Search results for "Uranium-234"

showing 3 items of 3 documents

(Supplement Table S2) Results of 230Th/U-dating

2016

We compared the suitability of two skeletal materials of the Atlantic brain coral Diploria strigosa for 230Th/U-dating: the commonly used bulk material comprising all skeletal elements and the denser theca wall material. Eight fossil corals of presumably Last Interglacial age from Bonaire, southern Caribbean Sea, were investigated, and several sub-samples were dated from each coral. For four corals, both the ages and the activity ratios of the bulk material and theca wall agree within uncertainty. Three corals show significantly older ages for their bulk material than for their theca wall material as well as substantially elevated 232Th content and (230Th/238U) ratios. The bulk material sam…

Hand drillUranium 238Thorium 230 Uranium 238 activity ratioThorium-230/Uranium-238 activity ratioUranium-238Thorium-230/Uranium-238 activity ratio standard deviationAGECenter for Marine Environmental Sciences MARUMMulti collector inductively coupled plasma mass spectrometer MC ICP MSCenter for Marine Environmental Sciences (MARUM)Thorium 232Thorium 232 Uranium 238 activity ratioThorium-232/Uranium-238 activity ratio standard deviationEvent labelCommentUranium 234 Uranium 238 activity ratioUranium-234/Uranium-238 activity ratioDrilling/drill rigAge 230Th/U Thorium-UraniumAge standard deviationDrilling drill rigThorium-232/Uranium-238 activity ratioUranium-234/Uranium-238 activity ratio standard deviationThorium-232230Th U Thorium UraniumEarth System ResearchGroupMulti-collector inductively coupled plasma mass spectrometer (MC-ICP-MS)standard deviation
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Uranium from German Nuclear Power Projects of the 1940s— A Nuclear Forensic Investigation

2015

Here we present a nuclear forensic study of uranium from German nuclear projects which used different geometries of metallic uranium fuel. Through measurement of the (230)Th/(234)U ratio, we could determine that the material had been produced in the period from 1940 to 1943. To determine the geographical origin of the uranium, the rare-earth-element content and the (87)Sr/(86)Sr ratio were measured. The results provide evidence that the uranium was mined in the Czech Republic. Trace amounts of (236)U and (239)Pu were detected at the level of their natural abundance, which indicates that the uranium fuel was not exposed to any major neutron fluence.

Isotopes of uraniumbusiness.industryWirtz KarlNuclear forensicsnuclear forensicsRadiochemistrychemistry.chemical_elementGeneral ChemistryActinideNuclear powerUraniumCommunicationsCatalysisuraniumUranium-236chemistryUranium-234Environmental scienceHeisenberg WernerbusinessPlutonium-239mass spectrometryAngewandte Chemie International Edition
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(Supplementary Table 1) 230Th/U results for stalagmite Cuba Grande (CG) from Pinar del Rio

2010

We present 22 U-series ages for a stalagmite from north-western Cuba based on multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and thermal ionisation mass spectrometry (TIMS). Our results reveal that the stalagmite continuously grew within the last ~1400a. Low uranium content of the sample and thus, extremely low 230Th concentrations limit the precision and accuracy of 230Th/U-dating by TIMS. Samples measured by MC-ICPMS show a high variability of 232Th content along the growth axis with some sections significantly affected by initial 230Th from a detrital phase. An a-priori bulk earth ratio for (238U/232Th) cannot be used to accurately account for this initial 230Th.…

Thorium 230 Uranium 238 ratioUranium-234 standard deviationIntegrierte Analyse zwischeneiszeitlicher Klimadynamik INTERDYNAMIKUranium 238Thorium 230 Uranium 238 activity ratioUranium-238Thorium-230/Uranium-238 activity ratio standard deviationAge commentUranium 234Integrierte Analyse zwischeneiszeitlicher Klimadynamik (INTERDYNAMIK)commentAge dateddateddated standard deviationAgeAge dated standard deviationThorium-232 standard deviationThorium-230/Uranium-238 ratioMulti collector inductively coupled plasma mass spectrometer MC ICP MSThorium-230/Thorium-232 activity ratioThorium 232Uranium-238 standard deviationSpeleothem sampleThorium 230 Thorium 232 activity ratioUranium-234/Uranium-238 activity ratioUranium 234 Uranium 238 activity ratioThorium-232DISTANCEEarth System ResearchMulti-collector inductively coupled plasma mass spectrometer (MC-ICP-MS)standard deviationThorium-230/Thorium-232 activity ratio standard deviation
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