摘要
由原子武器和热核武器试验、核动力舰船运转、原子燃料工厂的生产所产生的放射性物质大部分进入海洋,致使海洋的放射性污染日益严重。这种状况将直接或间接地影响到人类的健康与安全。因此,对海洋放射性污染的研究具有重要的现实意义。目前,在海洋放射性污染的调查研究中,主要是调查锶-90、铯-137等,其分析方法探讨者较多,但对海水总β放射性的测定方法的报道却较少。
The method of determination of the gross beta radioactivity in sea water was studied using the radioactivity of fall-out as an isotopic tracer.Experiments showed that it was feasible to concentrate radionuclides in sea water with Barium chloride-Ferric ammonium alum.The related factors in this determination were studied and the results obtained are summarized as follows:1.The recovery of radioactivity varies with the changes of pH:20—30%is obtained with pH from 4.0 to 4.8,95%with pH 6.0—7.8,80%with pH 8.2—9.2,95%with pH 9.5 or over.The 70—80%recovery as reported by Miyake corresponds to that between pH 8.2 and pH 9.2,because at 9.5 or over a heavy whitish Mg(OH)precipitate formed makes the determination more difficult.although the recovery ob-tained may be hige.2.Heating increases the rate of recovery considerably.2—6 hours of settling after boiling give a recovery of 95%,while recovery is only 80%at 15—25%℃for the same period of settlement.A recovery of 88%was given at room temperature after standing for 24 hours.So the heating process may be omitted on shipboard.4.The effect of the amount of precipitant used on the recovery rate is to a considerable extent not appreciable.In order to increase the volume of sea water to be determined and save more time on determining,a minimum amount of precipitant to be used must be sought for.Experiments show that the addition of 2.5mg Fe^(+++)and 2.5mg Ba^(++)in 1 liter sea water may increase the amount of sea water from 1 to 4 liters,with recovery 88%as a checking reference.This method is simple enough to be used in determining the gross beta radioac-tivity in polluted sea water.
作者
李培泉
李金岭
Li Peiquan;Li Jinling(Institute of Oceanology,Academia Sinica)
出处
《海洋与湖沼》
1978年第1期43-48,共6页
Oceanologia Et Limnologia Sinica
