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91.
92.
The purpose of this work was to determine the influence of ion implantation on the oxidation resistance of ZrN coatings. Samples were prepared on AISI 304 stainless steel by cathodic arc deposition. They were submitted to Y implantation at 150 °C with various fluences using a metal vacuum vapour arc ion implanter. The oxidation behaviour of as-deposited and Y-implanted ZrN coatings was characterized by weight gain measurement. The oxidation resistance of the ZrN coating was reduced after it was implanted with yttrium at a low fluence but improved at higher fluence. X-ray photoemission spectroscopy and glancing angle X-ray diffraction were employed to analyze the valence states of the oxide scale and the phase composition of the oxidation layers. Yttrium implantation can greatly improve the oxidation resistance of the ZrN coating. 相似文献
93.
For formation of β-FeSi2 using ion beam sputter deposition (IBSD) method, sputter etching (SE) followed by thermal annealing is effective substrate treatment to obtain highly (100)-oriented β-FeSi2 on Si(100). However, the best condition of these treatments are not yet known. In this work, the effect of SE together with annealing process on the orientation of the film is investigated. Prior to the deposition of Fe, the substrate is irradiated by Ne+ ions with various energy and fluence followed by thermal annealing at 1073 K for 60 min. The overall results show the most suitable SE condition using Ne+ ion on IBSD method is the energy of 1 keV with the fluence of 3.0×1019 ions /m2. 相似文献
94.
U. Kamachi Mudali H. S. Khatak Baldev Raj M. Uhlemann 《Materials and Manufacturing Processes》2004,19(1):61-73
It is well known that the addition of nitrogen to steels and stainless steels enhances the passivity and localized corrosion resistance, in addition to improving the mechanical properties. Selective alloying of surfaces of steels and stainless steels with nitrogen could also enhance the corrosion resistance and improve the mechanical properties without affecting the bulk properties. Techniques like ion implantation, laser alloying, nitriding, etc. can be effectively used to introduce very high levels of nitrogen. In addition, these techniques can also produce modified surfaces with novel microstructures to further improve the properties. The surface alloying methods also provide an opportunity to selectively nitrogenate the surface of finished components in order to obtain better properties. The review highlights the techniques, modifications and the properties obtained further. 相似文献
95.
本文论述了自动火灾离子感烟探测器的结构组成及其电路工作原理。通过对探测器电路的具体分析,进一步阐明自动火灾离子感烟探测器的相关功能。 相似文献
96.
本文基于对电子束蒸发的a-Si1-xGdx薄膜的光吸收,变温电导特性和ESR实验研究的结果,对Gd^3+离子的作用进行了分析研究。Gd原子的外壳层5d^16s^2产生轨道杂化,在a-Si网格中形成五配位的Gd^3+离子。Gd^3+离子的杂化轨道除与网格中的Si原子键合外,还能与Si的悬挂键Si3^0键合,起补偿悬挂键的作用。Gd^3+离子的角动量J的多重态间的跃迂吸收,改变了薄膜的近红外吸收特性。 相似文献
97.
A.M. Borisov E.S. Mashkova A.S. Nemov E.S. Parilis 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):443-448
The temperature dependence of ion-induced electron emission yield γ under 30 keV Ar+ ion impacts at incidence angles θ = 0−80° under dynamically steady-state conditions has been measured for polygranular graphite POCO-AXF-5Q. The fluencies were 1018–1019 ion/cm2, the temperatures varied from the room temperature (RT) to 400 °C. The RHEED has shown that same diffraction patterns correspond to a high degree of disorder at RT. At high temperature (HT), some patterns have been found similar to those for the initial graphite surfaces. The dependence γ(T) has been found to be non-monotonic and for normal and near normal ion incidence manifests a step-like increase typical for a radiation induced phase transition. At oblique and grazing incidence (θ > 30°), a broad peak was found at Tp = 100 °C. An analysis based on the theory of kinetic ion-induced electron emission connects the behavior of γ(θ,T) to the dependence of both secondary electron path length λ and primary ion ionizing path length Re on lattice structure that drastically changes due to damage annealing. 相似文献
98.
离子交换型Cu/SiO2催化剂的制备和表征 总被引:1,自引:0,他引:1
李工 《石油化工高等学校学报》1995,8(3):14-17
用离子交换法制备了Cu/SiO2催化剂,并在催化活性与稳定性方面与浸渍型的Cu/SiO2催化剂进行了对比,采用差热分析(DTA)、X射线衍射(XRD)、比表面测定等方法对催化剂进行了表征 相似文献
99.
岩心聚焦离子束扫描电镜(FIB-SEM)图像存在灰度分布不均及孔隙内局部高亮等现象,采用传统图像分割算法所得孔隙分割精度较低,而基于轮廓的分割算法需对孔隙进行人工标记,操作繁琐且无法精确提取孔隙。提出一种利用卷积神经网络的端到端岩心FIB-SEM图像分割算法。结合光流法与分水岭分割图像标注法构建岩心FIB-SEM数据集,联合ResNet50残差网络、通道和空间注意力机制提取特征信息,采用改进的特征金字塔注意力模块提取多尺度特征,利用亚像素卷积模块经上采样获取更精细的孔隙边缘并恢复为原始分辨率。实验结果表明,与阈值分割算法和基于主动轮廓的岩心FIB-SEM分割算法相比,该算法分割精度更高且无需人工操作,其平均像素精度和平均交并比分别达到90.00%和85.81%。 相似文献
100.