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...

The abundance of the chemical elements is a measure of the occurrence of the chemical elements relative to all other elements in a given environment....

H NMR for materials of natural abundance. Singleton and coworkers demonstrated the capacity of 13 C NMR based natural abundance KIE measurements for studying...

elements are Natural abundance, the natural prevalence of different isotopes of an element on Earth Abundance of elements in Earth's crust Abundance (novel)...

3He fraction. 3He is also present in the Earth's atmosphere. The natural abundance of 3He in naturally occurring helium gas is 1.38×10−6 (1.38 parts...

Relative abundance can refer to Relative species abundance in ecological communities. Natural abundance of isotopes of a chemical element in nature. This...

more common protium has no neutrons in the nucleus. Deuterium has a natural abundance in Earth's oceans of about one atom of deuterium among every 6,420...

decays. Iridium-192 is normally produced by neutron activation of natural-abundance iridium metal. Iridium-192 is a very strong gamma ray emitter, with...

more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and Jupiter, because of the very high...

Greece of earth, water, air or fire Natural abundance, the relative amounts of isotopes of a chemical element Abundance of the chemical elements, the relative...

DuBois, Jennifer L.; Ojha, Sunil (2015). "Chapter 3, Section 2.2 Natural Abundance of Perchlorate on Earth". In Peter M.H. Kroneck and Martha E. Sosa...

yield. It therefore remains more efficient to obtain podophyllotoxin from natural sources. Four routes have been used to synthesize podophyllotoxin with...

Isotopically pure diamond Mole (unit) "Table of Isotopic Masses and Natural Abundances" (PDF). 1999. "Atomic Weights and the International Committee — A...

of oxygen and accounts for 99.762% of oxygen's natural abundance. The relative and absolute abundances of oxygen-16 are high because it is a principal...

is the most common isotope of uranium found in nature, with a relative abundance of 99%. Unlike uranium-235, it is non-fissile, which means it cannot sustain...

Balata M, Bellini G, Benziger J, et al. (1998). "Measurement of the 14C abundance in a low-background liquid scintillator". Physics Letters B. 422 (1–4):...

to find 13C couplings between adjacent carbon atoms. Because the natural abundance of 13C is only about 1%, only about 0.01% of molecules being studied...

plants and nuclear weapons. However, because of the low abundance of uranium-235 in natural uranium (which is, overwhelmingly, mostly uranium-238), uranium...

Purified argon gas is the most commonly used inert gas due to its high natural abundance (78.3% N2, 1% Ar in air ) and low relative cost. Unlike noble gases...

natural abundance and enrichment techniques. Natural abundance techniques can be applied without artificial disturbance. The natural 15N abundances are...

artificial production route of 125I and its short half-life, its natural abundance on Earth is effectively zero. 125I is a reactor-produced radionuclide...

processes, and atmospheric chemistry. Measuring the abundance of sulfur stable isotopes in natural materials, like bacterial cultures, minerals, or seawater...

The radioactive decay of this particular isotope explains the large abundance of argon (nearly 1%) in the Earth's atmosphere, as well as prevalence...

commercial use, e.g. in chemical synthesis, is enriched from its natural 1% abundance. Although carbon-13 can be separated from the major carbon-12 isotope...

Uranium-235 (235U or U-235) is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope uranium-238, it is fissile, i.e...

18 F is a natural trace radioisotope produced by cosmic ray spallation of atmospheric argon as well as by reaction of protons with natural oxygen: 18O...

of three major isotopes: uranium-238 (238U with 99.2739–99.2752% natural abundance), uranium-235 (235U, 0.7198–0.7202%), and uranium-234 (234U, 0.0050–0...

Oxygen-17 (17O) is a low-abundance, natural, stable isotope of oxygen (0.0373% in seawater; approximately twice as abundant as deuterium). As the only...

and high cost of lithium. An obvious advantage of sodium is its natural abundance, particularly in saltwater. Another factor is that cobalt, copper...

less) atoms per gram of the sample, at least seven times lower than the abundance measured by Hoffman et al. A 2022 study, once again using accelerator...