The aim of this presentation is to report a new result of afterglow materials. The Y 2O 2S∶Ln 3+ (Ln=Sm, Tm) phosphors show bright reddish orange and orange-yellow colors when excited by UV or visible light. The m...The aim of this presentation is to report a new result of afterglow materials. The Y 2O 2S∶Ln 3+ (Ln=Sm, Tm) phosphors show bright reddish orange and orange-yellow colors when excited by UV or visible light. The main spectroscopic characterizations of Sm 3+ and Tm 3+ in yttrium oxysulfide and their long-lasting phosphorescence were measured and discussed in this presentation. Their long-lasting phosphorescence can be seen by the naked eyes clearly for about one hour in the dark room after the irradiation light sources were removed. XRD and photoluminescence (PL) spectra as well as the luminance decay were used to characterize these long-lasting phosphorescence phosphors. The results of XRD indicate that the products synthesized through the flux fusion method under 1050 ℃ for 6 h have a good crystallization without any detectable amount of impurity phase. Both the PL spectra and luminance decay results reveal that these phosphors have efficient luminescent and good long-lasting properties. We believe that the experimental data gathered in our present work will be useful in finding some new long-lasting phosphors with different colors.展开更多
Hydrolytic equilibria of Tm (III) in KOH solutions were studied at 25°C. A spectrophotometry with m-cresol purple and 2-naphthol as pH indicators was used at an ionic strength of not more than 0.0005. The results...Hydrolytic equilibria of Tm (III) in KOH solutions were studied at 25°C. A spectrophotometry with m-cresol purple and 2-naphthol as pH indicators was used at an ionic strength of not more than 0.0005. The results indicate that in freshly prepared solutions at pH ranging between 6 and 10 Tm is present as , , and . The stepwise stability constants of hydroxide complexes calculated at zero ionic strength were obtained as coefficient of linear regression equations from the graph of optical densities of the indicators in Tm solutions at varying pH.展开更多
YbSO4 purification by an electrolytic reduction method from Tm-Yb-Lu concentrates in sulphate medium was studied, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode respectively under normal atmos...YbSO4 purification by an electrolytic reduction method from Tm-Yb-Lu concentrates in sulphate medium was studied, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode respectively under normal atmosphere without nitrogen or argon gas protection. The parameters of the electrodes, such as their areas, positions, and the distance between the anode and cathode were optimized for the electrolytic reduction process. By the optimal process, the product YbSO4 is purified to 99. 5% with recovery of 80%. Meanwhile, Lu is also concentrated into 50%, which is beneficial to its further purification.展开更多
A high power cryogenic cooling Tin-doped （2%） GdVO4 laser double-end-pumped by fiber-coupled-diode： with the center wavelength of 804.5 nm at 21 ℃ is reported. The highest continuous-wave （CW） power of 2.35 W at...A high power cryogenic cooling Tin-doped （2%） GdVO4 laser double-end-pumped by fiber-coupled-diode： with the center wavelength of 804.5 nm at 21 ℃ is reported. The highest continuous-wave （CW） power of 2.35 W at 1903 nm is attained at pump power of 24 W. The slope efficiency is 12.5% and the tt, reshoht is 3.2 W. Single- and double-end-pumped types are investigated.展开更多
A series of fluorotellurite glasses based on（81–x）Te O2-（10＋x）KF-9La2O3（TKL）, where x=0 mol.%, 5 mol.%, 10 mol.%, 15 mol.%, doped with 2000 ppm Tm2O3, were prepared by the conventional melt quenching method.Th...A series of fluorotellurite glasses based on（81–x）Te O2-（10＋x）KF-9La2O3（TKL）, where x=0 mol.%, 5 mol.%, 10 mol.%, 15 mol.%, doped with 2000 ppm Tm2O3, were prepared by the conventional melt quenching method.The influence of KF content on the thermal stability and optical spectroscopic properties of the Tm3＋ doped fluorotellurite glasses were investigated by differential scanning calorimetry（DSC）, X-ray diffraction（XRD）, density measurement, Fourier transform infrared spectroscopy（FTIR）, UV-VIS-NIR optical spectroscopy and fluorescence spectroscopy.Judd-Ofelt intensity parameters of Tm3＋ in as-prepared glasses were determined and used to calculate the spontaneous emission probabilities and the radiative lifetime for the 4f-4f transitions of the Tm3＋ ions.Stimulated emission cross sections in the 1470 nm region（σse） were evaluated by Füchtbauer-Ladenburg formula.The results showed that KF substitution of Te O2 was beneficial to improving the thermal stability, decreasing glass density and reducing the content of OH related groups for the investigated fluorotellurite glasses.The glass with composition of 66 Te O2-25KF-9La2O3（named TKL25） had the longest radiative lifetime of the 3H4（361 μs） and the largest FWHM×σse value（420.07×10–28 cm3）, which made it a promising material for S-band fiber amplifiers.展开更多
文摘The aim of this presentation is to report a new result of afterglow materials. The Y 2O 2S∶Ln 3+ (Ln=Sm, Tm) phosphors show bright reddish orange and orange-yellow colors when excited by UV or visible light. The main spectroscopic characterizations of Sm 3+ and Tm 3+ in yttrium oxysulfide and their long-lasting phosphorescence were measured and discussed in this presentation. Their long-lasting phosphorescence can be seen by the naked eyes clearly for about one hour in the dark room after the irradiation light sources were removed. XRD and photoluminescence (PL) spectra as well as the luminance decay were used to characterize these long-lasting phosphorescence phosphors. The results of XRD indicate that the products synthesized through the flux fusion method under 1050 ℃ for 6 h have a good crystallization without any detectable amount of impurity phase. Both the PL spectra and luminance decay results reveal that these phosphors have efficient luminescent and good long-lasting properties. We believe that the experimental data gathered in our present work will be useful in finding some new long-lasting phosphors with different colors.
文摘Hydrolytic equilibria of Tm (III) in KOH solutions were studied at 25°C. A spectrophotometry with m-cresol purple and 2-naphthol as pH indicators was used at an ionic strength of not more than 0.0005. The results indicate that in freshly prepared solutions at pH ranging between 6 and 10 Tm is present as , , and . The stepwise stability constants of hydroxide complexes calculated at zero ionic strength were obtained as coefficient of linear regression equations from the graph of optical densities of the indicators in Tm solutions at varying pH.
文摘YbSO4 purification by an electrolytic reduction method from Tm-Yb-Lu concentrates in sulphate medium was studied, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode respectively under normal atmosphere without nitrogen or argon gas protection. The parameters of the electrodes, such as their areas, positions, and the distance between the anode and cathode were optimized for the electrolytic reduction process. By the optimal process, the product YbSO4 is purified to 99. 5% with recovery of 80%. Meanwhile, Lu is also concentrated into 50%, which is beneficial to its further purification.
文摘A high power cryogenic cooling Tin-doped （2%） GdVO4 laser double-end-pumped by fiber-coupled-diode： with the center wavelength of 804.5 nm at 21 ℃ is reported. The highest continuous-wave （CW） power of 2.35 W at 1903 nm is attained at pump power of 24 W. The slope efficiency is 12.5% and the tt, reshoht is 3.2 W. Single- and double-end-pumped types are investigated.
基金Project supported by Hunan Provincial Natural Science Foundation of China(2015JJ3004)National Natural Science Foundation of China(21276028)
文摘A series of fluorotellurite glasses based on（81–x）Te O2-（10＋x）KF-9La2O3（TKL）, where x=0 mol.%, 5 mol.%, 10 mol.%, 15 mol.%, doped with 2000 ppm Tm2O3, were prepared by the conventional melt quenching method.The influence of KF content on the thermal stability and optical spectroscopic properties of the Tm3＋ doped fluorotellurite glasses were investigated by differential scanning calorimetry（DSC）, X-ray diffraction（XRD）, density measurement, Fourier transform infrared spectroscopy（FTIR）, UV-VIS-NIR optical spectroscopy and fluorescence spectroscopy.Judd-Ofelt intensity parameters of Tm3＋ in as-prepared glasses were determined and used to calculate the spontaneous emission probabilities and the radiative lifetime for the 4f-4f transitions of the Tm3＋ ions.Stimulated emission cross sections in the 1470 nm region（σse） were evaluated by Füchtbauer-Ladenburg formula.The results showed that KF substitution of Te O2 was beneficial to improving the thermal stability, decreasing glass density and reducing the content of OH related groups for the investigated fluorotellurite glasses.The glass with composition of 66 Te O2-25KF-9La2O3（named TKL25） had the longest radiative lifetime of the 3H4（361 μs） and the largest FWHM×σse value（420.07×10–28 cm3）, which made it a promising material for S-band fiber amplifiers.
