全文获取类型
收费全文 | 99篇 |
免费 | 1篇 |
专业分类
化学 | 33篇 |
晶体学 | 1篇 |
力学 | 6篇 |
数学 | 11篇 |
物理学 | 49篇 |
出版年
2021年 | 3篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2012年 | 4篇 |
2011年 | 2篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 2篇 |
2005年 | 5篇 |
2004年 | 4篇 |
2002年 | 4篇 |
2001年 | 7篇 |
2000年 | 11篇 |
1999年 | 7篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 6篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有100条查询结果,搜索用时 7 毫秒
51.
Harold Burton Andre Wineland Mousumi Bhattacharya Joyce Nicklaus Keith S Garcia Jay F Piccirillo 《BMC neuroscience》2012,13(1):3
Background
The objective was to examine functional connectivity linked to the auditory system in patients with bothersome tinnitus. Activity was low frequency (< 0.1 Hz), spontaneous blood oxygenation level-dependent (BOLD) responses at rest. The question was whether the experience of chronic bothersome tinnitus induced changes in synaptic efficacy between co-activated components. Functional connectivity for seed regions in auditory, visual, attention, and control networks was computed across all 2 mm3 brain volumes in 17 patients with moderate-severe bothersome tinnitus (Tinnitus Handicap Index: average 53.5 ± 3.6 (range 38-76)) and 17 age-matched controls. 相似文献52.
Munshi G Mustafa Sudhir Raniwala T Awes B Rai RS Bhalerao JG Contreras RV Gavai SK Ghosh P Jaikumar GC Mishra AP Mishra H Mishra B Mohanty J Nayak J-Y Ollitrault SC Phatak L Ramello R Ray PK Sahu AM Srivastava DK Srivastava VK Tiwari 《Pramana》2006,67(5):961-981
This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and
work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported. 相似文献
53.
54.
Poli T Chiantore O Nervo M Piccirillo A 《Analytical and bioanalytical chemistry》2011,400(4):1161-1171
Mid-IR fiber-optic reflectance spectroscopy (FORS) is a totally noninvasive infrared analytical technique allowing the investigation
of artworks without the need for any sampling. The development and optimization of this analytical methodology can provide
a tool that is capable of supporting conservators during the first steps of their interventions, yielding fast results and
dramatically reducing the number of samples needed to identify the materials involved. Furthermore, since reflection IR spectra
suffer from important spectral anomalies that complicate accurate spectral interpretation, it is important to characterize
known reference materials and substrates in advance. This work aims to verify the possibility of investigating and identifying
the most widely used wood finishes by means of fiber-optic (chalcogenide and metal halides) mid-infrared spectroscopy. Two
historically widely employed wood finishes (beeswax, shellac) and two modern ones (a hydrogenated hydrocarbon resin and a
microcrystalline wax) were investigated in an extended IR range (from 1000 to 6000 cm−1) with reflectance spectroscopy and with FORS. The broad spectral response of the MCT detector was exploited in order to include
overtones and combination bands from the NIR spectral range in the investigation. The reflectance spectra were compared with
those collected in transmission mode in order to highlight modifications to shapes and intensities, to assign absorptions,
and finally to select “marker” bands indicating the presence of certain finishing materials, even when applied onto a substrate
such as wood, which shows many absorptions in the mid-infrared region. After the characterization, the different products
were applied to samples of aged pear wood and investigated with the same techniques in order to check the ability of mid-IR
FORS to reveal the presence and composition of the product on the wooden substrate. 相似文献
55.
We study existence and regularity of solutions of noncoercive variational inequalities. 相似文献
56.
Summary Ultrafine Si, Si3N4, SiC and silicon oxynitride powders have been produced by irradiating gas-phase reactants by means of a CO2 laser. The mechanism of SiH4 CO2 laser-induced absorption and dissociation is discussed on the basis of the results of the spectral and time-resolved measurement
of fragment chemiluminescence. The role played by the SiH2 radical in the powder formation is investigated. The quality of Si, Si3N4, SiC and silicon oxynitride powders is checked by means of several off-line diagnostics (IR spectroscopy, X-ray diffraction
at wide and small angle, BET analysis). The possibility of controlling powder stoichiometry and doping from the gas-phase
reactant concentration is discussed. 相似文献
57.
Hypergeometric-Gaussian modes 总被引:1,自引:0,他引:1
We studied a novel family of paraxial laser beams forming an overcomplete yet nonorthogonal set of modes. These modes have a singular phase profile and are eigenfunctions of the photon orbital angular momentum. The intensity profile is characterized by a single brilliant ring with the singularity at its center, where the field amplitude vanishes. The complex amplitude is proportional to the degenerate (confluent) hypergeometric function, and therefore we term such beams hypergeometric-Gaussian (HyGG) modes. Unlike the recently introduced hypergeometric modes [Opt. Lett. 32, 742 (2007)], the HyGG modes carry a finite power and have been generated in this work with a liquid-crystal spatial light modulator. We briefly consider some subfamilies of the HyGG modes as the modified Bessel Gaussian modes, the modified exponential Gaussian modes, and the modified Laguerre-Gaussian modes. 相似文献
58.
59.
60.