Later, Hevesy and Lgstrup (,, p. 1; 1928) showed experimentally that the radioactivity of potassium appears to be confined to the isotope of mass 41; Aston had previously shown that potassium consists of two isotopes of masses 39 and 41. If only the isotope of mass 41 is radioactive,...
Each mineral contained approximately 9 per cent KO and less than 0.3 per cent CaO, so that there seemed reasonable grounds for hope that the accumulation of the calcium isotope with mass 41, through the slow radioactive disintegration of the potassium in the deposit, might be sufficient to ...
The most important natural radioactive isotope in the hydrosphere is 40K, which, in the form of a potassium ion, is mostly found dissolved in water. Because of the lower salt concentration, the radioactivity of rivers is much less than that of seawater. For example, the mean radioactivity of...
Radioactivity in minerals are caused by the inclusion of naturally-occurring radioactive elements in the mineral’s composition. The degree of radioactivity is dependent on the concentration and isotope present in the mineral. For the most part, minerals that contain potassium (K), uranium (U), a...
3 THE RADIOACTIVE ISOTOPE DEPARTMENT The protection problems associated with the clinical use of radioactive isotopes are quite different from those which are met in either type of X-ray department. This is because radiation is emitted continuously from radioactive materials—it can never be swit...
Radioactivity in mineralsare caused by the inclusion of naturally-occurring radioactive elements in the mineral’s composition. The degree of radioactivity is dependent on the concentration and isotope present in the mineral. For the most part, minerals that contain potassium (K), uranium (U), and...
Examples of Radioactive Dating and Isotopes The following are some isotopes used in dating: Carbon-14is a specific isotope used in dating items that used to be alive. Uranium-238is an isotope with a half-life of 4.5 years. Other isotopes include uranium-235, potassium-40, and iodine-131....
Beta-decay or β decay represents the disintegration of a parent nucleus to a daughter through the emission of the beta particle. Beta particles are high-energy, high-speed electrons or positrons emitted by certain radioactive nuclei such as potassium-40. The beta particles have a greater ra...
Beer is not particularly radioactive, but a single beer does contain, on average, about 390 pCi/kg ofthe isotopepotassium-40. All foods which contain potassium have some of this isotope, so you could sort of consider this a nutrient in beer. Of the items on this list, beer probably is...
Benno, D.: Isotope radiographs for localization of renal calculi during surgery: A new truly portable radiographic unit using a radioisotope (thulium-170) as ergy source. J. l col. (Baltimore) 76, 508–519 (1956). Care, A. D.: Ionic migration across the nmcosa of the small intestine ...