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141.
The disappointingly slow pace of progress on efforts to prevent proliferation, reduce nuclear weapons, and eliminate nuclear risks has many causes. The factor that might be easiest for individuals in the arms control and nonproliferation community to change stems from their own ambivalence about major questions that must be addressed on the road to reducing the number of nuclear weapons in the world to zero. This essay explores how ambivalence about four key issues—strategic stability, alliance relations, institution-building, and nuclear energy—often leads community members to take positions that play well at home and within their like-minded group but raise unintended impediments to achieving their own long-term goals. The author suggests alternative ways to handle these questions to improve the prospects for domestic and international agreement on practical measures that would eliminate, not perpetuate, nuclear risks.  相似文献   
142.
As many states in the Middle East are considering whether to embark on nuclear power programs, there is an urgent need to develop confidence-building measures to reassure states in the region that the programs are peaceful. One possible path would be to consider multilateral approaches to the fuel cycle in order to foster nuclear cooperation between states in the region, instead of each state going it alone, which would likely increase suspicions and the risk of a cascade of nuclear proliferation. With its policy of “zero problems with neighbors,” strategic connection to the West, and long-standing experience in the nuclear field, Turkey would be well-placed to take the lead on such a nuclear confidence-building agenda. Over time and under the right political conditions, Turkey could initiate or participate in measures including cooperation on nuclear education, safety and security, research and development, and joint fuel cycle facilities such as a regional fuel fabrication center.  相似文献   
143.
针对装药长径比对EFP成型的影响,基于一种球缺型药型罩EFP,利用ANSYS/LS-DYNA仿真软件对其成型过程进行建模仿真,研究EFP成型过程及其各项参数.在该基础上,改变装药高度得到不同的装药长径比数据,并对不同长径比EFP形成过程进行仿真,得到不同装药长径比EFP的速度、速度增长率及炸药能量利用率等数据,为选择最佳装药长径比提供依据.  相似文献   
144.
针对漂浮式微型波力发电装置,根据弗汝德·克雷洛夫假定法对几种常用形状浮子所受波浪力的大小进行了计算,得出垂直圆柱形浮子吸收波浪能效果最佳的结论;运用装置和浮子共振时吸收能量最大的原理,对垂直圆柱形浮子的基本参数进行了研究,为漂浮式微型波力发电装置捕浪器浮子的设计打下了基础。  相似文献   
145.
JXTA为构建对等网络提供了标准化计算平台,制定一些协议和服务专门解决构建P2P网络所遇见的问题.为了改进JXTA路由查询效率低下问题,提出一种路由短链改进算法.在端点路由协议的基础上,根据小世界短链现象采用物理邻居策略将网络划分簇,簇内采用Pastry算法,簇间运用freePastry算法进行资源搜索,使长跳路由减少短链路由增加.通过仿真实验说明,算法可有效增加检索效率,减少节点间的通讯时延.  相似文献   
146.
《防务技术》2022,18(10):1810-1821
In this paper, various core-shell structured Al–Ni@ECs composites have been prepared by a spray-drying technique. The involved ECs refer to the energetic composites (ECs) of ammonium perchlorate/nitrocellulose (AP/NC, NA) and polyvinylidene fluoride/hexanitrohexaazaisowurtzitane (PVDF/CL-20, PC). Two Al–Ni mixtures were prepared at atomic ratios of 1:1 and 1:3 and named as Al/Ni and Al/3Ni, respectively. The thermal reactivity and combustion behaviors of Al–Ni@ECs composites have been comprehensively investigated. Results showed that the reactivity and combustion performance of Al–Ni could be enhanced by introducing both NA and PC energetic composites. Among which the Al/Ni@NA composite exhibited higher reactivity and improved combustion performance. The measured flame propagation rate (v = 20.6 mm/s), average combustion wave temperature (Tmax = 1567.0 °C) and maximum temperature rise rate (γt = 1633.6 °C/s) of Al/Ni@NA are higher than that of the Al/Ni (v = 15.8 mm/s, Tmax = 858.0 °C, and γt = 143.5 °C/s). The enhancement in combustion properties could be due to presence of the acidic gaseous products from ECs, which could etch the Al2O3 shell on the surface of Al particles, and make the inner active Al to be easier transported, so that an intimate and faster intermetallic reaction between Al and Ni would be realized. Furthermore, the morphologies and chemical compositions of the condensed combustion products (CCPs) of Al–Ni@ECs composites were found to be different depending on the types of ECs. The compositions of CCPs are dominated with the Al–Ni intermetallics, combining with a trace amount of Al5O6N and Al2O3.  相似文献   
147.
《防务技术》2022,18(10):1852-1862
To improve the thermal properties of aluminum (Al) in the energetic system, a coated structure with ammonium perchlorate (AP) was prepared by a facile approach. And N, N-Dimethylformamide (DMF) was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics simulation. This coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal properties. The addition of AP could accelerate oxidation temperature of Al with around 17.5 °C. And the heat release of 85@15 composition rises to 26.13 kJ/g and the reaction degree is 97.6% with higher peak pressure (254.6 kPa) and rise rate (1.397 MPa/s). An ideal ratio with 15 wt% AP was probed primarily. The high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot field. And the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7 ± 55.9 m/s. In conclusion, 85@15 composition is expected to be applied in energetic system as a novel metal fuel.  相似文献   
148.
针对传统实验教学中存在的主要问题,对物理化学实验教学改革进行了一些有益的实践和探索,培养了学生的创新能力和综合素质,提高了教学质量。  相似文献   
149.
烟火药剂的热值计算在烟火研究领域有着重要的作用.本文根据最小自由能原理,通过一系列基本假设计算出了体系燃烧爆炸反应后的热值,计算结果与实验衡量数据相吻合,并且程序可通过进一步完善,扩展应用于非理想气体,提高计算精度.  相似文献   
150.
微积分是大学物理学中解决许多物理问题所采用的普遍方法,它和许多物理问题密切相关。对某类积分类型,从数学角度来求解,难度校大,如果对于这些复杂的数学积分问题,建立起相关的物理模型,就会使数学问题变得简单。  相似文献   
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