全文获取类型
收费全文 | 934篇 |
免费 | 64篇 |
国内免费 | 4篇 |
专业分类
化学 | 770篇 |
晶体学 | 3篇 |
力学 | 38篇 |
数学 | 26篇 |
物理学 | 165篇 |
出版年
2023年 | 8篇 |
2022年 | 18篇 |
2021年 | 14篇 |
2020年 | 11篇 |
2019年 | 20篇 |
2018年 | 11篇 |
2017年 | 13篇 |
2016年 | 44篇 |
2015年 | 40篇 |
2014年 | 45篇 |
2013年 | 57篇 |
2012年 | 72篇 |
2011年 | 90篇 |
2010年 | 54篇 |
2009年 | 45篇 |
2008年 | 64篇 |
2007年 | 60篇 |
2006年 | 48篇 |
2005年 | 44篇 |
2004年 | 58篇 |
2003年 | 38篇 |
2002年 | 67篇 |
2001年 | 21篇 |
2000年 | 20篇 |
1999年 | 9篇 |
1998年 | 2篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1983年 | 3篇 |
1979年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1002条查询结果,搜索用时 31 毫秒
51.
52.
53.
Chul‐Soon Lee Zhengfei Dai Seong‐Yong Jeong Chang‐Hoon Kwak Bo‐Young Kim Do Hong Kim Prof. Ho Won Jang Joon‐Shik Park Prof. Jong‐Heun Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7102-7107
Monolayers of periodic porous Co3O4 inverse opal (IO) thin films for gas‐sensor applications were prepared by transferring cobalt‐solution‐dipped polystyrene (PS) monolayers onto sensor substrates and subsequent removal of the PS template by heat treatment. Monolayer Co3O4 IO thin films having periodic pores (d≈500 nm) showed a high response of 112.9 to 5 ppm C2H5OH at 200 °C with low cross‐responses to other interfering gases. Moreover, the selective detection of xylene and methyl benzenes (xylene+toluene) could be achieved simply by tuning the sensor temperature to 250 and 275 °C, respectively, so that multiple gases can be detected with a single chemiresistor. Unprecedentedly high ethanol response and temperature‐modulated control of selectivity with respect to ethanol, xylene, and methyl benzenes were attributed to the highly chemiresistive IO nanoarchitecture and to the tuned catalytic promotion of different gas‐sensing reactions, respectively. These well‐ordered porous nanostructures could have potential in the field of high‐performance gas sensors based on p‐type oxide semiconductors. 相似文献
54.
A lamellar-structured crystalline polypyrrole (PPy) supramolecular assembly was prepared by surfactant templating, and the regularly linked amorphous PPy nanoparticles with tunable window sizes could play the role of crystalline lattices in the supramolecular assembly. 相似文献
55.
Krokovny P Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bay A Bedny I Behera PK Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fukunaga C Gabyshev N Garmash A Gershon T Golob B Gordon A Guo R Haba J Hanagaki K Handa F Harada Y Hayashii H Hazumi M Heenan EM Higuchi T Hinz L Hojo T 《Physical review letters》2002,89(23):231804
We report the first observation of a B meson decay that is not accessible by a direct spectator process. The channel B(0)-->D(+)(s)K- is found in a sample of 85 x 10(6) BB; events, collected with the Belle detector at KEKB, with a branching fraction B(B(0)-->D(+)(s)K-)=(4.6(+1.2)(-1.1)+/-1.3) x 10(-5). We also obtain evidence for the B0-->D(+)(s)pi(-) decay with branching fraction B(B0-->D(+)(s)pi(-))=(2.4(+1.0)(-0.8)+/-0.7) x 10(-5). This value may be used to extract a model-dependent value of |V(ub)|. 相似文献
56.
[structure: see text] A yttrium(III) complex derived from proligand 7c has been shown to be a superior catalyst for enantioselective intramolecular alkene hydroaminations that provide cyclic amines with ee's ranging from 69% to 89%. 相似文献
57.
58.
59.
Ion pair amphiphiles (IPA) composed of one proton-deionizable single or double alkyl chain ammonium surfactant and one anionic carboxylate surfactant with polymerizable dithiolane ring are prepared to develop polymerized microcapsules that can recognize pH change and transform itself under basic condition, thus releasing encapsulated materials at the desired point. Combination of pH-sensitivity and polymeric solid structure, if fully developed, endows the IPA vesicle with smart function that is highly valuable in drug delivery application. Reasons for such high pH-sensitive vesicle transformation are sought from combined physical properties such as turbidity, zeta potential, surface tension, and release rate of marker through the vesicle membrane. 相似文献
60.