Francis William Aston
Francis William Aston | |
|---|---|
 | |
| Born | September 1 1877 |
| Died | November 20, 1945 (aged 68) |
| Nationality |  English |
| Alma mater | University of Birmingham University of Cambridge |
| Known for | mass spectrograph Whole Number Rule |
| Awards | File:Nobel.svg Nobel Prize for Chemistry (1922) |
| Scientific career | |
| Fields | Chemist and Physicist |
| Institutions | University of Cambridge |
| Doctoral advisor | J. J. Thomson File:Nobel.svg |
Francis William Aston (born Harborne/Birmingham, September 1 1877; died Cambridge, November 20 1945) was a British chemist and physicist who won the 1922 Nobel Prize in Chemistry "for his discovery, by means of his mass spectrograph, of isotopes, in a large number of non-radioactive elements, and for his enunciation of the whole-number rule".[1]
Biography and work
In 1893 Francis William Astonhe started his academic career at Mason College later becoming the University of Birmingham. John Henry Poynting Frankland and Tilden where teachers for chemistry and physics at this college at the time. From 1896 on he conducted additional research on organic chemistry in a private laboratory at his father’s house. In 1898 he started as a student of Frankland financed by a Forester Scholarship, his work concerned optical properties of tartaric acid compounds. He started to work on fermentation chemistry at the shool of brewing in Bermingham and was employed by W. Butler & Co. Brewery in 1900. This excursion into biochemistry ended in 1903 with his Associatship to the University of Birmingham.
After he, a trained chemist, won a scholarship to the University of Birmingham (near to his birthplace in the southwest of Birmingham) to study physics due to the discovery of X-rays and radioactivity in the mid-1890s, he started his studies of the creation of X-rays by means of the flow of current through an electronic discharge tube (a gas-filled tube with electrodes. His interest was concentrated on high vacuum. He improved the several kinds of vacuum pumps. The research conducted with self made electronic discharge tubes the Crookes dark space lead him to the discovery of a new kind of dark space in 1905 which is now known as the Aston darkspace. It he studied high vacuum discarge there that he discovered the phenomenon now known as the Aston Dark Space.[1][2][3]
After the death of his father and a trip around the world in 1908 he was appointed lecturer at the University of Birmingham in 1909, but he moved in 1910 to the Cavendish Laboratory in Cambridge on the invitation of Joseph John Thompson.
Joseph John Thompson revealed the nature of the cathode rays and the discovered the electron and he was now doing research on the positive charged "Kanalstrahlen" discovered by Eugen Goldstein in 1886. The method of deflecting particles in the "Kanalstrahlen" by magnetic fields, discovered by Wilhelm Wien in 1908, and electric fields was used to separate the different ions, by there charge and mass. The first sector field mass spectrometer was the result of these experiments. The flight path parabola of the ions were recorded on photographical plates. The electronic and magnetic properties together with the flight curve made it possible to calculate the exact mass of the ion in the mass spectrometer.
This and the speculations about isotopy directly gave rise to the modern version of the mass spectrometer capale to separate the isotopes of elements. Especially he worked on the identification of isotopes of the element neon in until 1912. He also held lectures at the Trinity College, Cambridge.
The First World War stopped the research on isotopes and mass spectroscopy and, due to his capabilities in mechanics and combustion motors, Aston joined the Royal Airforce Establishment at Farnborough as a Technical Assistant. He survived a plane crash in 1914 and started .
After the war he continued the research at the Trinity College, building, after isotopical enrichment by gass diffusion where less effective than expected, the first full functional mass spectrometer in 1919. He was able to identify the isotopes of: chlorine with 35 an 37, bromine 79 and 78, krypton with 78, 80, 82, 83, 84 and 86, giving a proof of that the natural occurring elements are comprised of a combination of isotopes. The use of electromagnetic focusing in mass spectrograph which rapidly allowed him to identify no fewer than 212 of the 287 naturally occurring isotopes. In 1921 F. W. Aston became a fellow of the famous Royal Society.
His work on isotopes also led to his formulation of the Whole Number Rule which states that "the mass of the oxygen isotope being defined, all the other isotopes have masses that are very nearly whole numbers," a rule that was used extensively in the development of nuclear energy. The exact mass of many isotopes was measured leading to the result that hydrogen has a 1% higher mass than expected by the average mass of the other elements. Aston speculated about the subatomic energy and the use of it in 1936.
As being a skilled photographer and interested in astronomy he joined several exlypse expeditions 1925 to Benkoeben, Sumatra 1932; Memphri, Canada 1936; Kamishri, Japan. He wanted also to attened the planed expeditions to South Africa in 1940 and Brazil in 1945.
Private life
In his private life he was a sports man, cross country skiing and skating in winter time, during his regular visits to Switzerland and Norway, deprived of this wintersports during First World War he started climbing. Between the age of 20 and 25 he spent a large scale of his spare time cycling. The new invention of motorized vehicles he constructed a combustion engine of his own in 1902 and participated in the Gordon Bennett Race in Ireland in 1903. Not enough with this sports he was also engaged in swimming, golf, especially with Rutherford and other colleges in Cambridge, tennis, winning some prizes at open tournaments in England Wales and Ireland and learning surfing in Honululu in 1909. Coming from a musical family he was capable to play piano, violine and cello at a level that he regularly was played in the concerts at Cambridge. He visted many places around the globe on extensive travel tours starting from 1908 when he visited and ending with a trip to Australia and New Zealand in 1938-1939.[4]
Isotopes (publ. in 1922) and Mass-spectra- and Isotopes (publ. in 1933) are his most well-known publications.
The lunar crater Aston was named in his honour.
External links
- Annotated bibliography for Francis Aston from the Alsos Digital Library for Nuclear Issues
- Aston biography from Nobel Prize site
References
- ^ Francis William Aston (1907). "Experiments on a New Cathode Dark Space in Helium and Hydrogen". Proceedings of the Royal Society of London. Series A. 80 (535): 45–49.
- ^ Francis William Aston (1907). "Experiments on the Length of the Cathode Dark Space with Varying Current Densities and Pressures in Different Gases". Proceedings of the Royal Society of London. Series. 79 (528): 80–95.
- ^ Francis William Aston (1911). "The Distribution of Electric Force in the Crookes Dark Space". Proceedings of the Royal Society of London. Series A. 84 (573): 526–535.
- ^ George de Hevesy (1948). "Francis William Aston. 1877-1945". Obituary Notices of Fellows of the Royal Society. 5 (16): 634–650.
