Related Experiment Video
Updated: Aug 9, 2026

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
NIST 222Rn emission standards
1National Institute of Standards and Technology, Gaithersburg, MD 20899-0001, USA. peter.volkovitsky@nist.gov
Abstract:
NIST radon standards are hermetically sealed polyethylene capsules filled with 226Ra solution. Recently, four new series of standards with activities 5, 50, 500, and 5000 Bq were prepared. The measured emanation fraction agrees with a calculation that accounts for the radon accumulated inside the polyethylene walls of the capsule. Obtained solubility of radon in polyethylene is approximately 45 of the solubility of radon in water. The radon diffusion coefficient in low-density polyethylene is 7.2x10(-8)cm2/s.
Related Concept Videos
Types of Radioactivity
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
Radioactivity and Nuclear Equations
A nuclide of an element has a specific number of protons and...
Nuclear Stability
To hold positively charged protons together in the...
Nuclear Transmutation
Other Nuclides: 31P, 19F, 15N NMR
While fluorine-19 and phosphorous-31 have high natural abundances (100%) and positive gyromagnetic ratios, nitrogen-15 has a low natural abundance and a negative gyromagnetic ratio. However, nitrogen-15 is still preferred over nitrogen-14 (which has a high...
Radioactive Decay and Radiometric Dating

