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991.
Y. Watanabe H. Yamaguchi M. Hashinokuchi K. Sawabe S. Maruyama Y. Matsumoto K. Shobatake 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(1):103-109
The scattering of a hyperthermal Xe from a graphite (0001) surface
has been studied using a molecular beam-surface scattering technique
and molecular dynamics (MD) simulations.
The angular and velocity distributions of scattered Xe atoms
were measured at incidence energies from 0.45 to 3.5 eV,
three incidence angles of 15°, 35° and 60°
and the surface temperatures of 300 K and 550 K.
The observed time-of-flight spectra exhibit a sharp velocity distribution
with only one velocity component, which is ascribed
to the direct inelastic scattering process.
The angle-resolved energy ratios of the mean final translational energy
over the mean incidence energy Ef/Ei agree well
with those predicted based on the assumption of the conservation
of the momentum parallel to the surface.
The Hard-Cube model, where the mass of the cube is approximately 310 u,
has reproduced the angle-resolved flux distributions of scattered Xe atoms.
In the Hard-Cube model
almost 80% of the normal component of the incidence translational energy is found
to be lost in collision.
The MD simulations reproduce well the experimental results
by using the Brenner potential for intralayer C atoms
and a Lennard-Jones potential for interlayer C–C pair interactions. 相似文献
992.
The adsorption of 4-cyanopyridine (PyCN) on Ag electrode has been studied by surface-enhanced Raman scattering. The Raman band of the CN group is at 2240 or 2100 cm?1; it appears in various ranges of potential. When a series of potentials was applied stepwise to the electrode, the growing and vanishing of both bands was monitored by an optical multichannel analyzer with a time resolution 1 s or less. Some information about the kinetics of the adsorption and desorption of CN group and about the adsorption geometry of PyCN on the electrode was obtained. 相似文献
993.
L. Roca C. Hanhart E. Oset U. -G. Meißner 《The European Physical Journal A - Hadrons and Nuclei》2006,27(3):373-380
The Λ(1520)-resonance has been recently studied in a unitarized coupled-channel formalism with πΣ(1385), KΞ(1530), ˉN and πΣ as constituents blocks. We provide a theoretical study of the predictions of this model in physical observables of
the pp → pK+K-p and pp → pK+π0π0Λ reactions. In particular, we show that the ratio between the π0π0Λ and K-p mass distributions can provide valuable information on the ratio of the couplings of the Λ(1520)-resonance to πΣ(1385) and
ˉN than the theory predicts. Calculations are done for energies which are accessible in an experimental facility like COSY at
Jülich or the developing CSR facility at Lanzhou. 相似文献
994.
Supriya Mukherjee A. Ghose Choudhury A. Roy Chowdhury 《International Journal of Theoretical Physics》2006,45(4):820-834
We investigate the relation between the local variables of a discrete integrable lattice system and the corresponding separation variables, derived from the associated spectral curve. In particular, we have shown how the inverse transformation from the separation variables to the discrete lattice variables may be factorized as a sequence of canonical transformations. 相似文献
995.
Aleksander Filip Żarnecki 《Pramana》2007,69(5):937-941
The CAIN simulation program was used to study the outgoing beam profile for the photon collider at ILC. The main aim of the
analysis was to verify the feasibility of the photon linear collider running with 20 mrad electron beam crossing angle. The
main problem is the distorted electron beam, which has to be removed from the interaction region. It is shown that with a
new design of the final dipole, it should be possible to avoid large energy losses at the face of the magnet.
相似文献
996.
Hong Ping GUO Cheng Zhi HUANG Jian LING 《中国化学快报》2006,17(1):53-56
Light scattering submicroscopic particles such as metallic particles and particles of other composition have high-producing power and can be used as fluorescent analogs and tracers labels in clinical and biological applications1-3. Their light scattering … 相似文献
997.
离轴多层球对高斯波束的光散射 总被引:2,自引:2,他引:0
根据广义米氏理论,将入射的高斯波束按矢量球谐函数展开,获得了波束因子(展开系数)gmn,TM和gmn,TE的一般表达式。应用gmn的局域近结果和散射系数anm和bnm的迭代公式与算法,研究了多层有耗介质球的光散射。讨论了波束宽度与球形粒子的尺寸和位置对散射系数和散射强度角分布的影响。 相似文献
998.
V. S. Zuev 《Journal of Russian Laser Research》2005,26(5):347-362
We have considered evanescent plane waves in structures with a layer of a substance with ε, μ < 0 and with a layer of a well-reflecting
metal, ε < 0, μ ≥ 1. Waves with increased amplitude as compared with the initial wave have been found to occur, due to which
evanescent waves with wave number as in the initial wave but with increased amplitude arise behind these layers. A composite
material with ε, μ < 0 at optical frequencies are proposed. Surface waves on a metal layer are considered in detail. It is
shown that surface waves with a sufficiently arbitrary wave number can be excited. It is also shown that, on very thin layers,
surface waves with wave number exceeding ten times that of a homogeneous plane wave in vacuum can be excited. Propagation
losses are calculated. For a silver layer, the wave path can be from 30 up to 100 wavelengths. Practical use in developing
techniques for optical transformations of short-wave surface waves in 2D space, similar to those in 3D space, are pointed
out. 相似文献
999.
C. Urlacher J. Dumas J. Serughetti J. Mugnier M. Munoz 《Journal of Sol-Gel Science and Technology》1997,8(1-3):999-1005
ZrO2 waveguides are prepared by the sol-gel process from a solution containing zirconiumn-propoxide and acetylacetone in propanol-2. Structural characterizations are investigated for different annealing temperatures using suitable techniques including Waveguide Raman Spectroscopy, Electron Microscopy and Atomic Force Microscopy. Films are amorphous at 300°C and the pure ZrO2 tetragonal crystalline phase appears beyond 400°C. Crystallized films present a dense, uniform and polycrystalline structure made up by randomly oriented nanocrystallites, the diameter of which increases from 38 Å at 400°C to 53 Å at 600°C. Waveguides are at least monomode TE0 at 632.8 nm. At this wavelength, optical losses are about, 0.8±0.2dB/cm for amorphous layers and increase up to 2.5±0.4 dB/cm for 600°C heat-treated waveguides. 相似文献
1000.
The pressure dependence of various phonon modes has been investigated through the ferro-paraelectric phase transition. Most
mode frequencies harden before levelling off above the phase transition. Mode Grüneisen parameters are estimated from the
pressure dependence of phonon frequencies. 相似文献