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
Physicists from the Moscow Institute of Physics and Technology and the Institute for High Pressure Physics of the Russian Academy of Sciences have used computer modeling to refine the melting curve of graphite that has been ...
Nanomaterials
Jan 06, 2020
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205
The world of aerospace increasingly relies on carbon fiber reinforced polymer composites to build the structures of satellites, rockets and jet aircraft.
Nanophysics
Nov 13, 2019
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Carbon nanotubes (CNTs) are valuable for a wide variety of applications. Made of graphene sheets rolled into tubes 10,000 times smaller than a human hair, CNTs have an exceptional strength-to-mass ratio and excellent thermal ...
Nanomaterials
Nov 12, 2019
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481
Biologically inspired engineering to produce biomimetic materials and scaffolds typically occurs at the micro- or nanoscale. In a new study on Science Advances, Iaroslav Petrenko and a multidisciplinary global research team, ...
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, ...
Nanomaterials
Aug 08, 2019
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Researchers have developed a revolutionary method to intricately grow and protect some of the world's most exciting nanomaterials—graphene and carbon nanotubes (CNT).
Nanomaterials
May 09, 2019
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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 ...
Nanomaterials
Mar 14, 2019
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29
Scientists at the University of Waterloo have created a powder that can capture CO2 from factories and power plants.
Environment
Dec 19, 2018
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Brown University researchers have shown a way to use graphene oxide (GO) to add some backbone to hydrogel materials made from alginate, a natural material derived from seaweed that's currently used in a variety of biomedical ...
Nanomaterials
Nov 21, 2018
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152
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 ...
Nanomaterials
Nov 08, 2018
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