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1.
梁宝鎏  李冠球 《核技术》2001,24(12):988-995
在用前剂量法作古陶瓷真伪鉴定的过程中,需要对样本加入多次不同量值的剂量再进行激活及熄灭效应的测试,从而加大了测量误差值(通常都达20%-30%)。为了提高鉴定度,本文采用以固定剂量的熄灭效应作为参考值,以数学式子表面过程中发光强度的变化,并用几个测试序列作对比,找出比较理想的测试顺序,测量结果误差接近10%,远比原来方法优越,结论是此方法是可行的,但仍需作更多的实际测量工作来肯定。  相似文献   

2.
王猛  谷懿  卢恒  王浩  孙坤 《原子能科学技术》2020,54(7):1301-1307
本文基于石英热释光特性分析,通过实验方法分析石英在不同辐照剂量下375 ℃热释光峰的最佳预热温度和校正石英热释光灵敏度变化的最佳试验剂量,并依据实验结果对常规流程加以改进。最终,验证基于最优测量参数的改进流程对等效剂量测量准确度的提升。实验结果表明,若等效剂量较小,325 ℃热释光峰的信号较弱,选取较低的预热温度即可压制其对375 ℃热释光峰的影响。若等效剂量较大,则石英测片应先通过预热温度测试,根据再生剂量和试验剂量的最优预热温度进行等效剂量测量。石英测片再生剂量的取值处于0~1 000 Gy范围内时,200 Gy的试验剂量能对石英测片的热灵敏度变化起到校正作用,且10次重复测量结果的相对偏差小于5%。通过上述最优预热温度和试验剂量设置,分别降低325 ℃热释光峰残余信号干扰和校正石英热灵敏度变化。改进流程下400 Gy和700 Gy等效剂量测量值的相对偏差由常规流程的14.74%~47.15%和33.47%~197.71%均降低到±4%以内。本文为石英的375 ℃热释光峰年代测定准确度和年代测定范围的提升提供了重要参考依据。  相似文献   

3.
热释光断代的进展   总被引:1,自引:0,他引:1  
本文评述了热释光断代的近况。它们是:磷光体的热释光性质;关于发光中心;辐射剂量学,综述了五种测定年辐射剂量的方法,同时也讨论另两种测定氡逸散的方法;各种不同类型标本中累积辐射剂量的测定;热释光测量中的样品制备;辐射源及校正及其在热释光断代中的应用;测量热释光的装置。  相似文献   

4.
在进行考古测年时,沉积环境的地球化学变化可能会影响野外环境剂量率的测定,从而导致基于辐射暴露原理的测年方法结果的不准确性,如释光和电子自旋共振(ESR).实验通过对采自法国南部Arago洞穴中三种不同沉积环境下的同层牙齿样品进行ESR-U系联合法年代学分析,探讨了不同沉积环境及沉积环境的不均一性对测年结果产生的影响.其中出自石英矿物环境的样品年龄约为330 ka,而另两种不同沉积环境(碳酸盐和磷酸盐)下的样品年龄约480 ka,前者比后者年轻约150 Ka,这一现象可能是由于对石英矿物环境样品野外环境剂量率的高估造成的.  相似文献   

5.
表面TLD法测定瓷器的年剂量   总被引:1,自引:0,他引:1  
夏君定  王维达  梁宝鎏 《核技术》2001,24(12):1002-1005
用CaSO4:Tm超薄型热释光剂量片放在瓷器无釉或器物内部去釉后的部位,用表面TLD法测量瓷器样品中的年剂量,与α计数法及内部TLD法测得的瓷器年剂量值比较的结果表明,表面TLD技术能用于瓷器年剂量的测定,有助于提高TL测定瓷器年代的准确性,同样也适用于TL测定陶器的年代。  相似文献   

6.
In this paper, we used ESR dating method to measure the accumulative dose of the fossil teeth samples, which are contemporaneous with the Peking-Man. The internal annual dose rate of samples are got by neutron activation analysis and the environmental annual dose rate by highly sensitive TL dosimeters to be embedded in cave deposits in the site. The results of ESR dating are corresponded with the dating results obtained by U-series, FT, TL and paleomagnetic stratigraphical methods on the 3rd, 4th, 7th and 10th layers. Calculation of using different models, the close-equilibrium model, the linear uranium accumulation model and radon loss-linear uranium accumulation model, for travertine, deer teeth and rhinoceros tooth, we obtained the age of the First Peking- Man in the nth layer is 578 ka and gave ages of other layers, from the 1st to the 13th layer in Peking- Man site.  相似文献   

7.
EFFECTOFTHERATIOTh/UONTLDATINGACCURACY¥P.L.Leung(梁宝鎏);MichaelJ.Stokes(DepartmentofPhysicsandMaterialsScience,CityPolytechnico...  相似文献   

8.
梁宝鎏  夏君定 《核技术》1997,20(8):472-477
介绍了用多次激活法对许多样品进行热激活特征测定,比较了不同热激活温度对瓷器样品年代测定结果的影响。结果表明在多次激活中采用能使样品获得最高灵敏度的激活温度是十分重要的。  相似文献   

9.
细粒石英前剂量方法   总被引:5,自引:4,他引:1  
梁宝鎏  王维达 《核技术》1995,18(8):463-466
分析了前剂量技术的三种测量方法-多次激活,加剂量法和钉子技术的优缺点,并对细粒石英前剂量方法进行了专门研究。结果表明,细粒石英方法不仅简便,而且减少了多次激活,试验剂量和归一引起的误差,使最小可测年龄降至几十年。  相似文献   

10.
The firing temperature of ancient ceramic artifacts, i.e. the paleothermometry of these materials has been estimated by various techniques including thermoluminescence (TL) and, more recently, Optically Stimulated Luminescence (OSL) where the OSL response of quartz to firing temperature is used. In this work we report the paleothermometry of sodium chloride (NaCl) by studying the TL response of the material as a function of annealing temperatures in the range of 100–500 °C. Annealing/measurement has been done in a commercial TL/OSL reader (Model No. Risø TL/OSL reader TL-DA-15) in a nitrogen atmosphere.Sodium chloride (NaCl) has been selected as the candidate to test the feasibility of the technique since in this system TL peaks are correlated with the thermal annealing of F-centers unlike the case of quartz where a one to one correlation with all the glow peaks and thermal annealing of defects has not been possible.  相似文献   

11.
激光断代     
李虎候 《核技术》1991,14(2):94-100
  相似文献   

12.
本文描述了热释光(TL)和电子自旋共振(ESR)测年方法对剂量标定的若干要求。研究了~(90)Sr、~(90)Y在石英中各自的剂量占总剂量的百分比随深度的变化及该源照射不同大小颗粒石英时的平均剂量与表面(或参考点)剂量的关系。指出了忽略这一因素时所带来的误差的大小。  相似文献   

13.
采集湖光岩玛尔湖周围部分岩洞内的岩样及岩壁下和湖岸边的砂土样品,用粗颗粒法测量它们的热释光和光释光;用复合作用剂量响应模型分析热释光和光释光剂量响应,并计算对应的热释光和光释光古剂量。结果表明:相同采样点的样品,热释光和光释光古剂量间都存在一些差异;不同采样点样品的释光剂量相差很大;热释光古剂量测量值较准确的样品,光释光古剂量测量值与热释光测量值无显著的数量级差别。此测量分析对第四纪火山考古有一定参考意义。  相似文献   

14.
第四纪沉积物热释光测年中古剂量的测定方法   总被引:7,自引:1,他引:6  
卢演铸  张景昭 《核技术》1991,14(2):109-113
  相似文献   

15.
热释光方法在环境剂量监测中的应用   总被引:1,自引:0,他引:1  
天然热释光量和年剂量是热释光断代工作中两个重要参数,它们代表着标本周边环境的放射性辐射水平。实验数据表明,环境辐射水平受到基底岩性的控制影响。经过长期改造,地表环境辐射水平将逐步减弱并匀化。  相似文献   

16.
In this paper, the thermoluminescence (TL) dosimetric characteristics of Al-doped LiB3O5 compounds are presented. The powder samples were prepared by the solid-state reaction method and the formation of the compounds were confirmed by an X-ray diffraction study. The TL studies of undoped and Al-doped LiB3O5 samples showed similar glow curve structures. They have three TL glow peaks at about 60, 130 and 200 °C after heating at a constant heating rate of 1 °C/s. Their comparative TL studies indicated that 5 wt% Al-doped LiB3O5 compound was approximately 240 times more sensitive than undoped compound. The TL emission spectra of Al-doped LiB3O5 showed a maximum band at around 520 nm. The main dosimetric characteristics, which are namely the TL dose response, TL sensitivity, fading, minimum detectable dose, reproducibility, precision of dose measurement and annealing procedure, indicated that Al-doped LiB3O5 sample, can be used in dosimetric applications. The trap parameters namely order of kinetics (b), activation energy (E) and frequency factor (s) associated with the glow peaks in beta irradiated undoped and Al-doped LiB3O5 samples were obtained by glow curve deconvolution (GCD) program.  相似文献   

17.
The concept of measuring the reactivity as a procedure for correcting its computed values in an experiment is examined. The new one- and multi-point procedures for correcting the reactivity, which refine and develop existing procedures for minimizing the spatial and other parasitic effects preventing a reliable reactivity measurement, are formulated and validated.  相似文献   

18.
This paper presents an attempt to isolate experimentally optically stimulated luminescence (OSL) signals which may originate from very deep traps (VDT) in quartz samples. As VDT we consider those traps which are responsible for TL glow peaks with a peak maximum temperature above a TL readout temperature of 500 °C. The basic experimental procedure used to isolate OSL signals from VDT is heating the quartz samples to 500 °C immediately before measuring the OSL signal. The study was carried out on eight quartz samples of very different origins; it is found that all eight samples exhibit OSL signals from VDT, and for a wide region of OSL stimulation temperatures. The OSL signal from VDT depends strongly on the type of quartz sample studied and on whether the sample was fired at high temperatures or not. The behavior of the OSL signal from VDT as a function of the stimulation temperature is found to be very different in fired and unfired samples. The thermal activation energy E for the OSL signals from VDT is obtained in both fired and unfired samples. The OSL signal from VDT in quartz samples fired at 800 °C for 1 h is very high, and the OSL curves consist of three well-defined components and a fourth slow component which is rather poorly resolved. The dose response of these components is obtained using a computerized deconvolution procedure for the dose region 0.5-300 Gy. The results are of importance for dating of ancient fired ceramics, since OSL signals from VDT could potentially extend appreciably the equivalent dose region toward both lower and higher values.  相似文献   

19.
前剂量饱和指数法测定中国瓷器年代   总被引:11,自引:0,他引:11  
王维达  梁宝鎏  夏君定  周智新 《核技术》2001,24(12):996-1001
用前剂量饱和指数法测定了23件中国瓷器的年代,结果表明,热释光年代与考古年代在一个标准偏差为27%以内的一致性非常良好,这样的误差在瓷器的年代测定中是可以接受的。  相似文献   

20.
马宏林  周伟强  Martini M  Sibilia E 《核技术》1999,22(10):622-624
利用青铜器中残留的一些具有热释光特性的陶范或砂范对陕西出土的几件青铜器进行热释光测年研究,取得了满意的年代数据,测年精度一般都能达到8%-12%。由于本方法在陶范取样过程中一般不会对青铜器本体造成伤害,使得这一热释光测年及真伪鉴别法具有更广阔的应用前景。  相似文献   

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