排序方式: 共有55条查询结果,搜索用时 15 毫秒
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采用超声焊接铝合金箔材的工艺修复处理表面腐蚀受损的2A12CZ基体,并利用Quanta200型环境扫描电子显微镜分析了截面形貌及箔材与基体之间界面表面断口的微观形貌。结果表明:从截面来看,箔材与基体之间大部分发生了焊合,界面分界线大部分消失;从机械脱开的界面断口来看,其表面微观形貌表现为鳞片状及韧窝状的典型金属型断口形貌。这说明在给定条件下,焊接部位大部分呈冶金结合。最后对铝台金箔材与铝合金基体之间超声焊接机理进行了探讨。 相似文献
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Stephen I. Schwartz 《The Nonproliferation Review》2013,20(1):1-2
The Nonproliferation Review (NPR) recently interviewed Ambassador Sergio de Queiroz Duarte of Brazil, who presided over the 2005 Seventh Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Ambassador Duarte discussed his views on the outcome of the conference and the future of the treaty. He provided NPR with valuable insights into the outcome of the conference and also shared his thoughts on some of the most pressing issues confronting the NPT today, including the Middle East, nuclear terrorism, elimination of the threat of highly enriched uranium in the civilian nuclear sector, proposals to limit access to the nuclear fuel cycle, nuclear disarmament, and negative security assurances. Blaming the failed conference on a general lack of political commitment among states parties and their unwillingness to negotiate common solutions, Ambassador Duarte stressed that “the conference should face squarely its own failure without my attempting to disguise or sugarcoat the deep differences of view, which must be resolved with courage and determination by the states parties if they want the treaty to remain effective.”?He emphasized that if states fail to act on their overriding interest in upholding the NPT, especially if states parties continue to ignore or disregard their nonproliferation and nuclear disarmament obligations, some states might come to believe that their security interests are no longer served by the treaty. The future prospects of the NPT would then “look dire indeed.” 相似文献
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Justin V. Hastings 《The Nonproliferation Review》2013,20(3):429-450
This article uses a geographic approach to examine one aspect of the nuclear black market: the coordinators who bring buyers and sellers together, and transport goods between them. The most important factor in determining the geographical structure of a proliferation network is the network coordinator's access (or lack thereof) to unique state resources. Coordinators with access to state resources and prerogatives can avoid embedding themselves in hostile countries or relying on commercial infrastructure, often leading to territorially diffuse logistical networks. Coordinators without such access are forced to rely on commercial infrastructure and favorable local political, economic, and social conditions, often resulting in territorially centralized logistical networks. This is illustrated through case studies of Abdul Qadeer Khan's supply networks to Pakistan, Libya, and Iran. The article concludes with some observations about the implications of a geographical approach for understanding nuclear proliferation networks. 相似文献
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