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   2596篇
  免费   77篇
  国内免费   69篇
电工技术   22篇
综合类   1035篇
化学工业   88篇
金属工艺   34篇
机械仪表   51篇
建筑科学   223篇
矿业工程   12篇
能源动力   17篇
轻工业   81篇
水利工程   27篇
石油天然气   5篇
武器工业   3篇
无线电   205篇
一般工业技术   113篇
冶金工业   431篇
原子能技术   10篇
自动化技术   385篇
  2024年   8篇
  2023年   24篇
  2022年   35篇
  2021年   41篇
  2020年   46篇
  2019年   37篇
  2018年   24篇
  2017年   33篇
  2016年   60篇
  2015年   72篇
  2014年   140篇
  2013年   146篇
  2012年   173篇
  2011年   217篇
  2010年   195篇
  2009年   216篇
  2008年   195篇
  2007年   196篇
  2006年   174篇
  2005年   143篇
  2004年   112篇
  2003年   96篇
  2002年   82篇
  2001年   57篇
  2000年   35篇
  1999年   22篇
  1998年   16篇
  1997年   11篇
  1996年   9篇
  1995年   9篇
  1994年   10篇
  1993年   6篇
  1992年   5篇
  1991年   5篇
  1990年   8篇
  1982年   4篇
  1978年   3篇
  1975年   3篇
  1974年   3篇
  1965年   4篇
  1964年   5篇
  1963年   4篇
  1962年   2篇
  1961年   3篇
  1959年   4篇
  1958年   2篇
  1957年   8篇
  1956年   5篇
  1955年   5篇
  1954年   6篇
排序方式: 共有2742条查询结果,搜索用时 31 毫秒
1.
Numerous conceptual difficulties and misconceptions have been reported in the science and chemistry education literature about electrochemistry concepts such as electrolytes, redox equations, and about electrochemical (galvanic and electrolytic) cells. Other studies have considered teaching approaches aimed at improving learning and at overcoming misconceptions. This paper reviews these studies and considers strategies and approaches for the effective teaching of electrochemistry. Then, the review focuses on problem solving in equilibrium electrochemistry, especially problems involving the Nernst equation. The main findings of four studies with Greek university chemistry students, dealing with: (i) algorithmic problem‐solving ability; (ii) practice on problem solving; (iii) the effect of the format of a problem; and (iv) the construction and evaluation of a website devoted to electrochemistry problem solving, are reported.  相似文献   
2.
The primary goal of this study is to create and test a lecture‐capture system that can rearrange visual elements while recording is still taking place, in such a way that student performance can be positively influenced. The system we have devised is capable of integrating and rearranging multimedia sources, including learning content, the instructor and students' images, into lecture videos that are embedded in a website for students to review after school. The present study employed a two‐group experimental design, with 153 participants (145 females and 8 males) making up an experimental group in which lecture courses were recorded using the new lecture‐capture system, and 149 participants (140 females and 9 males) forming a control group whose lectures were recorded by traditional means. All participants were in the freshman college and studying Introduction to Computer and Information Science in one of six classes, and were randomly assigned to one of the two groups. The participants' midterm examination and final examination scores were collected as indicators of their academic performance, with their mathematics entrance scores used as a pre‐test. The findings obtained from analysis of covariance (ANCOVA) suggest that appropriate rearrangement of visual elements in lecture videos can significantly impact students' learning performance.  相似文献   
3.
Revising deductive knowledge and stereotypical knowledge in a student model   总被引:1,自引:1,他引:0  
A user/student model must be revised when new information about the user/student is obtained. But a sophisticated user/student model is a complex structure that contains different types of knowledge. Different techniques may be needed for revising different types of knowledge. This paper presents a student model maintenance system (SMMS) which deals with revision of two important types of knowledge in student models: deductive knowledge and stereotypical knowledge. In the SMMS, deductive knowledge is represented by justified beliefs. Its revision is accomplished by a combination of techniques involving reason maintenance and formal diagnosis. Stereotypical knowledge is represented in the Default Package Network (DPN). The DPN is a knowledge partitioning hierarchy in which each node contains concepts in a sub-domain. Revision of stereotypical knowledge is realized by propagating new information through the DPN to change default packages (stereotypes) of the nodes in the DPN. A revision of deductive knowledge may trigger a revision of stereotypical knowledge, which results in a desirable student model in which the two types of knowledge exist harmoniously.  相似文献   
4.
Stereotype threat research has demonstrated that stereotypes can harm student performance in the face of public evaluation by peers or an experimenter. The current study examined whether stereotypes can also threaten in private settings. Female students completed a math test in 3-person groups, which consisted of either 2 other women (same gender) or 2 men (minority). In addition, students either believed their performance would be broadcasted to their peers (public) or not (private). Results revealed that minority students performed worse than same-gender students in both public and private environments. This finding supports the concept of threatening intellectual environments and shows how far reaching the effects of stereotypes can be. The authors discuss these findings in relation to research on tokenism and to stereotype threat and its educational implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
What do health care practitioners need to know about providing adequate care for depressed minority women? This article examined the prevalence of depressive symptoms and clinical depression in ethnic minorities, the extent to which current health service utilization is congruent with needs, and the effectiveness of treatments provided to ethnic minorities in the primary care setting. The impact of ethnic minority women's sociocultural context on symptom expression and help-seeking behavior is also discussed. Finally, the clinical implications for accurate assessment and treatment of ethnic minority women by both medical and mental health practitioners working in the primary care sector are addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
结合自身的学习、工作经历,与研究生畅谈如何学会“做人、做事、做学问”。  相似文献   
7.
The relationship between teachers' judgments versus actual performance on curriculum-based measures in reading was examined. A total of 30 regular education teachers were asked to predict the oral reading fluency score of students along with a rating scale of reading subskills. Correlations between teacher judgment measures and student performance found that teachers were accurate reporters of student performance levels in reading. However, some questions were raised whether teachers were accurate at predicting the actual level of student oral reading fluency when effect sizes were used to compare teacher judgment and actual student performance. Recommendations for continued research in understanding the parameters of the accuracy of teacher judgment are made. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
8.
论大学生体育参与动机的培养   总被引:1,自引:0,他引:1  
大学生具有良好的参与动机是实现体育教学目标的一个重要前提条件。本文通过对体育参与动机内涵及影响体育参与动机的心理因素的分析,提出了大学体育教学中如何培养大学生正确的体育参与动机的一些想法,以供广大体育工作者参考。  相似文献   
9.
介绍了一种非接触式用于测量少子寿命的微波反射法,并与通常的光电导衰退法进行了比较。  相似文献   
10.
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