Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Section IV. Sample preparation techniquePerformance of catalytically condensed carbon for use in accelerator mass spectrometry
Abstract
Two catalytic processes have been explored for the preparation of suitable samples for use in 14C measurements on an accelerator mass spectrometer. A heavy hydrocarbon was condensed from C2H2 using AlBr3 as a catalyst. This process had low isotopic fractionation, and the carbon ion beam obtainable was 60–70% that from graphite. In the second process, iron powder was used to produce graphite directly from CO2 and H2 at 600 °C. A sample preparation system using this reaction has been built. The carbon product produces exceptionally intense, long-lived ion beams. The process introduces little 14C background, and has no observed memory effects.
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Before the Holocene humid period: Life-sized camel engravings and early occupations on the southern edge of the Nefud desert
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Organic carbon and planktic foraminifera radiocarbon derived Holocene sediment accumulation rates in the northern slopes of the Gulf of Mexico
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Active populations and growth of soil microorganisms are framed by mean annual precipitation in three California annual grasslands
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Also: Department of Physics, McMaster University, Hamilton, Ontario, L8S 4K1, Canada.