全文获取类型
收费全文 | 1446篇 |
免费 | 34篇 |
国内免费 | 3篇 |
专业分类
化学 | 870篇 |
晶体学 | 9篇 |
力学 | 36篇 |
数学 | 163篇 |
物理学 | 405篇 |
出版年
2024年 | 1篇 |
2023年 | 12篇 |
2022年 | 25篇 |
2021年 | 58篇 |
2020年 | 39篇 |
2019年 | 39篇 |
2018年 | 41篇 |
2017年 | 33篇 |
2016年 | 57篇 |
2015年 | 51篇 |
2014年 | 66篇 |
2013年 | 102篇 |
2012年 | 108篇 |
2011年 | 120篇 |
2010年 | 82篇 |
2009年 | 75篇 |
2008年 | 103篇 |
2007年 | 84篇 |
2006年 | 79篇 |
2005年 | 64篇 |
2004年 | 43篇 |
2003年 | 17篇 |
2002年 | 31篇 |
2001年 | 22篇 |
2000年 | 19篇 |
1999年 | 13篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 18篇 |
1995年 | 13篇 |
1994年 | 11篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 10篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1972年 | 1篇 |
1937年 | 1篇 |
排序方式: 共有1483条查询结果,搜索用时 15 毫秒
51.
do Nascimento Marreiro Teixeira Ana Siqueira Siqueira Teixeira Paulo Ronaldo Sousa de Oliveira Farias Emanuel Airton Ferraz e Sousa Brandon Moura Sérvulo Kátia Bonfim de Leite da Silva Durcilene Alves Eiras Carla 《Journal of Solid State Electrochemistry》2020,24(5):1143-1155
Journal of Solid State Electrochemistry - The present work proposes a new electrochemical sulfite biosensor based on babassu mesocarp nanoparticles (BMNPs) immobilized on the surface of a pyrolytic... 相似文献
52.
53.
54.
55.
Simple HPLC‐UV for the quantification of a new leishmanicidal candidate (E)‐1‐4(trifluoromethyl) benzylidene)‐5‐(2‐4‐dichlorozoyl) carbonylhydrazine (LASSBio‐1736) in rat plasma for pharmacokinetics assessment
下载免费PDF全文
![点击此处可从《Biomedical chromatography : BMC》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Barbra Katyuschya Sanches Moraes Lisiane Bajerski Alcides Parisotto Carlos Eduardo da Rosa Silva Marina Amaral Alves Eliezer de Jesus Barreiro Rodrigo José Freddo Teresa Dalla Costa Lídia Moreira Lima Sandra Elisa Haas 《Biomedical chromatography : BMC》2016,30(7):1029-1035
In this study, a sensitive HPLC‐UV assay was developed and validated for the determination of LASSBio‐1736 in rat plasma with sodium diclofenac as internal standard (IS). Liquid–liquid extraction using acetonitrile was employed to extract LASSBio‐1736 and IS from 100 μL of plasma previously basified with NaOH 0.1 M. Chromatographic separation was carried on Waters Spherisorb®S5 ODS2 C18 column (150 × 4.6 mm, 5 μm) using an isocratic mobile phase composed by water with triethylamine 0.3% (pH 4), methanol and acetonitrile grade (45:15:40, v/v/v) at a flow rate of 1 mL/min. Both LASSBio‐1736 and IS were eluted at 4.2 and 5 min, respectively, with a total run time of 8 min only. The lower limit of quantification was 0.2 μg/mL and linearity between 0.2 and 4 μg/mL was obtained, with an R2 > 0.99. The accuracy of the method was >90.5%. The relative standard deviations intra and interday were <6.19 and <7.83%, respectively. The method showed the sensitivity, linearity, precision, accuracy and selectivity required to quantify LASSBio‐1736 in preclinical pharmacokinetic studies according to the criteria established by the US Food and Drug Administration and European Medicines Agency. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
56.
Claudianor O. Alves Daniel C. de Morais Filho Giovany M. Figueiredo 《Mathematical Methods in the Applied Sciences》2019,42(14):4862-4875
In this work, we prove the existence of positive solution for the following class of problems where λ>0 and is a potential satisfying some conditions. Using the variational method developed by Szulkin for functionals, which are the sum of a C1 functional with a convex lower semicontinuous functional, we prove that for each large enough λ>0, there exists a positive solution for the problem, and that, as λ→+∞, such solutions converge to a positive solution of the limit problem defined on the domain Ω=int(V?1({0})). 相似文献
57.
Numerical Algorithms - In this paper, we propose and study the iteration complexity of an inexact Douglas-Rachford splitting (DRS) method and a Douglas-Rachford-Tseng’s forward-backward (F-B)... 相似文献
58.
A. P. M. Alves A. S. Araujo F. A. Bezerra K. S. Sousa S. J. G. Lima M. G. Fonseca 《Journal of Thermal Analysis and Calorimetry》2014,117(1):19-26
Acid leaching of aluminosilicates is an interesting procedure for preparing high surface porous silica. Thermal behavior of vermiculite leached with a nitric acid solution at various concentrations was studied by thermogravimetry and differential scanning calorimetry. Activation energies of the dehydration process in selected temperature zones were determined by two different methods: Ozawa–Flynn–Wall and Friedman. The material obtained was characterized through Fourier transform infrared spectroscopy, X-ray diffraction, and nitrogen adsorption at 77 K to relate them to the estimated activation energies. 相似文献
59.
60.
François Clautiaux Cláudio Alves José Valério de Carvalho 《Annals of Operations Research》2010,179(1):317-342
Dual-feasible functions are valuable tools that can be used to compute both lower bounds for different combinatorial problems
and valid inequalities for integer programs. Several families of functions have been used in the literature. Some of them
were defined explicitly, and others not. One of the main objectives of this paper is to survey these functions, and to state
results concerning their quality. We clearly identify dominant subsets of functions, i.e. those which may lead to better bounds or stronger cuts. We also describe different frameworks that can be used to create
dual-feasible functions. With these frameworks, one can get a dominant function based on other ones. Two new families of dual-feasible
functions obtained by applying these methods are proposed in this paper. 相似文献