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排序方式: 共有683条查询结果,搜索用时 15 毫秒
201.
爆炸试验室基础隔振系统设计与应用 总被引:1,自引:0,他引:1
针对某爆炸试验室的基础隔振系统的改造,首先提出了一种由钢丝绳和碟形弹簧组合而成的新型隔振器,给出了相应的基础隔振方案,并对组合隔振器进行了试验研究。然后,采用两自由度、有阻尼计算模型对隔振系统的动力反应进行非线性分析,研究了隔振层刚度和阻尼对隔振系统动力反应的影响,优化选择了隔振系统的有关参数。研究结果表明,当隔振层刚度约为110 kN/mm,阻尼比为0.20~0.35时,隔振层动荷载接近最小,且其他动力反应满足设计要求。改造后的爆炸实验室的抗冲击能力比改造前提高了50%。 相似文献
202.
203.
导出了金属管爆炸胀形估算炸药传递到工件表面能量几何法公式,该法以炸药的比能为基础进行计算,避免了能量法对大多数炸药缺少能量常数C和G试验数据的困难,因而可扩大各种炸药在金属管爆炸胀形中的应用。为炸药用量的估算提供一简单的方法。 相似文献
204.
Atomic diffusion across Ni_(50)Ti_(50)Cu explosive welding interface:Diffusion layer thickness and atomic concentration distribution
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Molecular dynamics simulations are carried out to study atomic diffusion in the explosive welding process of Ni50Ti50–Cu(at.%). By using a hybrid method which combines molecular dynamics simulation and classical diffusion theory, the thickness of the diffusion layer and the atomic concentration distribution across the welding interface are obtained.The results indicate that the concentration distribution curves at different times have a geometric similarity. According to the geometric similarity, the atomic concentration distribution at any time in explosive welding can be calculated. Ni50Ti50–Cu explosive welding and scanning electron microscope experiments are done to verify the results. The simulation results and the experimental results are in good agreement. 相似文献
205.
将纯铝用熔喷法制成铝纤维添加到炸药中,得到新型非理想混合炸药,通过水中爆炸实验,测试不同位置铝纤维炸药的压力时程曲线。对压力时程曲线进行分析,计算得到水下不同位置铝纤维炸药的冲击波压力峰值、冲量、冲击波能和气泡能。结果表明:铝纤维炸药的压力时程曲线可采用指数函数与双曲线函数进行分段描述,而用正态分布函数拟合气泡脉动压力曲线的效果不理想;铝纤维炸药水下爆炸比气泡能与总能量的比值为52%~58%,说明向基体炸药RDX中添加铝纤维对总能量有影响;总能量与爆热的比值为75%~85%,小于理论近似值(100%),说明铝纤维炸药爆炸时铝纤维反应不完全且破碎铝纤维消耗了一定的能量。 相似文献
206.
Lee Chuin Chen Md. Matiur Rahman Kenzo Hiraoka 《Journal of mass spectrometry : JMS》2013,48(3):392-398
Super‐atmospheric pressure chemical ionization (APCI) mass spectrometry was performed using a commercial mass spectrometer by pressurizing the ion source with compressed air up to 7 atm. Similar to typical APCI source, reactant ions in the experiment were generated with corona discharge using a needle electrode. Although a higher needle potential was necessary to initiate the corona discharge, discharge current and detected ion signal were stable at all tested pressures. A Roots booster pump with variable pumping speed was installed between the evacuation port of the mass spectrometer and the original rough pumps to maintain a same pressure in the first pumping stage of the mass spectrometer regardless of ion source pressure. Measurement of gaseous methamphetamine and research department explosive showed an increase in ion intensity with the ion source pressure until an optimum pressure at around 4–5 atm. Beyond 5 atm, the ion intensity decreased with further increase of pressure, likely due to greater ion losses inside the ion transport capillary. For benzene, it was found that besides molecular ion and protonated species, ion due to [M + 2H]+ which was not so common in APCI, was also observed with high ion abundance under super‐atmospheric pressure condition. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
207.
飞板运动姿态的测定是爆炸焊接机理研究的基础,针对传统电测方法存在干扰因素多、易产生弯曲波等缺陷,设计了一种适用于野外大当量下爆炸焊接飞板姿态实验的连续电阻测试方法。研制了3种不同结构的梯形支架型连续电阻探针元件,利用有限元程序分析了探针的导通压力和响应时间,在此基础上,对3种探针实施了爆炸焊接实验,实验结果表明:金属丝网型探针元件具有最优的导通效果,各段测试曲线光滑无毛刺。以该探针数据计算获得了待测飞板的运动姿态曲线,并与Richter简化模型下的近似计算公式结果进行了对比,两者基本一致。所述测试方法实现了炸药爆速和飞板变形曲线的连续、可靠和快速测量,为滑移爆轰驱动问题、爆轰产物状态方程等的研究提供了测试方法补充。 相似文献
208.
Scott I. Jackson Charles B. Kiyanda Mark Short 《Proceedings of the Combustion Institute》2011,33(2):2219-2226
Detonations in explosive mixtures of ammonium-nitrate-fuel-oil (ANFO) confined by aluminum allow for transport of detonation energy ahead of the detonation front due to the aluminum sound-speed exceeding the detonation velocity. The net effect of this energy transport on the detonation is unclear. It could enhance the detonation by precompressing the explosive near the wall. Alternatively, it could decrease the explosive performance by crushing porosity required for initiation by shock compression or destroying confinement ahead of the detonation. At present, these phenomena are not well understood. But with slowly detonating, non-ideal high explosive (NIHE) systems becoming increasing prevalent, proper understanding and prediction of the performance of these metal-confined NIHE systems is desirable. Experiments are discussed that measured the effect of ANFO detonation energy transported upstream of the front by a 76-mm-inner-diameter aluminum confining tube. Detonation velocity, detonation front-shape, and aluminum response are recorded as a function of confiner wall thickness and length. Detonation shape profiles display little curvature near the confining surface, which is attributed to energy transported upstream modifying the flow. Average detonation velocities were seen to increase with increasing confiner thickness, while wavefront curvature decreased due to the stiffer, subsonic confinement. Significant radial sidewall tube motion was observed immediately ahead of the detonation. Axial motion was also detected, which interfered with the front-shape measurements in some cases. It was concluded that the confiner was able to transport energy ahead of the detonation and that this transport has a definite effect on the detonation by modifying its characteristic shape. 相似文献
209.
The application of polymeric films as alarms for explosive materials is a critical issue these days as mandated by homeland security requirements. Amongst the multiple advantageous points of applying polymer films in this area is the fact that they are cheap material, so they can be applied on a broad scale for low cost. The basic idea of the current work is based on the fact that common explosives are electron deficient because of the existence of the nitro‐groups in their chemical structures, and this causes their high affinities towards electron rich materials to form charge‐transfer complex. Our endeavor is to trace any charge‐transfer complex formation, which would definitely cause a recognizable change in their physical properties. These changes in the polymers' physical properties could be utilized as alerts for the existence of explosive materials, especially if such changes could be incorporated into sophisticated electronic circuits that would give strong for traces of explosives. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
210.
本文依据有壳梯黑(35/65)装药部件的贮存检测数据,应用统计回归分析,拟合出该装药的密度下降规律,以及年均体膨胀率,发现该装药在贮存过程中的体积长大确是一个不容忽视的问题,特别是当具有坚固外壳时,这种体胀率会转化成内应力,所以必须给予充分的重视。 相似文献