Beta-energy emitting isotopes

These are mostly used for counting beta-energy-emitting isotopes, such as tritium 3H and 14C-(Carbon-14) isotopes. 

TABLE 3-3. Percent Occurrence and the Energies of the Major Alpha and Beta Particles Emitted by Thorium Isotopes With Atomic Masses Ranging from 223 to 234 ... 

This experiment examines the self-absorption of the beta particles emitted by 40K (t1/2 = 1.28 x 109 a, Emax = 1.311 MeV, 89.3%), a naturally-occurring isotope of potassium (abundance = 0.0117%), in potassium chloride (KC1) salt. The degree of beta-particle self-absorption (including self-scattering) depends on the energy of the beta particles, the sample matrix elemental... 

D. The external radiation hazard from exposure to tritium is extremely small, because the beta particles emitted cannot penetrate the dead layer of skin. However tritium is easily internalized through inhalation and absorption through the skin. The low energy beta radiation from the tritium is an internal hazard only (i.e., the isotope must get inside your body to cause damage). 

Pure beta-emitting isotopes exist and may be used for calibration, but only after the energy spectrum is cast into a form called the Kurie plot. The beta spectrum is continuous and extends from zero energy up to a maximum end point kinetic energy (see Fig. 13.12). Because of the shape of the spectrum, it is impossible to accurately determine the end point energy. However, from the... 

The appropriate average beta and gamma energies emitted per disintegration, as given in the Table of Isotopes, Sixth Edition, by C.M. Lederer, J.M. Hollander, 1. Perlman University of California, Berkeley Lawrence Radiation Laboratory should be used, (g) For BWRs with stacks the atmospheric diffusion model should be as follows ... 

Radiopharmaceuticals for use in therapy should have a long retention time and be highly selective. Low-energy beta emitting isotopes are used (e.g., iodine ( I)). Some high-energy beta emitters (yttrium ( °Y), phosphorus ( P)) and alpha emitters (bismuth ( Bi)) are also used. 

With beta emitting isotopes, the meter reading to surface activity ratio is sensitive to the beta energy which... 

The methods for detection and quantitation of radiolabeled tracers are deterrnined by the type of emission, ie, y-, or x-rays, the tracer affords the energy of the emission and the efficiency of the system by which it is measured. Detection of radioactivity can be achieved in all cases using the Geiger counter. However, in the case of the radionucHdes that emit low energy betas such as H, large amounts of isotopes are required for detection and accurate quantitation of a signal. This is in most cases undesirable and impractical. Thus, more sensitive and reproducible methods of detection and quantitation have been developed. 

Radioactive isotopes that decay by the emission of alpha or beta radiation undergo a change in the nature of their nuclei and are converted into isotopes of other elements. The emission of gamma rays, on the other hand, does not change the nature of the nuclei of the radioisotopes from which the rays are emitted. Gamma rays are a form of dissipation of nuclear energy. 

The finely-powdered metal is pyrophoric. Its radioactive isotopes Sr-89 and Sr-90 emit high-energy beta radiation. They are extremely hazardous because they deposit in bones replacing calcium. Their radiation can damage bone marrow and blood-forming organs, inducing cancer. 

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