【摘 要】
：
The long afterglow phosphor CaAl2O4:Eu2+,Nd3+ was prepared by the high temperature solid-state reaction method,and the influence of La3+ and Dy3+ on the propert
【机 构】
：
National Engineering Research Center for Rare Earth Materials
【基金项目】
：
国家自然科学基金;国家高技术研究发展计划(863计划)
论文部分内容阅读
The long afterglow phosphor CaAl2O4:Eu2+,Nd3+ was prepared by the high temperature solid-state reaction method,and the influence of La3+ and Dy3+ on the properties of the long afterglow phosphor was studied by X-ray diffraction (XRD),photoluminescence (PL),and thermoluminescence (TL),The XRD pattern shows the host phase of CaAl2O4 is produced and no impurity phase appears.The peak wavelength of the phosphor does not vary with La3+ and Dy3+ doping.It implies that the crystal field,which affects the 5d electron states of Eu2+ is not changed dramatically after doping of La3+ and Dy3+.The TL spectra indicate that the phosphor doped with La3+ or Dy3+ produces different depths of trap energy level.In the mechanism of long afterglow luminescence,it is considered that La3+ or Dy3+ works as trap energy level.The decay time lies on the number of electrons in the trap energy level and the rate of the electrons returning to the excitation level.
其他文献
In the light of the localized progressive damage model, the evolution law of cohesive and frictional strength with irreversible strains was determined. Then, th
Fe-Cr-Mo-Ni-C-Co alloy was quenched in liquid nitrogen and held for 24 h. Hardness tester, OM, XRD, SEM were used to investigate the mechanical properties and m
The multivalued general mixed implicit equilibrium-like problems are introduced and studied.To solve these problems,a new predictor-corrector iterative algorith
Based on the problem that the service entity only has the partial field of vision in the network environment, a trust evolvement method of the macro self-organi
Two thermomechanical coupled elastic-plastic finite element (FE) models were developed for predicting the 12-pass continuous rolling process of GCr15 rod and wi
The electrochemical behaviors of n-type silicon wafers in silica-based slurry were investigated, and the influences of the pH value and solid content of the slu
The cathode materials LiMn204 and rare earth elements La-doped or La and F dual-doped spinel lithium manganese oxides were synthesized by the citric acid-assist
In order to obtain a new precursor for LiFePO4, Fe2P2O7 with high purity was prepared through solid phase reaction at 650 ℃ using starting materials of FeC2O4
Current grid authentication frameworks are achieved by applying the standard SSL authentication protocol(SAP).The authentication process is very complicated,and
A new method for parameter optimization of pharmacokinetics based on an artificial immune network named PKAIN is proposed.To improve local searching ability of