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   188篇
  免费   3篇
  国内免费   8篇
教育   141篇
科学研究   21篇
各国文化   1篇
体育   17篇
综合类   2篇
文化理论   1篇
信息传播   16篇
  2023年   1篇
  2022年   1篇
  2021年   2篇
  2020年   3篇
  2019年   6篇
  2018年   10篇
  2017年   4篇
  2016年   10篇
  2015年   3篇
  2014年   15篇
  2013年   33篇
  2012年   7篇
  2011年   11篇
  2010年   11篇
  2009年   6篇
  2008年   8篇
  2007年   7篇
  2006年   4篇
  2005年   10篇
  2004年   5篇
  2003年   3篇
  2002年   4篇
  2001年   5篇
  2000年   2篇
  1999年   3篇
  1998年   1篇
  1997年   3篇
  1994年   2篇
  1993年   1篇
  1991年   2篇
  1990年   1篇
  1989年   1篇
  1988年   2篇
  1986年   2篇
  1985年   5篇
  1983年   3篇
  1981年   1篇
  1979年   1篇
排序方式: 共有199条查询结果,搜索用时 31 毫秒
111.
112.
Book reviews     
The purpose of this study was to find out: (a) pupils' attitudes towards open-ended science investigations, and (b) the problems that pupils encounter when carrying out such investigations in groups. The study was conducted in a class of 39 primary 6 pupils of mixed ability who carried out four investigations. Data were based on pupils' responses on an attitude survey questionnaire, interviews, video tapes of pupils performing the investigations and field notes. The majority of the pupils liked conducting such investigations. Reasons for positive responses were that the pupils had the freedom to explore and devise their own procedures to find out things that they wanted to know about, they could work together and discuss with friends, the investigations were interesting and it was a valuable learning experience. Reasons for negative responses included the difficulty of coming up with good ideas to design the investigations, and group conflicts. The findings also indicate that group dynamics played an important role in influencing pupils' attitudes towards the investigations.  相似文献   
113.
The purpose of this study was to (a) find out the types of questions that pupils ask for open-ended science investigations, and (b) discuss how teachers can help pupils to identify problems and pose questions that are feasible for investigations. The study was conducted in a class of 39 primary 6 pupils of mixed ability. The pupils wrote down questions for two investigations that they would like to work on. The questions for the first investigation were generated individually, but those for the second investigation were posed in groups after the pupils were shown some examples of investigable questions. Among the questions that were posed individually, only 11.7% could be answered by performing hands-on investigations. Most of the questions asked were based on general knowledge and covered a wide range of topics. However, when questions were generated in groups after examples were shown, there was a significant increase in the number of questions that were amenable to science investigations (71.4%) but they related to fewer topics. A typology of investigable and non-investigable questions is proposed. Suggestions on how teachers can help pupils to pose problems and questions that are feasible for investigations are given.  相似文献   
114.
稠油油藏水驱采收率低,因其原油黏度高,不适合转化学驱,但转热采可大幅提高采收率。林樊家油田林东馆三段地质条件复杂,地层敏感性强,供液差,产能低,油稠,出砂严重,多年来采用了各种工艺措施,均未取得好的水驱开采效果。在分析低效水驱原因的基础上,论证了水驱转蒸汽热采可行性。开发实践表明,低效水驱稠油油藏通过转热采可大幅提高采收率,同时研究成果对同类油藏的开发具有重要指导意义。  相似文献   
115.
Abstract

We investigated the effects of an acute bout of exercise on serum soluble leptin receptor (sOB-R) concentrations. Eighteen male participants completed two different exercise sessions with intensities of 25% and 65% maximal aerobic capacity (VO2max). In addition to the energy expenditure during exercise sessions being measured, blood samples were collected before exercise, and immediately, at 24 h, and at 48 h post-exercise to analyse sOB-R, leptin and insulin levels. At 24 h post-exercise, sOB-R and leptin concentrations at the 65% VO2max were significantly different from those at the 25% VO2max. Leptin levels at 48 h post-exercise were also significantly lower for the 65% VO2max than for the 25% VO2max (P < 0.01). In the 65% VO2max session, the energy expenditure during exercise was significantly associated with leptin concentrations at 24 h and 48 h and sOB-R concentrations at 24 h post-exercise. However, no correlations were found between sOB-R and leptin at the three post-exercise time points. In conclusion, an acute bout of exercise with 920 kcal of output resulted in an increase in sOB-R levels at 24 h post-exercise. However, the changes in sOB-R levels due to an acute bout of exercise might not contribute to the delayed decrease observed for leptin.  相似文献   
116.
117.
This paper explores the concept of translocality, of being ‘simultaneously situated’ in more than one place, in the context of ‘distance’ education in the digital university. The author works with the concept of critical time to propose an additional term, transtemporality, to also recognise the multiple times and temporalities engaged and interwoven in digitally connected spaces of work and study. The paper draws on interview material from an institutional case study of expansion in digital education, paying particular attention to student locations in time and space, arguing that recognising the shifting time–space of the campus is essential to supporting and teaching growing numbers of distance and part-time students. The author proposes that, rather than digital connections being viewed as a form of ‘reaching out’ from the university campus to the wider world, the digital university might be considered, in its translocal and transtemporal form, as an opening up of the idea of the university; embodied and imagined through strong connections across multiple locations, times and temporalities.  相似文献   
118.
The link between motivation and success is well documented; however, there is still room to problematise motivation in regards to the individual and contextual levels. This study looks at motivation in relation to students studying undergraduate engineering courses at a Caribbean university and seeks to discover the factors that motivate them to study and the factors that keep them motivated. An online questionnaire was constructed using 19 Likert-type questions and 5 questions that allowed for open-ended qualitative responses. The findings reveal that participants tended to be motivated by the increased possibility of desired future careers and tended to stay motivated by a combination of goal-orientation and family support. It is recommended that departments, faculties and institutions deliberate on shared and contextually constructed understandings of why students choose to enrol in particular university courses.  相似文献   
119.
This is the result of a Survey of diagnostics laboratories in the Asia Pacific (APAC) region with perspectives on India, investigating the three key aspects that are central to the success of a laboratory: quality, cost and speed. This Survey provides a comparison in selected performance indicators in a large number of diagnostic laboratories in a broad range of countries in the APAC region. The Survey provides data on some key performance characteristics such as quality improvement activities, staff productivity and Turnaround Time (TAT). This Survey also demonstrates in India the common issues facing all the laboratories surveyed but also common solutions using a Quality Systems approach which involves Accreditation, customer responsiveness, greater use of IT, automation and Lean principles. Indian laboratories reported less automation and fewer laboratories have Laboratory Information Systems. The productivity by various measures in Indian laboratories was less than in other APAC laboratories. TAT was more commonly monitored in the Indian specimens though there were fewer laboratories compared with the APAC specimens where there were separate TATs for Short Turnaround Time and Routine specimens.  相似文献   
120.
伞形科植物染色体数目报告   总被引:2,自引:0,他引:2  
 Chromosome numbers are reported for 26 species and varieties of Umbelliferae which belong to 3 subfamilies and 19 genera in this paper.  Of these, 13 counts are new records and some problems about chromosome numbers of Umbelliferae are simplydiscussed.  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