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文章速递500kV罐式断路器瓷质套管炸裂能量估算及仿真分析 认领
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作者 赵建利 姚树华 +1 位作者 刘卓 刘建军 《内蒙古电力技术》 2021年第1期42-45,共4页
某500 kV罐式断路器瓷质套管正常运行过程中发生炸裂故障,基于爆炸理论通过瓷质碎块数据测量及抛射速度计算、瓷质套管炸裂过程3D动态模拟,推算了瓷质套管化学炸裂和物理炸裂的能量范围及其炸裂机理。在此基础上,对瓷质套管炸裂的性质... 某500 kV罐式断路器瓷质套管正常运行过程中发生炸裂故障,基于爆炸理论通过瓷质碎块数据测量及抛射速度计算、瓷质套管炸裂过程3D动态模拟,推算了瓷质套管化学炸裂和物理炸裂的能量范围及其炸裂机理。在此基础上,对瓷质套管炸裂的性质和原因进行了仿真分析。结果表明:依据瓷块碎片抛射距离估算的瓷质套管化学炸裂能量为55~75 g的TNT当量,远大于其发生物理炸裂所产生的能量,瓷质套管炸裂性质属于化学爆炸。 展开更多
关键词 罐式断路器 瓷质套管 炸裂 抛射速度 炸裂能量
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Numerical analysis for the prediction of bump prone conditions:A southern Appalachian pillar coal bump case study 认领
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作者 Christopher Newman David Newman 《矿业科学技术学报:英文版》 SCIE EI 2021年第1期75-81,共7页
Two miners were fatally injured when a pillar bump occurred during retreat mining in a southern West Virginia coal mine.The mine was operating in the Eagle seam with overmining in the No.2 Gas and Powellton seams.A co... Two miners were fatally injured when a pillar bump occurred during retreat mining in a southern West Virginia coal mine.The mine was operating in the Eagle seam with overmining in the No.2 Gas and Powellton seams.A coal bump is defined as a sudden and violent failure of coal caused by the release of stored strain energy in the pillar.While significant strides have been made by academia,industry,and regulatory agencies to better understand bump conditions and mitigation techniques,coal bumps represent a long standing,highly site-specific engineering problem in which the exact failure mechanism is not clearly understood.In this case history,a cut-by-cut analysis of retreat mining operations was conducted on the 4 East Main leading up to the pillar bump event.Numerical input parameters were derived from site-specific geologic information and mine geometry for the analysis of pillar stress conditions and energy release using LaModel.An overview of stress conditions in the panel was presented including a precursor event that occurred two crosscuts inby the bump site.The methodology presented in the paper for the evaluation of the fatal bump event can be used for the identification of bump prone conditions prior to development and retreat of a mining area. 展开更多
关键词 BUMP BURST Coal Energy release rate LaModel Numerical modeling
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连续梁桥腹板预应力束崩裂回缩影响分析 认领
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作者 杨耀 《工程建设》 2021年第1期38-42,共5页
本文结合高速铁路中的三跨连续梁、T构连续梁和道岔连续梁3种代表性桥型,基于有限元分析软件Midas Civil,采用数值分析方法计算分析施工期间腹板预应力束崩裂回缩对梁体应力的影响。结果表明:当腹板预应力束压浆后崩裂回缩10 mm时,三跨... 本文结合高速铁路中的三跨连续梁、T构连续梁和道岔连续梁3种代表性桥型,基于有限元分析软件Midas Civil,采用数值分析方法计算分析施工期间腹板预应力束崩裂回缩对梁体应力的影响。结果表明:当腹板预应力束压浆后崩裂回缩10 mm时,三跨连续梁桥梁体应力影响较小;T构连续梁桥顶板应力最大减小0.29 MPa,底板应力最大增加0.09 MPa;道岔连续梁桥顶板应力最大减小0.22 MPa,底板应力最大增加0.32 MPa,最大减小0.18 MPa;3种桥型腹板的主拉应力影响较小,主压应力最大减小0.16 MPa。 展开更多
关键词 连续梁桥 预应力损失 崩裂
Pillar design and coal burst experience in Utah Book Cliffs longwall operations 认领
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作者 Christopher Mark Michael Gauna 《矿业科学技术学报:英文版》 SCIE EI 2021年第1期33-41,共9页
Longwall mining has existed in Utah for more than half a century.Much of this mining occurred at depths of cover that significantly exceed those encountered by most other US longwall operations.Deep cover causes high ... Longwall mining has existed in Utah for more than half a century.Much of this mining occurred at depths of cover that significantly exceed those encountered by most other US longwall operations.Deep cover causes high ground stress,which can combine with geology to create a coal burst hazard.Nearly every longwall mine operating within the Utah’s Book Cliffs coalfield has been affected by coal bursts.Pillar design has been a key component in the burst control strategies employed by mines in the Book Cliffs.Historically,most longwall mines employed double-use two-entry yield pillar gates.Double-use signifies that the gate system serves first as the headgate,and then later serves as the tailgate for the adjacent panel.After the 1996 burst fatality at the Aberdeen Mine,the inter-panel barrier design was introduced.In this layout,a wide barrier pillar protects each longwall panel from the previously mined panel,and each gate system is used just once.This paper documents the deep cover longwall mining conducted with each type of pillar design,together with the associated coal burst experience.Each of the six longwall mining complexes in the Book Cliffs having a coal burst history is described on a panel-by-panel basis.The analysis shows that where the mining depth exceeded 450 m,each design has been employed for about 38000 total m of longwall panel extraction.The double-use yield pillar design has been used primarily at depths less than 600 m,however,while the inter-panel barrier design has been used mainly at depths exceeding 600 m.Despite its greater depth of use,the inter-panel barrier gate design has been associated with about one-third as much face region burst activity as the double-use yield pillar design. 展开更多
关键词 LONGWALL Ground control Coal burst Pillar design Yield pillar
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复掺纤维对RPC高温后力学性能及超声规律的影响 认领
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作者 刘晓仙 杜红秀 徐瑶瑶 《混凝土》 CAS 北大核心 2021年第1期87-90,97,共5页
为了提高活性粉末混凝土(RPC)的力学性能并改善其高温爆裂性,在RPC中将0.3%、0.4%聚丙烯纤维(PP)和0、1%、2%、3%钢纤维(S)组合复掺,共设计8组试件,养护并模拟火灾试验,统计试件在高温(200、400、600℃)作用下的爆裂情况,研究复掺纤维... 为了提高活性粉末混凝土(RPC)的力学性能并改善其高温爆裂性,在RPC中将0.3%、0.4%聚丙烯纤维(PP)和0、1%、2%、3%钢纤维(S)组合复掺,共设计8组试件,养护并模拟火灾试验,统计试件在高温(200、400、600℃)作用下的爆裂情况,研究复掺纤维对高温后RPC的抗折和抗压强度、强度损失率、折压比的影响,抗压强度、受火温度与超声波速的规律,确定两种纤维的最佳配合比。结果表明:掺入PP可以改善RPC高温爆裂;RPC抗折、抗压强度、折压比及超声波速随受火温度升高均呈先上升再下降的趋势,复掺入S可提升RPC的抗压、抗折强度和折压比;当S与PP掺量分别为1%与0.3%、2%、0.4%时,RPC未爆裂且强度较高,超声波速与抗压强度的相关性也较高。 展开更多
关键词 复掺纤维 活性粉末混凝土 高温 爆裂 力学性能 超声波速
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文章速递情感与社会行为的神经机制研究进展 认领
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作者 胡海岚 《中国科学:生命科学》 CSCD 北大核心 2021年第2期105-115,共11页
人类对大脑机制的研究首先在对外在的感知系统中取得了长足的进展,继而在学习与记忆的脑机制上获得了突破,目前已经迈进到精神领域.情绪不仅使生活多姿多彩,而且也深刻地影响着人们的行为和抉择.同时作为社会动物,人的情绪又受到在社会... 人类对大脑机制的研究首先在对外在的感知系统中取得了长足的进展,继而在学习与记忆的脑机制上获得了突破,目前已经迈进到精神领域.情绪不仅使生活多姿多彩,而且也深刻地影响着人们的行为和抉择.同时作为社会动物,人的情绪又受到在社会结构中与他人的关系及在群体中的行为的调节.情绪与行为的障碍都可能导致精神疾病,如抑郁症的发生.近十年来,随着动物活体影像技术及光遗传、化学遗传等神经操纵技术的广泛应用,脑科学家们有了在空间和时间上更精准操纵行为的实验方法,人类对情绪情感、社会行为及精神疾病的脑机制及其相互作用的探索正从相关性分析走向因果性理论.本综述以情感效价、社会竞争和抑郁症的神经机制为例,结合本团队的研究工作,讨论了近年来神经生物学领域在这几个方向上的研究进展. 展开更多
关键词 情感效价 社会等级 社会竞争 胜利者效应 抑郁症 氯胺酮 簇状放电 前额叶皮层 外侧缰核
文章速递The physics of fast radio bursts 认领
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作者 Di Xiao FaYin Wang ZiGao Dai 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2021年第4期35-66,共32页
In 2007, a very bright radio pulse was identified in the archival data of the Parkes Telescope in Australia, marking the beginning of a new research branch in astrophysics. In 2013, this kind of millisecond bursts wit... In 2007, a very bright radio pulse was identified in the archival data of the Parkes Telescope in Australia, marking the beginning of a new research branch in astrophysics. In 2013, this kind of millisecond bursts with extremely high brightness temperature takes a unified name, fast radio burst(FRB). Over the first few years, FRBs seemed very mysterious because the sample of known events was limited. With the improvement of instruments over the last five years, hundreds of new FRBs have been discovered.The field is now undergoing a revolution and understanding of FRB has rapidly increased as new observational data increasingly accumulate. In this review, we will summarize the basic physics of FRBs and discuss the current research progress in this area.We have tried to cover a wide range of FRB topics, including the observational property, propagation effect, population study,radiation mechanism, source model, and application in cosmology. A framework based on the latest observational facts is now under construction. In the near future, this exciting field is expected to make significant breakthroughs. 展开更多
关键词 fast radio burst neutron star cosmology
一种基于NVMeoF存储池的分域共享并发存储架构 认领
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作者 李琼 宋振龙 +1 位作者 袁远 谢徐超 《计算机工程与科学》 CSCD 北大核心 2020年第10期1711-1719,共9页
E级计算和大数据时代,为了充分利用超级计算机系统的并行计算能力,许多大数据应用程序在高性能计算HPC系统上运行,超级计算机的I/O模式更趋复杂,I/O瓶颈问题日益严峻。当前基于闪存的存储阵列或存储服务器已逐步应用在高性能计算机的并... E级计算和大数据时代,为了充分利用超级计算机系统的并行计算能力,许多大数据应用程序在高性能计算HPC系统上运行,超级计算机的I/O模式更趋复杂,I/O瓶颈问题日益严峻。当前基于闪存的存储阵列或存储服务器已逐步应用在高性能计算机的并行存储系统中,但传统存储体系结构、I/O协议软件栈和存储网络的较高延迟使得新型存储介质不能发挥性能优势,存储系统依然存在I/O访问延迟高、并发I/O吞吐率和瞬发I/O(Burst I/O)带宽受限的问题。针对上述问题和技术挑战,提出了一种基于非易失存储介质NVM的分域共享并发存储架构,设计了一种支持NVMeoF网络存储的Burst I/O缓冲存储池NV-BSP,实现了虚拟化存储池资源管理、基于天河高速互连网的NVMeoF网络存储通信等关键技术,具有横向和纵向扩展能力,可有效支持面向特定计算任务的Burst I/O加速和低延迟远程存储访问。基于HPC和大数据应用程序混合运行性能分析模型,提出了一种混合应用程序QoS控制策略。小规模验证系统上的性能测评结果表明:NV-BSP存储池的读写性能可随并发I/O处理线程数良好扩展;与Linux操作系统自带的MD-RAID相比具有明显的性能优势;相比本地I/O访问,基于天河互连网络的NVMeoF远程存储读写延迟仅增加了59.25μs和54.03μs。通过计算与存储分离,NV-BSP在提供堪比本地存储池性能的同时,提高了系统存储资源动态调配的灵活性和系统可靠性。 展开更多
关键词 存储系统结构 Burst Buffer NVMe SSD NVMeoF 高性能计算 大数据
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The Remnant of Neutron Star-White Dwarf Merger and the Repeating Fast Radio Bursts 认领
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作者 Xiang Liu 《天文学与天体物理学国际期刊(英文)》 2020年第1期28-38,共11页
Fast radio bursts (FRBs) at cosmological distances still hold concealed physical origins. Previously Liu (2018) proposes a scenario that the collision between a neutron star (NS) and a white dwarf (WD) can be one of t... Fast radio bursts (FRBs) at cosmological distances still hold concealed physical origins. Previously Liu (2018) proposes a scenario that the collision between a neutron star (NS) and a white dwarf (WD) can be one of the progenitors of non-repeating FRBs and notices that the repeating FRBs can also be explained if a magnetar formed after such NS-WD merger. In this paper, we investigate this channel of magnetar formation in more detail. We propose that the NS-WD post-merger, after cooling and angular momentum redistribution, may collapse to either a black hole or a new NS or even remains as a hybrid WDNS, depending on the total mass of the NS and WD. In particular, the newly formed NS can be a magnetar if the core of the WD collapsed into the NS while large quantities of degenerate electrons of the WD compressed to the outer layers of the new NS. A strong magnetic field can be formed by the electrons and positive charges with different angular velocities induced by the differential rotation of the newborn magnetar. Such a magnetar can power the repeating FRBs by the magnetic reconnections due to the crustal movements or starquakes. 展开更多
关键词 Pulsar Neutron Star White DWARF MERGER Magnetic Field MAGNETAR FAST Radio Burst
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World-Universe Model—Alternative to Big Bang Model 认领
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作者 Vladimir S. Netchitailo 《高能物理(英文)》 2020年第1期133-158,共26页
This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the ... This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the Standard Cosmology are model-dependent and not strong enough to support the model. The angular momentum problem is one of the most critical problems in BBM. Standard Cosmology cannot explain how Galaxies and Extra Solar systems obtained their substantial orbital and rotational angular momenta, and why the orbital momentum of Jupiter is considerably larger than the rotational momentum of the Sun. WUM is the only cosmological model in existence that is consistent with the Law of Conservation of Angular Momentum. To be consistent with this Fundamental Law, WUM discusses in detail the Beginning of the World. The Model introduces Dark Epoch (spanning from the Beginning of the World for 0.4 billion years) when only Dark Matter Particles (DMPs) existed, and Luminous Epoch (ever since for 13.8 billion years). Big Bang discussed in Standard Cosmology is, in our view, transition from Dark Epoch to Luminous Epoch due to Rotational Fission of Overspinning Dark Matter (DM) Supercluster’s Cores. WUM envisions Matter carried from the Universe into the World from the fourth spatial dimension by DMPs. Ordinary Matter is a byproduct of DM annihilation. WUM solves a number of physical problems in contemporary Cosmology and Astrophysics through DMPs and their interactions: Angular Momentum problem in birth and subsequent evolution of Galaxies and Extrasolar systems—how do they obtain it;Fermi Bubbles—two large structures in gamma-rays and X-rays above and below Galactic center;Diversity of Gravitationally-Rounded Objects in Solar system;some problems in Solar and Geophysics [1]. WUM reveals Inter-Connectivity of Primary Cosmological Parameters and calculates their values, which are in good agreement with the latest results of their measurements. 展开更多
关键词 Big Bang MODEL Four Pillars of Standard Cosmology ANGULAR MOMENTUM Problem Black Holes Hypersphere World-Universe MODEL Multicomponent DARK MATTER Macroobjects Structure Law of Conservation of ANGULAR MOMENTUM Medium of the World Inter-Connectivity of Primary Cosmological Parameters The Beginning of the World DARK EPOCH Rotational Fission Luminous EPOCH Macroobject Shell MODEL DARK MATTER Core Gravitational Burst Intergalactic Plasma Microwave Background Radiation Far-Infrared Background Radiation Emergent Phenomena CODATA
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Numerical Simulation of the Relationship between the Width of Destressed Zone and Blasthole Depth 认领
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作者 Jiansheng Tian Qingru Wu Zhijun Liu 《工程(英文)(1947-3931)》 2020年第4期269-279,共11页
Overstress in the surrounding rock of the roadway is a key reason that causes failures of deep roadways. Destressing blasting is one of the promising techniques that could improve the supporting quality. If the depth ... Overstress in the surrounding rock of the roadway is a key reason that causes failures of deep roadways. Destressing blasting is one of the promising techniques that could improve the supporting quality. If the depth of the pressure relief blast hole is too shallow, the surrounding rock of the roadway will be broken or even collapsed. If the pressure relief blast hole is too deep, the pressure relief area will be located in the deep part of the surrounding rock of the roadway, which cannot achieve the purpose of releasing the stress in the shallow part of the surrounding rock and cause waste of the blast hole. The width or range of the pressure relief area should just fall in the high stress area of the surrounding rock of the roadway, so the pressure relief blast hole should have a reasonable depth. In order to quantitatively describe the relationship between borehole depth and the width of the stress relief zone, numerical simulations were carried out in ANSYS according to different borehole depths. The results show that the optimal destressing effect is achieved when borehole depth is 4 m. Peak stress of and is significantly reduced by 30.51% and 49.07% after blasting. Meanwhile, the high-stress area shifts about 4.8 m from the roadside to the depth of surrounding rock, thus a 3.8 m wide stress relief zone is formed around the roadside, thus, the aim of quantizing the effects of destress blasting is achieved. 展开更多
关键词 Rock BURST Deep ROADWAY Supporting WIDTH of Stress RELIEF ZONE Destress BLASTING Numerical Simulation
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Theoretical Study of Coupling Mechanism between FBG and Shock Waves of Rock Burst 认领
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作者 Shiming Wei Zesheng Zhang Yao Wang 《世界工程和技术(英文)》 2020年第4期784-791,共8页
To achieve the monitor of rock burst in coal mine with fiber Bragg grating (FBG) sensing, the coupling mechanism between FBG and shock waves w<span style="font-family:;" "="">as</span... To achieve the monitor of rock burst in coal mine with fiber Bragg grating (FBG) sensing, the coupling mechanism between FBG and shock waves w<span style="font-family:;" "="">as</span><span style="font-family:;" "=""> theoretically analyzed. Based on Housner’s random shock model, the coupling mechanism between shock waves and FBG was theoretically analyzed. The result shows that the wave will change the period </span><span><span style="white-space:nowrap;">&#581</span></span><span style="font-family:;" "=""> and effective refractive index </span><i><span style="font-family:;" "="">n</span></i><span style="font-family:;" "=""> of FBG, and further affect the initial wavelength value. The amplitude, phase and frequency of shock wave are directly related to the wavelength drifts of FBG. The transmitting velocity of shock wave in rock is affected by lithologic characteristics. The Elastic modulus, density and Poisson’s ratio of rock influence the initial wavelength value of FBG. This study provided a theoretical basis and practical application guidance for coal or rock burst monitoring with FBG sensing.</span> 展开更多
关键词 Rock Burst FBG Shock Waves Lithological Characteristics
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Q245R钢锅炉管爆管原因 认领 被引量:1
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作者 李建宾 钦祥斗 《理化检验:物理分册》 CAS 2020年第10期42-46,共5页
某公司Q245R钢锅炉管在使用仅8个月时发生了横向爆管事故。通过宏观观察、化学成分分析、硬度测试、金相检验、扫描电镜分析、X射线衍射分析等方法对锅炉管的爆管原因进行了分析。结果表明:该Q245R钢锅炉管所通水蒸气中NaCl,Na2CO3等杂... 某公司Q245R钢锅炉管在使用仅8个月时发生了横向爆管事故。通过宏观观察、化学成分分析、硬度测试、金相检验、扫描电镜分析、X射线衍射分析等方法对锅炉管的爆管原因进行了分析。结果表明:该Q245R钢锅炉管所通水蒸气中NaCl,Na2CO3等杂质较多,使得管道转弯处堵塞变窄,前段管内蒸汽流速和温度异常。在高温高压和腐蚀介质作用下,管内壁不断被氧化,管壁减薄并脱碳,管子强度大幅降低,不足以承受工作压力,最终导致爆管。 展开更多
关键词 Q245R钢 锅炉管 爆管 应力腐蚀
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OD1422 mm X80钢管低温爆破试验研究 认领
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作者 谢萍 李鹤 《石油管材与仪器》 2020年第1期40-42,47共4页
为了降低我国低温服役管材失效概率,掌握X80钢级管材低温性能,研究了一套低温爆破试验技术和方法,开发了低温爆破试验装置,在-5℃下开展了1次OD1422 mm X80钢管全尺寸低温爆破试验。通过试验得到了裂纹扩展速度和断口形貌,试验结果表明... 为了降低我国低温服役管材失效概率,掌握X80钢级管材低温性能,研究了一套低温爆破试验技术和方法,开发了低温爆破试验装置,在-5℃下开展了1次OD1422 mm X80钢管全尺寸低温爆破试验。通过试验得到了裂纹扩展速度和断口形貌,试验结果表明:在初始裂纹扩展速度达到200 m/s以上的情况下,该规格管材可依靠自身韧性将裂纹扩展速度降到100 m/s以下,实现低温止裂;同时试验钢管断口形貌与DWTT断口形貌相吻合,验证了DWTT试验方法的有效性。 展开更多
关键词 钢管 低温 爆破 试验研究
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70MPa高压氢气瓶阀液压爆破试验 认领
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作者 刘冬明 王东雨 +3 位作者 刘仁豪 薛东彪 孙福龙 郭淑芬 《低温与特气》 CAS 2020年第6期44-46,共3页
70 MPa高压瓶阀为储氢系统的关键零部件,有密封气瓶、控制气体导通关闭的作用,其安全性能对整个储氢系统及燃料电池汽车起着关键的作用。瓶阀的安全性需要通过型式试验进行验证,而液压爆破试验是保证其安全性的最基本、最重要的测试之... 70 MPa高压瓶阀为储氢系统的关键零部件,有密封气瓶、控制气体导通关闭的作用,其安全性能对整个储氢系统及燃料电池汽车起着关键的作用。瓶阀的安全性需要通过型式试验进行验证,而液压爆破试验是保证其安全性的最基本、最重要的测试之一。主要分析瓶阀液压爆破试验失效方式并与理论计算进行对比。 展开更多
关键词 氢气 高压 瓶阀 爆破
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Picosecond burst pulse machining with temporal energy modulation [Invited] 认领
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作者 Akinao Nakamura Tomoki Mizuta +4 位作者 Yasuhiko Shimotsuma Masaaki Sakakura Tomohito Otobe Masahiro Shimizu Kiyotaka Miura 《中国光学快报:英文版》 SCIE EI CAS CSCD 2020年第12期83-87,共5页
Suppression of stress and crack generation during picosecond laser processing in transparent brittle materials such as glass was successfully demonstrated by a picosecond laser pulse with temporal energy modulation.Th... Suppression of stress and crack generation during picosecond laser processing in transparent brittle materials such as glass was successfully demonstrated by a picosecond laser pulse with temporal energy modulation.The origin of deterioration in processing accuracy could be interpreted in terms of the discontinuous movement of plasma in the vicinity of the focus.To reveal the effectiveness of the temporal energy modulation for smootli machining,such plasma motion was simulated by the fiidtc-d ifference time-domain method.F urt her more,photoinduced birefringence was observed using a high-speed polarization camera. 展开更多
关键词 picosecond laser energy modulation burst pulse material processing stress distribution
12Cr1MoV钢管爆管失效分析 认领
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作者 张彦文 王志奋 +1 位作者 韩荣东 陶勇 《焊管》 2020年第8期38-41,46,共5页
为了研究12Cr1MoV钢管在使用过程中早期爆管失效的原因,通过宏观观察、扫描电镜分析、光学显微观察等方法对失效钢管进行了分析。结果表明:钢管在较高温度、高压下运行,长期受管内腐蚀性介质冲蚀,局部内壁不断减薄,同时减薄部位出现蠕... 为了研究12Cr1MoV钢管在使用过程中早期爆管失效的原因,通过宏观观察、扫描电镜分析、光学显微观察等方法对失效钢管进行了分析。结果表明:钢管在较高温度、高压下运行,长期受管内腐蚀性介质冲蚀,局部内壁不断减薄,同时减薄部位出现蠕变孔洞;当减薄及蠕变孔洞发展到不足以承受管内压力时,导致爆管失效。对此,可通过提高管内过热蒸汽纯净度减少对管壁的腐蚀等途径加以解决。 展开更多
关键词 钢管 爆裂 腐蚀 减薄 蠕变
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某型燃气发生器壳体爆裂故障分析 认领
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作者 谢七国 《航空维修与工程》 2020年第10期101-103,共3页
针对某型装备燃气发生器使用过程中发生壳体爆裂的故障,分析了该型燃气发生器爆裂的原因,提出了改进措施建议。
关键词 燃气发生器 壳体 爆裂 故障分析
Progress on SVOM Satellite Development 认领
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作者 WEI Jianyan 《空间科学学报》 CAS CSCD 北大核心 2020年第5期698-699,共2页
SVOM(Space-based multiband astronomical Variable Objects Monitor)is a Chinese-French space mission dedicated to studying Gamma-Ray Bursts.The satellite has four instruments to detect and localize the prompt GRB emissi... SVOM(Space-based multiband astronomical Variable Objects Monitor)is a Chinese-French space mission dedicated to studying Gamma-Ray Bursts.The satellite has four instruments to detect and localize the prompt GRB emission and measure the evolution of the afterglow in the visible band and in X-rays,and a VHF communication system enabling the fast transmission of SVOM alerts to the ground.The ground segment includes an array of wide-angle cameras and two follow-up telescopes.It was planned to be in orbit in 2021,and now has to be delayed about six months because of COVID-19 epidemic. 展开更多
关键词 Space astronomy Gamma-ray burst
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锦屏一级水电站中孔充压水封破裂原因分析及防范措施 认领
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作者 梁小飞 杨维平 +3 位作者 广波 何晨阳 朱生学 杨光波 《四川水力发电》 2020年第6期105-107,129,共4页
锦屏一级水电站4号中孔工作闸门无水启闭试验时,充压水封发生了破裂。笔者通过详细分析中孔工作闸门无水启闭试验过程,结合中孔工作闸门开度与充压水封压力曲线图,找出闸门开度检测异常是造成4号中孔充压水封破裂的原因。通过优化程序... 锦屏一级水电站4号中孔工作闸门无水启闭试验时,充压水封发生了破裂。笔者通过详细分析中孔工作闸门无水启闭试验过程,结合中孔工作闸门开度与充压水封压力曲线图,找出闸门开度检测异常是造成4号中孔充压水封破裂的原因。通过优化程序等防范措施,有效避免了因闸门开度检测异常导致充压水封破裂。给同类型水电站预防及处理类似问题提供参考。 展开更多
关键词 中孔 充压水封 破裂 原因分析 防范
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