Radiocarbon dating (sometimes simply known as carbon dating) is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 (C) to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" (BP), "Present" being defined as 1950. Such raw ages can be calibrated to give calendar dates. One of the most frequent uses of radiocarbon dating is to estimate the age of organic remains from archaeological sites. When plants fix atmospheric carbon dioxide (CO2) into organic material during photosynthesis they incorporate a quantity of C that approximately matches the level of this isotope in the atmosphere (a small difference occurs because of isotope fractionation, but this is corrected after laboratory analysis). After plants die or they are consumed by other organisms (for example, by humans or other animals) the C fraction of this organic material declines at a fixed exponential rate due to the radioactive decay of C. Comparing the remaining C fraction of a sample to that expected from atmospheric C allows the age of the sample to be

Publisher
Elsevier
History
1964-present
Website
http://www.sciencedirect.com/science/journal/00086223
Impact factor
4.893 (2010)

Some content from Wikipedia, licensed under CC BY-SA

Neural networks will help manufacture carbon nanotubes

Thin films made of carbon nanotubes hold a lot of promise for advanced optoelectronics, energy and medicine, however with their manufacturing process subject to close supervision and stringent standardization requirements, ...

X-ray analysis of carbon nanostructures helps material design

Nanostructures made of carbon are extremely versatile. They can absorb ions in batteries and supercapacitors, store gases and desalinate water. How well they cope with the task at hand depends largely on the structural features ...

Powder could help cut CO2 emissions

Scientists at the University of Waterloo have created a powder that can capture CO2 from factories and power plants.

Graphene takes a step toward renewable fuel

Using the energy from the sun and graphene applied to the surface of cubic silicon carbide, researchers at Linköping University, Sweden, are working to develop a method to convert water and carbon dioxide to the renewable ...

Developing environmentally friendly materials

A new research article introduces a nanofiber material produced by the electrospinning device at the Laboratory of Polymers and Textile Technology in Tallinn University of Technology, and a range of applications. The article, ...

Graphene's effects on the lungs

Graphene has been hailed as the material of the future. As yet, however, little is known about whether and how graphene affects our health if it gets into the body. A team of researchers from Empa and the Adolphe Merkle Institute ...

Engineers create most wear-resistant metal alloy in the world

If you're ever unlucky enough to have a car with metal tires, you might consider a set made from a new alloy engineered at Sandia National Laboratories. You could skid—not drive, skid—around the Earth's equator 500 times ...

page 1 from 7