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331.
Phosphor-in-glass (PiG) typed robust color converters were fabricated using Pb-free silicate glasses for high-power white LED applications. SiO2-B2O3-RO(R=Ba,Zn) glass powder showed good sintering behavior and high visible transparency under the sintering condition of 750?°C for 30?min without noticeable interaction with phosphors. By simply changing the thickness of the PiG plate or mixing ratio of glass to Y3Al5O12:Ce3+ phosphor, CIE chromaticity coordinates of the LED can be easily controlled. Enhanced thermal quenching property of PiG compared to phosphor with conventional silicone resin suggests its prominent feasibility for high-power/high-brightness white LEDs. 相似文献
332.
Y.S. KimS.B. Heo H.M. LeeY.J. Lee I.S. KimM.S. Kang D.H. ChoiB.H. Lee M.G. KimDaeil Kim 《Applied Surface Science》2012,258(8):3903-3906
Transparent conductive GZO films were deposited on polycarbonate substrates by electron beam assisted radio frequency (RF) magnetron sputtering and then the influence of electron irradiation on the structural, optical and electrical properties of GZO films was investigated by using X-ray diffractometry, UV-vis spectrophotometry, four point probes, atomic force microscopy and UV photoelectron spectroscopy. Sputtering power was kept constant at 3 W/cm2 during deposition, while electron irradiation energy varied from 450 to 900 eV.Electron irradiated GZO films show larger grain sizes than those of films prepared without electron irradiation, and films irradiated at 900 eV show higher optical transmittance in the visible wavelength region and lower sheet resistance (120 Ω/□) than other films. The work-function is also increased with electron irradiation energy. The highest work-function of 4.4 eV was observed in films that were electron irradiated at 900 eV. 相似文献
333.
Heat-treatment was used to precipitate PbS quantum dots (QDs) in silicate glasses doped with different amounts of Ag2O, and the influence of Ag2O on QDs was investigated. Under given heat-treatment conditions, the absorption coefficients and photoluminescence intensities of PbS QDs increased with the addition of Ag2O. Ag clusters formed by thermal treatment nucleated formation of PbS QDs in glasses. 相似文献
334.
Mechanisms of the compositional dependence of blue emission from Nd3+/Tm3+ co-doped Ge–Ga–S–CsBr chalcohalide glasses were investigated. The blue upconversion emissions (centered at 475 nm) due to the Tm3+: 1G4 → 3H6 transition decreased as the CsBr/Ga ratio in glasses while the other upconversion emissions from the Nd3+ ions increased. Changes in the local environment of rare-earth ions incurred by the CsBr addition significantly increased the excited state absorption within Nd3+ ions. This resulted in the decrease in the Nd3+ → Tm3+ energy transfer rates that led to the large decrease in blue upconversion emission. 相似文献
335.
Xunsi Wang Baoan Song Wei Zhang Dai Shixun Guoxiang Wang Tiefeng Xu Xiang Shen Xianghua Zhang Chao Liu Kai Xu Jong Heo 《Journal of Non》2011,357(11-13):2403-2408
This work presents a detailed study on near-infrared and mid-infrared fluorescence emissions with five sets of Tm3+-doped 75GeS2–15Ga2S3–10CsI chalcohalide glass. They are prepared in normal or water drying process. Based on the diffusion-limited relaxation calculation, a detailed investigation is put forward to obtain efficient near-infrared or mid-infrared fluorescence emissions of Tm3+ on the effect of H2O on the Tm3+ fluorescence. Detailed investigations are given to the interacted energy transferring processes between rare-earth, impurities and vibrating phonons with the appearance of fluorescence quenching, along with Tm3+, H2O concentrations varying and energy gaps forming. The radioactive properties are analyzed using compensated diffusion-limited relaxation calculation method, and the near-IR and mid-IR fluorescence properties are evaluated in detail with experimental and theoretical analysis. 相似文献
336.
PbSe quantum dots (QDs) were synthesized in borosilicate glass and their optical properties were investigated. The typical quantum confinement effects were clearly observed from the absorption when the average radii of the QDs changed from 1.7 to 3.1 nm. Photoluminescence from PbSe QDs was achieved in 1.1–2.2 μm wavelength region that covers the entire fiber-optic telecommunication window. Borosilicate glasses containing controlled size of PbSe QDs provide potentials for the fiber-optic amplifiers. 相似文献
337.
Given a fixed p≠2, we prove a simple and effective characterization of all radial multipliers of FLp( mathbbRd ) mathcal{F}{L^p}left( {{mathbb{R}^d}} right) , provided that the dimension d is sufficiently large. The method also yields new L q space-time regularity results for solutions of the wave equation in high dimensions. 相似文献
338.
339.
We designed a carboxamide-based fluorescent chemosensor HTPQ ((E)-2-(((8-hydroxy-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)methylene)amino)thiophene-3-carboxamide) for detecting Al3+. HTPQ could probe Al3+ by fluorescence enhancement. Limit of detection for Al3+ toward HTPQ was 1.4 μM. Binding of HTPQ to Al3+ was determined to be a 1:1 ratio with the analysis of Job plot and ESI-mass. In addition, HTPQ was able to detect Al3+ using the test strip by fluorescent variation. The sensing process of Al3+ by HTPQ was presented by UV–vis titration, ESI–MS, Job plot, 1H NMR titration and DFT calculation.
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