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Photoelectrochemical characteristics of AB5-type hydrogen storage alloy modified with ZnO-TiO2 photocatalyst

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Photoelectrochemical characteristics of AB5-type hydrogen st...

基于mR弹性成像的定量硬度在肝细胞癌微血管浸润分级评估中的价值

第九届全国氢能学术会议

作者： Y.G Tang,m.s.li,s.F.Zhang,Z.H.su Central south University,China

Composite compounds of ZnO and TiO powders were prepared by using zinc acetate, tetrabutyl titanate,urea and ammonia via hydrolysis-precipitation ***5-type hydrogen storage alloy(HsA) elect rodes modified with ZnO-TiO2 powders were prepared and the photoelectrochemical characteristics of the as-prepared electrodes were *** results of AC impedance show that ZnO-TiO2 nanopaticles absorb the photon of the UV light

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国际医学放射学杂志 2023年第4期 494-495页

作者： L.N.Zhang m.s.li J.Zhu Y.Zhang Y.Q.Xiao 杨茜

摘要目的评价基于mR弹性成像（mRE）的定量硬度对无创预测肝细胞癌（HCC）微血管浸润（mVI）分级的潜在应用价值。方法回顾性纳入185例经组织病理学证实的HCC

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多频mR弹力断层成像检测前列腺癌:与多参数mRI的比较

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国际医学放射学杂志 2021年第4期44卷 477-478页

作者： m.s.li J.Guo P.Hu H.C.Jiang J.Chen J.Hu 高珍

摘要多参数 mRI 用于检测前列腺癌(PCa),但未考虑癌对前列腺组织的机械改变。目的探讨多频 mR 断层弹力成像刚度和变移性量化值检出 PCa 的效能,并与采用前列腺成像

关键词：前列腺癌断层成像 mRI

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改进半透镜半姆欧型继电器特性的研究

河北电力技术 1986年第3期 49-56页

作者： m.s.li T.C.Cheng C.Y.Wu 赵自刚

多年来,姆欧型方向阻抗继电器已广泛应用于高压和特高压系统.但其在某些故障条件下的误动一直是一个需要解决的主要问题.一种情况是发生出口带接地电阻短路时,安装在非故障相的姆欧继电器将误动作.另一种情况是发生带接地电阻的反方向... 详细信息

多年来,姆欧型方向阻抗继电器已广泛应用于高压和特高压系统.但其在某些故障条件下的误动一直是一个需要解决的主要问题.一种情况是发生出口带接地电阻短路时,安装在非故障相的姆欧继电器将误动作.另一种情况是发生带接地电阻的反方向故障时姆欧继电器的误动.理论分析和数字计算表明,在这些偶然情况下,由距离继电器所看到的阻抗在第二象限进入继电器动作区.为改善保护的特性,有必要限制或缩小其在第二象限的动作区.在R-X平面上具有半透镜半姆欧特性的方向阻抗继电器能满足上述要求.本文详细分析了具有透镜或透镜一姆欧特性的各种方向阻抗继电器的原理.提出了一种构成成透镜一姆欧继电器的实用方法.为评价透镜一姆欧继电器的特性,在不同条件下进行了一系列试验研究.还进行了计算机模拟和电力系统模型试验.结果表明,透镜一姆欧继电器的特性与理论分析相当吻合,证明该继电器更适用于大容量、重负荷、长距离特高压的输电线路.在用于500KV电力系统中的JGBJ—500距离保护上采用了这种透镜一姆欧继电器.

关键词：继电器动作特性故障相特高压系统第二象限电子元件电器特性透镜电压矢量

Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： Jinbang li Ningning ZHOU Janet s.s.WONG school of mechanical Engineering and mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Dedicated siPm array for GRD of GECAm

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Radiation Detection Technology and methods 2022年第1期6卷 63-69页

作者： D.L.Zhang X.L.sun Z.H.An X.Q.li X.Y.Wen K.Gong C.Cai Z.Chang G.Chen C.Chen Y.Y.Du m.Gao R.Gao D.Y.Guo J.J.He D.J.Hou Y.G.li C.Y.li G.li L.li X.F.li m.s.li X.H.liang X.J.liu Y.Q.liu F.J.Lu H.Lu B.meng W.X.Peng F.shi H.Wang J.Z.Wang Y.s.Wang H.Z.Wang X.Wen s.Xiao s.L.Xiong Y.B.Xu Y.P.Xu s.Yang1 X.Zhou J.W.Yang Fan Zhang s.N.Zhang C.Y.Zhang C.m.Zhang Fei Zhang X.Y.Zhao Institute of High Energy Physics CASBeijing 100049China state Key Laboratory of Particle Detection and Electronics Beijing 100049China

Purpose The discovery of gravitational waves and gamma-ray bursts heralds the era of multi-messenger *** the adoption of two small satellites to achieve the all-sky monitoring of gamma-ray bursts,the gravitational wave highenergy electromagnetic counterpart all-sky monitor(GECAm)possesses a quasi-real-time early warning ability and plays an important role in positioning the sources of gravitational waves and in subsequent *** satellite of GECAm was fitted with 253-inch-diameter gamma-ray detectors(GRD),covering an energy range of 8–2 *** have adopted silicon photomultiplier tubes(siPm)in lieu of photomultiplier tubes(PmT)to adapt to the dimensional limitations of *** A unique 3-inch circular siPm array was *** this design,646×6 mm chips were arranged evenly in a circular manner with the seams filled with reflecting films,thus achieving satisfactory uniformity of light *** integrated pre-amplifier circuit on the back of the siPm array adopted two-level grouping and summing;further,it achieved a satisfactory signal-to-noise *** high-gain and low-gain channels were adopted to achieve a large dynamic range,and two independent power supply units were used,where each unit can be closed separately,thus improving *** Performance studies show that this siPm array meets the requirements of *** A 3-inch siPm array have been developed that uses grouped summation,reflective films,a circular arrangement,two groups of independent power supplies,high-and low-gain signals,differential signal output technologies,*** solution can be used not only for GECAm,but also as a general solution for siPm-based scintillation detectors.

关键词： siPm GECAm Gamma-ray signal-to-noise ratio Reflecting film Pre-amplifier

The design and performance of charged particle detector onboard the GECAm mission

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Radiation Detection Technology and methods 2022年第1期6卷 53-62页

作者： Y.B.Xu X.Q.li X.L.sun s.Yang H.Wang W.X.Peng X.H.liang K.Gong Y.Q.liu D.Y.Guo X.Y.Zhao C.Y.li Z.H.An J.J.He X.J.liu X.Y.Wen s.L.Xiong Fan Zhang D.L.Zhang C.Y.Zhang C.Cai Z.Chang G.Chen C.Chen Y.Y.Du m.Gao R.Gao D.J.Hou Y.G.li G.li L.li X.F.li m.s.li F.J.Lu H.Lu B.meng F.shi J.Z.Wang Y.s.Wang H.Z.Wang X.Wen s.Xiao Y.P.Xu J.W.Yang Q.B.Yi s.N.Zhang C.m.Zhang F.Zhang Y.Zhao X.Zhou Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Background The Gravitational wave highly energetic Electromagnetic Counterpart All-sky monitor(GECAm)is dedicated to detecting gravitational wave gamma-ray *** is capable of all-sky monitoring over and discovering gamma-ray bursts and new radiation *** consists of two microsatellites,each equipped with 8 charged particle detectors(CPDs)and 25 gamma-ray detectors(GRDs).Purpose The CPD is used to measure charged particles in the space environment,monitor energy and flow intensity changes,and identify between gamma-ray bursts and space charged particle events in conjunction with *** CPD uses plastic scintillator as the sensitive material for detection,silicon photomultiplier array as the optically readable device,and the inlaid Am-241 radioactive source as the onboard calibration *** In this paper,we will present the working principle,physical design,functional implementation and preliminary performance test results of the *** a result,the energy range of electron,gamma-ray detection efficiency and dead time are tested to be better than the indexes required through the ground calibration experiment.

关键词： GECAm CPD siPm

Quality assurance test and failure analysis of siPm arrays of GECAm satellites

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Radiation Detection Technology and methods 2022年第1期6卷 35-42页

作者： D.L.Zhang m.Gao X.L.sun X.Q.li Z.H.An X.Y.Wen C.Cai Z.Chang G.Chen C.Chen Y.Y.Du R.Gao K.Gong D.Y.Guo J.J.He D.J.Hou Y.G.li C.Y.li G.li L.li X.F.li m.s.li X.H.liang X.J.liu Y.Q.liu F.J.Lu H.Lu B.meng W.X.Peng F.shi H.Wang J.Z.Wang Y.s.Wang H.Z.Wang X.Wen s.Xiao s.L.Xiong Y.B.Xu Y.P.Xu s.Yang J.W.Yang Fan.Zhang s.N.Zhang C.Y.Zhang C.m.Zhang Fei Zhang X.Y.Zhao X.Zhou Institute of High Energy Physics CASBeijing 100049People’s Republic of China

Background The Gravitational wave high-energy Electromagnetic Counterpart All-sky monitor(GECAm)satellite developed a siPm-based gamma-ray detector to monitor the gravitational wave-related GRBs and guide subsequent observations in other wavelengths of *** As all the available siPm devices belong to commercial grade,quality assurance tests need to be performed in accordance with the aerospace *** In the siPm application of GECAm,quality assurance experiments were *** mechanism of the failure of siPm devices was analyzed during the development *** Based on the quality assurance test results,the fnal pass rate of siPm array was 95%.Based on the failure analysis,it was found that a piece of siPm had a leakage channel after longtime operation due to device *** According to the accumulated experience,in the reliability test of siPm,it is necessary to pay special attention to test the impedance of each pin of siPm to ground and confrm that the power switch state of siPm is controllable.

关键词： Gravitational waves Gamma-ray detectors silicon photomultipliers Quality assurance test Failure analysis

The data acquisition algorithm designed for the siPm-based detectors of GECAm satellite

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Radiation Detection Technology and methods 2022年第1期6卷 70-77页

作者： Y.Q.liu K.Gong X.Q.li X.Y.Wen Z.H.An C.Cai Z.Chang G.Chen C.Chen Y.Y.Du m.Gao R.Gao D.Y.Guo J.J.He D.J.Hou Y.G.li C.Y.li G.li L.li X.F.li m.s.li X.H.liang X.J.liu F.J.Lu H.Lu B.meng W.X.Peng F.shi X.L.sun H.Wang J.Z.Wang Y.s.Wang H.Z.Wang X.Wen s.Xiao s.L.Xiong Y.B.Xu Y.P.Xu s.Yang J.W.Yang Q.B.Yi Fan Zhang D.L.Zhang s.N.Zhang C.Y.Zhang C.m.Zhang Fei Zhang X.Y.Zhao Y.Zhao X.Zhou Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of sciences Chinese Academy of SciencesBeijing 100049China Physics and space science College China West Normal UniversityNanchong 637002China

Background The Gravitational Wave High-energy Electromagnetic Counterpart All-sky monitor(GECAm)consists of 2 microsatellites,each of which contains 25 GRD(LaBr3)detectors and 8 CPD(plastic scintillator)*** silicon photomultiplier(siPm)array is used to read each *** output signal of these detectors with siPm array is very special and challenging to *** this study,a novel data acquisition(DAQ)algorithm for these detectors is designed and implemented,and the content of the output event packet is *** and Conclusion The performances,including the event acquisition efficiency of this DAQ algorithm,are extensively verified through experimental *** the on-ground and in-flight tests,this algorithm has excellent performance despite the very limited resources and short development time of GECAm mission.

关键词： silicon photomultiplier Digital waveform processing Data acquisition