Isotopic Abundances and Atomic Weights: IUPAC Commission II.1 Today

Letter to the Editor: New IUPAC guidelines for the reporting of stable hydrogen, carbon, and oxygen isotope-ratio data

On behalf of the International Union of Pure and Applied Chemistry (IUPAC), and in particular its Commission on Atomic Weights and Isotopic Abundances, I should like to inform the readers of the Journal of Research of the National Institute of Standards and Technology of the following, based on Refs. [1] and [2]. To eliminate possible confusion in the reporting of isotopic abundances on noncorr...

Guidelines and recommended terms for expression of stable-isotope-ratio and gas-ratio measurement results.

To minimize confusion in the expression of measurement results of stable isotope and gas-ratio measurements, recommendations based on publications of the Commission on Isotopic Abundances and Atomic Weights of the International Union of Pure and Applied Chemistry (IUPAC) are presented. Whenever feasible, entries are consistent with the Système International d'Unités, the SI (known in English as...

IUPAC-IUB Commission on Biochemical Nomenclature. Tentative rules.

Interstellar Atomic Abundances

A broad array of interstellar absorption features that appear in the ultraviolet spectra of bright sources allows us to measure the abundances and ionization states of many important heavy elements that exist as free atoms in the interstellar medium. By comparing these abundances with reference values in the Sun, we find that some elements have abundances relative to hydrogen that are approxima...

The Separation of Chlorine into Isotopes (Isotopic Elements) and the Whole Number Rule for Atomic Weights.

The purpose of this note is to outline a theory elaborated by the author Which appears to afford satisfactory explanation of much of the published data relating to the degradation of carbohydrates by enzyme systems both "in vivo" and "in vitro." Experimental work to test the theory has been in progress for some time' and on completion may necessitate certain modifications. As this is intended t...