全文获取类型
收费全文 | 8203篇 |
免费 | 1453篇 |
国内免费 | 887篇 |
专业分类
化学 | 6011篇 |
晶体学 | 66篇 |
力学 | 495篇 |
综合类 | 43篇 |
数学 | 1021篇 |
物理学 | 2907篇 |
出版年
2024年 | 3篇 |
2023年 | 203篇 |
2022年 | 222篇 |
2021年 | 272篇 |
2020年 | 457篇 |
2019年 | 387篇 |
2018年 | 337篇 |
2017年 | 276篇 |
2016年 | 376篇 |
2015年 | 402篇 |
2014年 | 499篇 |
2013年 | 613篇 |
2012年 | 761篇 |
2011年 | 819篇 |
2010年 | 543篇 |
2009年 | 489篇 |
2008年 | 471篇 |
2007年 | 441篇 |
2006年 | 464篇 |
2005年 | 346篇 |
2004年 | 267篇 |
2003年 | 223篇 |
2002年 | 254篇 |
2001年 | 150篇 |
2000年 | 154篇 |
1999年 | 173篇 |
1998年 | 124篇 |
1997年 | 122篇 |
1996年 | 135篇 |
1995年 | 106篇 |
1994年 | 93篇 |
1993年 | 60篇 |
1992年 | 64篇 |
1991年 | 55篇 |
1990年 | 44篇 |
1989年 | 38篇 |
1988年 | 31篇 |
1987年 | 14篇 |
1986年 | 16篇 |
1985年 | 16篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1957年 | 3篇 |
1935年 | 1篇 |
1931年 | 1篇 |
1930年 | 3篇 |
1922年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
1.
Nonlinear Dynamics - In this paper, a (2+1)-dimensional Caudrey–Dodd–Gibbon–Kotera–Sawada system is investigated in fluid mechanics via the symbolic computation. With the... 相似文献
2.
Lee Bryan Tian Siyu Xiong Guoping Yang Ying Zhu Xiaoshan 《Journal of nanoparticle research》2022,24(4):1-15
Journal of Nanoparticle Research - Polycrystalline metallic copper nanoparticle samples with the average particle sizes ranging from 53 to 80 nm were controllably prepared by the wet... 相似文献
3.
Nonlinear Dynamics - To describe the particular mechanical behaviors of beams with both uniform and non-uniform cross sections, such as the bidirectional bending, torsion-bending coupling, the... 相似文献
4.
Xu Yifan Zhang Hehe Ding Tangjing Tian Ruiqi Sun Dongmei Wang Ming-Sheng Zhou Xiaosi 《中国科学:化学(英文版)》2022,65(9):1807-1816
Science China Chemistry - Due to their enormous potential for large-scale energy storage, rechargeable potassium-ion batteries have been widely researched and developed. However, the drastic volume... 相似文献
5.
Theoretical and Mathematical Physics - We theoretically calculate general higher-order soliton solutions of the space-shifted parity–time-symmetric nonlocal multicomponent nonlinear... 相似文献
6.
Theoretical and Mathematical Physics - Starting from a $$5\times 5$$ local matrix $$\bar\partial$$ -problem, we successfully use the $$\bar\partial$$ -dressing method to derive a hierarchy of... 相似文献
7.
Molecular Diversity - Epidermal growth factor receptor (EGFR) has received widespread attention because it is an important target for anticancer drug design. Mutations in the EGFR, especially the... 相似文献
8.
Nonlinear Dynamics - Under investigation in this paper is the $$(3+1)$$ -dimensional B-type Kadomtsev–Petviashvili–Boussinesq (BKP–Boussinesq) equation, which can display the... 相似文献
9.
De-en Han Yanmei Shi Ping Tian Hengchao Wei Mingsan Miao Xiu-min Li 《Biomedical chromatography : BMC》2020,34(7):e4838
A rapid and sensitive method was developed and validated for the quantitative determination of xanthopurpurin (XPP) in rat plasma using ultra-performance liquid chromatography-electrospray ionization-Orbitrap mass spectrometry. XPP inhibits IgE production and prevents peanut-induced anaphylaxis. The XPP and emodin (internal standard) were determined in negative ion mode with m/z 239.0350 → 211.0400 and 269.0455 → 241.0507, respectively. The separation process was achieved using an ACQUITY UPLC HSS T3 column with acetonitrile and 0.1% formic acid in water (85:15). The linear range was 0.5–100 ng/mL, and the correlation coefficient (r2) was > 0.993. The inter-day and intra-day precision was within an acceptable range of 15%. The extraction recovery and matrix effect were 78.9–87.2% and 94.3–98.5%, respectively. Under different conditions, the XPP was stable in the range of 5.6–10.6%. This method was successfully applied to study the pharmacokinetics of XPP with an oral dose of 10.0 mg/kg and intravenous dose of 2.0 mg/kg in rats. The absolute oral bioavailability of XPP was 4.6%. 相似文献
10.
Highly Effective Detection of Amitraz in Honey by Using Surface-Enhanced Raman Scattering Spectroscopy Coupled with Chemometric Methods 下载免费PDF全文
Xin-ming Nie Jing Wang Xun Wang Ya-ping Tian Si Chen Zhou-yang Long Cheng-hua Zong 《化学物理学报(中文版)》2019,32(4):444-450
As an effective and universal acaricide, amitraz is widely used on beehives against varroasis caused by the mite Varroa jacobsoni. Its residues in honey pose a great danger to human health. In this study, a sensitive, rapid, and environmentally friendly surface-enhanced Raman spectroscopy method (SERS) was developed for the determination of trace amount of amitraz in honey with the use of silver nanorod (AgNR) array substrate. The AgNR array substrate fabricated by an oblique angle deposition technique exhibited an excellent SERS activity with an enhancement factor of ∽107. Density function theory was employed to assign the characteristic peak of amitraz. The detection of amitraz was further explored and amitraz in honey at concentrations as low as 0.08 mg/kg can be identified. Specifically, partial least square regression analysis was employed to correlate the SERS spectra in full-wavelength with Camitraz to afford a multiple-quantitative amitraz predicting model. Preliminary results show that the predicted concentrations of amitraz in honey samples are in good agreement with their real concentrations. Compared with the conventional univariate quantitative model based on single peak’s intensity, the proposed multiple-quantitative predicting model integrates all the characteristic peaks of amitraz, thus offering an improved detecting accuracy and anti-interference ability. 相似文献