全文获取类型
收费全文 | 339349篇 |
免费 | 4174篇 |
国内免费 | 698篇 |
专业分类
化学 | 166107篇 |
晶体学 | 4376篇 |
力学 | 12586篇 |
综合类 | 10篇 |
数学 | 37470篇 |
物理学 | 91180篇 |
无线电 | 32492篇 |
出版年
2020年 | 2869篇 |
2019年 | 3054篇 |
2018年 | 4272篇 |
2017年 | 4169篇 |
2016年 | 6374篇 |
2015年 | 4076篇 |
2014年 | 5869篇 |
2013年 | 14058篇 |
2012年 | 10987篇 |
2011年 | 12728篇 |
2010年 | 9197篇 |
2009年 | 9122篇 |
2008年 | 12587篇 |
2007年 | 12857篇 |
2006年 | 11861篇 |
2005年 | 11092篇 |
2004年 | 10201篇 |
2003年 | 9123篇 |
2002年 | 8943篇 |
2001年 | 9226篇 |
2000年 | 7646篇 |
1999年 | 5986篇 |
1998年 | 5391篇 |
1997年 | 5267篇 |
1996年 | 5041篇 |
1995年 | 4607篇 |
1994年 | 4784篇 |
1993年 | 4437篇 |
1992年 | 4867篇 |
1991年 | 4868篇 |
1990年 | 4760篇 |
1989年 | 4476篇 |
1988年 | 4505篇 |
1987年 | 4113篇 |
1986年 | 3905篇 |
1985年 | 5074篇 |
1984年 | 5305篇 |
1983年 | 4446篇 |
1982年 | 4546篇 |
1981年 | 4484篇 |
1980年 | 4390篇 |
1979年 | 4320篇 |
1978年 | 4625篇 |
1977年 | 4533篇 |
1976年 | 4606篇 |
1975年 | 4220篇 |
1974年 | 4308篇 |
1973年 | 4475篇 |
1972年 | 3145篇 |
1971年 | 2606篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
Smirnova T. D. Zhelobitskaya E. A. Danilina T. G. 《Journal of Analytical Chemistry》2022,77(8):1000-1004
Journal of Analytical Chemistry - Silver nanoparticles modified with Eu3+ ions increase the intensity of the fluorescence signal by a factor of 125 in an analytical system containing doxycycline as... 相似文献
34.
Daulbaev O. Isaenko L. I. Bogdzel’ A. A. Lobanov S. I. Krinitsyn P. G. Milkov V. M. Belushkin A. V. 《Crystallography Reports》2022,67(3):464-469
Crystallography Reports - Two LiInSe2 single crystals, grown under different conditions, have been studied. Characteristics of these crystals for neutron detection have been compared using... 相似文献
35.
Mohammed Amin Salih Venkatachalam K. Hubálovský S. Trojovský P. Prabu P. 《Mobile Networks and Applications》2022,27(3):1050-1059
Mobile Networks and Applications - 5G/6G communication are first generation high speed wireless communication network which integrates the aerial data, terrestrial data and maritime data via... 相似文献
36.
Young Been Kim Sung Hyeon Jung Dong Su Kim Nishad G. Deshpande Hee Won Suh Hak Hyeon Lee Ji Hoon Choi Ho Seong Lee Hyung Koun Cho 《Advanced functional materials》2021,31(38):2102439
Antimony triselenide (Sb2Se3) nanoflake-based nitrogen dioxide (NO2) sensors exhibit a progressive bifunctional gas-sensing performance, with a rapid alarm for hazardous highly concentrated gases, and an advanced memory-type function for low-concentration (<1 ppm) monitoring repeated under potentially fatal exposure. Rectangular and cuboid shaped Sb2Se3 nanoflakes, comprising van der Waals planes with large surface areas and covalent bond planes with small areas, can rapidly detect a wide range of NO2 gas concentrations from 0.1 to 100 ppm. These Sb2Se3 nanoflakes are found to be suitable for physisorption-based gas sensing owing to their anisotropic quasi-2D crystal structure with extremely enlarged van der Waals planes, where they are humidity-insensitive and consequently exhibit an extremely stable baseline current. The Sb2Se3 nanoflake sensor exhibits a room-temperature/low-voltage operation, which is noticeable owing to its low energy consumption and rapid response even under a NO2 gas flow of only 1 ppm. As a result, the Sb2Se3 nanoflake sensor is suitable for the development of a rapid alarm system. Furthermore, the persistent gas-sensing conductivity of the sensor with a slow decaying current can enable the development of a progressive memory-type sensor that retains the previous signal under irregular gas injection at low concentrations. 相似文献
37.
Chueshova A. G. Pavlova L. A. Peshcherova S. M. Nepomnyashchikh A. I. 《Crystallography Reports》2021,66(7):1206-1215
Crystallography Reports - The orientation of grains and the special boundaries formed by them in multicrystalline silicon has been studied by electron backscattered diffraction. It is found that... 相似文献
38.
Crystallography Reports - The specific features of the formation of crystallites in gallium arsenide crystals grown by the Czochralski method have been investigated. The crystallites are found to... 相似文献
39.
Tomáš Hložek Martin Štícha Miroslava Bursová Ivan Jelínek Petr Tůma Radomír Čabala 《Electrophoresis》2020,41(18-19):1564-1567
Riociguat is novel antihypertensive drug for treatment of pulmonary hypertension. As such, it is still being tested in many clinical and pharmacokinetic trials. Existing methods that determine serum riociguat and desmethylriociguat (DMR) are based solely on liquid chromatography with mass spectrometry. Therefore, we present a novel capillary electrophoresis with mass spectrometry method (CE-MS) for their determination in human serum as alternative method for ongoing trials. Complete resolution of both analytes was achieved by means of pH optimization of ammonium formate background electrolytes that are fully compatible with ESI/MS detection. Simple liquid-liquid extraction was used as sample pretreatment. The calibration dependence of the method was linear (in the range of 10–1000 ng/mL), with adequate accuracy (90.1–114.9%) and precision (13.4%). LOD and LOQ were arbitrarily set at 10 ng/mL for both analytes. Clinical applicability was validated using serum samples from patients treated with riociguat in pharmacokinetic study and the results corresponded with reference HPLC-MS/MS values. Capillary electrophoresis proved to be sensitive and selective tool for the analysis of riociguat and DMR. 相似文献
40.