Yb^3＋/Ho^3＋双掺氟氧硅酸盐微晶玻璃

用熔融技术制备了Yb3+/Ho3+双掺氟氧化物微晶玻璃,通过实验确定了掺稀土离子微晶玻璃的配比、熔化温度和退火温度.采用HitachiF-4500荧光分光光度计,激发波长为980nm激光器测定了样品的发射光谱.通过对光谱的分析,建立了上转换发光机制.测量了发光强度与抽运功率的关系.通过非线性拟合得出的斜率,确定了样品的540nm和650nm发射均为双光子过程.     

用SOI-Gel法制备Y_1Ba_2Cu_3O(7-δ)及超导电性

Y2O3、Ba2CO3；CuO作原料，将其制成相应的硝酸盐，利用柠檬酸强的蛰合作用，可以制得完、钡、铜稳定的配位化合物，形成溶胶，蒸发溶剂之后形成凝胶，加热到300℃时凝胶自燃，系统转变成Y2O3、Ba2CO3；CuO的超细粉体，经均匀混合后，压成413×1．5mm圆片，在930℃左右制成_1Ba_2Cu_3O(7-δ)超导体，经测试其零电阻转变温度为90．9K。     

Upconversion Luminescence Properties of Ho^3＋, Tm^3＋, Yb^3＋ Co-Doped Nanocrystal NaYF4 Synthesized by Hydrothermal Method

Nanocrystal of upconversion （UC） phosphor Ho^3＋, Tm^3＋ , and Yb^3＋ co-doped NaYF4 was prepared by the hydrothermal method in the presence of the complexing agent EDTA. Under 980 nm diode laser excitation, the impact of different concentrations of Ho^3＋ ion on the UC luminescence intensity was discussed. The law of luminescence intensity versus pump power shows that the 474 nm blue emission, 538 nm green emission, and 642 nm red emission are all due to the two-photon process, while the 450 nm blue emission is a three-photon process. The UC mechanism and processes were also analyzed. The sample was characterized by transmission electron microscopy （TEM） and X-ray diffraction （XRD）. The result shows that Ho^3＋ ,Tm^3＋ , and Yb^3＋ co-doped NaYF4 prepared by the hydrothermal method exhibits a hexagonal nanocrystal.     

Preparation of CaS∶Eu~(2 ), Sm~(3 ) by Solid Reaction Method and Its Photostimulated Luminescence

Thereisanurgentneedonopticalstoragemateri alswiththedevelopmentoflaserandopticalstoragetechnologyinrecentyears .Electrontrappingopticalstoragematerials (ETM )isanewtypeofopticalstor agematerials .Theybasicallyarewide band gapⅡ Ⅵsemi conductorcompoundsdopedwithtwotypesofselectedrareearthelementsthathavegroundstatesandexcitedstateswithinthewidebandgapoftheⅡ Ⅵsemiconductorcompoundhostmaterials .Lighten ergyisstoredinthiskindofmaterialbyexposingittoultravioletorvisiblelightandisreleasedthro…     

Preparation and luminescence properties of BaWO4：yb3＋/Tm3＋ nano-crystal

This research investigated the effect of different contents of Tm3+and different concentration ratios of Yb/Tm on the lumi-nescent properties of BaWO4:Yb3+/Tm3+nano-crystal synthesized by the hydrother...     

Investigation on Preparation and Fluorescence Properties of Oxy-Fluoride Glass Co-Doped with Er^3＋ and Yb^3＋

The glass sample based on the composition of 45PbF2-45GeO2-10WO3 co-doped with Yb^3 /Er^3 was prepared by the fusion method in two steps : melted at 950℃ for 20～25min then annealed at 380℃ for 4 h. Through the V-prism it is found that the refractive index of host glass and the sample are 1.517 and 1.65 respectively. The transmittance was observed by using the ultraviolet-visible-infrared spectrometer in the wavelength range from 0.35 to 2.5μm. The transmittance of the host glass is beyond 73%. That of the sample is beyond 50% and there are characteristic absorption peaks of rare-earth ions. The emission spectrum was measured by using the Hitachi F-4500 fluorescent spectrometer pumped by 980nm semiconductor laser. There are a strong emission peak at 530 nm and a weak peak at 650 nm.     

Preparation of CaS：Eu^2＋ , Sm^3＋ by Solid Reaction Method and Its Photostimulated Luminescence

The CaS:Eu^2 , Sm^3 powders were prepared by high-temperature solid method in a reducing atmosphere. The influences of temperature and fired-time on properties of samples were studied. XRD analysis shows that crystal structure of CaS has formed at 700℃. Spectrum analysis results show that the samples which were stimulated by 980 nm laser after excited by ultraviolet lamp emit red luminescence peaking at 649 nm.     

白光LED光色电参数特性的研究

白光发光二极管（WLED）光色电参数的特性,实验结果表明,随着正向驱动电流的增加,WLED相关色温（CCT）增大,发学效率降低恒流驱动时,LED的电压随着点亮时间的增加而降低（5分钟内）。通过分析,发现P-N结温、荧光粉浓度与其涂覆的厚度是影响这些光色参数变化的主要原因。     

稀土离子掺杂Ba0.65Zr0.35F2.70上转换纳米晶的制备与表征

采用水热法,以EDTA为络合剂制备了Ba0.65Zr0.35F2.70:Er3+,Yb3上转换纳米晶.采用XRD、TEM对样品进行物相、结构和形貌分析,确定了样品纳米晶的粒径尺寸,其粒径在20～ 40 nm之间.当Yb3:Er3+物质的量比为4:1时,上转换发光强度最强.根据泵浦功率与发光强度的关系曲线确定了523 nm、546 nm、650 nm的发射峰均属于双光子过程.