Eu^(2+),Dy^(3+)and Zr_(4+)ions co-doped strontium aluminate(i.e.,SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Zr_(4+))/molybdate(i.e.,Ho2MoO6or Nd2MoO6)with photo-/mechano-luminescence and allochroic effect as multi-optical function...Eu^(2+),Dy^(3+)and Zr_(4+)ions co-doped strontium aluminate(i.e.,SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Zr_(4+))/molybdate(i.e.,Ho2MoO6or Nd2MoO6)with photo-/mechano-luminescence and allochroic effect as multi-optical functional hybrid pigments were prepared via solid state reactions and subsequent mixing.The phosphor and hybrid pigments were characterized by X-ray diffraction,scanning electron microscopy with energy dispersive X-ray spectroscopy,ultraviolet-visible spectroscopy,L*a*b*color scale analysis,spectrophotometry and mechanoluminescent measurement.The results show that the optimum luminescent emission intensity of SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Zr_(4+)phosphor can be obtained when 5 mol%Zr_(4+)ions is doped into the lattice.Under the excitation of 365 nm wavelength,the hybrid pigments prepared with the phosphor and molybdate at a mass ratio of 1:1 present a green broad band emission located at 460-650 nm due to 4f65d1→4f7transitions of Eu^(2+)ions.The hybrid pigments have the superior mechanoluminescent property and emit light after being exerted by mechanical stresses.Besides,the hybrid pigments also exhibit an allochroic effect under different illuminants.In addition,the anti-counterfeiting of the hybrid pigments as a promising application was also presented.展开更多
蓄热技术(thermal energy storage,TES)可有效改善建筑材料的热性能,用于TES的相变材料具有较高的储热量和良好的生物相容性,但导热系数低,传热效率不高。通过TES技术,以脱木素木材(delignified wood,DW)为载体,聚乙二醇(polyethylene g...蓄热技术(thermal energy storage,TES)可有效改善建筑材料的热性能,用于TES的相变材料具有较高的储热量和良好的生物相容性,但导热系数低,传热效率不高。通过TES技术,以脱木素木材(delignified wood,DW)为载体,聚乙二醇(polyethylene glycol,PEG)为储热材料,稀土铝酸锶(SrO·Al_(2)O_(3):Eu^(2+),Dy^(3+),SAED)为导热材料制备了不同SAED含量的新型木基复合材料,同时探究了SAED含量对木基复合材料热性能的影响,结合实际工艺建立了其储热过程的传热模型并进行求解。结果表明,40%SAED/PEG/DW的导热系数和升温速率相较于纯PEG/DW分别提高了57.14%和29.76%;建模求解纯PEG/DW,20%、30%和40%SAED/PEG/DW的储热过程,对比实际值和模拟预测值,其标准误差SE分别为1.35、1.92、1.73和1.35℃,预测误差PE分别为2.82%、-0.41%、-0.19%和-0.55%,模拟结果与实测结果吻合较好,可有效预测其储热过程的温度变化情况,用于指导实际生产。展开更多
The photoluminescence of Dy^(3+) doped and Dy^(3+), Ce^(3+) codoped in Ba_3La(BO_3)_3 were studied. The dependence of the charge-to-radius ratio (z/r) for RE^(3+)(RE=La, Ce), the Ce^(3+), Dy^(3+) content on the emissi...The photoluminescence of Dy^(3+) doped and Dy^(3+), Ce^(3+) codoped in Ba_3La(BO_3)_3 were studied. The dependence of the charge-to-radius ratio (z/r) for RE^(3+)(RE=La, Ce), the Ce^(3+), Dy^(3+) content on the emission intensity and the yellow to blue intensity ratio (Y/B) of Dy^(3+) were investigated too. The results obtained indicate that Ce^(3+) can sensitize the luminescence of Dy^(3+). The optimum concentration of Dy^(3+) in Ba_3La(BO_3)_3 is x_(Dy)=0.06. According to the dependence of the concentration of Dy^(3+) in Ba_3La(BO_3)_3 under the excitation of 350 nm, it is confirmed that the mechanism of concentration selfquenching of Dy^(3+) () (()~4F_(9/2)→()~6H_(15/2),) (()~6H_(13/2)) transition is electric dipole-quadrupole interaction.展开更多
In this paper,Dy^(3+)incorporated BaSi_(2)O_(5)phosphors were synthesized by gel co mbustion method and characterized by X-ray diffraction(XRD).The effects of various heating rate s on thermoluminescence(TL)kinetics a...In this paper,Dy^(3+)incorporated BaSi_(2)O_(5)phosphors were synthesized by gel co mbustion method and characterized by X-ray diffraction(XRD).The effects of various heating rate s on thermoluminescence(TL)kinetics and glow peak temperatures of Dy^(3+)incorporated BaSi_(2)O_(5)phosphors exposed toβirradiation at room temperature were investigated.The glow curves of the phosphor exposed toβ-irradiation(0.1-100 Gy)consist of four main peaks located at 87,130,271,and 327℃and exhibit a good linearity between 0.1 and100 Gy.Three experimental techniques including variable heating rate(VHR),repeated initial rise(RIR),peak shape(PS)and computerized glow curve deconvolution(CGCD)were employed to determine TL kinetic parameters.Our findings indicate that the TL glow peaks of the phosphor obey first-order kinetics.Analysis of the main dosimetric peaks through the techniques mentio ned above indicates that activation energies(E)and pre-exponential factor(s)are in the range of 0.80-1.50 eV and 1.15×10^(8)-3.28×10^(13)s^(-1).Additionally,it is found that the temperature of the glow peaks shifts toward the higher temperatures and the TL intensity smoothly decreases as the heating rate increases.The effect on the TL intensities and glow peak temperatu res of the heating rate is discussed in terms of thermal quenching.展开更多
In order to improve the red luminescent properties,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent lumin...In order to improve the red luminescent properties,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent luminescent spectra from blue to red.Composite red luminescent material Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)/light conversion agent(SMED/LCA)was fabricated with light conversion agent and Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)at a certain mass ratio.SiO_(2)(Al2 O_(3) or MgF2)were coated on the surface of SMED/LCA through heterogeneous deposition method.The structural and optical characteristics of the resulting samples were launched in terms of X-ray diffraction and emission spectrum as well as afterglow brightness.The results demonstrate that the emission spectrum exhibits two emission bands,and the peaks are located at around 470 and 615 nm.SiO_(2),Al_(2)O_(3) and MgF_(2) are coated on the surface of SMED/LCA like a protective shell to maintain its stability and luminescent properties,the afterglow initial brightness is still up to 0.37 cd/m^(2) and the afterglow color purity calculated from CIE color coordinates is basically unchanged.展开更多
基金supported by the National Natural Science Foundation of China(52072125)the Foshan Science and Technology Innovation Project,China(FSOAA-KJ419-4401-009)the Major Scientific and Technological Projects of Foshan,China(2016AG101415)。
文摘Eu^(2+),Dy^(3+)and Zr_(4+)ions co-doped strontium aluminate(i.e.,SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Zr_(4+))/molybdate(i.e.,Ho2MoO6or Nd2MoO6)with photo-/mechano-luminescence and allochroic effect as multi-optical functional hybrid pigments were prepared via solid state reactions and subsequent mixing.The phosphor and hybrid pigments were characterized by X-ray diffraction,scanning electron microscopy with energy dispersive X-ray spectroscopy,ultraviolet-visible spectroscopy,L*a*b*color scale analysis,spectrophotometry and mechanoluminescent measurement.The results show that the optimum luminescent emission intensity of SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Zr_(4+)phosphor can be obtained when 5 mol%Zr_(4+)ions is doped into the lattice.Under the excitation of 365 nm wavelength,the hybrid pigments prepared with the phosphor and molybdate at a mass ratio of 1:1 present a green broad band emission located at 460-650 nm due to 4f65d1→4f7transitions of Eu^(2+)ions.The hybrid pigments have the superior mechanoluminescent property and emit light after being exerted by mechanical stresses.Besides,the hybrid pigments also exhibit an allochroic effect under different illuminants.In addition,the anti-counterfeiting of the hybrid pigments as a promising application was also presented.
文摘蓄热技术(thermal energy storage,TES)可有效改善建筑材料的热性能,用于TES的相变材料具有较高的储热量和良好的生物相容性,但导热系数低,传热效率不高。通过TES技术,以脱木素木材(delignified wood,DW)为载体,聚乙二醇(polyethylene glycol,PEG)为储热材料,稀土铝酸锶(SrO·Al_(2)O_(3):Eu^(2+),Dy^(3+),SAED)为导热材料制备了不同SAED含量的新型木基复合材料,同时探究了SAED含量对木基复合材料热性能的影响,结合实际工艺建立了其储热过程的传热模型并进行求解。结果表明,40%SAED/PEG/DW的导热系数和升温速率相较于纯PEG/DW分别提高了57.14%和29.76%;建模求解纯PEG/DW,20%、30%和40%SAED/PEG/DW的储热过程,对比实际值和模拟预测值,其标准误差SE分别为1.35、1.92、1.73和1.35℃,预测误差PE分别为2.82%、-0.41%、-0.19%和-0.55%,模拟结果与实测结果吻合较好,可有效预测其储热过程的温度变化情况,用于指导实际生产。
基金National Natural Science Foundation of China(51872286,51832007)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR204)+1 种基金Science and Technology Plan Leading Project of Fujian Province(2022H0043,2020H0036)Natural Science Foundation of Jiangxi Province(20181BAB211009)。
文摘The photoluminescence of Dy^(3+) doped and Dy^(3+), Ce^(3+) codoped in Ba_3La(BO_3)_3 were studied. The dependence of the charge-to-radius ratio (z/r) for RE^(3+)(RE=La, Ce), the Ce^(3+), Dy^(3+) content on the emission intensity and the yellow to blue intensity ratio (Y/B) of Dy^(3+) were investigated too. The results obtained indicate that Ce^(3+) can sensitize the luminescence of Dy^(3+). The optimum concentration of Dy^(3+) in Ba_3La(BO_3)_3 is x_(Dy)=0.06. According to the dependence of the concentration of Dy^(3+) in Ba_3La(BO_3)_3 under the excitation of 350 nm, it is confirmed that the mechanism of concentration selfquenching of Dy^(3+) () (()~4F_(9/2)→()~6H_(15/2),) (()~6H_(13/2)) transition is electric dipole-quadrupole interaction.
基金Project supported by the Deanship of Scientific Research at Jazan University,the Kingdom of Saudi Arabia(W41-032).
文摘In this paper,Dy^(3+)incorporated BaSi_(2)O_(5)phosphors were synthesized by gel co mbustion method and characterized by X-ray diffraction(XRD).The effects of various heating rate s on thermoluminescence(TL)kinetics and glow peak temperatures of Dy^(3+)incorporated BaSi_(2)O_(5)phosphors exposed toβirradiation at room temperature were investigated.The glow curves of the phosphor exposed toβ-irradiation(0.1-100 Gy)consist of four main peaks located at 87,130,271,and 327℃and exhibit a good linearity between 0.1 and100 Gy.Three experimental techniques including variable heating rate(VHR),repeated initial rise(RIR),peak shape(PS)and computerized glow curve deconvolution(CGCD)were employed to determine TL kinetic parameters.Our findings indicate that the TL glow peaks of the phosphor obey first-order kinetics.Analysis of the main dosimetric peaks through the techniques mentio ned above indicates that activation energies(E)and pre-exponential factor(s)are in the range of 0.80-1.50 eV and 1.15×10^(8)-3.28×10^(13)s^(-1).Additionally,it is found that the temperature of the glow peaks shifts toward the higher temperatures and the TL intensity smoothly decreases as the heating rate increases.The effect on the TL intensities and glow peak temperatu res of the heating rate is discussed in terms of thermal quenching.
基金Project supported by Natural Science Foundation of Jiangsu Province(BK20171140,BK20180629)National Natural Science Foundation of China(51803076)。
文摘In order to improve the red luminescent properties,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent luminescent spectra from blue to red.Composite red luminescent material Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)/light conversion agent(SMED/LCA)was fabricated with light conversion agent and Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)at a certain mass ratio.SiO_(2)(Al2 O_(3) or MgF2)were coated on the surface of SMED/LCA through heterogeneous deposition method.The structural and optical characteristics of the resulting samples were launched in terms of X-ray diffraction and emission spectrum as well as afterglow brightness.The results demonstrate that the emission spectrum exhibits two emission bands,and the peaks are located at around 470 and 615 nm.SiO_(2),Al_(2)O_(3) and MgF_(2) are coated on the surface of SMED/LCA like a protective shell to maintain its stability and luminescent properties,the afterglow initial brightness is still up to 0.37 cd/m^(2) and the afterglow color purity calculated from CIE color coordinates is basically unchanged.
