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291.
讨论了维恩位移定律2种表述之间的关系,并与麦克斯韦分子分布函数的峰值相关量进行对比,说明原始的维恩表述是由实验决定的.并对2种表述的物理意义作了阐述.  相似文献   
292.
液体火箭发动机尾喷焰红外辐射特性   总被引:5,自引:0,他引:5       下载免费PDF全文
对液体火箭尾部喷焰红外辐射特性进行了仿真计算。利用所扩展建立的液体火箭发动机尾喷焰红外辐射组分的谱带参数数据库和尾喷焰流场数值仿真结果对辐射传输方程进行了数值求解,得到不同观测条件下的光谱辐射亮度。通过与实测数据对比,表明计算方法可行,结果合理。  相似文献   
293.
针对防化部(分)队应用放射源与含源装备仪器过程中产生大量废放射源的问题,根据国家和军队相关法规和标准,提出关于废放射源分类、收集、包装、运输、建库、储存和最终处置的贴近部队实际的处置方法要求.  相似文献   
294.
介绍了目前国外在核现场处理方面的技术途径以及采用的放射性去污和治理方法,分析了这些方法的优点和效果,并提出了适合中国国情的治理技术。  相似文献   
295.
结合核电站火灾危险的特殊性,阐述了核电站常规岛中网控楼、蓄电池室、汽轮机厂房、电缆隧道、输变电变压器等建筑的火灾自动报警系统设备的特殊配置及选用特点,以发挥火灾自动报警系统的监控作用。  相似文献   
296.
为提高电磁注入法的应用频带范围,提出基于定向耦合原理的电磁注入方法,并以某天线及其射频前端构成的互连系统为试验对象,利用单定向耦合器作为注入装置进行了辐照和注入试验,试验证明该注入方法能够准确替代连续波辐照效应试验.进而,理论分析耦合装置的特性并对该装置进行改进,提高其工程实用性.最后,设计耦合装置的指标并计算了对应的散射矩阵,制作完成注入装置的样机.结果表明:耦合装置监测端电压与等效源之间的关系会受到受试设备状态的影响.将两单定向耦合器级联作为注入装置,并以监测端的功率作为等效依据,可保证监测结果在高频时不受线缆上驻波的影响,提高试验的准确性.  相似文献   
297.
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   
298.
Ian Bellany, an Emeritus Professor of Politics at Lancaster University, died in July 2011 at the age of 70, after a long and painful struggle with myelofibrosis, a rare and invariably terminal blood cancer. Between early 2009 and August 2010, under contract to Hurst & Co., he worked intermittently on a book about nuclear terrorism, which he provisionally entitled Before the Storm. The editor and I are grateful to Michael Dwyer at Hurst & Co. for releasing the draft. What is published here is an edited version of that draft. It may seem presumptuous to speak for Ian, but I am sure he would also have liked to thank the doctors and nurses of the NHS Morecambe Bay Universities Hospital Trust, whose skill, knowledge, and flair for improvisation kept him alive and writing for much longer than anyone expected. Alastair Bellany, Rutgers University, New Jersey, USA.
In the past, terrorists have tended to eschew acts of extreme violence for fear of alienating those whom they wish to persuade and attract to their cause. The first to discard this philosophy was the Aum group in Japan, which sought to use anthrax and acquire a nuclear weapon. Since then, attitudes have changed, spurred on by the impact on public perception of the successful Al Qaeda 9/11 attack on New York and Washington. By crossing the line between moderation and extreme violence, terrorist groups retain one valuable capability: they are much less easily deterred and have few inhibitions. This article considers the three nuclear options open to terrorists – produce a radiological contaminant bomb; build a nuclear bomb; or steal or get given a nuclear device. It examines the possibilities and probabilities of each option and considers how the implementation of the Nuclear Non-proliferation Treaty (NPT) provisions might impose some constraints on terrorists’ nuclear ambitions. By examining the doubtful nuclear security practices of different states and providing statistical evidence of an increase in levels of international terrorist violence, this article points to determined terrorists in time acquiring the means to acquire one or other variants of a nuclear weapon. It concludes that it is not a matter of “if” but “when.”  相似文献   
299.
The idea of ‘clean’ bombs, nuclear weapons with a reduced amount of radioactive fallout resulting from their fission part, has met much ridicule since its public inauguration in 1956. Many scholars have regarded the bombs as a propaganda tool, stopping short of analyzing their role in the transformative phase of US nuclear strategy in the 1950s. This paper reexamines the clean bomb episode through 1958, shedding light upon the dynamic relationship between the development of nuclear weapons technology and the evolution of nuclear strategy from massive retaliation to flexible response. It also discusses the mechanism and momentum of nuclear weapons technology innovation until the US suspended nuclear testing in late 1958.  相似文献   
300.
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