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   948篇
  免费   53篇
各国政治   60篇
工人农民   45篇
世界政治   60篇
外交国际关系   73篇
法律   395篇
中国政治   13篇
政治理论   343篇
综合类   12篇
  2023年   9篇
  2022年   5篇
  2021年   8篇
  2020年   25篇
  2019年   26篇
  2018年   31篇
  2017年   36篇
  2016年   50篇
  2015年   26篇
  2014年   39篇
  2013年   134篇
  2012年   36篇
  2011年   36篇
  2010年   31篇
  2009年   31篇
  2008年   22篇
  2007年   26篇
  2006年   41篇
  2005年   38篇
  2004年   30篇
  2003年   39篇
  2002年   34篇
  2001年   21篇
  2000年   17篇
  1999年   15篇
  1998年   16篇
  1997年   19篇
  1996年   4篇
  1995年   9篇
  1994年   6篇
  1993年   14篇
  1992年   4篇
  1991年   8篇
  1990年   12篇
  1989年   9篇
  1988年   8篇
  1987年   5篇
  1986年   7篇
  1985年   10篇
  1983年   5篇
  1981年   6篇
  1980年   7篇
  1979年   6篇
  1978年   7篇
  1977年   6篇
  1976年   3篇
  1975年   4篇
  1974年   4篇
  1973年   4篇
  1972年   3篇
排序方式: 共有1001条查询结果,搜索用时 15 毫秒
911.
912.
913.
914.
This article outlines the views of children and parents involved in family law disputes, about the need for and appropriateness of children's participation in decisions regarding residence and contact arrangements. Ninety parents and 47 children (ranging in age from 6 to 18 years) who had been through parental separation, were interviewed. Both parents and children had a range of views about the general appropriateness and fairness of children being involved, but the great majority, particularly of parents, thought that children should have a say in these matters. Core findings of the study include the considerable influence that older children had over the arrangements either in the aftermath of the separation or in making further changes over time, and the higher stated need of children who had experienced violence, abuse, or high levels of conflict to be heard than those in less problematic and noncontested matters. Parents involved in contested proceedings supported the participation of children at a younger age than those who were not. There was a reasonable degree of agreement between parents and children about the need for children to be acknowledged and the value of their views being heard in the decision‐making process. Parents, however, expressed concern about the pressure and manipulation that children can face and exert in this process, whereas children were generally more concerned about the fairness of the outcomes, and maintaining their relationships with their parents and siblings.  相似文献   
915.
This article seeks to briefly evaluate the context behind the development of regulations related to chromium pollution control in metal finishing industries. The available evidence suggests the possibility of elevation of the issue to the agenda for agency rule‐making, and subsequent implementation can occur even in the absence of focusing events. Based on historical evidence, this article illustrates that gradual accumulation of knowledge of harmful effects of chromium over the period of decades has been instrumental in the formulation and implementation of standards and guidelines to regulate chromium in the environment under major statutes such as the Clean Air Act, the Clean Water Act, the Safe Drinking Water Act, and so on. The implementation of command and control regulations has resulted in appreciable reduction of chromium released into the environment, thereby minimizing the impact on human health and the environment. However, achieving full compliance from metal finishing industries is still an illusion. There are examples of violations committed by industries. In response to this realization, policy evolution in the chromium pollution control domain has occurred in two directions: (1) gradual replacement of existing standards with more stringent standards and guidelines and (2) emphasis on multimedia, voluntary, and participatory approaches to improve compliance. But the results from the latter are not as dramatic as previously envisioned. Borrowing from the experience of the Common Sense Initiative (CSI), this article argues that consensus‐based, multistakeholder collaboration can be a policy development tool.  相似文献   
916.
917.
Wiki “communities” based on the open access ideology allow any visitor to easily add, remove or edit content. However, there are a slew of ethics and policy challenges inherent in their use. Open source software developers are faced with the dilemma of openly sharing their intellectual property and prevent others from claiming proprietary rights from the code they freely shared to the public? Intellectual Property rights licensing, ironically, is the route by which open software developers have chosen to regulate their free code in cyberspace. Open source code is generally free on the surface; but in reality, it comes with obligations which are enforceable by law. Aside from the potential liability for intellectual property infringement, the use of open software raises competition law and tort liability issues. The European Union has developed the European Public License which is written in conformity with the copyright, product liability and consumer protection laws of the 27 member states. The EU Commission has also proposed a new Directive which will extend the principles of consumer protection rules to cover licensing agreements of products like software. This paper will address the various legal issues that may arise in open source community sharing.  相似文献   
918.
Reliability of a two-dimensional footprint measurement approach   总被引:1,自引:0,他引:1  
Although footprint evidence can be taken from the scene of a crime, the science underpinning such measurement in forensic science has not been fully explored.A literature search revealed various measuring approaches, all of which demonstrated either little or no measurement rigour in terms of reliability. The aim of this study was to apply a robust measurement approach for testing the reliability of two-dimensional footprint impressions.Three dynamic and three static footprints were taken from the right foot of thirty female and thirty one male volunteers using the ‘Inkless Shoeprint Kit’. The images were digitised. Lengths, widths and angles were measured using a selection of currently employed methods.An investigation of the reliability of the chosen measuring method suggested high intra-rater agreement: for example, the length measurement suggested an intraclass correlation coefficient (ICC) 0.99, 95% Confidence Interval (CI) ? 0.28 to 0.01, standard error of measurement (SEM) 0.07, Limits of Agreement (LOA) ? 0.91 to 0.65.Inter-rater reliability between three operators was also high: SEM ranged from 0.05 mm to 0.07 mm, ICC 0.99.Our study has established a reliable two-dimensional measuring technique that could be used for footprint comparison in further research.  相似文献   
919.
Abstract: Criminal acts such as an attack utilizing a radiological dispersal device (RDD or dirty bomb), the manufacture of such a device, or the illicit trafficking of radioactive materials would warrant a criminal investigation. This could involve the collection, transportation, and analysis of radiologically contaminated trace evidence. But are law enforcement agencies and forensic scientists capable of dealing with this? This research investigates the decontamination efficacy of two decontamination techniques (chemical and physical) designed for the removal of radiological material from documents of forensic importance. The impact that these procedures have on the development of latent fingermarks and the forensic analysis of the inks on these documents is also studied. It was found that slight changes in the color and chemical composition of a variety of document inks and a destruction of fingermark ridges occurred after chemical decontamination. Physical decontamination had no impact on these parameters.  相似文献   
920.
Abstract:  A clandestine chemist was observed producing heroin from crude morphine utilizing a solution of sodium hypochlorite during the process. Numerous chlorinated opium alkaloid derivatives were created when the morphine acetylation reaction was quenched and neutralized with a solution of sodium hypochlorite and ammonium hydroxide. Four of these compounds, 1-chloroheroin, 1-chloroacetylcodeine, 1-chloro-O6-monoacetylmorphine, and 2'-chloropapaverine, were characterized via preparative isolation, gas chromatography/mass spectrometry, nuclear magnetic resonance spectroscopy, and independent synthesis. These chlorinated derivatives were formed via electrophilic aromatic substitution with free chlorine during the illicit process. Although no illicit heroin exhibits containing these compounds have been observed in seizures to date, mass spectral data are provided for several of these compounds for their identification should they be seen within future seizures of illicit heroin.  相似文献   
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