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991.
The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by using the heterogeneous UV/Fenton process, the CODcr removal rate reached almost 100% for wastewater containing phenol. Compared with the homogeneous process, the developed catalyst could be used at wider pH range in the UV/Fenton process. Comparison of various heterogeneous process showed that heterogeneous UV/Fenton process was best. The heterogeneous UV/Fenton process with Fe-Mn-Cu-Y catalyst is highly efficient in degrading various organic pollutants. 相似文献
992.
The Animation TutorTM is a curriculum project that uses software to supplement instruction in courses such as intermediate algebra. Its purpose is to ground mathematical reasoning in concrete experiences through the use of interactive animation and the virtual manipulation of objects. This article summarizes how the project has progressed from research to practice and back. The first section shows how research helped implement six instructional objectives: emphasize interactivity with reflection, integrate multiple representations, reduce cognitive load, facilitate transfer, replace ineffective static images with animated images, and provide domain-specific knowledge. The last section illustrates the reciprocal nature of research and practice by describing how formative evaluations of the Animation TutorTM program led to laboratory studies aimed at improving instructional materials and student strategies. 相似文献
993.
The Durkheimian concept of the density of social relationships may prove more fruitful than the historical materialist notion
of a social hierarchy for thinking about the social location of epistemic agents in science. To define a scientist’s social
location in terms of the density of her professional relationships with other scientists permits us to give a more precise
characterization of marginalization and thus to formulate more testable hypotheses about marginalized groups in science. The
notion of social density helps to explain not only how some individual scientists are more likely than others to get a hearing
for their ideas, but also how scientific inquiry flourishes more in some societies than in others.
Warren Schmaus is Professor of Philosophy at Illinois Institute of Technology. His research focuses on the history and philosophy of the social sciences, and he is the author of Rethinking Durkheim and His Tradition (Cambridge, 2004) and Durkheim’s Philosophy of Science and the Sociology of Knowledge (Chicago, 1994). He received his Ph.D. in History and Philosophy of Science from the University of Pittsburgh. 相似文献
Warren SchmausEmail: |
Warren Schmaus is Professor of Philosophy at Illinois Institute of Technology. His research focuses on the history and philosophy of the social sciences, and he is the author of Rethinking Durkheim and His Tradition (Cambridge, 2004) and Durkheim’s Philosophy of Science and the Sociology of Knowledge (Chicago, 1994). He received his Ph.D. in History and Philosophy of Science from the University of Pittsburgh. 相似文献
994.
陆江 《浙江大学学报(A卷英文版)》2004,5(3):303-308
Geotechnical research on historical remains can provide new data and distinctive viewpoint for research on soil mechanics. Two Jiangnan Tu-Dun tombs historical remains were investigated by means of in situ and laboratory geotechnical tests. In the present paper the geotechnical properties of these man-made earthworks, especially ageing effect on consolidation and direct shear, and compaction properties of earth fill are discussed. 相似文献
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This study examined how grouping arrangements affect students achievement, social interaction, and motivation. Students of high, average and low ability were randomly assigned to homogeneous or heterogeneous ability groups. All groups attended the same plant biology course. The main results indicate that low-ability students achieve more and are more motivated to learn in heterogeneous groups. Average-ability students perform better in homogeneous groups whereas high-ability students show equally strong learning outcomes in homogeneous and heterogeneous groups. Results on social interaction indicate that heterogeneous groups produce higher proportions of individual elaborations, whereas homogeneous groups use relatively more collaborative elaborations. In the discussion, these differences in social interaction are used to explain the differential effects of grouping arrangements on achievement scores. Practical implications are discussed and topics for further research are advanced. 相似文献
998.
Investigating profiles of lexical quality in preschool and their contribution to first grade reading
Kimberly?A.?Murphy Language Reading Research Consortium Kelly?Farquharson 《Reading and writing》2016,29(9):1745-1770
This longitudinal study investigated profiles of lexical quality domains in preschool children and the extent to which profile membership predicted reading comprehension in first grade. A latent profile analysis was conducted to classify 420 preschool children on lexical quality domains, including orthography, phonology, morphosyntax, and vocabulary. Regression analysis was used to determine whether profile membership was associated with first grade outcomes across reading comprehension and its components (i.e., listening comprehension and word recognition). Results revealed five profiles of lexical quality which were predictive of all three outcomes in first grade. Children in low lexical quality profiles performed more poorly on the outcome measures than children in the higher lexical quality profiles. Additionally, profile membership did differentially predict later reading outcomes. These results suggest that lexical quality profiles are associated with reading and therefore may offer a means of early identification of children who are susceptible to future reading difficulties. 相似文献
999.
Ada?K.?H.?Pak Alice?Cheng-laiEmail author Ivy?F.?Tso Hua?Shu Wenling?Li Richard?C.?Anderson 《Reading and writing》2005,18(5):437-454
This study investigated the development of visual chunking skills in the processing of Chinese characters among Hong Kong
pupils. One-hundred-seventy-nine primary school students from first, second and fourth grades were administered a character
copying task. Children as young as 6 years of age were aware of character units and were able to apply visual chunking strategies
when processing characters. Children in higher grades performed better than those in lower grades on every character type,
and the types of errors they made revealed that their chunking level was higher than that of younger children. Differences
between ability groups emerged in second grade and vanished in fourth grade, suggesting that children with a lower reading
ability are slower to develop advanced chunking skills. 相似文献
1000.