action - something that you do protective - (being) something that protects protective action - things you do, to protect yourself or other people (from something) recomâ¦mendations - someone has done some research; this is a list of what they think is good protective action recommendations - a list of things someone thinks you should do to protect ...
Stable isotope analysis gives an independent measure of fractionation such that if, for instance, a sample is 1.5% heavier in 13C than modern standard carbon through the effects of fractionation, then it will be 3% heavier in 14C than it would have been had fractionation not taken place.
Thus different isotopes of a given element all have the same number of electrons and share a similar electronic structure. Because the chemical behavior of an atom is largely determined by its electronic structure, different isotopes exhibit nearly identical chemical behavior. Isotope analysis is the determination of isotopic signature, the relative abundances of isotopes of a given element in a particular sample. 2  For biogenic substances in particular, significant variations of isotopes of C, N and O can occur.