全文获取类型
收费全文 | 7381篇 |
免费 | 335篇 |
国内免费 | 64篇 |
专业分类
化学 | 5215篇 |
晶体学 | 37篇 |
力学 | 193篇 |
数学 | 1253篇 |
物理学 | 1082篇 |
出版年
2023年 | 49篇 |
2022年 | 60篇 |
2021年 | 200篇 |
2020年 | 155篇 |
2019年 | 166篇 |
2018年 | 166篇 |
2017年 | 130篇 |
2016年 | 292篇 |
2015年 | 273篇 |
2014年 | 304篇 |
2013年 | 508篇 |
2012年 | 526篇 |
2011年 | 626篇 |
2010年 | 389篇 |
2009年 | 302篇 |
2008年 | 530篇 |
2007年 | 467篇 |
2006年 | 474篇 |
2005年 | 403篇 |
2004年 | 341篇 |
2003年 | 256篇 |
2002年 | 220篇 |
2001年 | 63篇 |
2000年 | 69篇 |
1999年 | 46篇 |
1998年 | 53篇 |
1997年 | 62篇 |
1996年 | 63篇 |
1995年 | 45篇 |
1994年 | 40篇 |
1993年 | 41篇 |
1992年 | 40篇 |
1991年 | 39篇 |
1990年 | 26篇 |
1989年 | 19篇 |
1988年 | 13篇 |
1987年 | 19篇 |
1986年 | 23篇 |
1985年 | 27篇 |
1984年 | 35篇 |
1983年 | 22篇 |
1982年 | 22篇 |
1981年 | 31篇 |
1980年 | 24篇 |
1979年 | 17篇 |
1978年 | 24篇 |
1977年 | 18篇 |
1976年 | 10篇 |
1974年 | 10篇 |
1973年 | 9篇 |
排序方式: 共有7780条查询结果,搜索用时 125 毫秒
1.
2.
3.
Numerical Algorithms - We develop a formal construction of a pointwise divergence-free basis in the nonconforming virtual element method of arbitrary order for the Stokes problem introduced in Zhao... 相似文献
4.
Humberto Andre Potes-Lesoinne Fernando Ramirez-Alvarez Victor H. Perez-Gonzalez Sergio O. Martinez-Chapa Roberto Carlos Gallo-Villanueva 《Electrophoresis》2022,43(1-2):249-262
The survival of living beings, including humanity, depends on a continuous supply of clean water. However, due to the development of industry, agriculture, and population growth, an increasing number of wastewaters is discarded, and the negative effects of such actions are clear. The first step in solving this situation is the collection and monitoring of pollutants in water bodies to subsequently facilitate their treatment. Nonetheless, traditional sensing techniques are typically laboratory-based, leading to potential diminishment in analysis quality. In this paper, the most recent developments in micro- and nano-electrochemical devices for pollutant detection in wastewater are reviewed. The devices reviewed are based on a variety of electrodes and the sensing of three different categories of pollutants: nutrients and phenolic compounds, heavy metals, and organic matter. From these electrodes, Cu, Co, and Bi showed promise as versatile materials to detect a grand variety of contaminants. Also, the most commonly used material is glassy carbon, present in the detection of all reviewed analytes. 相似文献
5.
Landgrave-Barbosa Fernando Marmolejo-Valencia Andrés F. Baray-Calderón Alejandro Hu Hailin Aguilar-Cordero Julio César Amador-Bedolla Carlos Ugalde-Saldivar Víctor M. 《Journal of Solid State Electrochemistry》2022,26(3):649-661
Journal of Solid State Electrochemistry - A study of poly(3-hexylthiophene) (P3HT) thin films by spin-coating process, deposited on conducting glass substrates of fluorine-doped tin oxide (FTO), is... 相似文献
6.
7.
Nguyen H. N. Vu M. A. Hy D. M. Ta N. A. Do A. T. 《Journal of Applied and Industrial Mathematics》2021,15(2):315-325
Journal of Applied and Industrial Mathematics - In this paper, we introduce a nonlinear Lanchester-type model involving supply units. The model describes a battle where the Blue party consisting of... 相似文献
8.
da Silva Andre Luis Ferreira Salas Ruben Andres Silva Emilio Carlos Nelli 《Meccanica》2021,56(2):417-437
Meccanica - Fiber reinforced materials are used in assorted engineering application and for this reason, new additive manufacturing technologies have been developed for this type of materials. With... 相似文献
9.
Application of TiO2-nanotubes/PbO2 as an anode for the electrochemical elimination of Acid Red 1 dye
Santos José Eudes L. de Moura Dayanne Chianca da Silva Djalma Ribeiro Panizza Marco Martínez-Huitle Carlos A. 《Journal of Solid State Electrochemistry》2019,23(2):351-360
Journal of Solid State Electrochemistry - In this study, galvanostatic electrolysis, through the use of the platinum supported on Ti (Ti/Pt) and Ti/TiO2-nanotubes/PbO2 anodes, was conducted in an... 相似文献
10.
Tomas Do Roman Guran Rea Jarosova Petra Ondrackova Zbysek Sladek Martin Faldyna Vojtech Adam Ondrej Zitka 《Molecules (Basel, Switzerland)》2020,25(23)
Respiratory infections are a real threat for humans, and therefore the pig model is of interest for studies. As one of a case for studies, Actinobacillus pleuropneumoniae (APP) caused infections and still worries many pig breeders around the world. To better understand the influence of pathogenic effect of APP on a respiratory system—lungs and tracheobronchial lymph nodes (TBLN), we aimed to employ matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-TOF MSI). In this study, six pigs were intranasally infected by APP and two were used as non-infected control, and 48 cryosections have been obtained. MALDI-TOF MSI and immunohistochemistry (IHC) were used to study spatial distribution of infectious markers, especially interleukins, in cryosections of porcine tissues of lungs (necrotic area, marginal zone) and tracheobronchial lymph nodes (TBLN) from pigs infected by APP. CD163, interleukin 1β (IL-1β) and a protegrin-4 precursor were successfully detected based on their tryptic fragments. CD163 and IL-1β were confirmed also by IHC. The protegrin-4 precursor was identified by MALDI-TOF/TOF directly on the tissue cryosections. CD163, IL-1β and protegrin-4 precursor were all significantly (p < 0.001) more expressed in necrotic areas of lungs infected by APP than in marginal zone, TBLN and in control lungs. 相似文献