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991.
蓝色铬膜层的电沉积机理 总被引:1,自引:0,他引:1
本文通过对蓝色铬膜层的XPS分析及电化学方法研究了该膜层的沉积过程。结果表明,整个膜层可分为:120nm厚的交界层(主要成分是Cr和基底Ni),250nm厚的中间层(Cr_2O_3,Ct和CtSe,后者决定了膜层呈蓝色),以及100nm厚的表面层(吸附的Cr(Ⅵ)、Cr(Ⅲ),SeO_4~(2-)和Se),对电沉积历程和机理进行了探讨。 相似文献
992.
Langmuir-Blodgett (LB) films occupy a unique niche at the crossroads of materials science, complex fluids, and biophysics. They have many similarities to inorganic epitaxial films due to the layer by layer deposition process; however, the amphiphilic nature of the constituent molecules provides the connection to lyotropic liquid crystals and membranes. A great deal is known about LB film structure and thermodynamic behavior; both from classical studies as well as from recent experiments using sophisticated characterization techniques such as synchrotron X-ray scattering and scanning probe microscopy. This article summarizes the current understanding of these systems from a physical/structural point of view. Included are discussions of the deposition process, the layered nature of LB films, intralayer molecular packing, defects, stability, and phase transitions. 相似文献
993.
Oxidation of vanadium metal surfaces at room temperature by low-energy oxygen ion beams is investigated by X-ray photoelectron spectroscopy (XPS). It is observed that ion-beam irradiation of clean V results in formation of thin oxide layer containing vanadium in oxidation states corresponding to VO, V2O3, VO2 and V2O5 oxides. The composition of the products of ion-beam oxidation depends markedly on oxygen ion fluence. The results of angle-resolved XPS measurements are consistent with a structure of oxide film with the outermost part enriched in V2O5 and VO2 oxides and with V2O3 and VO oxides located in the inner region of the oxide layer. 相似文献
994.
三元复合表面膜反射光谱的计算 总被引:1,自引:1,他引:0
将二元的金属-介质非均匀复合物的等效介质理论推广到三元的情况,并由此计算出两种铝阳极氧化着色谱试样的反射谱。与实验结果对比可看出,计算曲线与实验曲线大致相符,表明该计算方法在一定范围和条件下的适用性,从而为多元复合表面材料光特性的理论研究提供了一种可行的方法。 相似文献
995.
The determination of film thickness is of prime importance in the quality assurance of coated pharmaceutical preparations. The rapid measurement of this parameter is problematic for multi-particulate pellet systems. The aim of this study was to apply the Raman spectroscopic method for the determination of the thickness of polymer coating on pellets. The change of Raman intensity was compared with measured film thickness, which was calculated from the change of the geometric parameters of the pellets, measured with an image-analyzing system. The results revealed that despite some difficulties Raman spectroscopy is a suitable method for the fast and accurate determination of film thickness on multi-particulate systems. 相似文献
996.
kos Nemcsics 《Applied Surface Science》2002,190(1-4):294-297
In this work, we have looked for the correlation between the observed decay of reflection high-energy electron diffraction intensity oscillation and the critical layer thickness in the case of strained InxGa1−xAs/GaAs heterojunctions. The value of deading time constant of oscillation depends on the mismatch and on growth parameters, too. The decay of oscillation was described by two deading time constants which are responsible for the influences of the parameters mentioned above. The critical layer thickness was valued from the deading time constant responsible for the influence of mismatch only. The critical layer thickness determined this way shows good agreement with the theoretical model. 相似文献
997.
Regimes of superfluid-helium boiling on structural-steel spheres 4.8 and 6.0 mm in diameter, with heaters installed inside, are examined. Experimental data on the evolution of vapor films formed on the
spherical surfaces are obtained.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 6, pp. 78–84, November–December, 2006. 相似文献
998.
蓝色显示材料及器件的研究 总被引:3,自引:1,他引:2
用H2和CS2还原法制备Ce:SrS发光材料,分析了两种方法对材料的结构及发光特性的影响,得到了最高亮度为950cd/m^2(1000Hz)的Ce:SrS薄膜电致发光(TFEL)器件;用高温固相法得到Ce:SrGa2S4荧光粉,用射频溅射沉积的Ce:SrGa2S4薄膜在600℃以上、H2S气氛下快速热处理可以改善薄膜结晶性能,提高杂质激发峰强度,得到好的光致发光(PL)发光性能,以陶瓷片作为基片同 相似文献
999.
偶氮聚合物薄膜的全光极化研究 总被引:4,自引:0,他引:4
报告了分散红共聚物膜HMMM-DR1,HMMM-DR19和偶氮侧链聚合物膜PCN6和PCN2的合成和制备, 并以HMMM-DR1和PCN6为代表比较研究了这两种具有不同吸收性质材料的全光极化特性,研究了他们的实时极化和弛豫过程,对他们的全光极化性质作了最基本的表征.研究了倍频光吸收对薄膜光极化效率的影响,讨论了偶氮聚合物材料光诱导二阶非线性极化率的效率和倍频光透射率之间的折衷关系,这对实用化的全光器件的研制是至关重要的.实验确证了在PCN6薄膜中实现了准相位匹配.对厚膜中光诱导二阶非线性极化率的弛豫抑制效应作出解释. 相似文献
1000.
The deformation and fracture behavior under uniaxial tension was characterized for P(VDF‐TrFE) 68/32 mol % copolymer films prepared under two different processing conditions. It was found that the copolymer films prepared by solution casting and then annealing show a typical polymeric brittle fracture feature. For the copolymer films prepared by stretching the solution‐cast films and then annealing process, a typical linearly strengthening stage occurs in the stress–strain curve after yielding, and the polymer film samples fracture at a much larger maximum strain and a higher tensile strength than those prepared by the former process. SEM observation and XRD analysis were carried out to examine the morphology and microstructure change during uniaxial tension. The results show that for the stretched film samples, the polymer chains undergo slipping or further reorientation during uniaxial tension, causing the increase of the peak intensity in the X‐ray diffraction pattern. For the directly annealed ones, no yielding phenomenon is observed and there is no apparent X‐ray diffraction intensity change. It was suggested that the highly‐oriented fibril structure of the stretched film samples contributes to the linearly strengthening stage after yielding in the stress–strain curve. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3255–3260, 2005 相似文献