全文获取类型
收费全文 | 487335篇 |
免费 | 4437篇 |
国内免费 | 1292篇 |
专业分类
化学 | 243980篇 |
晶体学 | 6452篇 |
力学 | 24458篇 |
综合类 | 16篇 |
数学 | 67467篇 |
物理学 | 150691篇 |
出版年
2020年 | 3004篇 |
2019年 | 3291篇 |
2018年 | 11696篇 |
2017年 | 12461篇 |
2016年 | 9932篇 |
2015年 | 5017篇 |
2014年 | 6462篇 |
2013年 | 17270篇 |
2012年 | 16922篇 |
2011年 | 26849篇 |
2010年 | 17300篇 |
2009年 | 17201篇 |
2008年 | 24082篇 |
2007年 | 27237篇 |
2006年 | 14731篇 |
2005年 | 19014篇 |
2004年 | 15071篇 |
2003年 | 13789篇 |
2002年 | 11911篇 |
2001年 | 12196篇 |
2000年 | 9601篇 |
1999年 | 7165篇 |
1998年 | 5995篇 |
1997年 | 5938篇 |
1996年 | 5816篇 |
1995年 | 5263篇 |
1994年 | 5319篇 |
1993年 | 4893篇 |
1992年 | 5592篇 |
1991年 | 5606篇 |
1990年 | 5289篇 |
1989年 | 5168篇 |
1988年 | 5121篇 |
1987年 | 5014篇 |
1986年 | 4706篇 |
1985年 | 6550篇 |
1984年 | 6835篇 |
1983年 | 5636篇 |
1982年 | 5882篇 |
1981年 | 5728篇 |
1980年 | 5644篇 |
1979年 | 5646篇 |
1978年 | 6007篇 |
1977年 | 5875篇 |
1976年 | 5922篇 |
1975年 | 5566篇 |
1974年 | 5515篇 |
1973年 | 5763篇 |
1972年 | 3863篇 |
1971年 | 3036篇 |
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
101.
Robert G. W. Anderson 《Ambix》2015,62(4):333-344
Following colonisation of South America by the Spanish, many new naturally occurring substances were sent to Europe. One of these was the silvery, unreactive metal, platinum, discovered in New Grenada in the mid-eighteenth century. It was often found in granular form, associated with gold, and the challenge to chemists was to refine it, produce it as wire or sheet, and determine its chemical properties. This interested the professor of chemistry at the University of Edinburgh, Joseph Black, who was able to obtain samples from London-based Spanish contacts, particularly Ignacio Luzuriaga. This paper examines how Black transmitted his knowledge of the metal to large numbers of students attending his annual course. 相似文献
102.
103.
104.
105.
106.
Thalia Tsiaka Panagiotis Zoumpoulakis Vassilia J. Sinanoglou Constantinos Makris Georgios A. Heropoulos Antony C. Calokerinos 《Analytica chimica acta》2015
High-energy assisted extraction techniques, like ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE), are widely applied over the last years for the recovery of bioactive compounds such as carotenoids, antioxidants and phenols from foods, animals and herbal natural sources. Especially for the case of xanthophylls, the main carotenoid group of crustaceans, they can be extracted in a rapid and quantitative way with the use of UAE and MAE. 相似文献
107.
108.
109.
I. F. Golovnev E. I. Golovneva L. A. Merzhievsky V. M. Fomin V. E. Panin 《Physical Mesomechanics》2015,18(3):179-186
Molecular dynamics simulation was performed to study the formation of cluster structure, interfaces, and surfaces with different curvature radii in a perfect nanocrystal passed through by a nonlinear wave. It is shown that this process is a type of nanostructure self-organization in response to an external energy flux with subsequent development of a strong rotational field. 相似文献
110.
Echabaane M. Hfaiedh S. Smiri B. Saidi F. Dridi C. 《Journal of Solid State Electrochemistry》2021,25(6):1797-1806
Journal of Solid State Electrochemistry - The fast and sensitive detection of copper ions would be essential for water monitoring. Herein, we report a novel development of an impedimetric sensor... 相似文献