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排序方式: 共有678条查询结果,搜索用时 15 毫秒
61.
Arslan Usman M.S. Rafique M. Khaleeq-ur-Rahman K. Siraj Safia Anjum H. Latif Taj M. Khan Mazhar Mehmood 《Materials Chemistry and Physics》2011
The structure and surface morphology of Ni-incorporated diamond like carbon (Ni:DLC) films have been investigated. These films were deposited on Si substrates using pulsed laser deposition (PLD) technique. A KrF Excimer laser (λ = 248 nm) was used for co-ablation from multi component Ni–graphite target. The concentration of Ni was varied by ablating the Ni part of the target with various numbers of laser pulses. The SEM and AFM analysis reveals that the surface is composed of segregates of Ni which increases with the increase in Ni content during the growth process. The structural investigations by XRD and Raman spectroscopy provided information about the orientation of the incorporated constituent and the ordering of the carbon species. Maximum height of the nano structures which were observed on the surface was ∼50 nm. The G-peak of the graphite was shifted towards higher wave number due to enhancement in SP2 sites which have been increased due to the increase in the Ni concentration. A small change in the surface roughness ranging from 7.78 nm to 13.1 nm due to increased Ni concentration was also observed. 相似文献
62.
A mold was designed to create various strains in polyethylene terephthalate (PET) substrates before the deposition of TiO2 film to simulate deposition process on a cylindrical drum. The residual stress of the PET substrate with TiO2 film significantly increased with increasing strain, decreasing the radius of curvature. Compared to the as-received PET substrate, there was a noticeable increase in the surface roughness in the PET/TiO2 specimens when a large strain was applied. The formation of voids or cavities in the TiO2 layer significantly increased the roughness of the specimen. The mean cavity size and depth increased with increasing strain. For strains ≦ 4%, the specimen's hardness and Young's modulus factored by the voids/cavities increased with increasing surface roughness. The optical absorption increased with increasing surface roughness before becoming asymptotic to a constant value. The strain applied to the PET substrate before TiO2 deposition greatly affects the optical reflection, transmittance, and absorption. 相似文献
63.
论述了在硅基板上用热灯丝法制备金刚石红外增透保护膜的工艺,通过多灯丝法、预打磨处理以及加偏压等方法得到了特性优良的金刚石薄膜,并利用对金刚石薄膜─硅板体系红外透射率的曲线拟合,推知了一系列不易直接测量的特性参数,如折射率,吸收系数,薄膜厚度等。 相似文献
64.
一种新型聚烯烃消光膜的开发研究 总被引:1,自引:0,他引:1
采用共混制备新型聚烯烃消光膜,考察了聚乙烯(PE)与聚丙烯(PP)树脂的熔体质量流动速率(MFR)及主链结构对薄膜消光性能的影响,发现采用共混能够极大地改善薄膜消光性能,并选定具有合适MFR和主链结构的PE与PP树脂及确定两者配混比例,实现了消光性能优良的新型聚烯烃消光膜的制备。 相似文献
65.
Jung-Sik KimRobert A. Rudkin Xin WangAlan Atkinson 《Journal of the European Ceramic Society》2011,31(13):2231-2239
3YSZ green layers approximately 10 μm thick were screen-printed onto 3YSZ substrates and their constrained sintering kinetics were measured at 1100-1350 °C using an optical dilatometer. The densification rates of the same powder in the form of pellets and free-standing films were also measured. The constrained densification rate was greatly retarded compared with the free densification rate at a given temperature and density. The retardation increased with increasing density and temperature and could not be properly accounted for by existing theories of constrained sintering. As a result the apparent activation energy is much lower for constrained sintering (135 ± 20 kJ mol−1) than for free sintering (660 ± 30 kJ mol−1). It is proposed that this is because the constrained microstructure exhibits larger and more widely separated pores at the higher temperatures. 相似文献
66.
Surface characterization of titanium oxide films synthesized by ion beam enhanced deposition 总被引:1,自引:0,他引:1
Feng Zhang S. Jin Yingjun Mao Zhihong Zheng Yu Chen Xianghuai Liu 《Thin solid films》1997,310(1-2):29-33
In this article, titanium oxide films were prepared by ion beam enhanced deposition where titanium was evaporated by electron beam and simultaneously bombarded with xenon ion beams at an energy of 40 keV in an O2 environment. X-ray photoelectron spectroscopy and Auger electron spectroscopy were used to research the chemical state and composition of the titanium oxide films. The results show that surface of the film was fully oxidized. After the surface was removed by argon ion sputtering, the results show that Ti2+, Ti3+ and Ti4+ states exist on the sputtered surface. The atomic concentration of all the three titanium states were calculated. The chemical shift of O 1s peak was also observed on the near surface. 相似文献
67.
采用溶胶-凝胶方法在普通的载玻片上制备了CdS微晶掺杂的TiO2-SiO2复合薄膜。用正硅酸乙酯、钛酸丁酯、醋酸镉作原料,比较了硫脲和硫化乙氨的硫化作用。不同热处理温度、时间的吸收光谱表明,薄膜中存在着量子尺寸效应。采用Z-Scan技术测量了薄膜的非线性吸收及非线性折射率。 相似文献
68.
非晶硅(a-Si)薄膜太阳能电池是取之不尽的洁净能源-太阳能的光电元(组)件。文章详述了a-Si薄膜太阳能电池的工艺优势,市场开发状况,可能应用领域,存在问题和展望。 相似文献
69.
70.
英美电影文学、音乐MTV与外语视听教学 总被引:4,自引:0,他引:4
杜曾慧 《南京工业职业技术学院学报》2002,2(4):29-31
本分析了英美电影学和音乐、MTV在多媒体教学模式下的优势和特点。它们在外语视听课上的运用,丰富了教学内容,提高了整体教学质量。 相似文献