Radon leakage

Gilctti, B. and Kulp, J.L., 1955. Radon leakage from radioactive minerals. Amer. Mineral., 40 481-496. 

Venkatasubramanian, V. S. Studies on radon leakage in minerals. In Geophysical Exploration, A Symposium, Baroda, India, 1959, Proc. New Delhi, Council Sci. Indust. Res., 102—105 (1963). 

Figure 6 displays exhalation rate curves versus time for the sample in Figure 2, with the leakage factory as the variable parameter. Large leaks make the final steady-state exhalation rate deviate less from the free exhalation rate, in accordance with Equation 4. It must be remembered, however, that the radon activity accumulating in the outer volume is dependent on y, the exhalation rate is only the strength of the radon source feeding this volume. 

Radium. The radium source used in brachytherapy uses mostly radium sulfate or radium chloride mixed with an inert filler and loaded into cells about 1 cm long and 1 mm in diameter. These cells are made of 0.1- to 0.2- mm-thick gold foil. Radium sources are manufactured as needles or tubes in a variety of lengths and activities. Leakage of radon gas from a radium source represents a significant hazard if the source is broken. The sources are, however, doubly encapsulated to prevent such an occurrence. Cesium-137 has replaced radium, at least in the US. 

In a rock from the mid-Atlantic rise, the atomic ratio Pb/ U (corrected for Pb not generated by in the rock) is 1.128. (a) For every 1 mole of now present in the rock, how many moles were present when the rock was formed (b) Calculate the age of the rock, (c) See Fig. 25.5 (page 538). Does the leakage of radon from uranium minerals introduce a positive or a negative error in the age of the mineral ... 

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