Radiocarbon measurements, carbon

Bischoff JL, Fitzpatrick JA (1991) U-series dating of impure carbonates An isochron technique using total-sample dissolution. Geochim Cosmochim Acta 55 543-554 Broecker WS, Olson EA, Orr PC (1960) Radiocarbon measurements and annual rings in cave formations. Nature 185 93-94... 

All of the above particulate investigations were based on mini-radiocarbon measurement techniques, with sample masses typically in the range of 5-10 mg-carbon. This constituted a major advantage, because it was practicable to select special samples (given region, source impact, sediment depth) and to further subject such samples to physical (size) or chemical separation before 14C measurement. This type of "serial selectivity" provides maximum information content about the samples and in fact it is essential when information is sought for the sources or atmospheric distributions of pure chemical species, such as methane or elemental carbon. 

Tp " JMgMe, 42 316 [Tp JZnOH complexes, 42 354-359 use in radiocarbon measurement, 3 303 Carbon disulfide complexes, osmium, 37 239 insertion reactions... 

An alternative to the above described approaches is the radiocarbon method that allows a distinction of contemporary carbon (from biogenic emissions and combustion of biomass) and carbon from combustion of fossil fuels in particulate carbonaceous matter [15, 41,42]. In contrast to fossil fuels where the 14C isotope is completely depleted, CM emitted from WB shows a contemporary radiocarbon level. Radiocarbon measurements are often combined with measurements of complementary source specific tracers (macro-tracer) for additional information of source impacts [14, 43, 44]. 

Appendix 2. Modeling Carbon Dynamics Using Radiocarbon Measurements 256... 

APPENDIX 2. MODELING CARBON DYNAMICS USING RADIOCARBON MEASUREMENTS... 

Trumbore, S. E. (1993). Comparison of carbon dynamics in tropical and temperate soils using radiocarbon measurements. Global Biogeochem. Cycles 7(2), 275-290. 

Masiello, C. A., Druffel, E. R. M., and Currie, L. A. (2002). Radiocarbon measurements of black carbon in aerosols and ocean sediments. Geochim. Cosmochim. Acta 66, 1025-1036. 

Calibration of Radiocarbon Measurement To Yield the Calendar Age. It was previously thought that if the half-life of 14C was accurately known, then a simple exponential decay equation could be applied to learn the age of archaeological organic materials. The measurement would be subject only to errors in measurement of the ratio of the radiocarbon in the sample, A, to the equivalent quantity in modern carbon, A0. However, it is now known that A0 has been far from constant in the past few thousand... 

Table II. Sunnyvale Skeleton Radiocarbon Measurements by Carbon Dioxide Gas Proportional Decay Counting and...

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