最新刊期
卷 0 ， 期 0 ， 2020
- 摘要：<正> 在中国岩石矿物地球化学学会大力支持下, 由云南省地震局主办的全国第二次热释光与电子自旋共振测定年代学术讨论会于1990年5月7—12日在昆明召开。本选编辑录了讨论会中的14篇论文。
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发布时间：2021-04-20 - 摘要：ESR dating method and the age determination of the first skull of Zhoukoudian Pe king-Man have been introduced in this paper. Some animal fossil teeth, which are contemporaneous with the Peking-Man, were used for determination of accumulative dose. The in-ternal and environmental doses of the tooth samples were determined by neutron activation analysis and embeded thermoluminescence dosimeter at the site, respectively. The age of 578 ka of the first skull of Peking-Man is calculated by the linear uranium accumulation model. According to the ESR dating results, we have given a chronological scale of the cave deposits Loc. 1, Peking-Man site and discussed the mean-life of trapped electron for dating.
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发布时间：2021-04-20 - 摘要：On the basis of studies on elephant tooth fossil, ESR dating of elaphurus davidianus horn fossil found in Anhui Province was reported. The sample examined by TEM electron spectrum is composed of hydroxyapatite. ESR experiments showed that the solid bone sam-pk can be chosen as dating material. According to the contents of U, Th and K in the sample determined by ICP, the annual dose of radiation was calculated using the linear uranium accumulation model and disequilibrium decay. The age of this fossil was determined to be 2.5 × 104 years.
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发布时间：2021-04-20 - 摘要：It was found that K value can be reflected by the ratio of natural ESR signal intensity I0 to the maximum ESR signal intensity 1mai at dose saturation. An equation of assessment of K. value, derived from several samples of aragonitic corals compared with U-series dating, was obtained. The precision of ESR datimg can be improved using the equation.
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发布时间：2021-04-20 - 摘要：ESR dating has been applied to study landslides. A method of dose difference to determine the landslide age has been developed. The ESR spectra of annealled quartz grain samples and the optimum conditions of thermal activation were studied. The significance of ESR dating of landslide in geological research was discussed.
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发布时间：2021-04-20 - 摘要：ESR dating methods were used to determine the formative ages of two different kinds of loess sections. The ESR ages of aeolian loess are consistent with the magnetostratigra-phic, and the ESR ages of eluvial loess are in agreement with the weathering law.
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发布时间：2021-04-20 - 摘要：The effect of various light irradiations on E’ centre signal amplitude was studied and its influence on the ESR dating was discussed.
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发布时间：2021-04-20 - 摘要：The alanine/ESR dosimeter and its calibration are described. The sample preparation, the procedure for absorbed dose determination by measuring the free radical number in irradiated alanine samples with an ESR spectrometer, and the metrological properties of the dosimeter are also presented. Finally the application of this dosimeter to ESR dating and to unifying the value of absorbed dose for γ-rays is introduced.
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发布时间：2021-04-20 - 摘要：Optical dating is a new, and as yet at experimental stage, technique for the direct dating of sediments. As in the TL dating, the zeroing mechanism in optical dating is exposure to light. While in TL dating the paleodose is measured by heating the minerals, in optical dating this is done by exposing the minerals to monochromatic light, e. g. the 514nm green wavelength emitted by an argon ion laser. In optical dating, the light is used to measure the trapped electron population, an which only the electrons accumulated in light-sensitive elec-tron traps and assumed to be completely emptied by sunlight during the process of deposition, are measured. Thus, the zeroing problem can be basically solved by sunlight bleaching in the sediment dating.
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发布时间：2021-04-20 - 摘要：The thick source alpha counting in TL and ESR dating is described. A major advantage of using this method for the determination of annual alpha dose is that, the counting rate can be put directly into the age equation, thus not necessary to go through calculations which involve Th and U concentrations and dose-rate conversion factors. When alpha coun-ting is used to assess the beta and gamma annual dose the equal Th and U activities must be assumed or the components of Th and U should be separated using the ’pairs’ technique.
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发布时间：2021-04-20 - 摘要：Determination of the paleodose absorbed by debris minerals in sediments after deposition is a key course for TL dating of the Quaternary sediments. Three methods, i.e. the partial bleaching, the residual and the regeneration TL method, have been widely employed for paleodose measurement. On the basis of the paleodose determinations of more than one hundred samples of loess, sand dune and alluvial deposits obtained by these methods we come to the conclusion that （1） the par-tial bleaching method seems to be unsuitable for aeolian deposits, such as loess and sand dune;（2） the residual TL method is simpler and more reliable, especially for younger aeolian deposits; and （3） although the regeneration TL method takes long time, it is a reliable way for samples with nonlinear TL growth curve.
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发布时间：2021-04-20 - 摘要：The effective alpha annual dose is usually evaluated by using a K-value system. But the measured value of K is strongly dependent on the energy of the alpha particles used for measurement. This drawback is avoided in the a-value system, which is based on the experimental fact that the TL per unit length of track is approximately independent of particle energy. Thus, we can specify alpha sensitivity in terms of TL per unit length of track and calibrate alpha source in terms of the length of track delivered per unit volume of sample. In a-value system the effective alpha annual dose is obtained directly from alpha count rate.
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发布时间：2021-04-20 - 摘要：The distribution feature of Icess along the north boundary of Qilianshan Mountain in the last late-Pleistocene to Holocene and the TL age was described. According to the TL age cf the loess, it is inferred that the formation age of the third terrace is a little more than 14 ka and the holizontal dislocated rate in average is 1.5 mm/a in Xiaociyaokou segment of Yumushan Fault.
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发布时间：2021-04-20 - 摘要：How to calculate the linear fitting error for equivalent β dose evaluation is described; The authors hold that the evaluation of total error on TL dating must contain the linear Jitting error, which is specially important in geological sample measurements.
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发布时间：2021-04-20 - 摘要：Based on a study of the existing problems found in the vacuum glow-ovens now used in TL laboratories, the author has developed a new system with some improvements. Some implements with better performence and practical significance are also presented.
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发布时间：2021-04-20 - 摘要：<正> 1.陈丽姝（中国原子能科学研究院）和橘宏行（日本原子力研究所）:温度对电子自旋共振剂量计的影响。 2.韩道山（地矿部岩溶地质研究所）:桂林茅茅头大岩石笋的ESR年代研究。 3.薛鸿庆（上海测试技术研究所）和白益华（上海计量技术研究所）:粉末丙氨酸/ESR剂量测定法。 4.白益华（上海计量技术研究所）:粉末型丙氨酸/ESR剂量计——剂量学性能研究 5.薛鸿庆（中国上海测试中心）和张寿越（中国科学院地质研究所）:洞穴钙质沉积物ESR年龄测定研究——用天然内标法测定天然累积剂量
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发布时间：2021-04-20
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