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Gallium-70 can decay through both beta minus decay and electron capture. Gallium-67 is unique among the light isotopes in having only electron capture as a decay mode, as its decay energy is not sufficient to allow positron emission. [31] Gallium-67 and gallium-68 (half-life 67.7 min) are both used in nuclear medicine.
Relative abundance of elements in the Earth's upper crust In physics , natural abundance (NA) refers to the abundance of isotopes of a chemical element as naturally found on a planet . The relative atomic mass (a weighted average, weighted by mole-fraction abundance figures) of these isotopes is the atomic weight listed for the element in the ...
Gallium-67 (half-life 3.3 days) is a gamma-emitting isotope (the gamma ray emitted immediately after electron capture) used in standard nuclear medical imaging, in procedures usually referred to as gallium scans. It is usually used as the free ion, Ga 3+. It is the longest-lived radioisotope of gallium.
The Earth's crust is one "reservoir" for measurements of abundance. A reservoir is any large body to be studied as unit, like the ocean, atmosphere, mantle or crust. Different reservoirs may have different relative amounts of each element due to different chemical or mechanical processes involved in the creation of the reservoir.
China on Tuesday banned exports to the United States of the critical minerals gallium, germanium and antimony that have widespread military applications, escalating trade tensions the day after ...
The abundance of elements in the Sun and outer planets is similar to that in the universe. Due to solar heating, the elements of Earth and the inner rocky planets of the Solar System have undergone an additional depletion of volatile hydrogen, helium, neon, nitrogen, and carbon (which volatilizes as methane). The crust, mantle, and core of the ...
The reason is that there is no primordial helium in the atmosphere; due to the small mass of the atom, helium cannot be retained by the Earth's gravitational field. [71] Helium on Earth comes from the alpha decay of heavy elements such as uranium and thorium found in the Earth's crust, and tends to accumulate in natural gas deposits. [71]
A.B. Ronov, A.A. Yaroshevsky, Earth's Crust Geochemistry, in Encyclopedia of Geochemistry and Environmental Sciences, R.W. Fairbridge (ed.), Van Nostrand, New York, (1969). Estimated abundance of the elements in the continental crust (C1) and in seawater near the surface (W1). The median values of reported measurements are given.