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B.P. Chernyago A.I. Nepomnyashchikh G.I. Kalinovskii 《Russian Geology and Geophysics》2008,49(12):971-977
Relations between indoor and soil gas radon were experimentally studied in villages of the Baikal region. On the basis of the obtained data, the soil-to-indoor radon ratio was calculated, which can be used for prediction of radon pollution in buildings of the same kind. 相似文献
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Radon concentrations in high background radiation areas in the south are higher than those of others in China, especially ^220Rn concentration is significantly high. Therefore, measurements of ^222Rn and ^220Rn concentrations should be carried out there. This paper introduces a large size collector of radon progeny and its applications. The collector is a sheet of polyvinyl chloride fiber with electrostatics of (-500 V)-(-700 V). Its size (60 mm in diameter) is larger than those of others (26 mm in diameter) that work with the same principle. The collector is more effective to adsorb radon progeny than most of others. The equipment of ZnS(Ag) Scintillation Counting System is available for large size collectors to detect radon progeny. Therefore, its sensitivity of measurement is higher than that of others. According to the different half lives of radon progeny, and based on both theory and experiments, a formula for discrimination and calculation of ^222Rn and ^220Rn concentrations is deduced. The ^222Rn and ^220Rn concentrations were surveyed with electrostatic collectors of radon progeny on the campus of commercial school and some other areas in Hainan, southern China. Neither ^222Rn nor ^220Rn concentration was found significantly high. However, several faults underground were delineated. The collector is also used to study radon transportation. Results indicate that radon changes regularly with date when it has transported for a certain distance. Velocities of radon migration in the four media are quite different. Radon migrates more quickly in vertical tube than in the horizontal tube. 相似文献
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环境氡平衡因子问题的探讨 总被引:1,自引:0,他引:1
氡及其子体是人体受辐射危害的重要因素,而平衡因子是评价氡及其子体状态的重要参数之一。现就平衡因子进行了室内和室外的测量,对平衡因子的影响因素作了初步的探讨。 相似文献
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Correlation between geology and radon levels in groundwater, soil and indoor air in Bhilangana Valley, Garhwal Himalaya, India 总被引:2,自引:1,他引:2
Radon concentrations were measured in soil, air and groundwater in Bhilangana Valley, Garhwal Himalaya, India by using an
LR-115 plastic track detector and radon emanometer. Radon concentrations were found to vary from 1 KBq/m3 to 57 KBq/m3 in soil , 5 Bq/l to 887 Bq/l in water and 95 Bq/m3 to 208 Bq/m3 in air. The recorded values are quite high due to associated uranium mineralization in the area. Radon concentration was
also found to depend on the tectonic structure and geology of the area.
Received: 22 July 1996 · Accepted: 8 January 1997 相似文献
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介绍了活性炭法测量原理、采取的质量保障措施以及在尼日尔Teguidda地区砂岩型铀矿勘查中的应用情况。通过在已知铀矿床的试验和工作区的应用表明,活性炭吸附氡法对地表和浅层矿化点以及深层铀源都有很好的反映,并能指示断裂信息。该法可作为确定有利找铀地段的重要依据,对指导本区深部找铀具有重要意义。 相似文献
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在佳木斯城区地下热水调查中,运用了水中氡活度浓度测量和土壤氡活度浓度测量综合方法,有效地克服了城市地热地质调查中的不利因素。通过对水中氡活度浓度及土壤氡活度浓度测量值的正态化变换以及原始氡活度浓度异常分析,明确了氡活度浓度异常对地下热水控制构造的指示作用。通过对氡活度浓度测量值的趋势分析,提取局部异常,综合各种异常信息,确定了城区地下热水的有利远景区。 相似文献
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为了研究区域土壤氡填图的方法,利用RAD7电子测氡仪和RADON-JOK土壤气体渗透率仪在广东省中山市进行了面积为1 800 km2的测量工作,有效测点数为67个。中山市的平均土壤氡浓度为(100.41±154.64)kBq/m3;最大值和最小值分别为0.74 kBq/m3和1 199.24 kBq/m3。土壤气体渗透率测量结果表明,在风化花岗岩地区,高渗透率和中渗透率占优势;而第四纪沉积物地区大部分土壤气体渗透率较低。基于此,结合研究区土壤氡浓度和土壤气体渗透率,对研究区土壤氡风险进行了分级评价。为土壤氡风险分级的方法研究提供了有参考价值的研究实例。 相似文献
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Radon is a radioactive gas emanating naturally from uranium rich granites and shales. It may be emitted from the ground surface into the atmosphere as a gas, or it may be dissolved into stream water and transported over distance. The levels of radon gas in soils at ground surface depend on a number of factors relating to the source of the gas and to its transmission. Igneous rocks contain the highest mean concentrations of radium and uranium. The depth of cover is relevant also. Surveys over the years by the National Radiological Protection Board (NRPB) and others have indicated that the highest concentrations in the United Kingdom occur in Cornwall, Devon and northeast Scotland. However, recent reports have indicated that high concentrations of the gas may be detected in small pockets in counties outside of those considered at high risk. This survey relates to a series of measurements taken in and around Darlington, County Durham. The results showed the presence of small areas with strong concentrations of radon in soil gas, but only minor levels of dissolved gas in stream waters. 相似文献
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测氡技术在泉州清源山地下水源勘查中地应用 总被引:1,自引:0,他引:1
测氡是一种有效的放射性地球物理探测方法。由于含水裂隙基岩与其周边岩体的结构存在差异,氡气的浓度异常可间接反映出地质体裂隙系统的情况,并可分析其开启度、连通性,以及破碎程度。应用测氡技术对地下水资源进行勘探,对含水裂隙基岩的结构特征进行研究,能达到节约投资,缩短勘探时间的目的。并可与地质资料分析相互验证,为地下水勘察应用提供依据。这里将测氡技术应用于泉州市清源山地卞水资源勘探工作中,旨在寻找基岩山区地下水富集带。测氡结果显示,在清源山一带明显存在二条北西西向和北西向断裂,结合地质资料认为:F1断裂带和F2断裂带是地下水赋存的理想位置,而且这二条断裂延伸2.5km~3.0km,汇水面积大于13km^2,大气降水的补给能力5770m^3/d,每年的补给量可达211×10^4m^3。 相似文献
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Pressure of natural gas in its rock reservoir determines the final radon concentration in this gas after its decompression to normal conditions. In this investigation, radon contents of 62 natural gas samples were measured and a simple physical model of the gas reservoir was applied. The model takes into account an additional dependence of radon concentration on the natural gas pressure and on the porosity of the rock reservoir. The influence of the gas pressure on the value of the radon emanating power is discussed. The mean
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Ra content in the source rock needed for generation of
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Rn concentrations observed in gas is also calculated. The calculations are made with the help of regression analysis. 相似文献
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在广东珠海地区采用便携式半导体测氡仪进行了大比例尺土壤氡浓度调查,测点数469个,面积大于100km2。珠海地区地下0.6 m处的平均土壤氡浓度为55.94±58.54 kBq/m3,其中在珠海斗门的第四纪沉积物地区、沉积物和风化花岗岩混合地区,以及风化花岗岩地区的土壤氡浓度分别是7.14±8.75,37.64±25.92和151.25±196.23 kBq/m3。高氡潜势区主要分布在黑云母花岗岩、风化花岗岩地区和新的工业开发区,且表现出与当地岩性密切相关。城市化和工业化改变了原有的天然辐射背景。珠海市区的平均土壤氡浓度分别为广州、泉州和晋江市平均值的8.3倍和15倍。研究结果表明:珠海是一个氡潜势较高的区域,需要进一步开展辐射防护目的的氡测量。 相似文献
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云南省个旧地区氡地质填图测量方法比较分析 总被引:5,自引:1,他引:5
阐述了在云南个旧地区首次进行的氡地质填图试点工作,制定了以水系沉积物测量、土壤氡测量、地面γ能谱测量、室内γ能谱测量与地面氡析出率研究相结合的氡地质填图测量方法,以实测结果与已有水系沉积物资料分析相结合的方式,比较分析了该地区氡地质填图各种测量方法的有效性。 相似文献
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Indoor radon mapping and its relation to geology in Hungary 总被引:2,自引:0,他引:2
Mihály Minda György Tóth István Horváth Ivan Barnet Krisztián Hámori Eszter Tóth 《Environmental Geology》2009,57(3):601-609
Indoor radon mapping may show stronger dependence on geological formations if the measured homes are one-storied houses with
no basement. In Hungary, 17,244 homes were investigated on the yearly average of indoor radon concentrations; among these
homes, there were 6,154, one-storied, no-basement houses. In Hungary, 21 geological units were created relevant for indoor
radon index characterized by lithology, the position of the ground water table, and the gas permeability. Maps were drawn
of different topography (counties, grid, geological units) and different values (maximum, mean, indoor radon indexes). A kind
of standardization of houses was that only the one-storied, no-basement ones were chosen, but from geological point of view some more information was gained when the wall materials (bricks or adobe) were also taken
into account. (“Adobe” is made of clay and straw in Hungary, and not burned as brick, just dried on sunshine). Enhanced indoor
radon values can be observed on the bedrock of Cenozoic volcanic rocks and their eroded materials deposited on the local alluvial
valleys. Another group with relatively increased indoor radon values can be connected to granite bodies. The grid method is
useful for covering large state or even continental areas. For practical public use and detailed radon risk mapping geological
or administrative unit-systems could yield more reasonable and useful results. 相似文献