Photoluminescent properties of tunable green-emitting oxynitride (Ba3-xSrx)Si6O12N2:Eu2+phosphor and its application in white LEDs

Green emitting Eu2+-doped (Ba3?xSrx)Si6O12N2 solid solutions were synthesized through solid state reaction at 1350 oC for 10 h under a N2/H2 atmosphere. The XRD patterns revealed that the solid solutio...     

High temperature stability of Eu2＋-activated nitride red phosphors

The novel nitride-based luminescent materials have received much attention since the end of the last century. In this paper, the commercial Eu2＋-activated nitride red phosphors, Sr1.95Si5N8：Eu0.05, Sr1.85Si5N8：Eu0.15 and Ca0.99AlSiN3：Eu0.01 phosphors were an-nealed at different temperatures （beyond 300 oC） to investigate the dependence of their luminescence performance and structure vari-ability on the temperature. By photoluminescence spectra, X-ray diffraction （XRD） and thermogravimetry-differential scanning calo-rimetry （TG-DSC） analysis, the high temperature stability of the hosts and activator of the three samples were disclosed. With the an-nealing temperature increasing, the activator Eu2＋ions were firstly oxidized and then host in Sr1.95Si5N8：Eu0.05 and Sr1.85Si5N8：Eu0.15, but for Ca0.99AlSiN3：Eu0.01, only the oxidation of the host could be observed, which would lead to the luminescence degradation and even failure of these phosphors. The activator Eu2＋ions were much more stable in CaAlSiN3：Eu than Sr2Si5N8：Eu due to their crystal surroundings, and its concentration also influenced the temperature stability of Sr2Si5N8：Eu.     

白光LED用硅酸盐系列荧光粉的专利分析

白光LED用硅酸盐荧光粉主要应用在对显色指数不高的暖白光照明领域与中低端液晶背光显示领域,其专利申请量表示了荧光粉的技术发展趋势。以含有M、Si、O、Ce/Eu的白光LED用硅酸盐荧光粉为主要研究对象,对专利文献著录项目数据与核心技术内容进行统计分析,讨论了其全球专利的申请趋势、产出国家或地域分布情况、申请目标国家或地域比例情况,全球主要研究单位专利申请情况,以及其专利在华主要申请单位技术分布情况、在华主要申请单位申请量排名情况等,希望对白光LED用荧光粉的企业及行业发展提供参考与借鉴。     

十二种小麦样品五种微量元素的分析

通过采用电感藕合等离子发射光谱对１２种小麦品种进行了钙、镁、铁、锌、铝等５种微量元素的含量分析。结果表明：小麦样品中微量元素含量最高的是钙、镁，其次是铁、锌和铝，其中对人体有益的元素远远不能满足人体的需要。     

Effect of MgF2-H3BO3 flux on the properties of (Ce,Tb)MgAl11O19 phosphor

The green-emitting(Ce,Tb)MgAl11O19(CTMA) phosphor was prepared by the conventional high temperature solid-state reaction method.The effect of fluxes on the crystal structure,particle morphology,size distribution and photoluminescence properties of CTMA phosphor was investigated by means of the X-ray powder diffraction,scanning electron microscopy and photoluminescence spectrum.The results showed that the addition of appropriate amount of MgF2-H3BO3 flux improved the phase purity of CTMA phosphor,and influen...     

浅谈锚网梁联合支护在软岩巷道中的应用

介绍了安源煤矿锚网梁联合支护的技术经验和效果分析 ,同时也为支护质量提出了新的管理手段     

Sr_(1-x)Al_(1+y)Si_(4-y)N_(7-y)O_y:xEu~(2+)橙色荧光粉的合成及发光特性研究

采用常压高温固相法合成一种新型的氮氧化物橙色荧光粉SrAl1+ySi4-yN7-yOy:Eu2+。结合X射线衍射(XRD)、扫描电镜(SEM)和荧光光谱等分析手段,研究了荧光粉的组分配比变化对其物相结构的影响,结果发现当0≤y≤0.225时,该物质属于SrAlSi4N7结构。结合对离子半径及晶格常数变化等的分析,推断晶格中氧是以Al-O键取代了晶格中的Si-N键的方式而存在。通过对该荧光粉的光色特性研究发现,SrAl1+ySi4-yN7-yOy:Eu2+荧光粉可被近紫外到可见光有效激发,产生580~600 nm的橙光发射。对比Sr0.9Al1.225Si3.775N6.775O0.225:Eu0.1荧光粉和Sr0.9AlSi4N7:Eu0.1荧光粉的斯托克斯位移发现,Al-O的引入使得Sr0.9Al1.225Si3.775N6.775O0.225:Eu0.1荧光粉的非辐射弛豫几率相对较小,从而具有相对更高的热稳定性。因此,SrAl1+ySi4-yN7-yOy:Eu系列荧光粉是一款颇具前景的白光LED用橙色荧光粉。     

贵州茅台和五粮液投资价值比较分析

一、贵州茅台和五粮液基本情况简介: 贵州茅台酒股份有限公司于2001年7月30日发行7150万人民币普通股,其中国有股存量发行650万股,每股发行价31.39元,发行后总股本25000万股,全面摊薄市盈率23.93倍,预计今年全面每股净利润能达     

白光LED用荧光粉的国内外专利分析

发光二极管(Light Emitting Diode,LED)因具有高效节能、绿色环保、超长寿命等优势,被视为最具发展前景的新一代照明技术。此外,因具有功耗低、色彩还原性好、响应快、寿命长等优势,白光LED在液晶显示(Liquid Crystal Display,LCD)用背光源领域的市场份额也在迅速增长。自1962年NickHolony等利用磷砷化镓(GaAsP)制备出第一支红光LED以来,经过50年的发展,LED的发光范围逐渐扩展到绿光、黄光,光效也从早期的0.1lm/W达到的254m/W(2012年4月)。由于白光最     

白光LED荧光粉研究及应用新进展

基于白光发光二极管技术的迅速发展以及荧光粉对白光LED器件的发光效率、显色性和使用寿命等性能的决定性影响,系统阐述了蓝光LED芯片激发用铝酸盐、硅酸盐、氮化物和氮氧化物系列黄色、红色和绿色荧光粉的研究进展和应用现状。探讨了上述荧光粉的研究重点、发展趋势和应用前景,指出需要进一步提高铝酸盐黄粉的发光效率,开发新型高光效氮化物和氮氧化物红粉和绿粉及其低成本制备技术,以满足高光效、高显色、低光衰型白光LED器件制作需要。