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   485篇
  免费   8篇
  国内免费   12篇
教育   375篇
科学研究   81篇
体育   18篇
综合类   17篇
信息传播   14篇
  2023年   1篇
  2022年   3篇
  2021年   7篇
  2020年   6篇
  2019年   4篇
  2018年   5篇
  2017年   9篇
  2016年   6篇
  2015年   12篇
  2014年   30篇
  2013年   46篇
  2012年   27篇
  2011年   36篇
  2010年   39篇
  2009年   26篇
  2008年   27篇
  2007年   35篇
  2006年   46篇
  2005年   30篇
  2004年   27篇
  2003年   26篇
  2002年   15篇
  2001年   13篇
  2000年   11篇
  1999年   3篇
  1998年   5篇
  1997年   2篇
  1996年   2篇
  1995年   3篇
  1991年   1篇
  1989年   1篇
  1985年   1篇
排序方式: 共有505条查询结果,搜索用时 31 毫秒
61.
INTRODUCTION Turbulent gas-particle flows are frequently found in natural phenomena and industrial processes.Cases of cylinders in cross flows with particles occur in heat exchange equipment,including the convective zone of a fluidized-bed combustor,and in the primary superheaters,reheaters,and economizers of coal-fired boilers.Coherent structures often occur in the above-mentioned gas-particle flow,and have great effect on such different systems,while some features of tur-bulent multiphas…  相似文献   
62.
轭式修辞格(Zeugma)是一种用法较为独特的修辞手法。由于其使用不如其它的修辞方法那么普遍,所以很少有人去注意它。本文将对这一修辞格的分类及结构作一初步探讨。  相似文献   
63.
在英语中 ,有一些句子形式上是肯定的 ,但却表达一种否定的意义。所以在阅读理解英语文章时要注意语言环境 ,注意那些形肯意否的表达方式 ,切不可望文生义。  相似文献   
64.
Bharath Sriraman 《Interchange》2006,37(1-2):151-178
This paper explores the wide range of mathematics content and processes that arise in the secondary classroom via the use of unusual counting problems. A universal pedagogical goal of mathematics teachers is to convey a sense of unity among seemingly diverse topics within mathematics. Such a goal can be accomplished if we could conduct classroom discourse that conveys the Lakatosian (thought-experimental) view of mathematics as that of continual conjecture-proof-refutation which involves rich mathematizing experiences. I present a pathway towards this pedagogical goal by presenting student insights into an unusual counting problem and by using these outcomes to construct ideal mathematical possibilities (content and process) for discourse. In particular, I re-construct the quasi-empirical approaches of six!4-year old students’ attempts to solve this unusual counting problem and present the possibilities for mathematizing during classroom discourse in the imaginative spirit of Imre Lakatos. The pedagogical implications for the teaching and learning of mathematics in the secondary classroom and in mathematics teacher education are discussed.  相似文献   
65.
Despite striking similarities, the adoption and implementation of policy shifts regarding higher education governance vary considerably across the globe, suggesting a mixed picture of diversification and isomorphism both within and across national higher education systems. By unpacking one particular structural reform process, this paper focuses on mergers as both a governance tool and a governance result in higher education. The paper analyzes the strategic decisions taken by Norwegian higher education institutions during 2014 in the light of a proposed national reform to merge institutions in order to enhance quality in higher education. The empirical basis of the paper consists of analyses of the commissioned self-evaluations of the higher education institutions, and the strategic choices and dilemmas they expressed. The process can be seen as organizational engineering in the sense that it emerges from the self-evaluation process, but is also subject to governancing on the part of the ministry.  相似文献   
66.
运用G98W,采用Lan12dz基组,对茂金属配合物[eta^5-C5H4Si2Me5)Mo-Br(CO)3]进行从头算研究,探讨配合物结构单元的稳定性,分子轨道能量,原子净电荷布局规律,以及一些前沿分子轨道的组成特征等,结果表明,标题配合物结构在能量上是稳定的,作为结构单元而存在,为茂金属配合物的合成,分子组装分析提供参考。  相似文献   
67.
In civil engineering, the nonlinear dynamic instability of structures occurs at a bifurcation point or a limit point. The instability at a bifurcation point can be analyzed with the theory of nonlinear dynamics, and that at a limit point can be discussed with the theory of elastoplasticity. In this paper, the nonlinear dynamic instability of structures was treated with mathematical and mechanical theories.The research methods for the problems of structural nonlinear dynamic stability were discussed first, and then the criterion of stability or instability of structures, the method to obtain the bifurcation point and the limit point, and the formulae of the directions of the branch solutions at a bifurcation point were elucidated. These methods can be applied to the problems of nonlinear dynamic instability of structures such as reticulated shells, space grid structures, and so on.  相似文献   
68.
写作是大学英语教学的难点之一,也是四、六级考试的重点之一。笔者认为在考试中,书写工整漂亮、词汇标新立异、造句与众不同以及布局独树一帜可以帮助考生提高四、六级的作文分数。  相似文献   
69.
This paper reports on findings from a three-year ethnographic study of 24 young people in northern England who were classified as not in education, employment or training (NEET), or at risk of becoming so. Drawing on conceptions of opportunity structure and educational marginality, the paper discusses the processes leading to young people becoming NEET after leaving school. It presents findings concerning the family backgrounds, school experiences, and educational attainment of participants, and traces their initial post-16 destinations and their pathways to NEET status. Although most participants did not become NEET immediately after leaving school, restricted labour market opportunities and a lack of high-quality education and training for middle- and low-attaining young people exacerbated social and educational disadvantage. Over time, participants became increasingly restricted to marginal forms of learning. The paper argues that a focus on opportunity structures provides a powerful way of understanding these processes, and that alongside sustained NEET status, educational marginality should be of equal concern to policy makers.  相似文献   
70.
检察制度的改革是我国司法改革的重要组成部分。检察制度的改革必须以检察机关的结构与功能为基础.通过技术系统、管理系统与制度系统的结构分析,以及社会控制、保证规范实施和促进纠纷解决的功能分析,以期人们能把握检察机关的结构与功能,从而对其改革有所裨益。  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