全文获取类型
收费全文 | 1728篇 |
免费 | 57篇 |
国内免费 | 12篇 |
专业分类
化学 | 1348篇 |
晶体学 | 14篇 |
力学 | 20篇 |
数学 | 109篇 |
物理学 | 306篇 |
出版年
2023年 | 8篇 |
2021年 | 19篇 |
2020年 | 16篇 |
2019年 | 32篇 |
2018年 | 22篇 |
2017年 | 13篇 |
2016年 | 38篇 |
2015年 | 24篇 |
2014年 | 43篇 |
2013年 | 91篇 |
2012年 | 93篇 |
2011年 | 96篇 |
2010年 | 61篇 |
2009年 | 56篇 |
2008年 | 73篇 |
2007年 | 103篇 |
2006年 | 82篇 |
2005年 | 101篇 |
2004年 | 102篇 |
2003年 | 67篇 |
2002年 | 82篇 |
2001年 | 38篇 |
2000年 | 31篇 |
1999年 | 17篇 |
1998年 | 14篇 |
1997年 | 16篇 |
1996年 | 33篇 |
1995年 | 18篇 |
1994年 | 20篇 |
1993年 | 18篇 |
1992年 | 26篇 |
1991年 | 22篇 |
1990年 | 14篇 |
1989年 | 15篇 |
1988年 | 20篇 |
1987年 | 17篇 |
1986年 | 10篇 |
1985年 | 26篇 |
1984年 | 16篇 |
1983年 | 16篇 |
1982年 | 28篇 |
1981年 | 10篇 |
1980年 | 13篇 |
1979年 | 15篇 |
1978年 | 19篇 |
1977年 | 11篇 |
1976年 | 14篇 |
1975年 | 11篇 |
1974年 | 11篇 |
1973年 | 9篇 |
排序方式: 共有1797条查询结果,搜索用时 15 毫秒
1.
Optical Review - The response of light in a nonlinear dispersive medium is governed by the nonlinear Schrödinger equation (NLSE). In general, for higher order group velocity dispersion (GVD)... 相似文献
2.
Archiv der Mathematik - We prove a general stability theorem for p-class groups of number fields along relative cyclic extensions of degree $$p^2$$ , which is a generalization of a finite-extension... 相似文献
3.
4.
This new method overcomes problems of conventional analytical methodologies such as light scattering and sampling reproducibility issues. We used this method for mechanistic studies of catalytic reactions under heterogeneous conditions. Direct-type hydroxymethylation reactions and Mukaiyama-type hydroxymethylation reactions both catalyzed by a scandium–bipyridine ligand complex under micellar conditions were employed as examples of heterogeneous reactions. For direct-type hydroxymethylation reactions, initial reaction rate assays revealed first-order dependency on both substrate and catalyst. On the other hand, Mukaiyama-type hydroxymethylation reactions showed first-order rate dependency on substrate, zero-order on catalyst and saturation kinetics on formaldehyde.A direct and quantitative method for monitoring heterogeneous organic reactions has been developed by using direct analysis in real time mass spectrometry (DART-MS) with an isotope-labeled reaction product as an internal standard. 相似文献
5.
A simple high‐performance liquid chromatography for the determination of linezolid in human plasma and saliva 下载免费PDF全文
Shuuji Hara Masanobu Uchiyama Masami Yoshinari Taichi Matsumoto Shiro Jimi Atsushi Togawa Tohru Takata Yasushi Takamatsu 《Biomedical chromatography : BMC》2015,29(9):1428-1431
Linezolid is an antimicrobial agent for the treatment of multiresistant Gram‐positive infections. A practical high‐performance liquid chromatography method was developed for the determination of linezolid in human plasma and saliva. Linezolid and an internal standard (o‐ethoxybenzamide) were extracted from plasma and saliva with ethyl acetate and analyzed on a Capcell Pak C18 MG column with UV detection at 254 nm. The calibration curve was linear through the range 0.5–50 µg/mL using a 200 μL sample volume. The intra‐ and interday precisions were all <6.44% for plasma and 5.60% for saliva. The accuracies ranged from 98.8 to 110% for both matrices. The mean recoveries of linezolid were 80.8% for plasma and 79.0% for saliva. This method was used to determine the plasma and saliva concentrations of linezolid in healthy volunteers who were orally administered a 600 mg dose of linezolid. Our liquid–liquid extraction procedure is easy and requires a small volume of plasma or saliva (200 μL). This small volume can be advantageous in clinical pharmacokinetic studies, especially if children participate. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
6.
Fei Ren Takahiko Ueda Yoshikazu Sano Yasushi Takase Toshihiko Umekage 《Journal of Dispersion Science and Technology》2019,40(2):306-317
In recent years, nanobubble technologies have drawn great attention due to their wide applications in many fields of science and technology. From previous studies, a kind of honeycomb structure for high efficiency nanobubble generation has been proposed. In this paper, the numerical simulations of bubbly flow in the honeycomb structure were performed by using a computational fluid dynamics–population balance model (CFD-PBM) coupled model. The numerical model was based on the Eulerian multiphase model and the population balance model (PBM) was used to calculate the bubble size distribution. The bubble size distributions in the honeycomb structure under different work conditions were predicted. Two different drag force models (Schiller-Naumann model and Tomiyama model) and two different aggregation models (Luo model and turbulent aggregation model) were investigated. Both two drag models gave similar prediction of bubble number density distribution at the outlet. The results obtained from Luo model had better reflection of the trend of number density distribution. The turbulence dissipation rate ε can be used to evaluate the nanobubble generating ability. The water tank was not included in the CFD model in this work. The bubbles in the water tank should be studied in the future. 相似文献
7.
8.
9.
Inside Cover: Photoinduced Formation of an Azobenzene‐Based CD‐Active Supramolecular Cyclic Dimer (Chem. Eur. J. 18/2015) 下载免费PDF全文