Contrary to previous expectations, recent evolutionary models of zero-metallicity stars show that the development of mixing episodes at the beginning of the AGB phase allows lowand intermediate-mass stars to experience thermal pulses. If these stars, like their metal-rich counterparts, also experience partial mixing of protons from the H-rich envelope into the C-rich layers at the time of the t...

1Research Group for Terrestrial Environment, Department of Environmental Sciences, Japan Atomic Energy Research Institute, Tokai, Naka, Ibaraki 319-1195, Japan 2Division of Global Environmental Science and Engineering, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192, Japan 3Research School of Earth Sciences, The Australian National Uni...

Recent mass measurements show a substantial weakening of the binding energy difference δ2p(Z,N) = E(Z − 2, N)− 2E(Z,N) +E(Z + 2, N) in the neutron-deficient Pb isotopes. As δ2p is often attributed to the size of the proton magic gap, it might be speculated that reduction in δ2p is related to a weakening of the spherical Z = 82 shell. We demonstrate that the observed trend is described quantitat...

Events occurring within the first 10 million years of the Solar System's approximately 4.5 billion-year history, such as formation of the first solids, accretion, and differentiation of protoplanetary bodies, have determined the evolutionary course of our Solar System and the planetary bodies within it. The application of high-resolution chronometers based on short-lived radionuclides is critic...

Gamow-Teller and Fermi transitions are considered in a HF+BCS+pnQRPA theoretical framework. We show here how Gamow-Teller strength distributions can be used in a search for signatures of nuclear deformation in neutron-deficient Pb, Hg and Po isotopes, as well as how Fermi transitions allow us to quantify isospin mixing in some even Kr isotopes around N = Z. 1 Theoretical framework Microscopic m...

Transplants of the lichen Hypogymnia physodes, which is relatively tolerant to SO2 and heavy metals, were deployed for 3 months over a 60 km long SW-NE transect centered on a highly polluting Cu smelter and its adjoining town of Karabash, southern Urals, Russia. The abundance of 206Pb, 207Pb, 208Pb, and 204Pb were determined by MC-ICP-MS. The measurement of 204Pb revealed critical features, whi...

The Pb isotope ratios of 13 sediment samples, collected during Ocean Drilling Program Leg 145 at Sites 881, 883, and 884 in the North Pacific east of the Kamchatkan trench, were determined. The sediments were selected from continuously recovered cores and are representative of the range of sediment compositions recorded. The sediments analyzed are predominantly pelagic oozes, representing appro...

Sequential extraction integrated with isotope analysis was carried out on a sediment core from Liaodong Bay, northeast China, for characterizing Pb in various extraction phases and its possible sources. Results show that in all extracted fractions Pb concentrations increased abruptly in the top part of the sediments that deposited after 1980, but remained lower and rather constant before 1980. ...

There have been suggestions to measure atomic parity nonconservation (PNC) along an isotopic chain, by taking ratios of observables in order to cancel complicated atomic structure effects. Precise atomic PNC measurements could make a significant contribution to tests of the Standard Model at the level of one loop radiative corrections. However, the results also depend upon certain features of n...

A simple low-blank method is described for the analysis of Pb, Cu, and Cd in seawater using Mg(OH)(2) coprecipitation and isotope dilution inductively coupled plasma mass spectrometry (ICPMS). Here, 20-40 μL of 9 M aqueous NH(3) is mixed into a 1.3 mL seawater sample spiked with enriched isotopes of Pb, Cu, and Cd. After centrifugation, the supernatant is discarded and the Mg(OH)(2) precipitate...