共查询到20条相似文献,搜索用时 156 毫秒
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红色荧光粉的在制备荧光转换型白光LED时是不可或缺的,因为红色荧光粉在制备高显色指数白光LED中发挥着重要的作用。LiEuW2O8是最近几年最新发展起来的一种很有潜力的红色荧光粉。主要研究了稀土离子掺杂对LiEuW2O8发光性能的影响。采用高温固相法制备钨酸锂铕系列红色荧光粉。La3+和Sm3+取代LiEuW2O8中的Eu3+,La3+和Sm3+通过再吸收的方式将能量传递给Eu3+,实现对Eu3+的敏化作用。La3+和Sm3+的掺杂并没有改变样品的激发和发射峰,也没有改变晶体结构,但是掺入后能显著提高样品的发射强度。La3+的最佳掺杂量(物质的量分数)为3%,Sm3+的最佳掺杂量为4%。 相似文献
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用热聚合法制备了掺Eu(DBM)3Phen螯合物的聚合物光纤,建立了团簇化铕离子相互作用模型,以此为基础研究该掺杂聚合物光纤的团簇现象。利用速率方程理论,结合光纤的抽运光透射率实验,得到所研究光纤中团簇化铕离子浓度。掺铕质量分数为0.1%,0.2%,0.3%,0.4%,0.5%,1%的聚合物光纤中团簇化铕离子的浓度分别为0.045,0.07,0.07,0.07,0.07,0.08。因此,该掺杂聚合物光纤的团簇化铕离子浓度较低且基本不随掺杂浓度的增加而增加,铕离子之间的团簇化现象不明显。 相似文献
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采用高温固相合成工艺制备了KSrPO4:x Eu3+红色发光材料,通过X射线衍射、荧光光谱、量子效率仪、封装对发光材料的晶体结构及发光特性进行了研究。XRD表明KSrPO4晶体结构并没有随着Eu3+的掺入而发生变化;荧光光谱表明KSrPO4:Eu3+在394 nm处存在最强激发峰,发射光谱最强发射峰为612nm;量子效率研究表明随着Eu3+掺杂量的增加,量子效率先增后降,在Eu3+掺杂量x=0.04时,量子效率存在最大值51%;封装光源的显色指数为83,色温3497 K,并且随着电流的变化色坐标(X,Y)基本保持不变,因此,KSrPO4:Eu3+红色发光材料作为近紫外激发的红色发光材料具有一定的潜力。 相似文献
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采用高温固相法成功合成了掺杂钼酸盐的ZnMoO4:Ce4+蓝色荧光材料。通过X 射线衍射(XRD)和荧光光谱等测试手段对所制备的材料的晶体结构和发光性能进行了表征。研究结果表明:实验按照理论化学计算比成功合成了ZnMoO4:Ce4+的蓝色荧光粉,该荧光粉为纯相的三斜结构;ZnMoO4:Ce4+在395 nm 处有强电子吸收,且在440 nm 处可发射高强度蓝光,其色坐标为(0.14,0.09);此外,当Ce 含量为3 mol%时,荧光粉发光强度最佳。 相似文献
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采用高温熔融法制备了Tm~(3+)/Dy~(3+)共掺杂铋酸盐玻璃样品。利用样品的差热分析曲线、拉曼光谱、红外透过光谱、吸收光谱、荧光光谱和荧光衰减曲线,对800nm激光二极管抽运下样品的1.47μm宽带发光特性进行了研究。研究结果表明,制备的铋酸盐玻璃具有良好的热稳定性、较低的声子能量和较高的红外透过率。当Dy~(3+)的摩尔分数为0.3%时,实现了对Tm~(3+)的1.47μm发光的敏化增强,其荧光谱线的半峰全宽为118nm。计算得到1.47μm发光的最大受激发射截面为4.37×10~(-21) cm~2,光纤放大品质因子为5.31×10~(-26) cm~3。 相似文献
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采用高温熔融淬火技术制备了1.0 mol% Tm3+离子和x mol% Er3+离子(x=0,0.5和1.5 mol%)掺杂 的系列碲酸盐玻璃,通过测量玻璃样品的差热扫描曲线(DSC)、X射线衍射(XRD)图和荧光光 谱,对不同 Er3+浓度下的玻璃物理性能和Tm3+离子荧光特性进行了研究。DSC结果显 示,研制的稀土掺杂碲酸盐玻璃 具有优异的热稳定性能,玻璃样品的析晶温度与转变温度之差大于130 ℃,而XRD图则证实了研制的玻璃 样品具有非晶结构特征。在808 nm泵浦激励下,随着Er3+离 子的引入,Tm3+离子3F4→3H6能级间跃迁产生 的1.85 μm波段荧光显著增强。当Er3+离子掺杂浓度为1.0 mol%时,荧光强度提高了约76%,荧光强度的 显著增强归因于Er3+离子和Tm3+离子之间的能量传递。然而,随着Er 3+离子掺杂浓度的继续增加,1.85 μm 波段荧光呈现出衰减现象,这归结于Er3+离子浓度的淬灭效应。研究表明,具有合 适浓度Er3+/Tm3+共掺碲 酸盐玻璃是一种应用于1.85 μm波段固体激光器和光纤放大器的理想 基质材料。 相似文献
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电子封装中的铝碳化硅及其应用 总被引:4,自引:1,他引:3
随着电子封装技术的迅速发展,铝碳化硅AlSiC金属基复合材料成为高新封装技术的热门话题之一。AlSiC在电子封装中优势凸现,文章主要介绍AlSiC的性能特点、类型、制备方法以及在电子封装中的应用,并展望了这类封装材料的发展趋势。 相似文献
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Weiguo Tian Jinming Zhang Jian Yu Jin Wu Jun Zhang Jiasong He Fosong Wang 《Advanced functional materials》2018,28(9)
An iridescent chameleon‐like material that can change its colors under different circumstances is always desired in color‐on‐demand applications. Herein, a strategy based on trichromacy and the dynamically tunable fluorescence resonance energy transfer (FRET) process to design and prepare these chameleon‐like fluorescent materials is proposed. A set of trichromic (red, green, and blue), solid fluorescent materials are synthesized by covalently attaching spiropyran, fluorescein, and pyrene onto cellulose chains independently. After simply mixing them together, a full range of color is realized. The chameleon‐like nature of these materials is based on the dynamic tunable FRET process between donors (green and blue) and acceptors (red) in which the energy transfer efficiency can be finely tuned by irradiation. Ultimately, the reversible and nonlinear regulation of fluorescence properties, including color and intensity, is achieved on a timescale recognizable by the naked eye. Benefited by the excellent processability inherited from the cellulose derivatives, the as‐prepared materials are feasibly transformed into different forms. Particularly, a fluorescent ink with the complicated fluorescent input–output dependence suggests more than a proof‐of‐concept; indeed, it suggests a unique method of information encryption, security printing, and dynamic anticounterfeiting. 相似文献
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黄铜是工业产品的重要基础性材料之一,其抗盐腐蚀性能的提升问题,近年来受到工业界和科研界的广泛关注。本文提出一种制备黄铜抗盐腐蚀涂层方法。首先,利用纳秒激光诱导出了具有微纳织构的黄铜超疏水表面,并用氟硅烷进行修饰增强其稳定性;然后在制备的超疏水性基体中注入硅油,获得超疏水光滑涂层表面;最后,浸入35wt% NaCl溶液中进行PDP和EIS测试,结果表明光滑表面的抗盐腐蚀性能优于普通超疏水表面,更优于原始黄铜表面。本研究可对金属防腐涂层发展起到一定的促进作用,对于激光诱导制备超疏水光滑表面具有重要意义,为工业领域的金属防腐蚀途径提供了方便和有效的手段。 相似文献
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Deliang Wang Junyi Gong Yu Xiong Hongzhuo Wu Zheng Zhao Dong Wang Ben Zhong Tang 《Advanced functional materials》2023,33(1):2208895
Organic ultralong room-temperature phosphorescence (RTP) materials have promising applications in anti-counterfeiting. To improve the encryption level, the exploration of organic materials with tunable solid-state long persistent luminescence is in urgent need. Herein, a series of organic ultralong RTP polymeric systems are prepared by doping versatile indolocarbazole isomers into the poly(vinyl alcohol) (PVA) matrix. Notably, the doping film 11,12-ICz@PVA exhibits excellent RTP property with an ultralong lifetime of 2.04 s and a high phosphorescence quantum yield of 44.1%. Theoretical calculations reveal that this excellent RTP property can be attributed to the strong electrostatic attraction resulting from the synergistic double hydrogen-bond between the isomer 11,12-ICz and PVA matrix. More impressively, color-tunable and time-dependent long persistent luminescence is successfully achieved through efficient phosphorescence energy transfer between the indolocarbazole isomers with ultralong blue RTP emissions and commercially available fluorescent dyes with emission colors ranging from green to red doped into the PVA matrix. Besides, diversified encryption patterns are fabricated to demonstrate the promising applications of these water-soluble doping PVA systems with tunable solid-state persistent luminescence in advanced anti-counterfeiting technology. 相似文献
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A simple method by employing white organic light-emitting diode (OLED) to simultaneously study the effects of magnetic fields (MFEs) on the fluorescent and phosphorescent emission was presented. The white OLED consisting of the blue fluorescent and red phosphorescent materials was fabricated. The low-pass filter chopped at 500 nm and the high-pass filter chopped at 550 nm were used to separate the MFEs on the blue fluorescence and red phosphorescence, separately. The magnetoelectroluminescences (MELs) on the fluorescence sharply increased at low magnetic field then tended to saturation at high magnetic field. While the MELs on the phosphorescence sharply increased at low magnetic field then slowly monotonically increased as the magnetic field further increased. Our results indicated that the magnetic-field modulated singlet-to-triplet electron–hole pair conversion combining with the magnetic-field modulated triplet–triplet annihilation process are the origins of the MFEs on the electroluminescence. 相似文献
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论述了集成光学光刻、镀膜工艺中对基片的清洗步骤,阐述了常规材料的腐蚀方法及腐蚀液配制,并分析了腐蚀工艺过程中易出现的问题. 相似文献