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11.
The switchable optical properties of Pd-protected RCo2-type Ho0.6Mm0.4Co2 alloy thin films have been investigated in a KOH electrolyte. The reversible optical switching has been carried out simultaneously by measuring transmitted light through the thin film during electrochemical charging–discharging of hydrogen. The dependence of switching speed and cyclic durability of the film on the charging and discharging current density as well as concentration of KOH electrolyte has been studied. In addition, cyclic voltammetric measurements have been performed to examine the hydride formation and decomposition reactions.  相似文献   
12.
根据PET薄膜的特点和高分子熔融态流动理论,分析了挤出回收用螺杆的各段结构,及螺杆参数选择,设计出大长径比、深槽、双排气、高效专用螺杆。  相似文献   
13.
The breakdown processes of oil films under quasi-static loading have been investigated by using a newly developed steel-oil-mercury system. The relationship between the thickness and breakdown ratio of a hexadecane film is represented by a single master curve independently of the indentation speed, indentation load, and temperature. The master curve shows that the breakdown process of hexadecane includes two stages; one is the decrement of the thickness without breakdown and the other is the decrement of the thickness with a drastic progress of breakdown. By solving a small amount of fatty acid in hexadecane, the thickness increases and the breakdown ratio decreases noticeably; a multilayer residual film supporting normal load is formed between two metal surfaces. Experiments at different temperatures reveal a negative relationship between the temperature and thickness of residual film, which indicates that the residual film is organized by physical interaction rather than chemical interaction. At least under a lower concentration, the residual film appears to consist of not only fatty acid molecules but also hexadecane molecules.  相似文献   
14.
基于光敏自组装多层膜的液晶光控取向膜   总被引:1,自引:1,他引:0  
采用layer-by-layer(LBL)的方法,将基板依次在具有光敏双键的季铵盐水溶液和聚乙烯基苯磺酸钠水溶液中浸泡,石英基板表面形成了自组装多层沉积膜。经线性偏振紫外光辐照后,LBL多层膜表现出明显的紫外吸收各向异性。将两片带有各向异性薄膜的基板做成平行液晶器件。在正交的偏光显微镜下观察,发现取得均一、稳定的取向效果。该种光控取向膜有望用作LCoS微显示的取向层。  相似文献   
15.
TiN coatings were deposited on polished substrates of W18Cr4V high speed steel by means of vacuum arc ion plating. The effect of cerium on adhesion between TiN coating and substrate was studied. The microstructures and composition of TiN coatings were also investigated by means of scanning electron microscope (SEM), Auger electron spectroscopy (AES), and X-ray diffraction (XRD) technique. It was found that cerium is an effective modifying agent and the addition of suitable amount of cerium to TiN coatings can produce relatively excellent properties such as micro-hardness, wear resistance, oxidation resistance and porosity. The experimental results show that the added cerium in TiN coatings makesa contribution to form the preferred direction along with a (111 ) or (222) close packed face, which may be one of the reasons that improves some properties mentioned above.  相似文献   
16.
In this paper, we examine, both experimentally and theoretically, the kinetics of formation and microstructure of product phases in thin film reactions, using the Nb/Al and Ti/Al systems as our prototypes. The results of calorimetry and microscopy studies are interpreted using simple kinetic and morphology models. In particular, the kinetic models employed here focus on the nucleation and growth components of the phase formation process and the morphology models provide a starting point for the classification of product grain structures. An erratum to this article is available at .  相似文献   
17.
王浩 《真空与低温》1997,3(2):70-73
提出了溅射-气体-聚集共沉积制备金属/金属(介质)复合团簇镶嵌薄膜的新方法,并利用该方法成功地在方华膜衬底上制备了系列Fe/Ag及CaF2复合团簇镶嵌薄膜样品。透射电镜分析结果表明,样品中Fe(Cu)团簇都较好地镶嵌于Ag(CaF2)基质中,其结构为两种材料的多晶共存形态。进一步分析发现,与块材相比,Fe/Ag样品中Fe团簇晶格常数呈现出不同程度的收缩,而Cu/CaF2样品中Cu团簇晶格常数则呈现出不同程度的膨胀。运用附加压力的模型对该现象进行了解释。  相似文献   
18.
与普通爆轰不同,粉尘薄膜爆轰波前氧化剂与燃料处于分离状态.由于激波作用下壁面燃料的注入才于壁面附近形成燃烧的粉尘云,燃烧释放的热使激波自持形成粉尘薄膜爆轰。本文在长2、8m,横截面20mm×20mm的方型水平激波管中对此类爆轰进行了实验研究.并根据作者建立的模型对其二维结构进行了数值模拟。  相似文献   
19.
薄Si膜对基底表面粗糙度的影响   总被引:8,自引:3,他引:5  
利用ZYGO光学干涉测量仪,散射积分测量法观测了光学元件表面均方根粗糙度.详细分析了薄Si膜对基底均方根粗糙度的影响,由此认为薄膜并不总是复制基底表面的粗糙度,结果出现了薄膜降低表面粗糙度的现象.提出了一定厚度范围的薄Si膜的表面粗糙度存在着一个稳定值的新设想.  相似文献   
20.
A mathematical model of evaporation process from a laminar falling liquid film on a vertical plate of constant temperature is presented. The model is developed with and without interfacial shear stress due to the vapor flow at the liquid film surface. The vapor pressure drop, vapor exit velocity and cooling rate are calculated for different liquid mass flow values. It is shown that lower liquid mass flow produces higher cooling rate. The results also show that the interfacial shear stress has a considerable negative effect on the cooling rate. It is proved that there exists an optimum distance between the plates, which gives the maximum volumetric cooling rate.  相似文献   
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