Search results
Stable-isotope ratios. Measurement of the ratios of naturally occurring stable isotopes (isotope analysis) plays an important role in isotope geochemistry, but stable isotopes (mostly hydrogen, carbon, nitrogen, oxygen and sulfur) are also finding uses in ecological and biological studies.
19 sie 2011 · When the specified entities are isotopes of an element, the microscopic (atomic) quantity number ratio is the isotope-number ratio, also termed the stable isotope ratio and isotope ratio, and it is numerically equal to the macroscopic quantity isotope-amount ratio.
Magnetic sector mass spectrometer used in isotope ratio analysis, through thermal ionization. Isotope analysis is the identification of isotopic signature, abundance of certain stable isotopes of chemical elements within organic and inorganic compounds.
An isotopic signature (also isotopic fingerprint) is a ratio of non-radiogenic ' stable isotopes ', stable radiogenic isotopes, or unstable radioactive isotopes of particular elements in an investigated material. The ratios of isotopes in a sample material are measured by isotope-ratio mass spectrometry against an isotopic reference material.
Isotopic ratios expressed relative to a standard using delta notation: " = [Rsample/Rstd -1] Rsample is the isotopic ratio of a sample (e.g.,18Rsample = 18O/16Osample) Rstd is the isotopic ratio of the standard, or reference material.
15 mar 2012 · This article provides an introduction into stable isotope analysis, stable isotope terminology, and how isotope ratio measurements are quality controlled, while at the same time putting the information contained in stable isotope signatures into a forensic context.
30 kwi 2012 · We describe the basic principles of isotopic fractionation and discrimination, briefly explain the processes that govern isotopic incorporation into animal tissues, list some innovative studies, and provide cautionary notes and caveats.