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冶金学院,沈阳 110004 ) 摘 要:在超声波作用下以均匀沉淀法制备Eu0.12Y1.88-xMxO3-δ (M=Mg,Ca)纳米晶荧光粉,用X射线衍射仪(XRD),透射电镜(TEM),荧光光谱对其进行表征,研究掺杂Mg2+,Ca2+对Y2O3:Eu3+纳米晶光致发光(PL)性能的影响.结果表明,掺杂Mg2+后,Y2O3?Eu3+的PL发射强度减弱,而掺杂Ca2+后Y2O3?Eu3+的PL发射强度得到明显增强,掺杂浓度高至15%(摩尔分数)后仍具有优良的发光性能,大大提高掺杂Y2O3?Eu3+纳米晶的猝灭浓度.样品Eu0.12Y1.78Ca0.10O3-δ具有最佳PL发射强度,是未掺杂Y2O3?Eu3+的2.4倍,且色纯度显著提高.掺杂样品PL性能的增强可归因于Eu3+的电荷迁移带(CTS)与接近Y(4d+5s)导带处缺陷态的叠加,与掺杂离子的电负性及掺杂离子后样品的晶......
一类有约束的分段线性系统双模预测控制曾锋1,高东杰1,李秀改21. 中国科学院自动化研究所2. 清华大学自动化系摘 要:研究分段线性(PL)系统预测控制问题,提出了PL系统双模预测控制,并证明了该方法的稳定性.该方法使用混合逻辑动态系统来建模PL系统,利用PL系统状态反馈控制来确定PL系统的受控不变集,并结合双模预测控制方法获得PL系统双模预测控制.该方法解决了系数矩阵的选择问题,不需要满足最终状态等式约束.一个分段线性系统的实例证明了该方法是可行的.关键词:分段线性系统;混合逻辑动态;状态反馈;受控不变集;双模预测控制;......
采用PLC可编程电控实现矿井通风机反风自动控制郭伟志淮北矿业集团摘 要:介绍了 PL C自动控制系统的主要程序,工作原理以及优点关键词:矿井通风;通风机反风;自动控制;......
Rim Blvd., Camas, Washington, 98607, USA) Abstract:Photoluminescence (PL) characteristics of Tb-doped silicon rich oxide (SRO) films prepared by DC-sputtering and post-annealing processes were studied. The silicon richness of the SRO film could be controlled by varying the sputtering power and oxygen concentration in the sputtering chamber. PL emission from the as-deposited sample was found......
退火温度对草酸/硫酸混合液中制备的AAO薄膜光致发光的影响李守义,南雅公,韩久宁河西学院物理与机电工程学院摘 要:采用电化学阳极氧化法,在不同浓度比的草酸/硫酸混合电解液中制备了系列AAO薄膜样品,考察了用250nm波长激发时,从0℃到600℃温度范围内AAO薄膜退火后的光致发光(PL)特性.结果表明,AAO薄膜在300-500nm范围内有一个较强的PL带,在0℃时随硫酸浓度的增加,AAO薄膜的PL强度逐渐增强,发光峰位逐渐蓝移;退火温度对AAO薄膜的PL强度和峰位有很大的影响.实验表明AAO薄膜的PL与薄膜内不同存在或分布形式的草酸杂质形成的250和296nm发光中心密切相关.关键词:多孔阳极氧化铝;光致发光;蓝移;退火;......
photoelectron spectroscopy (XPS) and photoluminescence (PL). The effects of Y and Cd ions on the optical properties of the samples were studied. Doping of Y into ZnO evidently increases the intensity of UV... an intense violet emission in the room temperature PL spectrum, which could be a potential candidate material for optoelectronic applications. Key words: ZnO nanopowders; chemical precipitation; optical......
微乳液法制备ZnS∶Cu纳米微粒及其光学性能的表征 李磊1,张韵慧1 (1.天津大学材料学院,天津 300072) 摘要:利用微乳液法制备出ZnS∶Cu纳米微粒.XRD表明微粒粒径为3~5nm,且为立方晶型结构.在紫外吸收光谱中,ZnS∶Cu纳米微粒吸收峰蓝移.发射光谱表明ZnS∶Cu纳米微粒产生一个位于482nm的绿色发射带. 关键词:ZnS∶Cu; 微乳液; 纳米微粒; [全文内容正在添加中] ......
by solid-state reaction at high temperature, and their photoluminescence (PL) properties were investigated. (Gd1-xEux)Ba3B9O18 formed solid solutions in the range x=0-1.0. The optical band gaps calculated... phosphors showed well-known Eu3+ excitation and emission. The energy transfer from Gd3+ to Eu3+ was verified with PL spectra. The dependence of PL intensity on Eu3+ concentration was also studied......
and Applications,Peking University,Beijing 100871,China) Abstract:The photoluminescent(PL)and electroluminescent(EL)properties of a series of ligand emitting rare earth complexes(including Y3+,La3+,Gd3+ and Lu3...′-dipyridine(Bipy)and phenanthroline(Phen).Measured with 60 nm thin film of these complexes vaporized in vacuum on quartz substrates,a good regularity in the PL properties was observed.For rational comparison......
纳米硅量子线的发光特性研究 俞大鹏1 (1.北京大学物理系介观物理国家重点实验室;2.北京大学电子显微镜实验室,北京,100871) 摘要:利用脉冲激光蒸发或高温物理升华的方法,制备出纯度极高,直径分布均匀(13nm左右)的硅的一维量子线.光致发光(PL)测量显示,在313.5nm激光激发下,室温下硅量子线具有红绿蓝三色发光.对硅量子线进行氧化处理后,随氧化时间的增加,红光PL峰发生蓝移,而绿,蓝峰没有移动.红光PL与量子尺寸限制效应有关,而绿,蓝光PL来源于表层氧化硅中的缺陷发光. 关键词:纳米硅; 量子线; 光致发光; 量子限制; 高分辨电镜; [全文内容正在添加中] ......
