第4期12卷 734-747页

作者： l.Jiang H.Wang 等 DepartmentofMateriaisScienceandEngineering UniversityofTennesseeKnoxvilleTN37996USA MetalsandCeramicsDivision OakRidgNationalLaboratoryOakRidgeTN37831USA

High speed, high resolution infrared thermography, as a non contact, full field, and nondestructive technique, was used to study the temperature variations of a cobalt based UlTIMET alloy subjected to cyclic fatigue. During each fatigue cycle, the temperature oscillations, which were due to the thermal elastic plastic effects, were observed and related to stress-strain ana.yses. The change of temperature during fatigue was utilized to reveal the accumulation of fatigue damage. A constitutive model was developed for predicting the thermal and mechanical responses of UlTIMET alloy subjected to cyclic deformation. The model was constructed in light of internal state variables, which were developed to characterize the inelastic strain of the material during cyclic loading. The predicted stress-strain and temperature responses were found to be in good agreement with the experimental results.

关键词：超级合金热分析疲劳 UlTIMET 理论模型

Experimental verification of the scaling relationships for bubbling gas-fluidised beds using the PEPT technique

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Experimental verification of the scaling relationships for b...

low-frequency Oscillation Damping Control for large-scale Power System with Simplified Virtual Synchronous Machine

CCAST“颗粒物理”研讨会

作者： M.Stein y.l.Ding J.P.K.Seville School of Chemical Engineering University of Birmingham Edgbaston. Birmingham B15 2TT UK School of Chemical Engineering University of Birmingham Edgbaston. Birmingham B15 2TT UK School of Chemical Engineering University of Birmingham Edgbaston. Birmingham B15 2TT UK

＜正＞ An experimental verification of the scaling relationships for bubbling gas-fluidised beds has been carried out by measuring particle cycle frequency. The Positron Emission Particle Tracking technique was used, which enabled non-intrusive measurements of solids motion in three dimensions with a spatial resolution of -2 mm under the conditions of this work. Three cylindrical beds （70, 141 and 240 mm ID） equipped with multiple orifice-type distributors were tested. It was shown that for geometrically similar beds, the pair of Froude numbers based on the minimum fluidisation and excess gas velocities was sufficient for similarity at the viscous limit. The experimental results showed little influence of the gas-to-particle density ratio, but a small effect of particle-to-bed diameter ratio when the change in the ratio was significant. The experimental results also indicated a possible relaxation of the viscous limit up to a particle Reynolds number of about 100. More experimental studies are needed to confirm the validity of such a relaxation. 2002 Elsevier Science ltd. All rights reserved.

关键词： Bubbling gas-fluidised beds Scaling relationships Solids motion Experimental validation Viscous limit PEPT

来源： cnki会议评论

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1424-1435页

作者： Karim Sebaa.yang Zhou yong li Ayetül Gelen Hassan Nouri Advanced Electronics Systems laboratory University of Medea Institute of Energy Systems Energy Efficiency and Energy EconomicsTU Dortmund University IEEE College of Electrical and Information Engineering Hunan University Department of Electrical Electronic Engineering Bursa Technical University Power Systems and Energy Research laboratory University of the West of England

This study focuses on a virtual synchronous machine(VSM) based on voltage source converters to mimic the behavior of synchronous machines(SMs) and improve the damping ratio of the power system. The VSM model is simplified according to some assumptions(neglecting the speed variation and the stator transients) to allow for the possibility of dealing with low-frequency oscillation in large-scale systems with ma.y VSMs. Furthermore, a virtual power system stabilizer(VPSS) structure is proposed and tuned using a method based on a linearized power system dynamic model. The linear and nonlinear ana.yses examine the stability of two modified versions of a 16-machine power system in which, in the first case, partial classical machines are replaced by VSMs, and in the second case, all SMs are replaced by VSMs. The simulation results of the case studies validate the efficiency of the proposed control strategy.

关键词： Synchronous machine(SM) small-signal stability transient stability virtual power system stabilizer(VPSS) virtual synchronous machine(VSM)

Flow and magnetic structures in a kinematic ABC-dynamo

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 95-100页

作者： Tao Zhang Zhiliang lin Chenyang Huang Alistair G.l.Borthwick State Key laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China School of Engineering The University of EdinburghEdinburgh EH93JLUK

Dynamo theory describes the magnetic field induced by the rotating,convecting and electrically conducting fluid in a celestial *** classical ABC-flow model represents fast dynamo action,required to sustain such a magnetic *** this letter,lagrangian coherent structures(lCSs)in the ABC-flow are detected through Finite-time lyapunov exponents(FTlE).The flow skeleton is identified by extracting intersections between repelling and attracting *** the case A=B=C=1,the skeleton structures are made up from lines connecting two different types of stagnation points in the *** corresponding kinematic ABC-dynamo problem is solved using a spectral method,and the distribution of cigar-like magnetic structures *** links are found to exist between lCSs in the ABC-flow and induced magnetic structures,which provides insight into the mechanism behind the ABC-dynamo.

关键词： kinematic dynamo theory ABC-flow lagrangian coherent structure

一项氢吗啡酮和吗啡鞘内镇痛用于难治性癌痛的多中心、单盲、平行对照、非劣效临床研究

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中华医学杂志 2021年第43期101卷 3541-3541页

作者： Ma K Jin y Wang l 纪运(编译) 不详上海交通大学医学院附属新华医院疼痛科

氢吗啡酮可替代吗啡用于鞘内药物输注系统(IDDS)治疗难治性癌痛,然而,尚未有充分的临床证据来证明。此项研究纳入来自中国12个疼痛管理中心的233例患者,随机分为两组:鞘内输注氢吗啡酮组(ITHM,n=121)和鞘内输注吗啡组(ITMO,n=112)。主... 详细信息

氢吗啡酮可替代吗啡用于鞘内药物输注系统(IDDS)治疗难治性癌痛,然而,尚未有充分的临床证据来证明。此项研究纳入来自中国12个疼痛管理中心的233例患者,随机分为两组:鞘内输注氢吗啡酮组(ITHM,n=121)和鞘内输注吗啡组(ITMO,n=112)。主要观察指标为临床成功率,定义为患者疼痛缓解≥50%的比率。非劣效性界值(NIm)为15%。次要观察指标包括每日疼痛视觉模拟评分(VAS)、爆发痛(BTP)发生率、鞘内药物剂量、患者静脉自控镇痛(PCA)按压次数、焦虑抑郁状态(患者健康问卷抑郁量表PHQ-9、广泛性焦虑量表GAD-7)。

关键词：氢吗啡酮观察指标临床证据焦虑抑郁状态难治性癌痛按压次数平行对照单盲

THE lIQUID MATRIX EFFECTS FOR DETERMINATION OF OlIGOSACCHARIDES By lSIMS

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Chinese Science Bulletin 1992年第17期37卷 1431-1435页

作者：蒋可 A.l.BURlINGAME Research Center for Eco-Environmental Sciences Academia Sinica Beijing 100085 PRC University of California San Francisco USA

Glycoconjugate, as a carrier of message, has important biological functions. The sugar moiety contains surprising information. Its molecular structure has been paid increasing attention to since the 1980’s. The appli... 详细信息

关键词： the structure of oligosaccharides liquid seconda.y ionization mass spectrometry(lSIMS) immunoglobulin M(IgM).

A Foundation for Developing Digital Preservation Policy： The InterPARES Policy Framework

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现代图书情报技术 2008年第1期 1-12页

作者： SHERRy l. XIE School of libra.y Archival and Information Studies University of British Columbia Canada

近年来,数字资源长期保存领域经历了从基础理论研究、个体实验,到最佳实践的发展过程。继2004年北京、2005年德国、2006年北美成功举办之后,2007年10月11-12日,数字资源长期保存国际会议(iPRES2007)再次回归北京,由国家科技图书文献中... 详细信息

近年来,数字资源长期保存领域经历了从基础理论研究、个体实验,到最佳实践的发展过程。继2004年北京、2005年德国、2006年北美成功举办之后,2007年10月11-12日,数字资源长期保存国际会议(iPRES2007)再次回归北京,由国家科技图书文献中心主办,中国科学院国家科学图书馆组织承办。本次会议主题为"数字资源长期保存:项目进展和最佳实践",结合具体项目和实践经验,分别从数字资源长期保存的战略计划与基础设施、相关管理问题、技术研究与实践、认证与评估、教育与培训5个方面进行了介绍,并就面临的问题和下一步发展进行了交流。《现代图书情报技术》杂志作为此次会议协办媒体,组织部分参会论文形成专辑发表,集中反映国内外数字资源长期保存领域重大项目的研究进展以及实施路线,供广大研究人员参考、借鉴。

关键词：数字资源长期保存国际会议政策框架图书馆 2007年北京

Changes in free amino acids and polyamine levels in Satsuma leaves in response to Asian citrus psyllid infestation and water stress

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Insect Science 2014年第6期21卷 707-716页

作者： Nasir S. A. Malik Jose l. Perez Madhurababu Kunta Joseph M. Patt Robert l. Mangan USDA-ARS ERRC 600 E Mermaid lane Wyndmoor PA 19038-8598 USDA-ARS SPARC 2881 F&B Road College Station TX 77845 Texas A&M University-Kingsville Citrus Center 312 North International Blvd Weslaeo TX 78596 U. S. Horticultural Research laboratory 2001 South Rock Road Fort Pierce FL 34945 Subtropical Horticultural Research Station 13601 Old Coulter Road Miami FL 33158 USDA-ARS 2413 E. Hwy 83 Weslaco TX 78596 USA

The effects of biotic and abiotic stresses on changes in amino acids and polyamine levels in Satsuma orange （Citrus unshiu; cultivar Owari） leaves were inves- tigated. Asian citrus psyllids Diaphorina citri （Kuwayama）（ACP） infestation was used to induce biotic stress while a water deficit was imposed to induce abiotic stress. Potted trees were infested by placing 50 psyllids on 3 citrus leaves enclosed in nylon mesh bags for 5 d. A parallel set of plants were kept water stressed by maintaining the soil at 20% water holding capacity for 5 d. levels of total free amino acids were higher in water stressed and ACP infested leaves. Polyamine putrescine increased in infested leaves but not in water stressed leaves. Proline was the most abundant amino acid and its levels significantly increased by both biotic and abiotic stresses. Proline levels in infested leaves were significantly higher than the water stressed leaves. Histidine, methionine, asparagine, arginine, serine, and leucine levels also increased significantly in infested leaves, but in water stressed leaves only leucine, methionine, and threonine increased. levels of amino acids, such as tyrosine, isoleucine, phenylalanine, glutamic acid, and alanine, declined in infested leaves. Under water stress asparagine, phenylalanine, serine, and histidine also declined compared to controls. This indicates that while proteolysis occurred under both stresses, metabolic conversion of amino acids was different under the two stresses. In ACP infested leaves some amino acids may be used as feeding material and/or converted into seconda.y metabolites for defense.

关键词： amino acids citrus Diaphorina citri polyamines