Ravisankar R, Vanasundari K, Suganya M, Raghu Y, Rajalakshmi A, Chandrasekaran A, Sivakumar S, Chandramohan J, Vijayagopal P, Venkatraman B
Post Graduate and Research Department of Physics, Government Arts College, Tiruvannamalai 606603, Tamilnadu, India.
Post Graduate and Research Department of Physics, Government Arts College, Tiruvannamalai 606603, Tamilnadu, India.
Appl Radiat Isot. 2014 Feb;85:114-27. doi: 10.1016/j.apradiso.2013.12.005. Epub 2013 Dec 25.
Using γ spectrometry, the concentration of the naturally occurring radionuclides (226)Ra, (232)Th and (40)K has been measured in soil, sand, cement, clay and bricks, which are used as building materials in Tiruvannamalai, Tamilnadu, India. The radium equivalent activity (Raeq), the criterion formula (CF), indoor gamma absorbed dose rate (DR), annual effective dose (HR), activity utilization index (AUI), alpha index (Iα), gamma index (Iγ), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the building materials. From the analysis, it is found that these materials used for the construction of dwellings are safe for the inhabitants. The radiological data were processed using multivariate statistical methods to determine the similarities and correlation among the various samples. The frequency distributions for all radionuclides were analyzed. The data set consisted of 15 measured variables. The Pearson correlation coefficient reveals that the (226)Ra distribution in building materials is controlled by the variation of the (40)K concentration. Principal component analysis (PCA) yields a two-component representation of the acquired data from the building materials in Tiruvannamalai, wherein 94.9% of the total variance is explained. The resulting dendrogram of hierarchical cluster analysis (HCA) classified the 30 building materials into four major groups using 15 variables.
利用γ能谱法,测定了印度泰米尔纳德邦蒂鲁瓦纳马莱用作建筑材料的土壤、沙子、水泥、粘土和砖块中天然存在的放射性核素(226)镭、(232)钍和(40)钾的浓度。计算了与天然放射性核素相关的镭当量活度(Raeq)、标准公式(CF)、室内γ吸收剂量率(DR)、年有效剂量(HR)、活度利用指数(AUI)、α指数(Iα)、γ指数(Iγ)、外照射危害指数(Hex)、内照射危害指数(Hin)、代表性水平指数(RLI)、超额终生癌症风险(ELCR)和年性腺剂量当量(AGDE),以评估建筑材料中天然放射性的辐射危害。通过分析发现,这些用于建造住宅的材料对居民来说是安全的。使用多元统计方法处理放射学数据,以确定各种样品之间的相似性和相关性。分析了所有放射性核素的频率分布。数据集由15个测量变量组成。皮尔逊相关系数表明,建筑材料中(226)镭的分布受(40)钾浓度变化的控制。主成分分析(PCA)对来自蒂鲁瓦纳马莱建筑材料的采集数据给出了双组分表示,其中解释了总方差的94.9%。层次聚类分析(HCA)得到的树形图使用15个变量将30种建筑材料分为四大类。