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   105篇
  免费   4篇
教育   75篇
科学研究   14篇
体育   6篇
文化理论   1篇
信息传播   13篇
  2023年   1篇
  2020年   3篇
  2019年   1篇
  2018年   5篇
  2017年   2篇
  2016年   3篇
  2015年   5篇
  2014年   5篇
  2013年   26篇
  2012年   2篇
  2011年   5篇
  2010年   6篇
  2009年   1篇
  2008年   2篇
  2007年   3篇
  2002年   3篇
  2001年   6篇
  2000年   1篇
  1999年   2篇
  1998年   1篇
  1997年   2篇
  1996年   2篇
  1992年   3篇
  1991年   1篇
  1990年   1篇
  1989年   4篇
  1988年   1篇
  1986年   1篇
  1985年   1篇
  1984年   1篇
  1977年   1篇
  1974年   1篇
  1930年   2篇
  1866年   3篇
  1835年   1篇
  1828年   1篇
排序方式: 共有109条查询结果,搜索用时 8 毫秒
71.
Four experiments examined 3- and 4-year-olds' ability to communicate about containment and proximity relations. One hundred twenty-eight children either described where a miniature mouse was hiding in a dollhouse or they searched for the mouse after the experimenter described where it was hiding. The mouse was always hidden with a small landmark that was either in or next to a large landmark. When describing where the mouse was hiding, children were more likely to successfully disambiguate the small landmark when it was in the large landmark (e.g., under the plant in the dresser) than when it was next to the large landmark (e.g., under the plant next to the dresser). When searching for the mouse, 3-year-olds were faster to initiate their searches when the small landmark was in the large landmark than when it was next to the large landmark. Together, these results suggest that there are informational biases in young children's spatial communication.  相似文献   
72.
73.
74.
The purpose of this research was to better understand the variety of student and faculty global learning and development programs by member institutions of the Council for Christian Colleges & Universities (CCCU), and what motivated the creation of these types of programs. Although various forms of global engagement programming were examined, the scope of the study primarily focused on mutually beneficial long-term programs that had been designed to reduce poverty, alleviate social problems, and promote other forms of social progress. Data were collected over a seven-month period in 2014 from interviews with 19 faculty and global learning and development leaders who represented 13 CCCU member institutions. The findings documented a wide variety of CCCU-sponsored global programs and partnerships, the motives and faith foundations for these global initiatives, and various levels of institutional support for global programming.  相似文献   
75.
Electroosmotic flow was studied in thin film microchannels with silicon dioxide and silicon nitride sidewalls formed using plasma-enhanced chemical vapor deposition (PECVD). A sacrificial etching process was employed for channel fabrication allowing for cross-sections with heights of 3 μm, ranging from 2 μm to 50 μm in width. Flow rates were measured for single channels and multichannel electroosmotic pump structures for pH levels ranging from 2.6 to 8.3, and zeta potentials were calculated for both silicon dioxide and silicon nitride surfaces. Flow rates as high as 0.086 μL∕min were measured for nitride multichannel pumps at applied electric fields of 300 V∕mm. The surface characteristics of PECVD nitride were analyzed and compared to more well-known oxide surfaces to determine the density of amine sites compared to silanol sites.  相似文献   
76.
77.
Research in Higher Education - In 2010, the Obama Administration proposed new regulations designed to hold institutions of higher education (IHEs) accountable for student outcomes. I examine the...  相似文献   
78.
79.
This is a report on the International Statistical Institute's Round Table Conference, 23rd-27th July, 1988, held in Hungary, and convened by Anne Hawkins.  相似文献   
80.
We describe the integration of an actively controlled programmable microfluidic sample processor with on-chip optical fluorescence detection to create a single, hybrid sensor system. An array of lifting gate microvalves (automaton) is fabricated with soft lithography, which is reconfigurably joined to a liquid-core, anti-resonant reflecting optical waveguide (ARROW) silicon chip fabricated with conventional microfabrication. In the automaton, various sample handling steps such as mixing, transporting, splitting, isolating, and storing are achieved rapidly and precisely to detect viral nucleic acid targets, while the optofluidic chip provides single particle detection sensitivity using integrated optics. Specifically, an assay for detection of viral nucleic acid targets is implemented. Labeled target nucleic acids are first captured and isolated on magnetic microbeads in the automaton, followed by optical detection of single beads on the ARROW chip. The combination of automated microfluidic sample preparation and highly sensitive optical detection opens possibilities for portable instruments for point-of-use analysis of minute, low concentration biological samples.  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