全文获取类型
收费全文 | 7583篇 |
免费 | 269篇 |
国内免费 | 52篇 |
专业分类
化学 | 5631篇 |
晶体学 | 71篇 |
力学 | 192篇 |
综合类 | 1篇 |
数学 | 947篇 |
物理学 | 1062篇 |
出版年
2023年 | 54篇 |
2022年 | 79篇 |
2021年 | 150篇 |
2020年 | 142篇 |
2019年 | 126篇 |
2018年 | 102篇 |
2017年 | 86篇 |
2016年 | 208篇 |
2015年 | 184篇 |
2014年 | 225篇 |
2013年 | 382篇 |
2012年 | 534篇 |
2011年 | 585篇 |
2010年 | 331篇 |
2009年 | 241篇 |
2008年 | 494篇 |
2007年 | 512篇 |
2006年 | 520篇 |
2005年 | 506篇 |
2004年 | 426篇 |
2003年 | 351篇 |
2002年 | 280篇 |
2001年 | 100篇 |
2000年 | 79篇 |
1999年 | 72篇 |
1998年 | 68篇 |
1997年 | 76篇 |
1996年 | 117篇 |
1995年 | 61篇 |
1994年 | 64篇 |
1993年 | 65篇 |
1992年 | 46篇 |
1991年 | 28篇 |
1990年 | 26篇 |
1989年 | 25篇 |
1988年 | 40篇 |
1987年 | 25篇 |
1986年 | 32篇 |
1985年 | 64篇 |
1984年 | 39篇 |
1983年 | 25篇 |
1982年 | 50篇 |
1981年 | 27篇 |
1980年 | 22篇 |
1979年 | 26篇 |
1978年 | 32篇 |
1977年 | 28篇 |
1976年 | 22篇 |
1975年 | 19篇 |
1974年 | 22篇 |
排序方式: 共有7904条查询结果,搜索用时 16 毫秒
111.
Jacobs PG Konrad-Martin D McMillan GP McDermott D Fausti SA Kagen D Wan EA 《The Journal of the Acoustical Society of America》2012,131(2):1296-1306
Stimulus-frequency (SF) otoacoustic emission (OAE) amplitude and the amplitude of medial olivocochlear (MOC) inhibition of SF OAEs for ipsilateral, contralateral and bilateral MOC reflex elicitors were recorded in six subjects with type 2 diabetes during a glucose tolerance test (GTT). Five of the six subjects were tested twice for a total of 11 trials and three subjects were tested in a control experiment. During the GTT experiment, the subjects' blood glucose was elevated from a euglycemic level below 150 mg/dL to a hyperglycemic level above 160 mg/dL following the consumption of a bolus of 80 g of sugar. A subset of three subjects were tested in a control experiment during which SF OAE and MOC reflex measurements were made while blood sugar levels remained constant within the euglycemic region. Mean SF OAE amplitudes were elevated following glucose consumption. A statistically significant increase in MOC inhibition amplitude was observed during elevated sugar levels for the 11 GTT trials. Maximum inhibition occurred about an hour after glucose consumption when blood glucose levels peaked. Results indicate that acute hyperglycemia influences efferent control of the cochlea in people with type 2 diabetes. 相似文献
112.
We derive universal relations for the rf spectroscopy of a two-dimensional Fermi gas consisting of two spin states interacting through an S-wave scattering length. The rf transition rate has a high-frequency tail that is proportional to the contact and displays logarithmic scaling violations, decreasing asymptotically like 1/(ω2ln2ω). Its coefficient is proportional to ln2'(a'(2D)/a(2D)), where a(2D) and a'(2D) are the two-dimensional scattering lengths associated with initial-state and final-state interactions. The clock shift is proportional to the contact and to ln(a'(2D)/a(2D)). If |ln(a'(2D)/a(2D))| > 1, the clock shift arises as a cancellation between much larger contributions proportional to ln2(a'(2D)/a(2D)) from bound-bound and bound-free rf transitions. 相似文献
113.
Alexandru Nedelcu Eric Costard Philippe Bois Xavier Marcadet 《Infrared Physics & Technology》2007,50(2-3):227-233
Recent results obtained on building blocks for future third generation infrared focal plane arrays (FPAs) are presented. Our approach concerning the FPA performance assessment and small pixels modelling is exposed. We also demonstrate the ability of the quantum well infrared photodetector technology to answer the needs for compact (20 μm pitch) polarimetric FPAs. Finally, we present our first results on mid-wave infrared detectors at wavelengths below 4.2 μm. 相似文献
114.
115.
The work function of hydrothermally synthesized UO2 and the implications for semiconductor device fabrication 下载免费PDF全文
Christopher Young James Petrosky J. Matthew Mann Eric M. Hunt David Turner Tony Kelly 《固体物理学:研究快报》2016,10(9):687-690
The photoelectric work function of nearly stoichiometric (111) and (100) hydrothermally grown UO2 was measured to be 6.28 ± 0.36 eV and 5.80 ± 0.36 eV, respectively. Candidate metals for electrical contacts are identified for both rectifying and non‐rectifying contacts based on work function, lattice compatibility, and electrical conductivity. 相似文献
116.
Kirill Arapov Kaarle Jaakkola Vladimir Ermolov Guy Bex Eric Rubingh Samiul Haque Henrik Sandberg Robert Abbel Gijsbertus de With Heiner Friedrich 《固体物理学:研究快报》2016,10(11):812-818
Despite the great promise of printed flexible electronics from 2D crystals, and especially graphene, few scalable applications have been reported so far that can be termed roll‐to‐roll compatible. Here we combine screen printed graphene with photonic annealing to realize radio‐frequency identification devices with a reading range of up to 4 meters. Most notably our approach leads to fatigue resistant devices showing less than 1% deterioration of electrical properties after 1000 bending cycles. The bending fatigue resistance demonstrated on a variety of technologically relevant plastic and paper substrates renders the material highly suitable for various printable wearable devices, where repeatable dynamic bending stress is expected during usage. All applied printing and post‐processing methods are compatible with roll‐to‐roll manufacturing and temperature sensitive flexible substrates providing a platform for the scalable manufacturing of mechanically stable and environmentally friendly graphene printed electronics.
117.
Design and performance of BOREAS,the beamline for resonant X‐ray absorption and scattering experiments at the ALBA synchrotron light source 下载免费PDF全文
Alessandro Barla Josep Nicolás Daniele Cocco Secundino Manuel Valvidares Javier Herrero-Martín Pierluigi Gargiani Jairo Moldes Claude Ruget Eric Pellegrin Salvador Ferrer 《Journal of synchrotron radiation》2016,23(6):1507-1517
The optical design of the BOREAS beamline operating at the ALBA synchrotron radiation facility is described. BOREAS is dedicated to resonant X‐ray absorption and scattering experiments using soft X‐rays, in an unusually extended photon energy range from 80 to above 4000 eV, and with full polarization control. Its optical scheme includes a fixed‐included‐angle, variable‐line‐spacing grating monochromator and a pair of refocusing mirrors, equipped with benders, in a Kirkpatrick–Baez arrangement. It is equipped with two end‐stations, one for X‐ray magnetic circular dichroism and the other for resonant magnetic scattering. The commissioning results show that the expected beamline performance is achieved both in terms of energy resolution and of photon flux at the sample position. 相似文献
118.
119.
120.