全文获取类型
收费全文 | 10283篇 |
免费 | 98篇 |
国内免费 | 3篇 |
专业分类
教育 | 7070篇 |
科学研究 | 1487篇 |
各国文化 | 70篇 |
体育 | 564篇 |
综合类 | 9篇 |
文化理论 | 113篇 |
信息传播 | 1071篇 |
出版年
2021年 | 84篇 |
2020年 | 85篇 |
2019年 | 147篇 |
2018年 | 247篇 |
2017年 | 259篇 |
2016年 | 323篇 |
2015年 | 213篇 |
2014年 | 188篇 |
2013年 | 1409篇 |
2012年 | 292篇 |
2011年 | 304篇 |
2010年 | 205篇 |
2009年 | 142篇 |
2008年 | 202篇 |
2007年 | 164篇 |
2006年 | 165篇 |
2005年 | 765篇 |
2004年 | 584篇 |
2003年 | 385篇 |
2002年 | 220篇 |
2001年 | 187篇 |
2000年 | 150篇 |
1999年 | 129篇 |
1998年 | 75篇 |
1997年 | 74篇 |
1996年 | 86篇 |
1995年 | 63篇 |
1994年 | 56篇 |
1993年 | 87篇 |
1992年 | 108篇 |
1991年 | 114篇 |
1990年 | 112篇 |
1989年 | 96篇 |
1988年 | 87篇 |
1987年 | 106篇 |
1986年 | 93篇 |
1985年 | 103篇 |
1984年 | 89篇 |
1983年 | 95篇 |
1982年 | 95篇 |
1981年 | 75篇 |
1980年 | 75篇 |
1979年 | 100篇 |
1978年 | 90篇 |
1977年 | 84篇 |
1976年 | 77篇 |
1974年 | 68篇 |
1973年 | 65篇 |
1972年 | 55篇 |
1971年 | 58篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
2.
3.
Theo H?rder 《Informatik - Forschung und Entwicklung》2002,17(3):99-100
Ohne Zusammenfassung 相似文献
4.
Development of maximal oxygen uptake in young elite male cross-country skiers: a longitudinal study.
F Ingjer 《Journal of sports sciences》1992,10(1):49-63
The aim of this study was to investigate the effects of extensive endurance training (15-25 h per week) on the development of maximal oxygen uptake (VO2 max) in boys from puberty. Maximal oxygen uptake was measured a number of times each year from the age of puberty and for the next 6-9 years in seven young male elite cross-country skiers. Mean VO2 max was measured as 76.3 and 80.1 ml kg-1 min-1 at the ages of 14 and 15 years respectively. Despite the fast rate of growth during puberty, maximal aerobic power showed seasonal variations from the age of 14, reaching a plateau at the age of 15, whereas VO2 max (ml kg-2/3 min-1) increased continuously. It is concluded that, during puberty, boys probably attain significant increases in VO2 max when appropriate amounts of endurance training are undertaken. 相似文献
5.
Wolfgang Wahlster J?rg Baus Christian Kray und Antonio Krüger 《Informatik - Forschung und Entwicklung》2001,16(4):233-241
Zusammenfassung. Die intelligente Ressourcenadaption ist eine der gro?en Herausforderungen für die n?chste Generation mobiler Navigationssysteme.
Da man typischerweise mehrere Fortbewegungsarten oder Verkehrsmittel kombinieren muss, um an einen Zielort zu gelangen, muss
sichergestellt werden, dass mobile, allgegenw?rtige Navigationshilfen dies über eine jeweils situationsangepasste Benutzerschnittstelle
unterstützen. Der notwendige Wechsel zwischen verschiedenen Positionierungstechnologien soll für den Endbenutzer m?glichst
unbemerkt bleiben. Im folgenden wird ein hybrides Personennavigationssystem vorgestellt, das die in bestimmten Fortbewegungssituationen
verfügbaren Positionierungstechnologien und deren Genauigkeit optimal nutzt, um die Pr?sentation der Wegbeschreibung auf verschiedene
Endger?te und Ausgabemodalit?ten sowie die kognitive Ressourcenlage des Benutzers zu adaptieren.
Eingegangen am 28. Februar 2001 / Angenommen am 8. August 2001 相似文献
6.
7.
Donald D. Deshler Jean B. Schumaker B. Keith Lenz Janis A. Bulgren Michael F. Hock Jim Knight Barbara J. Ehren 《Learning disabilities research & practice》2001,16(2):96-108
Three factors tied with secondary student success in content‐area reading are demonstrated: (a) validated teacher‐focused and student‐focused interventions, (b) integrated and comprehensive service delivery systems, and (c) well‐designed, data‐based professional developmental programs. Difficult challenges face secondary students with LD and their teachers with regard to these students’ participation and success in required general education classes. Recently, instructional methods and materials have been developed and validated for promoting these students’ success. Some of them focus on how general education teachers plan and teach their content‐area courses; others focus on giving students the strategies they need to respond independently to the demands of their courses. This article describes these instructional methods, a service‐delivery model for implementing these interventions in secondary schools, and professional‐development mechanisms and administrative support that must be in place for the model to be maintained effectively. 相似文献
8.
9.
There is an increasing interest in linking character education programs with social and academic outcomes. The Child Development
Project (CDP) is a character education program that promotes academic and social growth in teachers and students. This theory-driven
evaluation employed a quasi-experimental design with matched control schools. School personnel participated in an intensive
professional development process to learn the CDP model. Performance measures included state-mandated achievement measures,
teacher self-assessment reports, and student attitudes and outcomes. Results yielded support for the CDP model as a strategy
to improve social and, if properly implemented, cognitive outcomes in students; the model also improved teacher self-assessment
and provided information that may facilitate professional growth about school collegiality. Implications for policy and practice
will be discussed. 相似文献
10.