Willard Frank Libby( Chemist, Nobel Prize in Chemistry)
Comments for Willard Frank Libby
Biography Willard Frank Libby
Willard Frank Libby (17.12.1908-8.09.1980) - chemist, Nobel Prize in Chemistry.
By radiocarbon dating (based on the carbon isotope C-14) and tritium (based on hydrogen isotope) analysis.
Radiocarbon analysis used by archaeologists, geologists and other scientists to determine the dates of historical events.
Willard Frank Libby was born on December 17, 1908 in the family farm in Colorado (USA).
When Willard Libby was five years old, he (along with his parents, two brothers and two sisters) moved to a ranch near the town of Sebastopol (located in northern California, USA).
In 1926, Willard Libby graduated from high school and enrolled in the University of California at Berkeley, to become a mining engineer. But while studying Willard Frank Libby's interest in chemistry.
In 1931, Willard Libby received a bachelor's degree in chemistry and graduate studies.
Doctorate Libby was devoted to the study of radioactive nuclei with low energy.
In the late thirties of the twentieth century, Willard Frank Libby developed a method to measure very low levels of radiation.
In 1941, Libby received a Guggenheim Fellowship and took a sabbatical at the University (where he served as Adjunct Professor).
In December 1941, the U.S. entered into World War II. Willard Libby joined the nuclear physicist working on the creation of the atomic bomb.
At the very end of the war, Libby became a full professor at the University of Chicago.
As early as the end of the thirties of the twentieth century came the theory that cosmic rays penetrating the atoms in the upper atmosphere, causing the neutron flux. Neutrons are easily absorbed by atmospheric nitrogen, which then turns into a carbon-14 (a radioactive isotope of carbon, or radiocarbon, C-14).
Willard Frank Libby suggested that the radiocarbon in the air is rapidly oxidized and converted into carbon dioxide, containing atoms of carbon-14. In the process of photosynthesis, the resulting carbon dioxide is absorbed by plants through them - the other living organisms.
Caught in the organic carbon molecules remain in it. Thus in all living organisms have a constant level of radioactivity, falling gradually after death.
The half-life of carbon-14 is 5730 years.
Willard Frank Libby, has found a direct relationship between the residual radioactivity and the time since death occurring from five hundred to thirty thousand years ago (in the future - up to seventy thousand years).
To test this hypothesis, Libby made a sophisticated Geiger counter with thickened walls. Dvadtsatisantimetrovye wall of the counter absorbed terrestrial radiation, but transmits the cosmic rays.
The design Willard Libby Geiger counter continuously recorded penetrating particles. The radioactivity of the sample measured the central computer, is switched on for a few thousandths of a second. To increase the sensitivity of the instrument dating back to the radioactivity of the sample, Willard Libby put in the form of pure carbon black (later he was replaced by carbon dioxide) to the inner wall of the detector as a reference.
The accuracy of the method of Libby checked to determine the age of wood, because the lifetime of the trees easily opredeleit of the annual rings. Willard Frank Libby, has found that the results of calculations by his method and by counting the annual rings coincided.
Next Willard Frank Libby began to explore the tools found by archaeologists and is correlated with historical events, such as a piece of wood from the funerary boat of the Egyptian Pharaoh, from the Chicago Museum of Natural History.
After this method Willard Libby was used in their work, archaeologists and geologists.
During follow-up experiments revealed that the result affects latitude areas, where the samples were. Libby introduced these amendments
. Willard Frank Libby personally determined the age of a piece of charcoal from the sites of ancient people in Stonehenge, . rump of bread from Pompeii, . cob from the caves of the primitive inhabitants of New Mexico, . flap linen, . which were tied manuscripts, . found in the Middle East,
With the help of radiocarbon method has been error corrected geologists who believed that the glacial period in North America over 25 thousand years ago. In fact, this was "only" ten thousand years ago.
Poomimo carbon analysis, Willard Frank Libby is the author of the analysis of tritium (tritium - a radioactive isotope of hydrogen).
With tritium analysis was set composition of ocean waters, a plethora of other research. Using tritium analysis can even determine the age old wine.
In 1960, for the introduction of the method using carbon-14 for age determination in archeology, geology, geophysics and other fields of science "Willard Frank Libby won the Nobel Prize in Chemistry.
In the last years of his life Willard Libby was engaged in environmental issues, participated in the international program "for peaceful atom".
Second wife of Willard Libby, Leone Vude Marshall, Professor of the Environment, University of California, worked with him.
September 8, 1980 Willard Libby died.