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101.
102.
103.
Y. Marandet H. Capes L. Godbert-Mouret M. Koubiti J. Rosato R. Stamm 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,39(2):247-260
In this work we investigate the influence of low
frequency turbulence on Doppler spectral line shapes in magnetized
plasmas. Low frequency refers here to fluctuations whose typical
time scale is much larger than those characterizing the atomic
processes, such as radiative decay, collisions and charge exchange.
This ordering is in particular relevant for drift wave turbulence,
ubiquitous in edge plasmas of fusion devices. Turbulent fluctuations
are found to affect line shapes through both the spatial and time
averages introduced by the measurement process. The profile is
expressed in terms of the fluid fields describing the plasma.
Assuming the spectrometer acquisition time to be much larger than
the turbulent time scale, an ordering generally fulfilled in
experiments, allows to develop a statistical formalism. We proceed
by successively investigating the effects of density, fluid velocity
and temperature fluctuations on the Doppler profile of a spectral
line emitted by a charge exchange population of neutrals. Line
shapes, and especially line wings are found to be affected by ion
temperature or fluid velocity fluctuations, and can in some cases
exhibit a power-law behavior. These effects are shown to be
measurable with existing techniques, and their interpretation in
each particular case would rely on already existing tools. From a
fundamental point of view, this study gives some insights in the
appearance of non-Boltzmann statistics, such as Lévy statistics,
when dealing with averaged experimental data. 相似文献
104.
太阳光对液晶显示器件光学特性的影响 总被引:4,自引:0,他引:4
太阳光对液晶显示器件的影响主要表现在它对其液晶显示器件光稳定性和寿命的影响,从而引起液晶显示器件的迅速老化。通过用分光光度计测量经过不同时间太阳光辐照后液晶显示器件的光谱特性,研究长时间阳光辐照对液晶显示器件的光学性能的影响,分析其光学性能的变化。结果表明, B组普通计算器液晶显示器和C组电话液晶显示器两组液晶片的光学特性类似,品质较好;而A组台式计算器液晶显示器液晶片的老化问题明显比B, C两组严重,品质较差。液晶显示器件长时间受阳光辐照,液晶结构会相应发生变化,光学性能也发生相应变化,表现为液晶表面变黄发黑,其光谱透射特性明显下降。这与液晶材料及制作工艺有关。 相似文献
105.
We investigate the parameter dynamics of eigenvalues of Hamiltonians (‘level dynamics’) defined on symmetric spaces relevant to condensed matter and particle physics. In particular we: (1) identify the appropriate reduced manifold on which the motion takes place, (2) identify the correct Poisson structure ensuring the Hamiltonian character of the reduced dynamics, (3) determine the canonical measure on the reduced space, (4) calculate the resulting eigenvalue density. 相似文献
106.
Tom Kennedy 《Journal of statistical physics》2008,131(5):803-819
We simulate several models of random curves in the half plane and numerically compute the stochastic driving processes that
produce the curves through the Loewner equation. Our models include models whose scaling limit is the Schramm-Loewner evolution
(SLE) and models for which it is not. We study several tests of whether the driving process is Brownian motion, as it is for
SLE. We find that testing only the normality of the process at a fixed time is not effective at determining if the random
curves are an SLE. Tests that involve the independence of the increments of Brownian motion are much more effective. We also
study the zipper algorithm for numerically computing the driving function of a simple curve. We give an implementation of
this algorithm which runs in a time O(N
1.35) rather than the usual O(N
2), where N is the number of points on the curve. 相似文献
107.
一种用于电子纸的电泳液的显示性能研究 总被引:1,自引:0,他引:1
用有机颜料汉沙黄(P.Y.3)、苏丹黑和合适的稳定剂为原料配制了一种性能稳定的电泳显示液.分析了此电泳显示液中颜料微粒的带电机理及其影响因素,研究了在改变电压方向时反射光谱与吸收光谱的变化及其原因,光谱分析结果表明体系中存在的各种吸附使显示效果受到局限,反射谱与吸收谱的变化在表征器件的显示特性时呈现出一致性,器件的反射光强和反射率在不同波长上有区域选择性,同时对比度也有区域选择性,这决定了在监测器件的响应时应选择的波长范围以及可利用的光源.兼顾灵敏性和测试信号强度的需求,选用峰值波长为470 nm的蓝光二极管为光源,电泳槽的厚度为0.2 mm,用荧光光谱仪监测相同周期不同幅值脉冲电压作用下颜料微粒在493 nm波长处的反射光强的变化,并由示波器记录并输出反射光强随驱动电压的变化,还结合相关理论讨论了驱动电压对器件的反射光强和对比度的影响. 相似文献
108.
Panse S Dong L Burian A Carus R Schutkowski M Reimer U Schneider-Mergener J 《Molecular diversity》2004,8(3):291-299
Kinases represent one of the largest enzyme families and key regulatory proteins in the cell. Only a small subset of these enzymes has been characterised so far. We have prepared different types of phosphopeptide and peptide microarrays displaying peptides deduced from annotated human phosphorylation sites and cytoplasmic domains of all annotated human membrane proteins. This approach was enabled by fully-automated high throughput micro-scale synthesis of peptides by the SPOT technology combined with chemo-selective immobilisation on modified glass slides. The phosphopeptide microarrays displaying 2923 peptides in total have been used for the characterisation of commercially available generic anti-phosphopeptide antibodies. This enabled us to detect Abl kinase activity on a microarray with anti-phosphotyrosine antibodies yielding results comparable to those obtained from a radioactive assay. More than 13 000 peptides deposited on six glass slides were used to profile casein kinase 2 (CK2) using a radioactive assay, since no generic antibody for the reliable detection of serine or threonine phosphorylation could be identified. All previously identified substrates were detected in the microarray experiment. In order to confirm whether substrates on the microarray are substrates in solution phase assays, more than 700 peptides were synthesised and tested with CK2 in a solution phase assay. All substrates identified in the solution phase assay were also detected on the microarray. 相似文献
109.
Gjergj Dodbiba Hyun Seo ParkKatsunori Okaya Toyohisa Fujita 《Journal of magnetism and magnetic materials》2008
In this work, properties of a magnetorheological (MR) fluid, prepared by dispersing a mixture of two types of carbonyl iron powders (CIPs) of different sizes, in an ionic liquid (N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate) that is stable from 9 °C to ca. 300 °C, have been investigated. At first, the random packing density of the mixture was computed as function of mixing ratio of CIP, in order to find out the tendency of the variation. Next, several mixtures, all having the same weight, were prepared at various mixing ratios and dispersed in the ionic liquid, in order to experimentally find the most suitable mixing ratio of CIP. Then, the magnetic clusters of the synthesized MR fluids were observed by using a digital microscope equipped with two permanent magnets, whereas the MR properties were investigated by using a rotation viscometer equipped with a solenoid coil. The experimental results pointed out that the MR fluid with 60 wt% fraction of large particles exhibited the highest MR response. 相似文献
110.
In this paper, we propose a method that controls the depth of the three-dimensional (3D) object existing over the depth-of-focus in integral imaging. The depth control method is performed only in a computer by synthesizing the intermediate sub-images between original sub-images obtained by transforming the captured elemental images. In the reconstruction process, we can obtain reconstructed 3D images with the better image quality within depth-of-focus than that reconstructed over the depth-of-focus. To demonstrate the feasibility of our method, optical and computational experiments are carried out and its results are presented. 相似文献