全文获取类型
收费全文 | 797篇 |
免费 | 27篇 |
国内免费 | 1篇 |
专业分类
教育 | 528篇 |
科学研究 | 72篇 |
各国文化 | 21篇 |
体育 | 58篇 |
综合类 | 1篇 |
文化理论 | 16篇 |
信息传播 | 129篇 |
出版年
2023年 | 8篇 |
2022年 | 13篇 |
2021年 | 27篇 |
2020年 | 28篇 |
2019年 | 43篇 |
2018年 | 57篇 |
2017年 | 55篇 |
2016年 | 65篇 |
2015年 | 31篇 |
2014年 | 44篇 |
2013年 | 149篇 |
2012年 | 39篇 |
2011年 | 29篇 |
2010年 | 27篇 |
2009年 | 18篇 |
2008年 | 20篇 |
2007年 | 20篇 |
2006年 | 24篇 |
2005年 | 21篇 |
2004年 | 17篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 4篇 |
1999年 | 10篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 6篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1976年 | 1篇 |
排序方式: 共有825条查询结果,搜索用时 0 毫秒
821.
Lavinia de Ferri Pier Paolo Lottici Andrea Lorenzi Angelo Montenero Emma Salvioli-Mariani 《Journal of Cultural Heritage》2011,12(4):356
The growing interest in the conservation of historic buildings encourages the development of water-repellent materials and methodologies to consolidate and/or protect stones. Recently, particular attention was devoted to composites of inorganic oxides nanoparticles and hybrid siloxane or silicone polymers. Here we present a study on the water repellence of a thin protective coating obtained through sol-gel process starting from Glymo and Dynasylan 40®, and loading the silicate matrix with nano-sized silica particles (Aeroxide LE1® -Degussa-Evonik). The coatings were applied to limestone, sandstone and granite samples. The silica nanoparticles have been characterized by XRD, the siloxane matrix through micro-Raman spectroscopy, while the surface morphology was examined by SEM. The efficacy of the treatments has been evaluated through static contact angle measurements and capillary water absorption. The optical appearance of the coatings was evaluated by colorimetric measurements. Nanoparticles at suitable concentration gave high values for the static contact angle (up to ∼ 150°), for all stone species even for four months exposure to atmospheric conditions. The coatings, in the water capillary absorption tests, however, behave as expected only for granite even if the long-term water direct contact reduces the hydrophobicity. 相似文献
822.
Ben Sidaway Matthew Bouchard Julie Chasse Jonathan Dunn Andrea Govoni Breanne McPherson 《Research quarterly for exercise and sport》2017,88(2):215-222
Purpose: The requirement for postural stability during the performance of motor skills has been clearly demonstrated in infants, but the necessity for such a postural substrate is not well documented in adults. The present study investigated the role of postural stability during a ballistic ball-kicking task in adults by providing varying degrees of external postural support. Method: In the 1st experiment, 30 participants performed 20 maximal-velocity kicks under each of 3 conditions: grasping a rigid stable handle, light fingertip touch, and grasping a suspended elastic tube. A 2nd experiment with 16 participants varied the position of the stable handle to examine if the handle position in Experiment 1 might simply act as a fulcrum to enhance torque generation. Results: In Experiment 1, ball velocity was significantly higher in the stable-grasp condition in both men and women with the men showing greater improvement relative to the other conditions. Experiment 2 showed that the position of the stable handle did not significantly affect kicking velocity, indicating that the handle was not simply acting as a fulcrum during the kick. Conclusion: Together, the findings suggest that postural stability may be a rate limiter in the performance of dynamic motor tasks in adults. 相似文献
823.
824.
Andrea Bonaccorsi 《Minerva》2008,46(3):285-315
The article addresses the issue of dynamics of science, in particular of new sciences born in twentieth century and developed
after the Second World War (information science, materials science, life science). The article develops the notion of search
regime as an abstract characterization of dynamic patterns, based on three dimensions: the rate of growth, the degree of internal
diversity of science and the associated dynamics (convergent vs. proliferating), and the nature of complementarity. The article
offers a conceptual discussion for the argument that new sciences follow a different pattern than established sciences and
presents preliminary evidence drawn from original data in particle physics, computer science and nanoscience.
相似文献
Andrea BonaccorsiEmail: |
825.
Laura Benton Nelly Joye Emma Sumner Andrea Gauthier Seray Ibrahim Asimina Vasalou 《British journal of educational technology : journal of the Council for Educational Technology》2023,54(5):1314-1331
Digital literacy games can be beneficial for children with reading difficulties as a supplement to classroom instruction and an important feature of these games are the instructional supports, such as feedback. To be effective, feedback needs to build on prior instruction and match a learner's level of prior knowledge. However, there is limited research around the relationship between prior knowledge, instruction and feedback in the context of learning games. This paper presents an empirical study exploring the influence of prior knowledge on response to feedback, in two conditions: with or without instruction. Thirty-six primary children (age 8–11) with reading difficulties participated: each child was assessed for their prior knowledge of two suffix types—noun and adjective suffixes. They subsequently received additional instruction for one suffix type and then played two rounds of a literacy game—one round for each suffix type. Our analysis shows that prior knowledge predicted initial success rates and performance after a verbal hint differently, depending on whether instruction was provided. These results are discussed with regards to learning game feedback design and the impact on different types of knowledge involved in gameplay, as well as other game design elements that might support knowledge building during gameplay.
Practitioner notes
What is already known about this topic- Instructional supports, such as elaborative feedback, are a key feature of learning games.
- To be effective, feedback needs to build on prior instruction and match a learner's level of prior knowledge.
- Prior knowledge is an important moderator to consider in the context of elaborative feedback.
- Providing additional instruction (eg, pre-training) may act as a knowledge enhancer building on children's existing disciplinary expertise, whereas the inclusion of elaborative feedback (eg, a hint) could be seen as a knowledge equaliser enabling children regardless of their prior knowledge to use the pre-training within their gameplay.
- Highlights the importance of children's preferred learning strategies within the design of pre-training and feedback to ensure children are able to use the instructional support provided within the game.
- Possible implications for pre-training and feedback design within literacy games, as well as highlighting areas for further research.
- Pre-training for literacy games should highlight key features of the learning content and explicitly make connections with the target learning objective as well as elaborative feedback.
- Pre-training should be combined with different types of in-game feedback for different types of learners (eg, level of prior knowledge) or depending on the type of knowledge that designers want to build (eg, metalinguistic vs. epilinguistic).
- Modality, content and timing of the feedback should be considered carefully to match the specific needs of the intended target audience and the interaction between them given the primary goal of the game.