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Journal of Rare Earths 2009年第5期27卷 749-752页

作者：林林赵仲华张慰萍郑志强尹民 Department of Physics Fujian Normal University Department of Physics University of Science and Technology of China Department of Physics the City College of the City University of New York

A white long-lasting phosphor Ca2MgSi2O7:Dy3+ was prepared by the solid-state reaction. A strong band peaked at 260 nm was shown in the excitation spectrum of 578 nm emission, which might be attributed to the oxygen deficiency of the host. After irradiated with 254 nm for 4 min, the white afterglow of the sample could be seen for 3 h. Moreover, the depths and frequency factors of trap centers were calculated from the thermo-luminescence curve of the sample, which indicated that the trap centers corresponding to the 414 K band were more helpful to the long-lasting phosphorescence.

关键词： white long-lasting phosphor silicate dysprosium thermo-luminescence rare earths

Simultaneous determination of trap depth and the ratio of the rate of recombination to that of capture from thermo-luminescence

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Chinese Physics B 2006年第8期15卷 1883-1887页

作者：徐征张福俊赵谡玲王丽伟 A. N. Georgobiani V. B. Gutan 孟立建 Institute of Optoelectronics Key Laboratory of Luminescence and Optical Information Ministry of Education Beijing Jiaotong University Beijing 100044 China Departamento de Fisica Instituto Superior de Engenharia do Porto 4200-072 Porto Portugal P. N. Lebedev Physical Institute of Russian Academy of Sciences 117924 Moscow Russia

thermo-luminescence （TL） is a kind of luminescence decay measured with varying temperature. In the process of TL the decay parameter itself involves the temperature effect of traps. Thus the trap depth is inseparable from the decay parameter. There are two separate peaks in the TL curve of ZnS：Cu,Co if the measurement starts from liquid nitrogen temperature. In the experiment we started from zero Celsius temperature to isolate the deeper traps. We have proposed and realized three methods for simultaneous determination of trap depth and decay parameter based on the quasi-equilibrium model and experimental data. If we treat the case of kinetic order a = 1 as a = 2, the error might be as large as 100%.

关键词： thermo-luminescence trap depth monomolecular and bimolecular processes

ZnO and Zn1-xMnxO Minicrystal by CVT and Temporal Process of Photoelectrons

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Journal of Rare Earths 2006年第Z1期24卷 37-40页

作者： Dong Guoyi Lin Lin Zhang Xiaojun Wei Zhiren College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China

The ZnO and Zn1-xMnxO minicrystal were synthesized by chemical vapor transport (CVT). The electron trap structure (donor level) and process on the temporal behavior of photoelectrons of materials were respectively studied by thermo-luminescence and microwave absorption dielectric spectrometry. There are two peaks in the thermo-luminescence spectra in pure ZnO, one is -183 ℃ and the other is -127 ℃, which shows two kinds of electron trap energy level produced by the intrinsic defects in ZnO;but obtain very low thermo-luminescence that only equals to ten percent of pure ZnO in Zn1-xMnxO, which shows that its intensity of electron trap is less. The studies of microwave absorption dielectric spectrometry show that conduction band photoelectrons are two-step exponential decay process in ZnO, the lifetime of rapid process is 83 ns, while slow process is 828 ns, the reason of delay is relaxation effects of electron trap to conduction band photoelectrons. The intensity of electron trap is less in Zn1-xMnxO minicrystal, the relaxation effects of conduction band photoelectrons from electron trap is little, so electrons disappeared quickly at conduction band, and the decay process of photoelectrons is only 10～20 ns.

关键词： ZnO chemical vapor transport thermo-luminescence photoelectron

KCl:Eu^(2+) as a solar UV-C radiation dosimeter. Optically stimulated luminescence and thermoluminescence analyses

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Journal of Rare Earths 2009年第4期27卷 579-583页

作者： I.Aguirre de Cárcer H.L.D'Antoni M.Barboza-Flores V.Correcher F.Jaque Departamento Física de Materiales Universidad Autónoma Madrid Spain NASA Ames Research Center Moffett Field California USA Centro de Investig ción en Física Universidad de Sonora México Centro Investigaciones Energía y Medioambientales (CIEMAT) Madrid Spain

The KCI：Eu2＋ system response to UV-C was investigated by analyzing the optically stimulated luminescence （OSL） and ther- mo-luminescence （TL） signal produced by ultraviolet light exposure at room temperature. It was found that after UV-C ***, OSL was produced on a wide band of visible wavelengths with decay time that varied by several orders of magnitude depending on the Eu2＋ aggregation state. In spite of the low intensity of solar UV-C reaching the Earth＇s surface in Madrid （40° N, 700 m a.s.1.）, it was possible to measure the UV-C radiation dose at 6：48 solar time by using the TL response of the KCI：Eu2＋ system and differentiate it from the ambient beta radiation dose.

关键词： thermo-luminescence rare-earth-doped alkali halides solar ultraviolet dosimeter environmental radiation

A New Method of Calculating Trap Depth of Rare Earth Materials

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Journal of Rare Earths 2005年第6期23卷 672-675页

作者：王丽伟徐征滕枫姜薇薇张福俊孟立建 Institute of Optoelectronics Beijing Jiaotong University Beijing 100044 China Departamento de Fisica Instituto Superior de Engenharia do Porto Porto 4200-072 Portugal Postdoctoral Working Station of Tianjin University Postdoctoral Working Station of Zhong-huan San-Jin Ltd. Tianjin Economy and Technological Development Area Tianjin 300457 China Departamento

The mainly characteristic of trapping materials is the trap depth. So it is significant to calculate the trap depth for the trapping materials. A new method of calculating trap depth, which is based on energy band and using rate equations to analyze thermoluminescence, was brought forward. This method which uses the rate equations of the process and the thermoluminescence curve can replace traditional methods such as first order or second order kinetics. The trap depth of SrAl2O4：Eu^2＋ , Dy^3＋ and Sr4Al14O25：Eu^2＋ , Dy^3＋ was estimated from the glow curve. Then the numerical solution of the trap depth can be obtained. From the results of experiments and calculations, this method can accurately indicate the whole process.

关键词： luminescence kinetics thermo-luminescence trap depth rare earths

Roles of Eu^(2+), Dy^(3+) Ions in Persistent luminescence of Strontium Aluminates Phosphors

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Journal of Wuhan University of Technology(Materials Science) 2008年第5期23卷 652-657页

作者：吕兴栋 Academy of Functional Materials Jiangxi University of Finance and Economy

The polycrystalline Eu^2＋ and Dy ^3＋ co-doped strontium aluminates SrAl2O4： Eu^2＋, Dy^3＋ with different compositions were prepared by solid state reactions. The UV-excited photoluminescence, persistent luminescence and thermo-luminescence were studied and compared. Results show that the doped Eu^2＋ ion in SrAl2O4： Eu^2＋, Dy^3＋ phosphors works as not only the UV-excited luminescent center but also the persistent luminescent center. The doped Dy^3＋ ion can hardly yield any luminescence under UV-excitation, but effectively enhance the persistent luminescence and thermo-luminescence of SrAl2O4： Eu^2＋. Dy^3＋ co-doping can help form electron traps with appropriate depth due to its suitable electro-negativity, and increase the density and depth of electron traps. Based on above observations, a persistent luminescence mechanism, electron transfer model, is proposed and illustrated.

关键词： strontium aluminate persistent luminescence thermo-luminescence rare earthion

The Characteristics of Quartz Micro-morphology of The Fault Gouge in Bailongjiang Fault System and Its Chronology

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矿物学报 2013年第S1期33卷 80-80页

作者： SHEN Junfeng YANG Weimin LIU Ting HUANG Xiao ZHENG Weijie YU Lei WANG Guoqiang School of Earth Science and Resources CUGB Institute of Geomechanics CAGSMinzu University

A great deal of important information referring to fault motion (such as fault activities period, intensity, frequency, and even dynamic background, etc.) can be revealed by resolving fault gouge, which are the special result of fault motion while extruding or grinding. Based on the field investigation, collected from Bailongjiang fault system of Western Qinling Orogenic (QO) Belt, 44 samples of fault gouge were for quartz micro-morphology observation and statistics by the field emission SEM, and 14 samples were tested by thermo-luminescence dating. The results showed that most of the micro-morphology of quartz grains are fish scale and orange-haut fractures, but a small amount of moss-like, stalactitic, and subconchoidal fractures. Also very few decay of quartz grains and typical conchoids fracture quartz grains can be seen. This implied that the Bailongjiang fault system was motioned repeatedly in Quaternary period but main motion period was Pleistocene. 14 thermo-luminescence dating values showed herewith two groups as 343.29-184.06 ka and 92.18-13.87 ka. Therefore, the conclusions can be reached that the fault system were motioned starting at Pliocene epoch, frequently in the middle of Pleistocene (343.29-184.06 ka), and peak frequency in late Pleistocene (92.18-13.87 ka). The fault system motions have stopped at Holocene. The results are significant for the natural disaster risk evaluation in western QO region.

关键词： fault gouge quartz micro-morphology thermo-luminescence dating pleistocene Bailongjiang fault system