临潼5号矿泉水年龄的初步测定

Preliminary determination of age of lintong No 5 mineral spring Water

目的测定临潼５号矿泉水的年龄。方法用配有多道谱仪的低本底液体闪烁计数器，测定地表水与矿泉水的氚活度。矿泉水的年龄可按公式ｔ＝（Ｔ／０．６９３×Ｌｎ（Ｎｏ／Ｎ）计算，式中ｔ—矿泉水的年龄，Ｔ—氚半衰期，Ｎｏ—地表水氚活度，Ｎ—矿泉水氚活度。结果地表水与矿泉水的氚活度分别为２７３ｃｐｍ／ｇ与１８０ｃｍｐ／ｇ，已知的氚半衰期为１２３年，于是ｔ＝（１２．３／０．６９２）×Ｉｎ（２．７３／１．８０≌７４年。结论临潼５号矿泉水的年龄约为７４年，此参数对于矿泉水的开发将是有用的。

Objektive To determine the age of Lintong No 5 mineral spring water. Methods The activity of tritium in surface water and in mineral spring water were measured using low background liquid scintillation counter matched with multichannel spectrograph.The age of mineral spring water may be evaluated by means of formual t=(T/0.693)×ln(No/N).where t-age of mineral spring water,T-half life of tritium,No-activity of tritium in surface water,N-activity of tritium in mineral spring water. Results The activity of tritium in surface water and in mineral spring water were 2.73cpm/g and 1.80 cpm/g respectively.The half life of tritium is known to be 12.3 yr,then t=(12.3/0.693)×ln(2.73/1.80)≌7.4 yr. Conclusions The age of Lintong No 5 mineral spring water is about 7.4 yr.This parameter will be useful in devolopment of mineral spring water.