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A stable isotope of carbon, having six protons and six neutrons in the nucleus. Carbon-12 makes up most naturally occurring carbon.
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Life-forms preferentially stockpile carbon-12 in their cells, so any ancient substance enriched with carbon-12 could have a biological origin.
The Company has discovered means for enhancing the energy output of fuel combustion via basically new nuclear processes such as synthesis during combustion of Carbon-12 and Oxygen 16 into Silicon-28 with the ensuing release of a large amount of heat without the emission of neutrons and without release of radioactive waste (http://www.
Isotopes are variants of the same chemical element with different atomic weights due to having different numbers of neutrons, such as the most common carbon isotope, carbon-12, and a heavier stable isotope, carbon-13.
The technique compares the amount of carbon-14 (C-14), a less common form of atmospheric carbon, to carbon-12 (C-12), which is more stable and abundant.
Carbon-14 is a heavier isotope of carbon than the 'regular' carbon-12 and, moreover, it is radioactive.
By analyzing the proportions of CO2 molecules containing the different carbon isotopes, scientists have found that the percentage of CO2 containing the Carbon-12 isotope is increasing.
Carbon-14, for example, is carbon with 14 neutrons and is an isotope of carbon-12, which has 12 neutrons.
There is a different ratio of carbon-14 and carbon-12 in steroid hormones made from plant sources compared with animal sources.
In a recent project, researchers at the University of Wyoming used the isotopic carbon-13 to carbon-12 ratio to address environmental issues associated with water co-produced with coalbed natural gas.
Most of the shells are made of one isotope of carbon, carbon-12, but the amounts of other carbon isotopes can be quite revealing.
One dalton equals one-twelfth (1/12) of the mass of a single atom of the isotope of carbon-12.
In nature, the two most abundant stable carbon isotopes are carbon-12 ([sup.