论文标题
减少水样的体积以提高对铅污染的射击的灵敏度
Volume reduction of water samples to increase sensitivity for radioassay of lead contamination
论文作者
论文摘要
世界卫生组织(WHO)为饮用水铅的上限提出了10十亿ppb的10份。通常,要达到这种敏感性,需要昂贵的计量学。为了提高低成本设备的敏感性,本文探讨了使用掺杂铅210($^{210} pb $)的沸水样品的体积减少技术的前景,以增加溶质的浓度。 $^{210} $ pb是一种放射性铅同位素,可以用例如Boulby Underground锗套件的高纯净锗(HPGE)探测器。尚未检查接近WHO限制的浓度。本文介绍了$^{210} $ pb的数量减少技术的测量,从$ 1.9 \ times10^{ - 6} $ ppb开始减少,并导致$ 2.63 \ times10^{ - 4} $ ppb。这项工作还将量减少技术应用于伦敦自来水,并报告了HPGE探测器中伽马计数的射电测定结果。在其他放射性异位物中,$^{40} $ k,$^{210} $ pb,$^{131} $ i和$^{177} $ lu以$ 2.83 \ times10^{3} $ 2.55 \ ppb,$ 2.55 \ times10^times10^$ 2.55 \ \ 7} $ 10} $ 2.83 \ times10^{3} $ ppb,$ 2.83 \ times10^{3} $ 10}伦敦自来水样本中的PPB和$ 5.84 \ times10^{ - 10} $ ppb。该技术保留了$ 90 \ pm50 \%$ $^{40} $ k。在还原之前,以0.012 ppb的测量浓度从相同的水样品中推断出稳定的铅。
The World Health Organisation (WHO) presents an upper limit for lead in drinking water of 10 parts per billion ppb. Typically, to reach this level of sensitivity, expensive metrology is required. To increase the sensitivity of low cost devices, this paper explores the prospects of using a volume reduction technique of a boiled water sample doped with Lead-210 ($^{210}Pb$), as a means to increase the solute's concentration. $^{210}$Pb is a radioactive lead isotope and its concentration in a water sample can be measured with e.g. High Purity Germanium (HPGe) detectors at the Boulby Underground Germanium Suite. Concentrations close to the WHO limit have not been examined. This paper presents a measurement of the volume reduction technique retaining $99\pm(9)\%$ of $^{210}$Pb starting from a concentration of $1.9\times10^{-6}$ ppb before reduction and resulting in $2.63\times10^{-4}$ ppb after reduction. This work also applies the volume reduction technique to London tap water and reports the radioassay results from gamma counting in HPGe detectors. Among other radio-isotopes, $^{40}$K, $^{210}$Pb, $^{131}$I and $^{177}$Lu were identified at measured concentrations of $2.83\times10^{3}$ ppb, $2.55\times10^{-7}$ ppb, $5.06\times10^{-10}$ ppb and $5.84\times10^{-10}$ ppb in the London tap water sample. This technique retained $90\pm50\%$ of $^{40}$K. Stable lead was inferred from the same water sample at a measured concentration of 0.012 ppb, prior to reduction.