VUV spectroscopy and low temperature thermoluminescence of LSO:Ce and YSO:Ce

Radioluminescence and UV-excited photoluminescence spectra, photoluminescence time profiles, thermoluminescence glow curves and gamma-excited energy spectra (determining scintillation light yields) of several Lu₂SiO₅:Ce and Y₂SiO₅:Ce samples were recorded. The results are analyzed with attention focused on possible correlations between trap distributions, VUV responses, and light yields. The aspect of two distinct sites occupied by Ce³⁺ ions is also discussed.     

A novel bifunctional Dy3+ activated RbCaF3 single phase phosphor: Facile synthesis and dual-luminescence properties for WLEDs and dosimetry applications

A series of Dy³⁺ activated RbCaF₃ phosphors was synthesized by the conventional high temperature solid state reaction technique under ambient atmosphere. The structural properties and morphology of synthesized compounds were analyzed by PXRD and FE-SEM, respectively. The chemical composition of synthesized phosphors was obtained by EDAX. The phosphor was excited at 386 nm and monitored at 484 and 574 nm, and the strongest peak was located at 484 nm (blue region). In addition, the point of RbCaF₃:Dy³⁺ with calculated chromaticity coordinates in the CIE diagram was located in the yellow region. TL characteristics of the RbCaF₃:Dy³⁺ phosphor was analyzed and the glow curve peak was emitted at 355 K. The symmetry factor, Balarin parameter, activation energy and frequency factor were calculated by Chen method from the TL glow curve, and the TL signal degradation was also analyzed.     

LiF热释光剂量计对49．3MeVu12C离子束辐射的剂量响应初步研究

用LiF（M,Ti）热释光剂量计测量了兰州重离子研究装置提供的49．3MeV／u12C离子束辐射的剂量响应．结果发现,离子注量在1×107－2×108／cm2时,LiF对碳离子束的剂量响应效率η变化幅度不大,平均值为57％。提示LiF可用于一定离子注量范围内吸收剂量的测量,并且该结果与德国GSI通过重离子径迹结构理论模型计算得到的热释光剂量计对50MeV／u12C离子束的η＝54％基本一致。     

一种高热稳定性的热释光材料MgSO4：Dy，Mn

ＭｇＳＯ４：Ｄｙ,Ｍｎ的热释光发光曲线只有一个主剂量峰,采用热释光一般级动力学方程拟合发光曲线,确定热释光主剂量峰的峰参数和陷阱参数值,测定在０．１－２０ｋＧｙ剂量范围内用不同剂理＾６０Ｃｏγ射线照射ＭｇＳＯ４：Ｄｙ,Ｍｎ样品的热释光发光曲线,确定出热释光主剂量峰的平均峰温为－３８３．１℃,平均激活能为－１．９７２ｅＶ,频率因子的平均值为－４．２９４×１０＾１４ｓ＾－１及动力不级数≈２,并得到Ｍｇ     

Thermoluminescent behaviour of diamond films subjected to UV irradiation

The thermoluminescent behaviour of diamond films subjected to UV irradiation was studied by using an UV lamp of 254 nm wavelength. The UV irradiation was achieved by placing the samples 15 cm away from an UV source for different periods. The thermoluminescent signal was integrated from 0 to 350°C at a linear heating rate of 10°C/s in a N₂ atmosphere. The corresponding luminescence spectra show an excitation band centered at 450 nm while the emission band is centered around 500 nm at room temperature. The diamond films were synthesized on molybdenum substrates by the combustion flame technique and characterized by Raman spectroscopy and scanning electron microscopy. Received: 31 May 1999 / Reviewed and accepted: 22 July 1999     

铀矿勘查中热释光测量与航空γ能谱测量的对比研究

介绍了热释光测量方法在寻找砂岩型铀矿中的应用。经过在已知区、未知区的试验,以及与航空γ能谱测量的对比研究,可以认为热释光测量方法作为一种辅助的找铀手段,简便易行,在大面积覆盖区进行放射性测量找矿上,可以达到“破覆攻深”,快速揭示放射性元素在深部聚散程度的目的,显示出其明显的优势。     

热中子注量率测量方法研究

研究了金箔激活法和热释光法测量热中子注量率的方法,并对中国原子能研究院101重水反应堆某热中子通道热中子注量率的大小进行了测量,结果表明两种方法测量结果一致性很好,偏差仅为8．8％。     

Thermoluminescence response and trap features of gamma-irradiated Sr2Al2SiO7:Dy3+ phosphors

This study mainly focuses on the thermoluminescence features and trap parameter analysis of Sr₂Al₂SiO₇:Dy³⁺ phosphors prepared via the low-temperature combustion method. The phase confirmation, structural and morphological studies are performed using XRD, FTIR, SEM and EDX characterizations. The energy gap of pure and Dy³⁺ doped phosphors is calculated. And the band gap decrease with doping. The optimum concentration was 3 mol% from the emission spectra; hence, this sample was irradiated with 3 Gy–5 kGy gamma doses. The samples showed high sensitivity and the MDD value is 0.21 mGy. The trap parameters were determined following deconvolution of the glow curves. Four traps were found in the samples, and the trap lifetime increased with increasing gamma dose. The trap depth increased The linear response from 3 Gy to 250 Gy implies that the prepared samples could be used as γ dosimeters within this range.     

Thermoluminescence of cement

Cement is found to be a thermoluminescent material. The glow curves of ordinary portland cement obtained from two different sources are found to be qualitatively similar. White cement (J K Brand) exhibits intense thermoluminescence (TL) compared to Birla white brand. The emission of J K white cement seems to be mainly due to Mn impurities which enters the product through limestone, the major ingredient in the preparation of cement. The possible use of TL as a spectroscopic technique to characterize cement is discussed.