全文获取类型
收费全文 | 427159篇 |
免费 | 7893篇 |
国内免费 | 5235篇 |
专业分类
化学 | 212566篇 |
晶体学 | 6337篇 |
力学 | 23115篇 |
综合类 | 331篇 |
数学 | 61989篇 |
物理学 | 135949篇 |
出版年
2021年 | 3447篇 |
2020年 | 4082篇 |
2019年 | 4424篇 |
2018年 | 12651篇 |
2017年 | 13114篇 |
2016年 | 10752篇 |
2015年 | 5410篇 |
2014年 | 7354篇 |
2013年 | 15062篇 |
2012年 | 16083篇 |
2011年 | 24735篇 |
2010年 | 16582篇 |
2009年 | 16446篇 |
2008年 | 21819篇 |
2007年 | 24606篇 |
2006年 | 12215篇 |
2005年 | 15940篇 |
2004年 | 12471篇 |
2003年 | 11777篇 |
2002年 | 10205篇 |
2001年 | 9512篇 |
2000年 | 7605篇 |
1999年 | 5759篇 |
1998年 | 5191篇 |
1997年 | 4960篇 |
1996年 | 4863篇 |
1995年 | 4354篇 |
1994年 | 4539篇 |
1993年 | 4180篇 |
1992年 | 4583篇 |
1991年 | 4631篇 |
1990年 | 4568篇 |
1989年 | 4340篇 |
1988年 | 4366篇 |
1987年 | 4217篇 |
1986年 | 4039篇 |
1985年 | 5146篇 |
1984年 | 5409篇 |
1983年 | 4558篇 |
1982年 | 4676篇 |
1981年 | 4550篇 |
1980年 | 4453篇 |
1979年 | 4564篇 |
1978年 | 4884篇 |
1977年 | 4741篇 |
1976年 | 4888篇 |
1975年 | 4478篇 |
1974年 | 4562篇 |
1973年 | 4749篇 |
1972年 | 3454篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Journal of Fluorescence - This report describes a combined immunofluorescence and fluorescence viability stain applied as one staining solution for rapid detection of live Legionella... 相似文献
2.
Kinetics and Catalysis - The catalytic properties of a nickel phosphide catalyst supported on silica gel in the reductive amination of carbonyl compounds were studied in a flow reactor using... 相似文献
3.
Chuprin A. S. Belova S. A. Bugaenko M. G. Vologzhanina A. V. Loktev A. S. Voloshin Ya. Z. Buznik V. M. Dedov A. G. 《Kinetics and Catalysis》2022,63(1):108-116
Kinetics and Catalysis - A new ruthenium(II) cage complex with polar terminal groups in the apical substituents has been synthesized; the molecular design of the complex contributes to the... 相似文献
4.
Automotive proton exchange membrane fuel cell stacks need to meet manufacturer specified rated beginning-of-life (BOL) performance before being assembled into vehicles and shipped off to customers. The process of “breaking-in” of a freshly assembled stack is often referred to as “conditioning.” It has become an intensely researched area especially in automotive companies, where imminent commercialization of fuel cell electric vehicles (FCEVs) demands a short, energy- and cost-efficient, and practical conditioning protocol. Significant advances in reducing the conditioning time from 1 to 2 days to as low as 4h or less, in some cases without the use of additional inert gases such as nitrogen, and with minimal use of hydrogen, and specialized test stations will be discussed. 相似文献
5.
Nonlinear Dynamics - The perovskite solar cell (PSC) is one of the most promising photovoltaic candidates along with the highly increasing demand for green electricity. One of the main concerns... 相似文献
6.
Lin Yu Wu Yeyu Tan Xuecai Wu Jiawen Huang Kejing Mi Yan Ou Panpan Wei Fucun 《Journal of Solid State Electrochemistry》2022,26(4):959-971
Journal of Solid State Electrochemistry - An ultrasensitive “signal-off–on” electrochemiluminescence (ECL) biosensor is constructed based on f1-TiO2/g-C3N4/PDA for thrombin... 相似文献
7.
Gaineev A. M. Galkina I. V. Davletshin R. R. Davletshina N. V. Kuznetsov N. O. Grishaev D. Yu. Shulayeva M. P. Pozdeev O. K. 《Russian Journal of General Chemistry》2022,92(7):1208-1213
Russian Journal of General Chemistry - Aminophosphabetaines, i.e., isobutyl {[alkyl(dimethyl)ammonio]methyl}phosphonates with higher alkyl substituents at the nitrogen atom, were obtained by a... 相似文献
8.
Sakhautdinova G. F. Sakhautdinov I. M. Mustafin A. G. Yunusov M. S. 《Chemistry of Natural Compounds》2022,58(1):185-186
Chemistry of Natural Compounds - 相似文献
9.
Chemistry of Natural Compounds - O- and N-propylamino-derivatives of betulin and betulonic acid oxime and methyl ester were synthesized. Their antitumor activity against a panel of 60 human cancer... 相似文献
10.
Dan Chen Kaixin Du Xiaochen Niu Hongwei Zhang Xue Zhang Yu Tang Jianchun Zhao 《Biomedical chromatography : BMC》2022,36(3):e5288
Amlexanox, an anti-inflammatory and anti-allergic agent, has been widely used clinically for the treatment of canker sores, asthma, and allergic rhinitis. Recently, amlexanox has received considerable attention in curing nonalcoholic fatty liver diseases and hepatitis virus infection. Herein, we first established a sensitive high-performance liquid chromatography-tandem mass spectrum (LC–MS/MS) method for the determination of amlexanox in rat plasma. Propranolol was used as the internal standard (IS). Using a simple protein precipitation method, the amlexanox and IS were separated with Capcell Pak C18 column (2.0 × 50 mm, 5 μm) and eluted with water and acetonitrile each containing 0.1% formic acid using gradient elution condition at a flow rate of 0.4 mL·min−1. Amlexanox and IS were detected by a triple quadrupole mass in multiple reactive monitoring (MRM) under the transitions of m/z 299.2 → 281.2 and m/z 259.9 → 116.1 with positive electrospray ionization, respectively. The calibration curves of amlexanox were established with the range of 50 to 2000 ng·mL−1 (r2 > 0.99). The validation method consisted of selectivity, accuracy, precision, carryover effect, matrix effect, recovery, dilution effect, and stability. The fully validated method was successfully applied to the pharmacokinetic study of amlexanox in Wistar rats. 相似文献