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281.
In February 2012, Iran announced its willingness to resume negotiations with the Western powers. This statement followed in the wake of a damning report by the International Atomic Energy Agency (IAEA) Board of Governors and the imposition of additional sanctions by the international community on an Iranian economy already under pressure. Tehran's announcement also coincided with increased speculation regarding an Israeli military strike on Iranian nuclear facilities. At the same time, however, this seemingly positive step appeared to be undermined by Iran's concomitant announcement that “huge” technical progress has been made on Iran's nuclear programme. This article will explore the significance of the recent political, diplomatic and technical developments in the Iranian nuclear affair and situate them in the broader context of Tehran's nuclear strategy. The analysis will assess the potential for this latest phase in the Iranian nuclear crisis to reverse Iran's current trajectory and initiate a rapprochement between Iran and Western powers.  相似文献   
282.
从核电站压水堆动力装置在运行中ΔT超温度 /超功率保护功能出发 ,介绍了压水堆ΔT超温度 /超功率保护系统 ,分析了确定极限限制线以及保护区的方法 ,并对此作出了评价 .  相似文献   
283.
高硬热喷涂层的缓进给切削试验   总被引:1,自引:0,他引:1  
采用高硬材料切削过程中常用的2种刀具材料CBN和YG610,应用缓进给的模式对高硬喷涂层进行切削试验。试验结果表明:采用小进给切削模式YG610刀具切削高硬热喷涂层可以获得较理想的刀具耐用度,并且加工表面质量可以达到Ra1以下,具备了以车代磨的基本条件。高硬材料切削常用的刀具CBN在切削过程中出现了较严重的非正常破损现象。通过对试验现象的分析,可以认为冲击性和高硬度的同时存在是喷涂层切削的最重要特性。因此,喷涂层切削刀具需要同时具备较高的韧性和硬度。  相似文献   
284.
聚合物材料具有的易燃性或可燃性使其在实际应用中具有潜在的火灾危险性,正确分析评价聚合物材料的火灾危险性,对材料的安全使用和火灾预防与控制具有重要的作用。在综述文献的基础上,根据火灾危害的特征,对聚合物材料的引燃、热释放和火焰传播等热危险性进行了分析和总结,并提出了相应的预防对策。  相似文献   
285.
在已建立的应力波传播模型和研究弹、板间作用力所获结果的基础上,为分析复合板应力的变化,对复合板弹板碰撞承受的应力进行了简化处理,根据应力波传播特性,确定了复合板内能量集中区域,研究了应力波在复合板巾的传播和能耗,并讨论了应力波对陶瓷的作用。通过近似计算,发现烧蚀消耗的弹丸动能较大,在复合板中,Al板的塑性变形吸收了19%的弹丸动能。  相似文献   
286.
African states' attendance at and participation in the preparations for the 2015 Review Conference of the Parties to the Treaty on the Non-proliferation of Nuclear Weapons (NPT) has produced mixed results, with the continent acting as both agent and bystander in respect of certain issues. African agency is evident in, for example, its position as a member of groupings on Iran's nuclear weapons programme and the Middle East Nuclear Weapons Free Zone. Less agency is evident in states' individual actions. This underscores the importance of African states' preference for multilateralism. However, African agency is also less evident in African multilateral efforts at the NPT preparatory meetings. The impact of these developments on the 2015 NPT Review Conference is too soon to tell but may bode ill for African agency.  相似文献   
287.
“French nuclear diplomacy” is the French government's use of civilian nuclear cooperation agreements (NCAs) to advance specific commercial and strategic interests. During the heart of the so-called nuclear renaissance, the Élysée Palace aggressively peddled France's nuclear expertise and technology abroad, signing over a dozen new NCAs in an effort to bring in business for the French industry, forge diplomatic relationships, and promote global nonproliferation norms. Several years later, however, the outcomes of France's aggressive global nuclear power push appear nominal at best. This article explores the mixed results of this nuclear campaign, and through three case studies, illustrates how many of France's commercial and political disappointments stem from unrealistic expectations and the disorganization of the French nuclear complex.  相似文献   
288.
This article examines Kazakhstani nuclear decision making from December 1991 to May 1992. The study is based on unique archival data and reveals how Kazakhstan's policy makers solved a nuclear dilemma that the nation faced in its first years of independence. The article reconstructs the internal policy-making process behind the decision made by President Nursultan Nazarbayev and his circle of advisors to accept non-nuclear status. The author argues that Almaty elaborated a deliberately ambivalent strategy toward the republic's nuclear status with the aim of maximizing the state's strategic interests. The article reviews external pressures affecting Nazarbayev's course of action and discusses policy options articulated during this period.  相似文献   
289.
The question of nuclear stability in South Asia is a subject of both academic and policy significance. It is the only region in the world that has three, contiguous nuclear-armed states: India, the People's Republic of China, and Pakistan. It is also freighted with unresolved border disputes. To compound matters, all three states are now modernizing their nuclear forces and have expressed scant interest in any form of regional arms control. These issues and developments constitute the basis of this special section, which explores the problems and prospects of nuclear crisis stability in the region.  相似文献   
290.
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