Abstract In order to evaluate the radiological baseline in the Lake Van basin, 238U, 232Th, 226Ra, 137Cs and 40K activity concentrations and gross radioactivity were determined in twelve river water and sediment samples. To determine radionuclide activities and gross radioactivity, a gamma ray spectrometer with HPGe detector and a gross-alpha/beta-counting system low background multi-detector were used, respectively. Therefore, based on the measured activity concentrations, parameters of radiological hazards such as radium equivalent activity, outdoor absorbed dose rate, annual effective dose, and internal and external hazard indices were calculated. Req, Hex and Hin values in samples were generally lower than worldwide average values; while Dout and AED values were higher than worldwide average values in general.

中文翻译：

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河水和沉积物中天然和部分人工放射性核素的环境危害参数评价

摘要 为了评价万湖流域的放射性基线，测定了12个河水和沉积物样品的238U、232Th、226Ra、137Cs和40K活度浓度和总放射性。为了确定放射性核素活度和总放射性，分别使用了带有 HPGe 探测器的伽马射线能谱仪和总α/β 计数系统低背景多探测器。因此，根据实测的活度浓度，计算出镭当量活度、室外吸收剂量率、年有效剂量、内外危害指数等放射危害参数。样本中的 Req、Hex 和 Hin 值普遍低于全球平均值；而 Dout 和 AED 值总体上高于全球平均值。