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271.
272.
Jun Zhang Yu-chun Li Jun-yi Huang Jia-xiang Wu Qiang Liu Shuang-zhang Wu Zhen-ru Gao Sheng Zhang Li Yang 《防务技术》2021,17(3):829-835
To study the thermal decomposition of Al/ZrH2/PTFE with different Al particle size as well as mechanical strength and impact sensitivity under medium and low strain rates, molding-vacuum sintering was adopted to prepare four groups of power materials and cylindrical specimens with different Al particle size. The active decomposition temperature of ZrH2 was obtained by TG-DSC, and the quasi-static me-chanics/reaction characteristics as well as the impact sensitivity of the specimen were studied respec-tively by quasi-static compression and drop-hammer test. The results show that the yield strength of the material decreased with the increase of the Al particle size, while the compressive strength, failure strain and toughness increased first and then decreased, which reached the maximum values of 116.61 MPa, 191%, and 119.9 MJ/m respectively when the Al particle size is 12—14μm because of particle size grading. The specimens with the highest strength and toughness formed circumferential open cracks and reacted partly when pressed. Those with developmental cracks formed inside did not react. It is considered that fracture of specimens first triggered initial reaction between Al and PTFE to release an amount of heat. Then ZrH2 was activated and decomposed, and participated in subsequent reaction to generate ZrC. The impact sensitivity of the specimens decreased with the increase of Al particle size. 相似文献
273.
Changing and optimizing the projectile nose shape is an important way to achieve specific ballistic performance. One special ballistic performance is the embedding effect, which can achieve a delayed high-explosive reaction on the target surface. This embedding effect includes a rebound phase that is significantly different from the traditional penetration process. To better study embedment behavior, this study proposed a novel nose shape called an annular grooved projectile and defined its interaction process with the ductile metal plate as partial penetration. Specifically, we conducted a series of low-velocity-ballistic tests in which these steel projectiles were used to strike 16-mm-thick target plates made with 2024-O aluminum alloy. We observed the dynamic evolution characteristics of this aluminum alloy near the impact craters and analyzed these characteristics by corresponding cross-sectional views and numerical simulations. The results indicated that the penetration resistance had a brief decrease that was influenced by its groove structure, but then it increased significantly-that is, the fluctuation of penetration resistance was affected by the irregular nose shape. Moreover, we visualized the distribution of the material in the groove and its inflow process through the rheology lines in microscopic tests and the highlighted mesh lines in simulations. The combination of these phenomena revealed the embed-ment mechanism of the annular grooved projectile and optimized the design of the groove shape to achieve a more firm embedment performance. The embedment was achieved primarily by the target material filled in the groove structure. Therefore, preventing the shear failure that occurred on the filling material was key to achieving this embedding effect. 相似文献
274.
A melt-cast Duan-Zhang-Kim (DZK) mesoscopic reaction rate model is developed for the shock initiation of melt-cast explosives based on the pore collapse hot-spot ignition mechanism. A series of shock initiation experiments was performed for the Comp B melt-cast explosive to estimate effects of the loading pressure and the particle size of granular explosive component, and the mesoscopic model is validated against the experimental data. Further numerical simulations indicate that the initial density and formula proportion greatly affect the hot-spot ignition of melt-cast explosives. 相似文献
275.
276.
黄英 《武警工程学院学报》2010,(1):46-49
《军语》选词对象的范围是军队各专业领域,包括各级指战员必须掌握的综合性用语和需要了解的专业性术语。在《军语》的实际编纂中,其选词范围的变异与规范并存。根据《军语》的性质,从主观和客观两方面的原因分析,《军语》选词范围变异主要涉及三个规范化问题。 相似文献
277.
《孙子兵法》中所蕴含的军队管理理念对部队的安全防事故工作有着高度的借鉴意义。从各级指挥员是部队安全防事故工作的主导,有效预防各类事故案件指挥员应具备综合的管理素质,明确部队安全防事故工作是全体官兵的共同责任三个方面,对《孙子兵法》在部队安全防事故中应用的合理性进行了分析。 相似文献
278.
黄献中 《军队政工理论研究》2010,11(1)
以问责为载体促进军事训练创新发展,要深刻认识推行军事训练问责的重大意义;积极探索军事训练问责的特点规律;努力提高军事训练问责的综合效益。 相似文献
279.
黄献中 《军队政工理论研究》2009,10(1)
落实"三个紧贴"战略要求,增强改进创新思想政治工作的实效,必须深刻理解"三个紧贴"的科学内涵,真正把思想统一到胡主席的重要指示精神上来;坚持以科学发展观为统领,切实把握好改进创新思想政治工作的目标导向;始终围绕理论联系实际这个核心,努力增强思想政治教育的实效性;加大党委对这项工作的领导和指导力度,切实提高加强改进创新思想政治工作的质量. 相似文献
280.
黄宏 《军队政工理论研究》2009,10(1)
提高党委贯彻党的根本制度质量,要把抓好民主集中制的学习作为防止和克服党委工作行政化的紧迫任务和基础工程来抓,打牢"一班人"思想基础;把深刻理解根本制度的科学内涵和基本要求作为防止和克服党委工作行政化的前提基础,切实澄清模糊认识;把加强检查督导作为防止和克服党委工作行政化的重要保证,切实发挥正副书记的表率作用和制度机制的约束作用. 相似文献