Sentences with phrase «radioactive carbon found»

Hundreds of nuclear bomb detonations in the atmosphere prior to a 1963 test ban treaty doubled the amount of radioactive carbon found in the ocean.

Not exact matches

Researchers examined the covers with carbon dating — which looks at a radioactive form of carbon in a sample to determine its age — and other tools, finding the artifacts are authentic.

They sent soil samples for DNA testing, looking for matches with particular genes known to be found in microbes and fungi; they tried to stimulate microbial growth on a wide variety of substances and then count the cells produced; and they used highly sensitive radiorespiration activity assays, which involve feeding the soil microorganisms a food source which has been labelled with radioactive carbon, which can then be used to detect if the microorganisms are active.

Intriguingly, radioactive carbon was detected, but then another experiment found no evidence of organic compounds in the soil — there were no alien bodies.

More than 50 years later, scientists have found a way to use radioactive carbon isotopes released into the atmosphere by nuclear testing to settle a long - standing debate in neuroscience: Does the adult human brain produce new neurons?

Kim, Kawamura and colleagues find that the nebula BFS64 is associated with a molecular cloud containing 23 thousand solar masses of radioactive carbon monoxide (13CO) at a distance of 3200 pc.

Scientists have found, however, that minute levels of radioactive carbon absorbed by the barley as it grew before it was harvested to make the whisky can betray how old it is.

A radioactive isotope, carbon - 14, and part of the carbon molecule, found in unfossilized human and animal bone and charcoal, has been used to date Neamderthal remains and it was this carbon - 14 dating method that established the date for Neanderthal extinction - 28,000 years ago - as well as the dates assigned to the various Neanderthal sites found throughout Eurasia.

By using dual radioactive tracers with differing lifetimes, Wilson et al. [2017] found short term increases in CH4 and CO2 release during periods of thaw in a discontinuous permafrost were generally offset by long - term accumulation of peat in the ensuing millennia, leading the regions to continue to be net carbon sinks with negative atmospheric radiative forcing, given the long life - time of atmospheric CO2.