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.
Isotopes are atoms of the same element (that is, with the same number of protons in their atomic nucleus), but having different numbers of neutrons. Most (66 of 94) naturally occurring elements have more than one stable isotope.Thus, for example, there are three main isotopes of carbon.f the 80 elements with at least one stable isotope, 26 have only one single stable isotope. The mean number of stable isotopes for the 80 stable elements is 3.1 stable isotopes per element. The largest number of stable isotopes that occur for a single element is 10 (for tin, element 50).