Zobrazeno 1 - 10
of 17
pro vyhledávání: '"Kathryn L. Elder"'
Publikováno v:
Radiocarbon. 64:1139-1158
Late Holocene relative sea-level reconstructions are commonly generated using proxies preserved in salt-marsh and mangrove sediment. These depositional environments provide abundant material for radiocarbon dating in the form of identifiable macrofos
Publikováno v:
Radiocarbon. 64:195-199
This note describes improvements of UV oxidation method that is used to measure carbon isotopes of dissolved organic carbon (DOC) at the National Ocean Sciences Accelerator Mass Spectrometry Facility (NOSAMS). The procedural blank is reduced to 2.6
Publikováno v:
Radiocarbon. 63:321-342
Accelerator mass spectrometry (AMS) dating of pollen concentrates is often used in lake sediment records where large, terrestrial plant remains are unavailable. Ages produced from chemically concentrated pollen as well as manually picked Pinaceae gra
Autor:
Mark D. Kurz, Christopher M. Reddy, Mark L. Roberts, Ulrich M. Hanke, Ann P. McNichol, Kathryn L. Elder, Collin P. Ward, Li Xu
Publikováno v:
Radiocarbon. 63:357-374
This study describes a procedural blank assessment of the ultraviolet photochemical oxidation (UV oxidation) method that is used to measure carbon isotopes of dissolved organic carbon (DOC) at the National Ocean Sciences Accelerator Mass Spectrometry
Publikováno v:
Radiocarbon. 61:1843-1854
We present a new low-cost, high-throughput method for converting many types of organic carbon samples into graphite for radiocarbon (14C) measurements by accelerator mass spectrometry (AMS). The method combines sample combustion and reduction to grap
Autor:
William J. Jenkins, Alan R. Gagnon, Mark L. Roberts, Li Xu, Brett E. Longworth, Joshua D. Hlavenka, Kathryn L. Elder
Publikováno v:
Radiocarbon. 61:1403-1411
Replicate radiocarbon (14C) measurements of organic and inorganic control samples, with known Fraction Modern values in the range Fm = 0–1.5 and mass range 6 μg–2 mg carbon, are used to determine both the mass and radiocarbon content of the blan
Autor:
Brad E. Rosenheim, K.F. von Reden, B.X. Han, Cameron McIntyre, E Galutschek, Ann P. McNichol, William J. Jenkins, Brett E. Longworth, Kathryn L. Elder, J. R. Burton, Mark L. Roberts
Publikováno v:
Radiocarbon. 52:228-235
A new and unique radiocarbon accelerator mass spectrometry (AMS) facility has been constructed at the Woods Hole Oceanographic Institution. The defining characteristic of the new system is its large-gap optical elements that provide a larger-than-sta
Publikováno v:
Radiocarbon. 52:1182-1190
We report and compare radiocarbon observations made on 2 meridional oceanographic sections along 150°W in the South Pacific in 1991 and 2005. The distributions reflect the progressive penetration of nuclear weapons-produced 14C into the oceanic ther
Autor:
Alan R. Gagnon, K.F. von Reden, V. S. Griffin, J C. Donoghue, Patricia Long, Richard Healy, Robert J. Schneider, Kathryn L. Elder, Mark L. Roberts, D.Stuart Gerlach, Ann P. McNichol, D. Percy, Li Xu, John M. Hayes
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. :50-54
After completion of the original main program – radiocarbon analysis of over 13 000 seawater samples from the World Ocean Circulation Experiment (WOCE) – the NOSAMS Facility has entered a new phase of its operation. Major areas of concentration w
Autor:
John C. Peden, Alan R. Gagnon, Kathryn L. Elder, Walter Kutschera, Peter Steier, Michael Lerperger, Ann P. McNichol, Werner Rom
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. 172:501-512
In addition to 14C, a large set of δ13C data was produced at NOSAMS as part of the World ocean circulation experiment (WOCE). In this paper, a subset of 973 δ13C results from 63 stations in the Pacific Ocean was compared to a total number of 219 co