全文获取类型
收费全文 | 11792篇 |
免费 | 10篇 |
国内免费 | 1篇 |
专业分类
教育 | 9137篇 |
科学研究 | 1217篇 |
各国文化 | 3篇 |
体育 | 340篇 |
文化理论 | 384篇 |
信息传播 | 722篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 13篇 |
2020年 | 12篇 |
2019年 | 19篇 |
2018年 | 2187篇 |
2017年 | 2094篇 |
2016年 | 1585篇 |
2015年 | 117篇 |
2014年 | 123篇 |
2013年 | 159篇 |
2012年 | 224篇 |
2011年 | 697篇 |
2010年 | 836篇 |
2009年 | 432篇 |
2008年 | 644篇 |
2007年 | 1152篇 |
2006年 | 74篇 |
2005年 | 397篇 |
2004年 | 446篇 |
2003年 | 361篇 |
2002年 | 131篇 |
2001年 | 9篇 |
2000年 | 19篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 16篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1992年 | 2篇 |
1991年 | 9篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1966年 | 1篇 |
1924年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 250 毫秒
261.
Brigitte Kofler 《Zeitschrift für Hochschulrecht, Hochschulmanagement und Hochschulpolitik: zfhr》2008,7(3):81-90
In der Entscheidung Morgan und Bucher hat der Europäische Gerichtshof zwei Regelungen des deutschen Bundesausbildungsförderungsgesetzes zur Ausbildungsförderung für Auslandsstudien als gegen die Freizügigkeit der Unionsbürger nach Art 18 EGV verstoßend und somit gemeinschaftsrechtswidrig angesehen. Das Urteil unterstreicht die Bedeutung, die der Gerichtshof der Freizügigkeit und der Gleichbehandlung von Unionsbürgern im Bildungsbereich zuerkennt. Dies wird von Österreich auch bei Klärung der Hochschulzugangsproblematik zu berücksichtigen sein. Das durch eine Novelle zum österreichischen Studienförderungsgesetz eingeführte Mobilitätsstipendium ist entsprechend den vom Europäischen Gerichtshof in Morgan und Bucher entwickelten Grundsätzen am Gemeinschaftsrecht zu messen. 相似文献
262.
Exploring the Effects of Financial Aid on the Gap in Student Dropout Risks by Income Level 总被引:1,自引:0,他引:1
Using national survey data and discrete-time logit modeling, this research seeks to understand whether student aid mediates
the relationship between parental income and student dropout behavior. Our analysis confirms that there is a gap in dropout
rates for low-income students compared with their upper income peers, and suggests that some types of aid are associated with
lower risks of dropout. Thus, we examine the interaction between financial aid type and parental income to explore whether,
and if so how, different types of aid may reduce the dropout gap by income level group. We find that the receipt of a Pell
grant is related to narrowing the dropout gap between students from low- and middle-income groups, although overall the interaction
between Pell grant and income is not significant. Loans and work-study aid both have similar effects on student dropout across
all income groups. Methodologically, our results demonstrate the need to model dropout behavior temporally and to avoid main-effect
bias by incorporating interaction effects.
相似文献
Stephen L. DesJardinsEmail: |
263.
Corina J. Logan Alexis J. Breen Alex H. Taylor Russell D. Gray William J. E. Hoppitt 《Learning & behavior》2016,44(1):18-28
New Caledonian crows make and use tools, and tool types vary over geographic landscapes. Social learning may explain the variation in tool design, but it is unknown to what degree social learning accounts for the maintenance of these designs. Indeed, little is known about the mechanisms these crows use to obtain information from others, despite the question’s importance in understanding whether tool behavior is transmitted via social, genetic, or environmental means. For social transmission to account for tool-type variation, copying must utilize a mechanism that is action specific (e.g., pushing left vs. right) as well as context specific (e.g., pushing a particular object vs. any object). To determine whether crows can copy a demonstrator’s actions as well as the contexts in which they occur, we conducted a diffusion experiment using a novel foraging task. We used a nontool task to eliminate any confounds introduced by individual differences in their prior tool experience. Two groups had demonstrators (trained in isolation on different options of a four-option task, including a two-action option) and one group did not. We found that crows socially learn about context: After observers see a demonstrator interact with the task, they are more likely to interact with the same parts of the task. In contrast, observers did not copy the demonstrator’s specific actions. Our results suggest it is unlikely that observing tool-making behavior transmits tool types. We suggest it is possible that tool types are transmitted when crows copy the physical form of the tools they encounter. 相似文献
264.
There is, broadly speaking, an agreement within the international science education community that comprehension of the nature of science (NOS) should be a key element in the scientific literacy of citizens. During the last few decades, several didactic approaches have emerged concerning what and how to teach NOS. Also, one of the basic objectives of science education is for students to become familiar with the skills typical of scientific practice; however, there is little reference to their need to also acquire meta-knowledge about scientific practice (i.e., an understanding of the nature of scientific practice). Among other reasons, this may be due to NOS being essentially identified in most of the predominant proposals with the nature of scientific knowledge. But why not plan the teaching of science to be in tune with real scientific practice for students to learn about the nature of scientific practice at the same time as they are learning science? The answer to this question has given rise to a proposal grounded in ten essential pedagogical principles for the teaching and learning of science in secondary school. These are the principle of formulating questions, the principle of creativity and imagination, the principle of experimentation, the principle of procedural diversity, the principle of errors as opportunity, the principle of modeling, the principle of cooperation and teamwork, the principle of argumentation and discussion, the principle of communication, and the principle of evaluation. The purpose of this article is to present the justification and fundaments of these principles. 相似文献
265.
266.
The pressure to reduce solar energy costs encourages efforts to reduce the thickness of silicon wafers. Thus, the cell bowing problem associated with the use of thin wafers has become increasingly important, as it can lead to the cracking of cells and thus to high yield losses. In this paper, a systematic approach for simulating the cell bowing induced by the firing process is presented. This approach consists of three processes: (1) the material properties are determined using a nanoidentation test; (2) the thicknesses of aluminum (Al) paste and silver (Ag) busbars and fingers are measured using scanning electron microscopy; (3) non-linear finite element analysis (FEA) is used for simulating the cell bowing induced by the firing process. As a result, the bowing obtained using FEA simulation agrees better with the experimental data than that using the bowing calculations suggested in literature. In addition, the total in-plane residual stress state in the wafer/cell due to the firing process can be determined using the FEA simulation. A detailed analysis of the firing-induced stress state in single crystalline silicon (sc-Si), cast, and edge-defined film-fed growth (EFG) multi-crystalline silicon wafers of different thicknesses is presented. Based on this analysis, a simple residual stress calculation is developed to estimate the maximum in-plane principal stress in the wafers. It is also proposed that the metallization pattern, Ag busbars and fingers screen printed on the front of a solar cell, can be designed using this approach. A practical case of a 3-busbar Si solar cell is presented. 相似文献
267.
268.
Maria Gouveia-Pereira Jorge Vala Augusto Palmonari Monica Rubini 《European Journal of Psychology of Education - EJPE》2003,18(3):309-325
This study analysis the relationship between perceptions of the justice of teacher’ behaviour and (a) the legitimation of school authority and (b) the legitimation of institutional authorities outside school. 448 adolescent students participated in the study. In questionnaire participants were asked about (a) perceptions of the justice of teachers’ behaviour; (b) evaluation of the school experience; and (c) evaluation of institutional authorities. Results show that the evaluation of the justice of teacher behaviour, in particular relational and procedural justice, have an impact on the legitimation of the authority of teachers and on the evaluation of institutional authorities outside school. Results also show that the legitimacy granted to teachers is a mediator variable between perceptions of justice in school and evaluation of authorities outside school. These results are discussed in the context of the studies on the relationship between school experience and adolescents attitudes towards authorities, and in the framework of the “Relational Model of Authority” and of the “Group Value Model”. 相似文献
269.
Ng Pak Tee 《Educational Research for Policy and Practice》2004,3(3):183-198
Schools in Singapore are now tasked to develop the spirit of innovation and enterprise in their students. This is in line with the national vision of ‘Thinking Schools, Learning Nation’. This policy initiative, which began in 2004, is set to change the fundamental nature of education in Singapore. This article discusses the innovation and enterprise (I&E) initiative, its major implications for schools in Singapore and the areas still to be addressed in the implementation of the policy. In particular, the article discusses the issues of teachers and school leaders as role models of I&E, I&E as an organic part of school business, the influence of the wider societal culture and values system, and the measurement of success of I&E. The challenge for schools is to go beyond the form of the initiative to bring real substantial and sustainable change through this movement. 相似文献
270.
Eun-hye Park Won-young Bae Jae-yeon Kim Kee-tae Kim Hyun-dong Paik 《Journal of Zhejiang University. Science. B》2017,18(9):816-824
The inhibitory effects of Lactobacillus plantarum-fermented and non-fermented Inula britannica extracts on the tyrosinase activity were comparatively investigated to examine whether and how they improve the whitening activity, and the contents of total flavonoids and polyphenolics as bioactive compounds were determined. The skin whitening activity using in vitro or ex vivo tyrosinase and L-3,4-dihydroxyphenylalanine (L-DOPA) staining was examined. The total flavonoid content (TFC) was increased by 13.4% after 72 h-fermentation. The viabilities of the B16F10 cells treated with the fermented and non-fermented control extracts were 100.26% and 92.15% at 500 μg/ml, respectively. In addition, the inhibition of tyrosinase activity was increased by the fermented samples from 29.33% to 41.74% following fermentation for up to 72 h. The tyrosinase activity of the untreated control group was increased to 145.69% in B16F10 cells. The results showed that I. britannica fermented by L. plantarum dose-dependently inhibited tyrosinase activity, which was stimulated by α-melanocyte stimulating hormone. These results suggest that lactic fermented I. britannica extracts can be used as effective skin-whitening materials. 相似文献