全文获取类型
收费全文 | 514篇 |
免费 | 14篇 |
国内免费 | 1篇 |
专业分类
教育 | 319篇 |
科学研究 | 129篇 |
各国文化 | 4篇 |
体育 | 29篇 |
综合类 | 4篇 |
文化理论 | 5篇 |
信息传播 | 39篇 |
出版年
2023年 | 9篇 |
2022年 | 10篇 |
2021年 | 22篇 |
2020年 | 11篇 |
2019年 | 30篇 |
2018年 | 30篇 |
2017年 | 43篇 |
2016年 | 23篇 |
2015年 | 22篇 |
2014年 | 33篇 |
2013年 | 63篇 |
2012年 | 37篇 |
2011年 | 20篇 |
2010年 | 26篇 |
2009年 | 22篇 |
2008年 | 25篇 |
2007年 | 14篇 |
2006年 | 9篇 |
2005年 | 11篇 |
2004年 | 10篇 |
2003年 | 9篇 |
2002年 | 11篇 |
2001年 | 6篇 |
2000年 | 7篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1970年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有529条查询结果,搜索用时 15 毫秒
61.
The optimization of cultural conditions for β-glucanase production byBacillus subtilis ZJF-1A5 was investigated in flask trials. Temperature had great effect on β-glucanase production which maximized at optimal
temperature of 37°C and decreased significantly when temperature was over 37°C. Charge quantity affected β-glucanase production
significantly. Adding oxygen vector N-dodecane or acetic ether benefited β-glucanase production, but it depended on the concentration
and charge quantity. The results of fractional factorial design showed that age and size of inoculum and shaking speed were
the key factors affecting β-glucanase production and the cultivation time span to reach the highest β-glucanase activity.
The optimal cultural conditions for β-glucanase production obtained with CCD were as follows: inoculum age and size (16 h,
3.82% (v/v)), shaking speed 210 r/min, charge quantity of 30 mL in 250 mL flask and initial pH 7.0, cultured at 37°C for 50
h. Repeated experimental results accorded with those predicted by a second-order polynomial model. The amount of β-glucanase,
α-amylase and neutral protease produced byB subtilis ZJF-1A5 was associated partially with cell growth. Those three enzymes' activities increased following the cell growth and
increased significantly when cells entered the stationary phase.
Project (No. B0608) supported by the National Natural Science Foundation of China and a grant (2001121B25) from Hangzhou Science
and Technology Development Project of Zhejiang Province, China 相似文献
62.
63.
64.
Hasse,Cathrine (2015) An anthropology of learning. Springer (Berlin) isbn 978‐94‐017‐9605‐7 320 pp £90 (ebook £72) http://www.springer.com/us/book/9789401796057# 下载免费PDF全文
Mohammad Ali Salmani Nodoushan 《British journal of educational technology : journal of the Council for Educational Technology》2015,46(6):E30-E31
This book combines cultural models with practice‐based learning to develop a new theory of cultural learning. Drawing on insights from anthropology, it argues how collective and social cultures can emerge from an “engaged” learning process. The book opens a new window on human learning; however, you will probably find only parts of it of some interest or use. Mohammad Ali Salmani Nodoushan 相似文献
65.
66.
67.
Huda Karajeh Mahmoud Maqableh Lama Rajab Hiba Mohammad Tahani Khatib Nabeel Al-Qirim Ali Tarhini 《Education and Information Technologies》2018,23(5):2073-2090
This study examined impact of a social media networks course on student use of SNSs performance. Moreover, it examined the associations among course design, course materials, learning experiences and a social media networks course. Survey instrument is used to examine the relationships in the proposed model. A total of 380 questionnaires have been collected from students at the University of Jordan who studied the social media networks course. A structural equation modelling approach based on AMOS 20.0 statistical software is used to study the causal relationships and test the hypotheses between the observed and latent constructs in the proposed research model. The analysis results revealed that course materials and learning experiences directly, positively and significantly impacted the social media networks course, which in turn had a significant impact on students’ use social networks sites performance. Course design, however, did not impact the social media networks course. Our findings have important implications as we demonstrated the validity of the joint two different models and provide information about impact of studying social media networks course on students’ academic performance. 相似文献
68.
The main goal of this study was to integrate gender and group effect into bridging strategy in order to assess the effect
of bridging analogy-based instruction on sophomore students’ misconceptions in Newton’s Third Law. Specifically, the authors
developed and benefited from anchoring analogy diagnostic test to merge the effect of group and gender into the strategy.
Newton’s third law misconception test, attitude scale toward Newton’s third law, and classroom observation checklists were
the other measuring tools utilized throughout this quasi-experimental study. The researchers also developed or used several
teaching/learning materials such as gender and group splitted concept diagrams, lesson plans, gender splitted frequency tables,
make sense scales, PowerPoint slides, flash cards, and demonstrations. The convenience sample of the study chosen from the
accessible population involved 308 students from two public universities. The results of multivariate analysis of covariance
indicated that the bridging strategy had a significant effect on students’ misconceptions in Newton’s third law whereas it
had no significant effect on students’ attitudes toward Newton’s third law. 相似文献
69.
Akhtar Ali Keith J. Topping Riaz H. Tariq 《美中教育评论》2010,7(5):66-77
This paper explores entrepreneurial attributes among the students of The Islamia University of Bahawalpur, a public sector Pakistani university. Multistage sampling was employed to maximize the representation. Five hundred and twenty one master's level students from thirty departments returned completed questionnaires. Three factors emerged: self efficacy, efficiency and commitment, and entrepreneurial inclinations. The majority of the students exhibited positive entrepreneurial attributes. However, there was no significant difference between negative and positive entrepreneurial attributes. There was no significant impact of demographic variables such as gender, parental income and profession on entrepreneurial attributes. Impact on practice and policy is discussed. 相似文献
70.
Devecioglu Yasemin Akdeniz Ali Riza 《美中教育评论》2010,7(8):95-101
It is very important to develop student teachers' skills and knowledge during the pre-service teacher education process. In this study, the effectiveness of the approach in which student teachers' gained skills of developing and using TGMs (teacher-guided materials) based on integration of technology on physics education in STMC-Ⅱ (Special Teaching Methods Course-Ⅱ) for pre-service physics teachers was evaluated. The study was conducted with 33 physics student teachers in KTU (Karadeniz Technical University). Student teachers were required to develop and present TGMs, which were based on principles of special teaching approaches and techniques and integration of technology through instruction. The data of the study were gained from semi-structured interviews conducted with 14 student teachers, observations of the lessons conducted by each student teacher and document analysis of the student teachers' diaries collected during the term. The student teachers stated that STMC-11 was a very helpful experience to gain teaching skills. It is believed that all these activities, which are designed and performed in the classroom by student teachers during STMC-Ⅱ course, will not only prepare them for their teaching but also help them gain basic experiences that they will need in their future career. At the end of the process, it is concluded that all the student teachers gained nearly the whole defined aims--skills and knowledge of the STMC-Ⅱ. The implementation process should be organized very well to have advance of gaining many skills together. Key words: physics student teacher; STMC-Ⅱ; the skills of developing TGMs and integration of technology 相似文献