We report a simple new technique for measuring low-level radium isotopes (224Ra and 226Ra) in natural waters. The radium present in natural waters is first preconcentrated onto MnO2-coated acrylic fiber (Mn fiber) in a column mode. The radon produced from the adsorbed radium is then circulated through a closed air-loop connected to a commercial radon-in-air monitor. The monitor counts alpha dec...

toward march 1970 up to may 1972 it was monthly measured the radium quantity, available in, tehran milk, fortunate1y the results were in accordance to a reasonable value. the only remarkable point was that in wintertime, the indio activity decreased to minimum of 0.02 pci/lit, and in spring time it went up to a maxi­mum of 0.09 pci/lit. the next note worthy point was observed in a special conta...