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991.
992.
本文介绍一种研究a-Si:H/a-SiN:H界面层电子积累特性的新方法,所用样品为Cr/a-SiN:H/a-Si:H/(n+)a-Si:H/AI.测试表明,a-Si:H/a-SiN:H界面是一个电子积累层,其电子面密度为3.2×10~(11)/cm~2,并且界面层中的电子面密度随外加电压的增加而线性增加。实验结果与理论分析相一致。 相似文献
993.
超声波清洗对LCD性能的影响的研究 总被引:1,自引:0,他引:1
研究了超声波清洗对液晶器件定向层性能的影响,结果表明:超声波的输出功率、液晶器件的形状与尺寸以及清洗时的放置方式均对定向层的划伤程度产生较大的影响。并在此基础上进行了理论计算,结合实验结果,分析了定向层划伤的原因。 相似文献
994.
995.
In physicochemical studies on the sea-surface microlayer (SML) in seawater, the main researches conducted were as follows:
(1) It was found that there is an objective layer of sudden change in physical and chemical properties between the SML and
the subsurface layer in seawater. (2) The SML thickness was determined and should be about 50±10 μm. (3) The Gibbs model of
the SML was extended, and the multilayer model of the SML was advanced. (4) The original-location method, which corresponds
with the traditional removal-location method, was founded and used to determine the SML thickness. The results obtained from
the two methods were almost identical. (5) An abnormal phenomenon was found when the Gibbs solution adsorption was applied
to the seawater system, the reason for which was discussed preliminarily. 相似文献
996.
提出了两种新的抑制Es层杂波的自适应对消算法,分别是频域瞬时值LMS算法和归一化频域瞬时值LMS算法。频域瞬时值LMS算法是利用辅助天线输出的Es层杂波瞬时值来估计主天线当前输出中的Es层杂波成分,可以更大程度上抑制Es层杂波。而归一化频域瞬时值LMS算法则是在频域瞬时值LMS算法的基础上增加归一化的过程,可以大大缩短自适应过程的收敛时间。 相似文献
997.
本文讨论如下边值问题:x=0是转向点(c(0)=0),而在x=-1处出现多重边界层现象.对不同层次采用不同的伸长变量,构造具有不同量级的边界层校正项,得到关于解的一致有效的渐近展开式和有关的余项估计. 相似文献
998.
异质结应变层的临界厚度的确定 总被引:1,自引:0,他引:1
简要介绍了异质结的临界厚度,叙述了计算临界厚度的两种理论和其实验值. 相似文献
999.
Summary The effect of surface mass flux on the non-Darcy natural convection over a horizontal flat plate in a saturated porous medium
is studied using similarity solution technique. Forchheimer extension is considered in the flow equations. The suction/injection
velocity distribution has been assumed to have power function form Bx
l
, similar to that of the wall temperature distribution Ax
n
, where x is the distance from the leading edge. The thermal diffusivity coefficient has been assumed to be the sum of the molecular
diffusivity and the dynamic diffusivity due to mechanical dispersion. The dynamic diffusivity is assumed to vary linearly
with the velocity component in the x direction, i.e. along the hot wall. For the problem of constant heat flux from the surface (n=1/2), similarity solution is possible when the exponent l takes the value −1/2. Results indicate that the boundary layer thickness decreases whereas the heat transfer rate increases
as the mass flux parameter passes from the injection domain to the suction domain. The increase in the thermal dispersion
parameter is observed to favor the heat transfer by reducing the boundary layer thickness. The combined effect of thermal
dispersion and fluid suction/injection on the heat transfer rate is discussed.
Received 7 December 1995; accepted for publication 7 January 1997 相似文献
1000.
The thickness of the altered layer created by ion bombardment of the 6H–SiC single crystal was determined by means of Auger electron spectroscopy (AES) depth profiling in conjunction with factor analysis. After pre-bombardment of the surface by argon ions with energies 1, 2 and 4 keV until the steady state, the depth profiles of the induced altered layers were recorded by sputtering with low energy argon ions of 300 eV. Since the position and shape of the carbon Auger peak depend on the perfection of the crystalline structure, they were used for depth profile evaluation by factor analysis. In this way the depth profiles of the damaged surface region could be estimated in dependence on the ion energy. As a result, the thickness of the altered layer of SiC bombarded with 1, 2 and 4 keV Ar ions using an incident angle of 80° as well as the corresponding argon implantation profile could be measured. 相似文献