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排序方式: 共有659条查询结果,搜索用时 31 毫秒
1.
《Ceramics International》2021,47(19):27342-27350
The (CrAlTiNbV)Nx coatings are fabricated by controlling the substrate bias via magnetron sputtering method. Under low substrate bias, the coating tends to form a loose columnar crystal structure with (200) preferred orientation. However, when the substrate bias increases, the coating transforms into a dense nanocrystalline structure, and the (111) orientation is enhanced. As the substrate bias increases, the residual stress and hardness of the coating gradually increase, while the adhesion strength decreases slightly. Friction tests show that the coating possesses the lowest average friction coefficient (about 0.06) and wear rate (8.7 × 10-9 mm3/N·m) in 4050# aviation lubricant, which is achieved under the substrate bias of -96 V and -126 V, respectively. 相似文献
2.
We have improved the electronic properties of narrow-bandgap (Tauc gap below 1.5 eV) amorphous-silicon germanium alloys (a-SiGe:H) grown by hot-wire chemical vapor deposition (HWCVD) by lowering the substrate temperature and deposition rate. Prior to this work, we were unable to grow a-SiGe:H alloys with bandgaps below 1.5 eV that had photo-to-dark conductivity ratios comparable with our plasma-enhanced CVD (PECVD) grown materials [B.P. Nelson et al., Mater. Res. Soc. Symp. 507 (1998) 447]. Decreasing the filament diameter from our standard configuration of 0.5 mm to 0.38 or 0.25 mm provides first big improvements in the photoresponse of these alloys. Lowering the substrate temperature from our previous optimal temperatures (Tsub starting at 435 °C) to at 250 °C provides additional photo-to-dark conductivity ratio increasing by two orders of magnitude for growth conditions containing 20–30% GeH4 in the gas phase (relative to the total GeH4+SiH4 flow). 相似文献
3.
基体温度对磁控溅射沉积ZAO薄膜性能的影响 总被引:8,自引:2,他引:6
利用中频交流磁控溅射方法 ,采用氧化锌铝陶瓷靶材 [w(ZnO) =98%、w(Al2 O3 ) =2 % ]制备了ZAO(ZnO∶Al)薄膜 ,观察了基体温度对ZAO薄膜的晶体结构、电学和光学性能的影响 ,采用X射线衍射仪对薄膜的结构进行了分析 ,采用光学分度计和电阻测试仪测量了薄膜的光学、电学特性 ,采用霍尔测试仪测量了薄膜的载流子浓度和霍尔迁移率。结果表明 :沉积薄膜时的基体温度对薄膜的结构、结晶状况、可见光透射率以及导电性有较大的影响。当基体温度为 2 5 0℃ ,Ar分压为 0 8Pa时 ,薄膜的最低电阻率为 4 6× 10 -4Ω·cm ,方块电阻为 35Ω时 ,可见光 (λ =5 5 0nm)透射率高达 92 0 %。 相似文献
4.
文章报道了用分子束外延(MBE)法在600℃和650℃下,在Si掺杂的GaAs衬底的(311)A和(311)B面上成功地生长了高质量的AlxGa1-As/GaAs单量子阱材料。计算了光荧光(PL)峰值能量,并与实验作了比较。讨论了(311)A和(311)B面上的不同生长特性。 相似文献
5.
Li-Tang Yan 《Polymer》2006,47(18):6472-6480
The surface-directed spinodal decomposition (SDSD) of polymer binary mixture with different values of surface potential is numerically simulated in three-dimension (3D) by cell dynamic systems (CDS). Furthermore, the growth laws of the wetting layer are theoretically analyzed by the current equation and the dynamical scaling. The results show that the thickness of the wetting layer increases with the increasing surface potential. The crossover, which is later for larger values of surface potential, appears in the evolution curve of the wetting layer. Before the crossover, the growth law is the surface potential dependant growth law. Subsequently, the growth law is the typical Lifshitz-Slyozov (LS) growth law. The results indicate that the surface potential can result in the mutual transformation between completely wetting and partially wetting for the substrate interface. It can be found that the higher surface potential leads to the faster and stronger transmission of the effect of the substrate on the spinodal decomposition in the bulk. 相似文献
6.
Tyana A. Rudolfsen Doug A. Watkinson Colin Charles Colin Kovachik Eva C. Enders 《Journal of Great Lakes research》2021,47(3):635-647
Understanding relationships between freshwater fishes and habitat is critical for effective fisheries and habitat management. Habitat suitability indices (HSI) are commonly used to describe fish–habitat associations in rivers and other freshwater ecosystems. When applied to large lakes however, standard sampling procedures are inadequate because of larger sampling areas and an increased risk of fish collection bias through one-time observations. Here, we use lake bathymetry, substrate, and multiple fish telemetry detections collected from a systematically deployed receiver grid to develop HSI for four fish species (lake sturgeon, freshwater drum, common carp, and walleye) in Lake Winnipeg. Seasonal variations in habitat use based on water depth and substrate were observed in three of four species. Lake sturgeon remained in shallow locations with predominantly gravel substrate near the mouth of the Winnipeg River regardless of season. Freshwater drum persisted over fine substrate in both summer and winter but had a broader depth range in the summer compared to winter. Common carp shifted from mid-range depths and silt substrate in the summer to shallow depths and gravel substrate in the winter. Walleye showed an unchanging association to fine substrate but expanded from primarily mid-range depths in the summer to include shallower depths in the winter. These findings show how multiple telemetry detections per fish can be combined with hydroacoustic data to provide informative habitat associations for fishes in a large lacustrine ecosystem. 相似文献
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介绍了适用于高容量、小型化硬盘用基板的各种微晶玻璃材料,简要讨论了各种微晶玻璃的化学组成、显微结构、主晶相种类以及各种微晶玻璃的特性,并对今后的发展趋势进行了展望。 相似文献
10.
介绍一种基于机器视觉的液晶玻璃基板质量在线检测系统。利用分布式视觉处理技术、采用模块化的图像处理系统设计,能够实现缺陷的精确提取与对缺陷的智能分类和分级,满足LCD液晶玻璃基板质量在线检测的需要。 相似文献