Atomic weights of the elements 2013 (IUPAC Technical Report)

Abstract

Abstract:The biennial review of atomic-weight determinations and other cognate data has resulted in changes for the standard atomic weights of 19 elements. The standard atomic weights of four elements have been revised based on recent determinations of isotopic abundances in natural terrestrial materials: cadmium to 112.414 (4)

Radioactive heat production of six geologically important nuclides

“…In the calculations, half‐lives and isotope masses are taken from the N ubase 2016 and A me 2016 evaluations [ Audi et al ., ; Wang et al ., ], and mean atomic masses and isotopic abundances are taken from the corresponding IUPAC 2013 reports [ Meija et al ., , ], unless otherwise stated; physical constants are from CODATA2014 [ Mohr et al ., ] (Table ). The nuclide‐specific decay data (energies and intensities) were obtained from the NuDat v.2.7 β (as retrieved in early July 2017) website (http://www.nndc.bnl.gov/nudat2) of the National Nuclear Data Center (NNDC) of the Brookhaven National Laboratory, USA, and the Recommended Data site of the Laboratoire National Henri Becquerel, Saclay, France (http://www.nucleide.org/DDEP_WG/DDEPdata.htm); in general, the newest available data were used.…”

“…Data on various atomic and nuclear properties and isotopic abundances are gathered frequently by different institutions, and every few years, international working groups release data sets of recommended values for many physical constants [ Mohr et al ., ] as well as atomic and nuclear properties [e.g., Audi et al ., ; Wang et al ., ; Meija et al ., ]. In this technical note, recent relevant data are gathered in order to calculate heat production rates for the six geologically most important heat‐producing nuclides 26 Al, 40 K, 60 Fe, 232 Th, 235 U, and 238 U, as the data frequently used in the literature are getting out of date or have not always been determined correctly or accurately.…”

“…Data on various atomic and nuclear properties and isotopic abundances are gathered frequently by different institutions, and every few years, international working groups release data sets of recommended values for many physical constants [Mohr et al, 2016] as well as atomic and nuclear properties [e.g., Audi et al, 2017;Wang et al, 2017;Meija et al, 2016a]. In this technical note, recent relevant data are gathered in order to calculate heat production rates for the six geologically most important heat-producing nuclides 26 Al, 40 K, 60 Fe, However, in b 2 ; b 1 , and (electron capture, ec) decays, a part E m of the energy is carried away by a neutrino or antineutrino, whose interaction with matter is almost nil and which therefore does not contribute to heat production or to driving chemical processes such as radiolysis; indeed, although this paper focuses on heat, the core issue really is how much of the decay energy causes any effect in matter, and so the following considerations concerning heat energy and power apply also to chemical reactions.…”

Experimental Evidence for Azeotrope Formation from Protic Ionic Liquids

“…The detailed experimental results are presented in the supporting information. The relative atomic masses used in this work were those recommended by the IUPAC Commission in 2013 …”

Defining the Potential of Nanoscale Re‐Os Isotope Systematics Using Atom Probe Microscopy

“…187 Re and 187 Os have a difference in mass of 0.000006 u (Meija et al . ), which requires a mass resolving power > 3 × 10 7 to distinguish these ionic species. These isobaric interferences are beyond the mass resolving power of any small‐scale technique currently available and require either deconvolution calculations to estimate the contribution of each isotope to the total peak, or element separation based techniques such as the Chicago Instrument of Laser Ionisation (CHILI; Stephan et al .…”