全文获取类型
收费全文 | 90篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
化学 | 19篇 |
力学 | 4篇 |
数学 | 22篇 |
物理学 | 47篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 1篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 6篇 |
2004年 | 6篇 |
2003年 | 2篇 |
2002年 | 7篇 |
2001年 | 6篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1976年 | 4篇 |
1968年 | 1篇 |
排序方式: 共有92条查询结果,搜索用时 31 毫秒
1.
Chae Oh B. Yeddala Munaiah Lucht Brett L. 《Journal of Solid State Electrochemistry》2022,26(9):2005-2011
Journal of Solid State Electrochemistry - A thorough understanding of the lithium deposition behavior will facilitate the commercialization of lithium metal anodes. Despite enormous effort, an... 相似文献
2.
3.
We demonstrate reversible photoinduced in situ reorientation of low molecular mass liquid crystals (LCs) by means of photoaddressable polymers (PAPs). These polymers contain mesogenic azobenzene side chains optimized to reorient cooperatively and effectively upon illumination with polarized light. Various low molecular mass LCs were introduced between two PAP layers and these sandwich devices were tested with respect to stability and reversibility of photoinduced orientation. Dissolution of the PAP layer by the low molecular mass LC was observed for several material combinations and systematically investigated. Different anisotropic dyes were added as fluorescence markers in order to monitor the photoinduced LC orientation. With an optimized material combination, more than 10 reversible reorientation processes could be realized with polarized light of either 514 or 405 nm wavelength, without any reduction in alignment quality. Further, microscopic polarized fluorescence patterns could be produced and erased within short exposure times. 相似文献
4.
Plasmas generated during incipient laser ablation of aluminum in air were studied using emission spectroscopy. A plasma emission
model was developed, invoking one-dimensional radiative transfer, to describe the observed emission spectra, while taking
into account the effects of continuum radiation. Theoretical spectra were calculated and compared to experimental spectra
in the range 387–406 nm. Satisfactory agreement was found between the experimental and predicted spectra, especially at delay
times of 30–200 ns, thus providing plasma temperatures and electron number densities as functions of delay time and laser
irradiance (1.8–8.0 GW/cm2). In general, both the plasma temperature and electron number density rise at greater laser irradiances but drop at increasing
delay times, with a more rapid drop for delay times less than 60 ns.
PACS 42.62.Fi; 52.25.-b 相似文献
5.
This paper reports on recent progress in the theory of multiplicative arithmetic semigroups, which has been initiated by John
Knopfmacher's work on abstract analytic number theory. In particular, it deals with abstract versions of the mean-value theorems
of Delange, of Wirsing, and of Halász for multiplicative functions on arithmetic semigroups G with Axiom A . The Turán Kubilius
inequality is transferred to G , and methods developed by Rényi, Daboussi and Indlekofer, Lucht and Reifenrath are utilized.
As byproduct a new proof of the abstract prime number theorem is obtained.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
Ohne Zusammenfassung 相似文献
7.
A theoretical analysis of coherent anti-Stokes Raman scattering (CARS) spectroscopy of gas-phase resonances using femtosecond lasers is performed. The time-dependent density matrix equations for the femtosecond CARS process are formulated and manipulated into a form suitable for solution by direct numerical integration (DNI). The temporal shapes of the pump, Stokes, and probe laser pulses are specified as an input to the DNI calculations. It is assumed that the laser pulse shapes are 70 fs Gaussians and that the pulses are Fourier-transform limited. A single excited electronic level is defined as an effective intermediate level in the Raman process, and transition strengths are adjusted to match the experimental Raman polarizability. The excitation of the Raman coherence is investigated for different Q-branch rotational transitions in the fundamental 2330 cm(-1) band of diatomic nitrogen, assuming that the pump and Stokes pulses are temporally overlapped. The excitation process is shown to be virtually identical for transitions ranging from Q2 to Q20. The excitation of the Raman coherences is also very efficient; for laser irradiances of 5x10(17) W/m2, corresponding approximately to a 100 microJ, 70 fs pulse focused to 50 microm, approximately 10% of the population of the ground Raman level is pumped to the excited Raman level during the impulsive pump-Stokes excitation, and the magnitude of the induced Raman coherence reaches 40% of its maximum possible value. The theoretical results are compared with the results of experiments where the femtosecond CARS signal is recorded as a function of probe delay with respect to the impulsive pump-Stokes excitation. 相似文献
8.
N. Chai W.D. Kulatilaka S.V. Naik N.M. Laurendeau R.P. Lucht J.P. Kuehner S. Roy V.R. Katta J.R. Gord 《Applied physics. B, Lasers and optics》2007,88(1):141-150
We report the application of electronic-resonance-enhanced coherent anti-Stokes Raman scattering (ERE-CARS) for measurements
of nitric oxide concentration ([NO]) in three different atmospheric pressure flames. Visible pump (532 nm) and Stokes (591 nm)
beams are used to probe the Q-branch of the Raman transition. A significant resonance enhancement is obtained by tuning an
ultraviolet probe beam (236 nm) into resonance with specific rotational transitions in the (v’=0, v”=1) vibrational band of
the A2Σ+–X2Π electronic system of NO. ERE-CARS spectra are recorded at various heights within a hydrogen-air flame producing relatively
low concentrations of NO over a Hencken burner. Good agreement is obtained between NO ERE-CARS measurements and the results
of flame computations using UNICORN, a two-dimensional flame code. Excellent agreement between measured and calculated NO
spectra is also obtained when using a modified version of the Sandia CARSFT code for heavily sooting acetylene-air flames
(φ=0.8 to φ=1.6) on the same Hencken burner. Finally, NO concentration profiles are measured using ERE-CARS in a laminar,
counter-flow, non-premixed hydrogen-air flame. Spectral scans are recorded by probing the Q1 (9.5), Q1 (13.5) and Q1 (17.5) Raman transitions. The measured shape of the [NO] profile is in good agreement with that predicted using the OPPDIF
code, even without correcting for collisional effects. These comparisons between [NO] measurements and predictions establish
the utility of ERE-CARS for detection of NO in flames with large temperature and concentration gradients as well as in sooting
environments.
PACS 07.88.+y; 42.62.Fi; 42.65.Dr 相似文献
9.
Helge Glö ckner Lutz G. Lucht Stefan Porubsky 《Proceedings of the American Mathematical Society》2007,135(6):1619-1629
In the -algebra of arithmetic functions , endowed with the usual pointwise linear operations and the Dirichlet convolution, let denote the convolution power with factors . We investigate the solvability of polynomial equations of the form with fixed coefficients . In some cases the solutions have specific properties and can be determined explicitly. We show that the property of the coefficients to belong to convergent Dirichlet series transfers to those solutions , whose values are simple zeros of the polynomial . We extend this to systems of convolution equations, which need not be of polynomial-type.
10.
Ohne Zusammenfassung 相似文献