首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   893篇
  免费   21篇
  2021年   14篇
  2019年   29篇
  2018年   19篇
  2017年   20篇
  2016年   20篇
  2015年   20篇
  2014年   11篇
  2013年   166篇
  2011年   8篇
  2009年   9篇
  2008年   8篇
  2007年   11篇
  2006年   11篇
  2005年   15篇
  2004年   16篇
  2003年   10篇
  2002年   8篇
  2000年   14篇
  1999年   10篇
  1998年   12篇
  1997年   24篇
  1996年   19篇
  1994年   18篇
  1993年   7篇
  1992年   11篇
  1991年   22篇
  1990年   12篇
  1989年   19篇
  1988年   12篇
  1987年   21篇
  1986年   16篇
  1985年   16篇
  1984年   12篇
  1983年   15篇
  1982年   13篇
  1981年   13篇
  1980年   16篇
  1979年   17篇
  1978年   14篇
  1977年   15篇
  1976年   14篇
  1975年   12篇
  1974年   18篇
  1973年   18篇
  1972年   15篇
  1971年   19篇
  1970年   9篇
  1969年   11篇
  1968年   10篇
  1967年   8篇
排序方式: 共有914条查询结果,搜索用时 15 毫秒
891.
ABSTRACT

The dangers and risks of employing a Conventional Prompt Global Strike (CPGS) capability greatly exceed the benefits. More suitable, if less prompt, alternatives exist to deal with fleeting targets. Even a niche CPGS capability—consisting of approximately twenty systems—carries risks, to say nothing of proposals to develop hundreds or more. Most dangerously, CPGS could stir the pre-emption pot, particularly vis-à-vis states that correctly perceive to be within the gunsights of US CPGS weapons; other states, too, may feel emboldened to emulate this US precedent and undertake their own form of prompt, long-range strike capability. Compressed circumstances surrounding such a scenario could foster unwanted erratic behavior, including the misperception that the threatening missile carries a nuclear weapon. But the true Achilles's heel of the CPGS concept is the unprecedented demands it places on the intelligence community to provide decision makers with “exquisite” intelligence within an hour timeframe. Such compressed conditions leave decision makers with virtually no time to appraise the direct—and potentially unintended—consequences of their actions.  相似文献   
892.
Russian naval nuclear fuel and reactors pose both proliferation and environmental threats, ranging from the possible theft of highly enriched uranium fuel to the radioactive contamination of the environment, whether due to accident, neglect, or sabotage. Current conditions at Russian naval bases, together with a history of accidents and incidents involving Russia's nuclear fleet, make a convincing case for the large-scale assistance that the G8 is now providing to improve the safety and security of Russian naval reactors and fuel. However, virtually no data has been released to allow accurate, reliable, and independent analysis of reactor and fuel properties, risking misguided international efforts to assist in the areas of nuclear cleanup, nonproliferation, and security. This article identifies and assesses relevant properties and developments related to reactor and fuel design, provides a comprehensive presentation of Russian nuclear naval technologies, and examines technological trends in the context of proliferation and environmental security.  相似文献   
893.
In the aftermath of September 11, 2001 and Hurricane Katrina, the United States government has spent tens of billions of dollars to improve the nation's ability to respond to a natural disaster or terrorist attack, but the emphasis on immediate first response has left many long-term environmental, political, and technological challenges unaddressed. Although a dirty bomb attack is unlikely to yield the same amount of physical devastation and death as caused by Katrina or a nuclear weapon, the social, psychological, and economic impact would be enormous. At present, however, the United States lacks the technology necessary to decontaminate a large, densely populated urban area under time, political, and economic constraints. This article reviews past cleanup experiences and current decontamination capabilities to consider the long-term implications of a dirty bomb, identifies weaknesses in America's existing response capabilities, notes possible areas of political friction, and considers the implications of the failure to adequately prepare. Having the appropriate decontamination techniques established and long-term plans in place before an incident occurs will significantly improve the government's ability to protect public and environmental security, establish a viable decontamination strategy, allow residents to return to their homes, and get the local economy back on its feet.  相似文献   
894.
895.
The Biological Weapons Convention (BWC) regime currently suffers from a lack of effective compliance procedures. Because a legally binding compliance protocol to the BWC is not available, other measures are needed to stabilize the regime against the risk of violations of its rules. The Treaty on the Non-Proliferation of Nuclear Weapons, the Chemical Weapons Convention, and the experiences of UN inspection teams show that among the necessary components of effective compliance mechanisms are an intermediary level between bilateral consultations of states parties and involvement of the UN Security Council as well as independent assessment capabilities. This article suggests that the UN Secretary General could assume such an intermediary function and, using the authority contained in Article 99 of the UN Charter, could investigate not only alleged use of biological weapons but also alleged breaches of the BWC. A standing expert unit in the Department for Disarmament Affairs could provide the independent expertise necessary for such investigations. Such a compliance mechanism could provisionally help stabilize the BWC regime until a permanent compliance system can be agreed.  相似文献   
896.
Israel's exceptional status as a nonsignatory to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) has been an increasingly salient issue, particularly during the intense debate over universality in the 1995 NPT Review and Extension Conference, and again following the Indian and Pakistani tests in 1998. This analysis argues that despite these events, Israel's diplomatic position has not weakened significantly in the past decade. The factors that have led to this outcome include changes in the political and strategic environment, including the Iraqi and Iranian NPT violations, and Israeli engagement in different fora such as the Conference on Disarmament (CD) and the United Nations, and in bilateral strategic dialogues with key powers. This report examines whether Israel's exceptional status is likely to be maintained in the face of recent developments in Iran and the precedent set by the U.S.-India nuclear cooperation agreement.  相似文献   
897.
898.
THE NPT     
This article assesses the successes and failures of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) since its creation in 1968 by developing and applying a set of “metrics” to each of the NPT's substantive articles as well as to its withdrawal provisions. In light of this analysis, the article also puts forward some specific proposals for strengthening the NPT and its implementation, with a view to the debate and decisions at the upcoming 2010 NPT Review Conference. A concluding section turns explicitly to the 2010 NPT Review Conference and proposes pursuit of agreement on three NPT Action Plans: one for nonproliferation, one for peaceful uses, and one for nuclear disarmament. Combining vision and practicable steps, these Action Plans would set out a roadmap for action between the 2010 and the 2015 NPT Review Conferences. They could provide a foundation for substantive exchanges—in this case, on progress toward their implementation—during the preparations for the 2015 conference.  相似文献   
899.
900.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号