全文获取类型
收费全文 | 1504篇 |
免费 | 48篇 |
国内免费 | 2篇 |
专业分类
化学 | 1137篇 |
晶体学 | 10篇 |
力学 | 14篇 |
数学 | 41篇 |
物理学 | 352篇 |
出版年
2022年 | 10篇 |
2021年 | 9篇 |
2020年 | 10篇 |
2019年 | 22篇 |
2018年 | 12篇 |
2016年 | 23篇 |
2015年 | 20篇 |
2014年 | 34篇 |
2013年 | 68篇 |
2012年 | 68篇 |
2011年 | 95篇 |
2010年 | 39篇 |
2009年 | 34篇 |
2008年 | 90篇 |
2007年 | 102篇 |
2006年 | 99篇 |
2005年 | 112篇 |
2004年 | 92篇 |
2003年 | 68篇 |
2002年 | 51篇 |
2001年 | 23篇 |
2000年 | 12篇 |
1999年 | 20篇 |
1998年 | 19篇 |
1997年 | 19篇 |
1996年 | 12篇 |
1995年 | 14篇 |
1994年 | 15篇 |
1993年 | 13篇 |
1992年 | 19篇 |
1991年 | 20篇 |
1990年 | 9篇 |
1989年 | 10篇 |
1987年 | 9篇 |
1986年 | 11篇 |
1985年 | 15篇 |
1984年 | 23篇 |
1983年 | 14篇 |
1982年 | 18篇 |
1981年 | 10篇 |
1980年 | 14篇 |
1979年 | 15篇 |
1978年 | 19篇 |
1977年 | 19篇 |
1976年 | 18篇 |
1975年 | 14篇 |
1974年 | 12篇 |
1973年 | 9篇 |
1972年 | 9篇 |
1968年 | 8篇 |
排序方式: 共有1554条查询结果,搜索用时 46 毫秒
91.
92.
Miyazaki H. Kato J. Kawai S. Hatayama H. Uchida K. Otsuki M. Tagami J. Yokoo S. 《Laser Physics》2011,21(12):2128-2131
This study evaluated the surgical performance of a 405-nm diode laser in vivo, using living rat liver tissue. Tissue was incised
by irradiation with the laser at low output power ranging from 1 W (722 W/cm2) to 3 W (2165 W/cm2) on a manual control at a rate of 1 mm/s. As a control, incisions using a stainless scalpel were compared. Immediately after
operation, the surface of the incisions was macroscopically observed and histopathologically evaluated by microscopy. Laser-ablated
liver tissue was smooth with observable signs of remnant carbonization and easily acquired hemostasis. The thickness of the
denatured layer increased in proportion to the output power; the coagulation layer did not thicken accordingly. Bleeding could
not be stopped for tissues incised with the stainless scalpel. The 405-nm diode laser thus proved to be effective for ablating
soft tissue with high hemostatic ability at low power. 相似文献
93.
Uchiyama N Matsunaga K Kiuchi F Honda G Tsubouchi A Nakajima-Shimada J Aoki T 《Chemical & pharmaceutical bulletin》2002,50(11):1514-1516
Trypanocidal constituents of dried leaves of Laurus nobilis L. (Lauraceae) were examined. Activity-guided fractionation of the methanol extract resulted in the isolation of two guaianolides, dehydrocostus lactone (1) and zaluzanin D (2), and a new p-menthane hydroperoxide, (1R,4S)-1-hydroperoxy-p-menth-2-en-8-ol acetate (3). The minimum lethal concentrations of these compounds against epimastigotes of Trypanosoma cruzi were 6.3, 2.5, and 1.4 microM, respectively. 相似文献
94.
Controlled chemical reaction of single trans-2-butene molecules on the Pd(110) surface was realized by dosing tunneling electrons from the tip of a scanning tunneling microscope at 4.7 K. The reaction product was identified as a 1,3-butadiene molecule by inelastic electron tunneling spectroscopy. Threshold voltage for the reaction is approximately 365 mV, which coincides with the vibrational excitation of the C-H stretching mode. The reaction was ascertained to be caused by C-H bond dissociation by multiple vibrational excitations of the C-H stretching mode via inelastic electron tunneling process. 相似文献
95.
Charge transport properties of β-LiAl were studied in the composition range of 48.0–50.2 at.% Li. Measurements were made on single crystal samples and down to the liquid He temperature. The resistivity changes linearly with temperature above 125 K, with a thermal coefficient of 72–95nΩ cm K?1. The Matthiessen law was obeyed very well. A component dependent on temperature, which was described by the Grüneisen formula, is insensitive to a change of the chemical composition. On the other hand, the residual resistivity depends largely on the composition and contributes up to 58% of the total resistivity in Li0.498. It is chiefly due to the substituted Li atoms on the Al sublattice. 相似文献
96.
97.
98.
99.
100.