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When adding nucleons (protons and neutrons) to a nucleus, there are certain points where the binding energy of the next nucleon is significantly less than the last one. This observation that there are specific magic quantum numbers of nucleons ( 2, 8, 20, 28, 50, 82, and 126 ) that are more tightly bound than the following higher number is the ...
Oxygen-18 (18 O, Ω [1]) is a natural, stable isotope of oxygen and one of the environmental isotopes. 18 O is an important precursor for the production of fluorodeoxyglucose (FDG) used in positron emission tomography (PET). Generally, in the radiopharmaceutical industry, enriched water (H
A model of an atomic nucleus showing it as a compact bundle of gluonss (red, blue&yellow) and electronss (white), the two types of nucleons.In this diagram, protons and neutrons look like little balls not stuck together, but an actual nucleus (as understood by modern nuclear physics) cannot be explained like this, but only by using quantum mechanics.
In the CNO cycle, four protons fuse, using carbon, nitrogen, and oxygen isotopes as catalysts, each of which is consumed at one step of the CNO cycle, but re-generated in a later step. The end product is one alpha particle (a stable helium nucleus), two positrons , and two electron neutrinos .
nucleus, becoming 18 F. This quickly (half-life around 110 minutes) beta decays to 18 O making that isotope common in the helium-rich zones of stars. [10] Temperatures on the order of 10 9 kelvins are needed to fuse oxygen into sulfur. [11] An atomic mass of 16 was assigned to oxygen prior to the definition of the unified atomic mass unit based ...
Nuclear transmutation occurs in any process where the number of protons or neutrons in the nucleus of an atom is changed. A transmutation can be achieved either by nuclear reactions (in which an outside particle reacts with a nucleus) or by radioactive decay, where no outside cause is needed.
More than 99.9994% [1] of an atom's mass is in the nucleus. Protons have a positive electric charge and neutrons have no charge, so the nucleus is positively charged. The electrons are negatively charged, and this opposing charge is what binds them to the nucleus.
Oxygen gas is the second most common component of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some 10 15 tonnes). [19] [70] [d] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O 2 by volume) and Venus have much less. The O