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Acta Metallurgica sinica(English Letters) 2008年第6期21卷 391-398页

作者： s.j. Yao L.X. du X.H. Liu G.d. Wang state Key Laboratory ofRolling and Automation Northeastern University Shenyang 110004 China

Three warm-rolled ferrite/pearlite microstructures were prepared by rolling at 500℃, and the austenitizing characteristics were discussed in conjunction with deformation during the heating stage. The results indicated that the final austenite grain size was sensitive to the deformation direction of the initial warm-rolled microstructure. The transient microstructure at a given temperature was the most important influencing factor on the austenitizing characteristic combined with deformation. Moreover, the hot-rolled mierostructure also had to be prepared in an optimal state because of its direct effect on the warm-rolled microstructure.

关键词： Warm-rolled ferrite/pearlite Austenite deformation Recrystallization

磁性Gd3+离子对Chevrel相超导体PbMo6s8的临界电流和输运性质的影响

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低温物理学报 1999年第6期21卷 409-412页

作者：郑东宁,林淑媛,倪泳明,d.P.Hampshire,赵忠贤中国科学院物理研究所超导国家重点实验室!北京100080 中国科学院物理研究所!北京100080 中国科学院物理研究所超导国家重点实验室!北京100080 departmentofPhysics Universityofdurham durhamdH13LE UK 中国科学院物理研究所超导国家重点实验室!北京100080

采用高温固态反应和均衡热压方法相结合，我们制备了一系列Ｇｄ掺杂的Ｃｈｅｖｒｅｌ相ＧｄｘＰｂ１－ｘＭｏ６Ｓ８超导样品．为了研究掺入的磁性Ｇｄ３＋离子对于磁通线的钉扎作用和对临界电流及其它性质的影响，我们系统地测... 详细信息

采用高温固态反应和均衡热压方法相结合，我们制备了一系列Ｇｄ掺杂的Ｃｈｅｖｒｅｌ相ＧｄｘＰｂ１－ｘＭｏ６Ｓ８超导样品．为了研究掺入的磁性Ｇｄ３＋离子对于磁通线的钉扎作用和对临界电流及其它性质的影响，我们系统地测量了样品的电阻率，热电势，比热和临界电流密度．同时，我们计算了磁性Ｇｄ３＋离子与磁通线之间的相互作用和这种作用可能导致的磁通钉扎及对临界电流的影响，并与实验结果进行了比较．结果显示除非Ｇｄ３＋离子的分布是非常不均匀的，Ｇｄ３＋离子所引起的钉扎是不重要的．另一方面，热电势和电阻率等输运性质及比热的结果显示由于Ｇｄ３＋取代了Ｐｂ２＋使载流子浓度降低了．载流子浓度的降低进而引起其它超导参数如热力学临界场Ｂｃ的变化，导致钉扎势的减小，最终降低了临界电流．

关键词：临界电流超导体 Chevrel Gd PbMo6s8 钉扎输运性质磁通离子磁性

some hydrodynamic aspects of 3-phase inverse fluidized bed

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China Particuology 2007年第5期5卷 351-356页

作者： Krishna s.V.s.R. Bandaru d.V.s. Murthy K. Krishnaiah department of Chemical Engineering Indian Institute of Technology Madras

Hydrodynamics of 3-phase inverse fluidized bed is studied experimentally using low density particles for different liquid and gas velocities. The hydrodynamic characteristics studied include pressure drop, minimum liquid and gas fluidization velocities and phase holdups. The minimum liquid fluidization velocity determined using the bed pressure gradient, decreases with increase in gas velocity. The axial profiles of phase holdups shows that the liquid holdup increases along the bed height, whereas the solid holdup decreases down the bed. However, the gas holdup is almost uniform in the bed.

关键词： Inverse fluidization Inverse fluidized bed Hydrodynamics Phase holdup Axial holdup

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小型船舶上的液化石油气用具—火灾事故调查

金属热处理 2007年第Z1期32卷 95-98页

作者： Richard j.Martin Feifei Zhang Brad A.McGoran William d.Chapman 毅博科技咨询公司洛杉矶办事处 smith Chapman&Campbell 律师事务所

在美国西北太平洋地区的一次野外垂钓活动中,一名游客在向导的渔船中由于爆燃而严重受伤。事故的调查表明,燃油供应商销售并在渔船中安装了非标准的液化石油气加热系统,该系使用的元件未达到液化石油气的使用标准。如果使用了正确的加... 详细信息

在美国西北太平洋地区的一次野外垂钓活动中,一名游客在向导的渔船中由于爆燃而严重受伤。事故的调查表明,燃油供应商销售并在渔船中安装了非标准的液化石油气加热系统,该系使用的元件未达到液化石油气的使用标准。如果使用了正确的加热系统,同时向导能够根据安全预防常识及时观察到易燃燃料的状况,那么这起事故是完全可以避免的。本文阐述了对此事故的调查,并希望提醒船只使用者和海洋专业人员能明白使用非标准燃油输运元件的内在危险性。

关键词：液化石油气火灾事故调查

FATIGUE LIVEs FOR INdUCTION HARdENEd sHAFTs MATERIALs ACCORdING TO THE ENVIRONMENTAL TEMPERATUREs

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Acta Metallurgica sinica(English Letters) 2005年第5期18卷 585-593页

作者： d.G. Lee K.C. jang j.M. Kuk I.s. Kim Korea Institute of Industrial Technology Gwangju 506-824 Korea dept. of Mechanical Engineering Mokpo National University Mokpo 534-729 Korea

Rotary bending fatigue tests were carried out with two kinds of materials, s43C and s50C, using the front engine and front drive shaft （FF shaft） of vehicle. The specimens were induction hardened about 1.0mm depth from the specimen surface, and the hardness value on the surface was about HRC56-60. The tested environment temperatures were -30, 25 and 80℃ in order to look over effect of the induction hardening and the environmental temperatures on the fatigue characteristics. The fatigue limit of induction hardened specimens increased more about 45% than non-hardened specimens showing that the endurances of s43C and s50C were 98.1 and 107.9MPa in non-hardened samples, 147.1 and 156.9MPa in hardened samplesrespectably. The maximum tensile and compressive stress on the small circular defect was about ＋250 and -450MPa respectively when circular defect is situated on top and bottom. The fatigue life increased 80, 25 and -30℃ in order regardless of hardening. In comparison of the fatigue lives on the basis of tested result at 25℃, the fatigue lives of non-hardened specimens decreased about 35%, but that of hardened specimens decreased about only 5% at 80℃ more than at 25℃. And fatigue life of non-hardened and hardened specimens were about 110% and 120% higher at -30℃ than that of 25℃. Based on the result of stress distribution near the defect, the tensile and compressive stress repeatedly generated by load direction were the largest on the small circular defect due to the stress concentration.

关键词： induction hardening fatigue test front engine and front drive shaft,fatigue crack fatigue life fatigue life ratio

活性siO_2在焊接熔渣-金属界面化学反应的热动力学分析

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焊接学报 2005年第10期26卷 43-46页

作者：李晓泉杨旭光方臣富江苏科技大学先进焊接技术省级重点实验室江苏镇江212003

针对焊接熔渣-金属冶金反应远离平衡的特性,从非平衡态热力学及液-液两相交互作用耦合的角度建立了液态熔渣组成中s iO2与熔敷金属间的化学反应热动力学模型。对建立的模型通过试验测试,并借助于M atlab工具软件进行了非线性数值求解。... 详细信息

针对焊接熔渣-金属冶金反应远离平衡的特性,从非平衡态热力学及液-液两相交互作用耦合的角度建立了液态熔渣组成中s iO2与熔敷金属间的化学反应热动力学模型。对建立的模型通过试验测试,并借助于M atlab工具软件进行了非线性数值求解。定量计算结果表明,焊接过程各区域的冶金反应方向及限度存在明显的不同,熔滴反应区正向氧化反应偏离平衡态的距离远大于熔池反应区逆向脱氧反应偏离平衡的距离。同时反应所处的温度及熔渣中s iO2含量都在一定程度上影响反应的方向及限度,从而对焊缝金属的增氧产生重要影响。

关键词：冶金反应熔滴反应区熔池反应区反应方向

dynamic buckling mechanism of pillar rockbursts induced by stress waves

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journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 944-953页

作者： j.deng N.s.Kanwar M.d.Pandey W.-C.Xie department of Civil Engineering Lakehead UniversityThunder BayOntarioP7B 5E1Canada Centre of Excellence for sustainable Mining and Exploration Lakehead UniversityThunder BayOntarioP7B 5E1Canada department of Civil and Environmental Engineering University of WaterlooWaterlooOntarioN2L 3G1Canada

Rockbursts are sudden and violent rock failures that can lead to huge production and equipment losses,injury or death of mining *** has been regarded as one of the key mechanisms of rockbursts,which are often induced by dynamic loads from mining excavations,such as drilling and blasting in underground *** paper attempts to investigate the dynamic buckling mechanism of pillar rockbursts in underground mining,by considering rockbursts as a dynamic stability problem of underground rock *** results include:(1)A new explanation of the“sudden and violent”phenomenon of rockbursts,characterized by exponential growth of the amplitudes of transverse displacement responses,even in the presence of rock damping;(2)Identification of the critical role in inducing rockbursts of dynamic loads that bear frequencies approximately double the natural pillar frequency;(3)The greater influence on rockburst occurrence of the amplitude of dynamic component relative to the static component of loads;and(4)Quantification of the relative effects of stress waveform of dynamic loads on pillar rockbursts,which are in decreasing order if other parameters remain constant:rectangular,sinusoidal,and exponential *** examples are provided and limitations of the approach are *** research is motivated by the on-going and ubiquitous occurrence of rockbursts in underground excavations all around the *** contrast to conventional methods that use rock specimens or rock materials to study rockbursts,this investigation emphasizes the structural effects on rockbursts,which has potential applications in hard rock mining engineering.

关键词： Pillar rockbursts Buckling mechanism stress waves structural rock mechanics

三种麻醉深度监测方法评价小儿腹部手术镇静效果

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现代医院 2010年第12期10卷 31-33页

作者：黎邝茂名农垦医院广东高州525200

目的探讨脑电双频指数(BIs)、听觉诱发电位指数(AEPI)及病人状态指数(PsI)在监测小儿腹部手术镇静效果的差异,以选取最佳监测方案。方法 75例患儿分为三组(各组n=25),均使用腰麻+硬膜外联合麻醉,术中辅助咪唑安定维持患儿睡眠,分别使用... 详细信息

目的探讨脑电双频指数(BIs)、听觉诱发电位指数(AEPI)及病人状态指数(PsI)在监测小儿腹部手术镇静效果的差异,以选取最佳监测方案。方法 75例患儿分为三组(各组n=25),均使用腰麻+硬膜外联合麻醉,术中辅助咪唑安定维持患儿睡眠,分别使用BIs、AEPI及PsI监测麻醉深度;比较三组在入室(T1)、切皮前60 s(T2)、切皮即刻(T3)、切皮后60 s(T4)及切皮后120 s(T5)进行监测评分;比较改良后OAA/s同一评分下的BIs、AEPI及PsI指数差异,并进行相关性分析。结果术中三组均无出现切皮体动,但患儿T2～T5四个时间点的BIs、AEPI及PsI指数的组间差异有显著性,且均以PsI最低(ps=0～3分所对应的BIs、AEPI及PsI指数有组间差异(psI最低;相关性分析表明上述3个指数与OAA/s评分呈正相关性,且以PsI与OAA/s的相关性最强(r=0.793,p=0.016)。结论 PsI受切皮的影响相对最小,且灵敏度、区分度较好,是监测小儿腹部全麻手术镇静效果较为理想的指标。

关键词：麻醉深度小儿腹部手术指数相关性分析

维普期刊数据库博看期刊

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用傅里叶分析法研究艾里光束远场传播特性

光子学报 2017年第3期46卷 88-99页

作者：吴云龙聂劲松邵立孙晓泉电子工程学院脉冲功率激光技术国家重点实验室合肥230037

为了从理论上深入分析新型无衍射光束艾里光束在有限能量条件下的远场传播特性,首先,从决定光波在自由空间传播的一维旁轴波动方程入手,采用傅里叶分析法,结合艾里函数的特殊性质,并利用经过指数衰减的有限能量初始条件,完整给出了有限... 详细信息

为了从理论上深入分析新型无衍射光束艾里光束在有限能量条件下的远场传播特性,首先,从决定光波在自由空间传播的一维旁轴波动方程入手,采用傅里叶分析法,结合艾里函数的特殊性质,并利用经过指数衰减的有限能量初始条件,完整给出了有限能量条件下用于精确描述一维艾里光束在自由空间传播特性的波动方程解析解.然后,利用所得到解析解分别对一维和二维艾里光束在自由空间的传播特性进行了研究,重点分析了不同参量条件对艾里光束进行无衍射传播和横向自加速的影响.研究表明:当任意横向尺度为100μm,衰减系数为0.03、0.05、0.07、0.1、0.2时,二维艾里光束无衍射传播距离分别为1 014、624、455、338、193mm;当横向尺度保持不变时,衰减系数越小,艾里光束保持无衍射传播的距离越大;当衰减系数保持不变时,横向尺度越小,艾里光束横向自加速越大.所采用的研究方法也可用于研究艾里光束在介质中的传播特性.

关键词：艾里光束传播特性傅里叶分析旁轴波动方程解析解

Modeling Alzheimer's disease:considerations for a better translational and replicable mouse model

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Neural Regeneration Research 2022年第11期17卷 2448-2449页

作者： joshua d.Cho Mu Yang Ismael santa-Maria Taub Institute for Research on Alzheimer's disease and the Aging Brain Department of Pathology&Cell BiologyColumbia University The Mouse NeuroBehavior Core.Institute for Genomic Medicine Columbia University

Alzheimer's disease (Ad) mouse models have proven to be an invaluable tool for deepening our understanding of disease mechanisms and for developing ***,one common frustration is the lack of replicability in behavioral *** we have discussed in our recent publication (Cho et al.,2021),in the htau mouse model,the cognitive impairment reported in the original study has not been consistently replicated by different labs over the past *** variability in behavioral findings seems to exist in many,if not all,Ad mouse models that have been behaviorally evaluated.

关键词： Alzheimer tau