全文获取类型
收费全文 | 305篇 |
免费 | 10篇 |
专业分类
化学 | 214篇 |
晶体学 | 4篇 |
力学 | 8篇 |
数学 | 29篇 |
物理学 | 60篇 |
出版年
2023年 | 2篇 |
2022年 | 11篇 |
2021年 | 10篇 |
2020年 | 10篇 |
2019年 | 9篇 |
2018年 | 13篇 |
2017年 | 4篇 |
2016年 | 20篇 |
2015年 | 9篇 |
2014年 | 13篇 |
2013年 | 17篇 |
2012年 | 12篇 |
2011年 | 21篇 |
2010年 | 12篇 |
2009年 | 8篇 |
2008年 | 10篇 |
2007年 | 15篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1987年 | 4篇 |
1985年 | 3篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1981年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1970年 | 3篇 |
1969年 | 4篇 |
1968年 | 2篇 |
1967年 | 4篇 |
1966年 | 3篇 |
1965年 | 3篇 |
1964年 | 2篇 |
1958年 | 1篇 |
排序方式: 共有315条查询结果,搜索用时 15 毫秒
21.
22.
Journal of Applied Mechanics and Technical Physics - A partially invariant solution of a three-dimensional problem with a free boundary for the Navier–Stokes equations is studied. The flow... 相似文献
23.
Dagmar Medková Mariya Ptashnyk Werner Varnhorn 《Mathematical Methods in the Applied Sciences》2015,38(17):3968-3979
With methods of potential theory, we develop a representation of a solution of the coupled Stokes–Darcy model in a Lipschitz domain for boundary data in H?1/2. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
24.
25.
Mariya I. Meschaninova Nina S. Entelis Elena L. Chernolovskaya Alya G. Venyaminova 《Molecules (Basel, Switzerland)》2021,26(8)
One of the ways to efficiently deliver various drugs, including therapeutic nucleic acids, into the cells is conjugating them with different transport ligands via labile or stable bonds. A convenient solid-phase approach for the synthesis of 5′-conjugates of oligonucleotides with biodegradable pH-sensitive hydrazone covalent bonds is proposed in this article. The approach relies on introducing a hydrazide of the ligand under aqueous/organic media to a fully protected support-bound oligonucleotide containing aldehyde function at the 5′-end. We demonstrated the proof-of-principle of this approach by synthesizing 5′-lipophilic (e.g., cholesterol and α-tocopherol) conjugates of modified siRNA and non-coding RNAs imported into mitochondria (antireplicative RNAs and guide RNAs for Mito-CRISPR/system). The developed method has the potential to be extended for the synthesis of pH-sensitive conjugates of oligonucleotides of different types (ribo-, deoxyribo-, 2′-O-methylribo-, and others) with ligands of different nature. 相似文献
26.
Nikolai V. Tsvetkov Mariya E. Mikhailova Nina G. Mikusheva Alexey A. Lezov Alexander S. Gubarev Elena V. Lebedeva 《International Journal of Polymer Analysis and Characterization》2017,22(1):27-34
Conformational and dynamo-optical properties of a homologous series of poly(cetyltrimethylammonium 2-acrylamido-2-methylpropane sulfonates) with molecular masses ranging from 80 to 700?kDa were studied in chloroform solutions by viscometry, dynamic light scattering, sedimentation, and flow birefringence. The Mark–Kuhn–Houwink Equations for this polymer in chloroform were obtained; the values of hydrodynamic diameter and the Kuhn segment length as well as the value of intrinsic anisotropy of polarizability of the monomer unit were defined. 相似文献
27.
This paper proposes a new multi-criteria decision analysis (MCDA) model that uses a series of existing intuitive and analytical
methods to systematically capture both objective and subjective beliefs and preferences from a group of decision makers (DMs).
A defuzzification method that combines entropy and the theory of displaced ideal synthesizes crisp values from the DMs’ subjective
judgments. This approach assists the DMs in their selection process by plotting alternatives in a four quadrant graph and
considering their Euclidean distance from the “ideal” choice. A pilot study illustrates the details of the proposed method.
The DMs were a group of graduate students from the University of Paderborn in Germany. The pilot study concerned the addition
of new members into the European Union (EU), a decision that has profound economic and political effects on both the entering
and existing members of the Union. The DMs were required to consider a large number of internal strengths and weaknesses and
external opportunities and threats in assessing the decision to enlarge the EU. Although the pilot study was not performed
by actual DMs from the EU, it was an excellent platform for testing the proposed model. 相似文献
28.
A. I. Fedotova Yu. M. Zhuravleva V. E. Maizlish G. P. Shaposhnikov 《Russian Journal of General Chemistry》2013,83(4):757-761
Demetallation of magnesium tetra-4-morpholinyl(piperidinyl)-5-R-substituted phthalocyanines was performed to obtain the corresponding metal-free phthalocyanines. Their electronic absorption spectra were shown to depend on the nature of the solvent. It was found that both the saturated heterocycle and the oxyaryl substituent have almost no effect on the position of the absorption maximum. 相似文献
29.
Yu. A. Zhuravleva 《Siberian Mathematical Journal》1992,33(3):434-444
Volgograd. Translated from Sibirskii Matematicheskii Zhurnal, Vol. 33, No. 3, pp. 78–90, May–June, 1992. 相似文献
30.