226Ra decay chainchemical environmentRadioactive decay rates are to a large extent believed to be independent of the chemical environment. This is the physics basis implicitly assumed in applications such as radioisotope dating. While this statement is a good approximation for most radioactive decays,...
We hence demonstrate that an accurate determination of the decay constant has to consider the possible diffusion of volatile components in the decay chain. This is especially important in cases involving significant temperature change. 展开 关键词: Experimental/ nuclear electron capture radioactive dating...
The discovery of radioactive disequilibrium among isotopes of the 238 U decay chain in recent volcanic rocks 1鈥 7 has enhanced our understanding of both the timescale and processes of melting in the mantle. Excesses of 230 Th (half life 75,200 yr) relative to its parent 234 U in some ...
The apparent change of activity with temperature in a 226 Ra decay chain Radioactive decay rates are to a large extent believed to be independent of the chemical environment. This is the physics basis implicitly assumed in appli... J Thompson,N Luo,C Entenmann,... - 《Journal of ...
The improvements in the separation and pre-concentration techniques also helped to improve the 226Ra detection limit down to 0.05 fg/25 mL of groundwater sample.Background The radium-226, 226Ra (T ½ = 1622 years), is a naturally occurring radioisotope belonging to the 238U decay chain...
nu clid e d ecay chain ,the d etecti on resu lts were i n the range of the al lowabl e error and met the meas urement accuracy . K eyw or ds :Measurement ;Natural radionuclide;Decay chain;Shortest balance time;Gamma energy spectru m method 相关...
The different half-lives of the decay products of Ra and Ra allow the discrimination of these nuclides based on an electronic detection gateway pioneered in 1963 (Giffin et al. 1963). All events, including decays that cannot be attributed to either the Ra chain or the Ra chain, are counted...
Four α-particles are emitted in total per decay chain until a stable nuclide Pb-207 is formed. The absorbed doses in the cells and the hit distribution from the α-particles of all progeny from Ra-223 were calcu- lated by Monte-Carlo simulations, the doses from β- and γ-radiation ...
Measurements of the concentrations of the 238U decay series isotopes ( 234U, 230Th, 226Ra) have been used to estimate the rates at which magma is generated and transported in the mantle. The usual assumption is that solid mantle minerals are in radioactive equilibrium prior to melting. However...
In a similar manner to the Sr isotope system, it is possible to use radionuclides of the U and Th decay series for investigation of the interaction of different water components since there are several elements that are composed of two or more isotopes with half-lives long enough to survive ...