采用脉冲激光烧蚀法,以多晶3C-SiC陶瓷片为靶材,制备了悬浮于去离子水中的非晶SiC纳米颗粒。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)、傅里叶变换红外吸收光谱(FTIR)、紫外可见吸收光谱(UV-Vis)和光致发光谱(PL)等测试...采用脉冲激光烧蚀法,以多晶3C-SiC陶瓷片为靶材,制备了悬浮于去离子水中的非晶SiC纳米颗粒。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)、傅里叶变换红外吸收光谱(FTIR)、紫外可见吸收光谱(UV-Vis)和光致发光谱(PL)等测试手段对其形貌、结构和光学性质进行了分析。结果表明:这些纳米颗粒由大量的非晶SiC构成,粒径在8~9 nm,光学带隙为3.28 e V;样品表现出较强的光致发光,发光峰位于415 nm处,这主要是由于量子限制效应造成的。展开更多
TN249 2004010265 激光用于LCD板ITO膜修复的研究=Study of applicationof laser to repairing ITO film on LCD board[刊,中]/宁继平(天津大学精密仪器与光电子工程学院.天津(300072)),李嘉强…∥光电工程.—2003,30(2).—15-17,20 对...TN249 2004010265 激光用于LCD板ITO膜修复的研究=Study of applicationof laser to repairing ITO film on LCD board[刊,中]/宁继平(天津大学精密仪器与光电子工程学院.天津(300072)),李嘉强…∥光电工程.—2003,30(2).—15-17,20 对激光修复LCD板ITO膜的过程及影响因素进行了理论分析和计算。设计并加工出一套激光聚焦系统。展开更多
To improve the ablation resistance of carbon/carbon(C/C)composites,a SiC/ZrC-ZrB2 double layer coating was fabricated by pack cementation and slurry-sintering method.The ablation resistance of the SiC/ZrC-ZrB2 coating...To improve the ablation resistance of carbon/carbon(C/C)composites,a SiC/ZrC-ZrB2 double layer coating was fabricated by pack cementation and slurry-sintering method.The ablation resistance of the SiC/ZrC-ZrB2 coating was tested under plasma flame above 2300°C.The results indicate that the SiC/ZrC-ZrB2 double layer coating exhibits superior ablation resistance than the ZrC-ZrB2 single layer coating.After being ablated under the plasma flame for 20 s,the mass and linear ablation rates of the ZrC-ZrB2 coating are 0.89 mg/s and 15.3μm/s,while those for SiC/ZrC-ZrB2 coating are 0.09 mg/s and 24.15μm/s,respectively.During ablation,the SiC inner layer can generate SiO2 glass and result in the formation of ZrO2-SiO2 molten film.Compared with the ZrO2 molten film formed on the ZrC-ZrB2 coating surface,the ZrO2-SiO2 molten film with lower oxygen diffusion rate and viscosity enables the SiC/ZrC-ZrB2 coating to have better self-healing ability.Therefore,the enhanced ablation resistance of the SiC/ZrC-ZrB2 coating can be attributed to the formation of dense ZrO2-SiO2 molten film under the plasma flame.展开更多
文摘采用脉冲激光烧蚀法,以多晶3C-SiC陶瓷片为靶材,制备了悬浮于去离子水中的非晶SiC纳米颗粒。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)、傅里叶变换红外吸收光谱(FTIR)、紫外可见吸收光谱(UV-Vis)和光致发光谱(PL)等测试手段对其形貌、结构和光学性质进行了分析。结果表明:这些纳米颗粒由大量的非晶SiC构成,粒径在8~9 nm,光学带隙为3.28 e V;样品表现出较强的光致发光,发光峰位于415 nm处,这主要是由于量子限制效应造成的。
基金Supported by Hunan Province Nature Science Foundation of China(No.03JJY3015)and Foundation for University Key Teacher by the Ministry of Education(2000-06)
文摘TN249 2004010265 激光用于LCD板ITO膜修复的研究=Study of applicationof laser to repairing ITO film on LCD board[刊,中]/宁继平(天津大学精密仪器与光电子工程学院.天津(300072)),李嘉强…∥光电工程.—2003,30(2).—15-17,20 对激光修复LCD板ITO膜的过程及影响因素进行了理论分析和计算。设计并加工出一套激光聚焦系统。
基金Project(51304249)supported by the National Natural Science Foundation of ChinaProject(14JJ3023)supported by the Science Foundation of Hunan Province,China。
文摘To improve the ablation resistance of carbon/carbon(C/C)composites,a SiC/ZrC-ZrB2 double layer coating was fabricated by pack cementation and slurry-sintering method.The ablation resistance of the SiC/ZrC-ZrB2 coating was tested under plasma flame above 2300°C.The results indicate that the SiC/ZrC-ZrB2 double layer coating exhibits superior ablation resistance than the ZrC-ZrB2 single layer coating.After being ablated under the plasma flame for 20 s,the mass and linear ablation rates of the ZrC-ZrB2 coating are 0.89 mg/s and 15.3μm/s,while those for SiC/ZrC-ZrB2 coating are 0.09 mg/s and 24.15μm/s,respectively.During ablation,the SiC inner layer can generate SiO2 glass and result in the formation of ZrO2-SiO2 molten film.Compared with the ZrO2 molten film formed on the ZrC-ZrB2 coating surface,the ZrO2-SiO2 molten film with lower oxygen diffusion rate and viscosity enables the SiC/ZrC-ZrB2 coating to have better self-healing ability.Therefore,the enhanced ablation resistance of the SiC/ZrC-ZrB2 coating can be attributed to the formation of dense ZrO2-SiO2 molten film under the plasma flame.
