全文获取类型
收费全文 | 2177篇 |
免费 | 173篇 |
国内免费 | 4篇 |
专业分类
化学 | 1596篇 |
晶体学 | 4篇 |
力学 | 79篇 |
数学 | 327篇 |
物理学 | 348篇 |
出版年
2023年 | 36篇 |
2022年 | 26篇 |
2021年 | 53篇 |
2020年 | 116篇 |
2019年 | 85篇 |
2018年 | 49篇 |
2017年 | 43篇 |
2016年 | 126篇 |
2015年 | 102篇 |
2014年 | 94篇 |
2013年 | 104篇 |
2012年 | 145篇 |
2011年 | 158篇 |
2010年 | 94篇 |
2009年 | 67篇 |
2008年 | 102篇 |
2007年 | 86篇 |
2006年 | 71篇 |
2005年 | 66篇 |
2004年 | 44篇 |
2003年 | 48篇 |
2002年 | 60篇 |
2001年 | 22篇 |
2000年 | 26篇 |
1999年 | 23篇 |
1998年 | 31篇 |
1997年 | 15篇 |
1996年 | 19篇 |
1995年 | 28篇 |
1994年 | 26篇 |
1993年 | 22篇 |
1992年 | 14篇 |
1991年 | 13篇 |
1990年 | 10篇 |
1989年 | 11篇 |
1986年 | 19篇 |
1985年 | 15篇 |
1984年 | 16篇 |
1983年 | 16篇 |
1982年 | 14篇 |
1981年 | 12篇 |
1980年 | 7篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1972年 | 7篇 |
1971年 | 7篇 |
1967年 | 8篇 |
排序方式: 共有2354条查询结果,搜索用时 31 毫秒
51.
52.
53.
54.
55.
Lisa Roeder Philipp Bender Andreas Tschöpe Rainer Birringer Annette M. Schmidt 《Journal of polymer science. Part A, Polymer chemistry》2012,50(24):1772-1781
The mechanical characterization of complex soft matter by quasi-static magnetometry using nanoscopic magnetic probes is demonstrated for model hydrogels doped with two types of elongated magnetic nanoparticles. Chemically crosslinked poly(acrylamide) (PAAm) hydrogels serve as the matrix in which nickel nanorods or weakly magnetized hematite (α-Fe2O3) ellipsoids are embedded as local probes. We investigated the swelling behavior of the ferrogels in order to verify that their equilibrium swelling degree in water is not influenced by the probes, shows a good correlation with the Frenkel–Flory–Rehner model. The proposed magnetomechanical method relies on a correlation between the shear modulus of the PAAm hydrogel matrix and the coercive fields of the corresponding isotropic ferrogels. By extending the Stoner–Wohlfarth model for single-domain blocked magnetic particles by a term for particle rotation in an elastic matrix, information on the shear modulus of the matrix can be obtained. Comparison of the results with the expected relation from rubber elasticity theory illustrates both the general potential as well as the limits of the approach. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
56.
Dr. Michael L. Lejkowski Dr. Ronald Lindner Dr. Takeharu Kageyama Dr. Gabriella É. Bódizs Dipl.‐Chem. Philipp N. Plessow Dr. Imke B. Müller Dr. Ansgar Schäfer Dr. Frank Rominger Prof. Dr. Peter Hofmann Dr. Cornelia Futter Dr. Stephan A. Schunk Dr. Michael Limbach 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(44):14017-14025
For more than three decades the catalytic synthesis of acrylates from the cheap and abundantly available C1 building block carbon dioxide and alkenes has been an unsolved problem in catalysis research, both in academia and industry. Herein, we describe a homogeneous catalyst based on nickel that permits the catalytic synthesis of the industrially highly relevant acrylate sodium acrylate from CO2, ethylene, and a base, as demonstrated, at this stage, by a turnover number of greater than 10 with respect to the metal. 相似文献
57.
Bharat Kumar Ruth L. Viboh Margel C. Bonifacio William B. Thompson Jonathan C. Buttrick Babe C. Westlake Min‐Soo Kim Robert W. Zoellner Sergey A. Varganov Philipp Mrschel Jaroslav Teteruk Martin U. Schmidt Benjamin T. King 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(51):13071-13071
58.
59.
The effects of a semi-transparent reacting particle irradiation are analysed using a transient combined heat transfer model. Direct uniform irradiation is found to be favourable for particle heating and decomposition, decreasing the total reaction time by a factor of 3.3 as compared to that for non-uniform irradiation. In both cases heat transfer from the surface to the reaction zone is the process limiting mechanism. 相似文献
60.
G.K. Surya Prakash Laxman Gurung Philipp Christoph SchmidFang Wang Tisa Elizabeth ThomasChiradeep Panja Thomas MathewGeorge A. Olah 《Tetrahedron letters》2014
Nitroso compounds are versatile reagents in synthetic organic chemistry. Herein, we disclose a feasible protocol for the ipso-nitrosation of aryl boronic acids using chlorotrimethylsilane–sodium nitrite unison as nitrosation reagent system. 相似文献