Rutherford (Rutherford), Ernest( English physicist, Nobel Prize in Chemistry, 1908)
Comments for Rutherford (Rutherford), Ernest
Biography Rutherford (Rutherford), Ernest
August 30, 1871, Mr.. - October 19, 1937
English physicist Ernest Rutherford was born in New Zealand, not far from Mr.. Nelson. He was one of 12 children wheelwright and builder, James Rutherford, a Scotsman by birth, and Martha (Thompson) Rutherford, a schoolteacher from England. First P. attended local primary and secondary schools, and then became a scholar of Nelson College, a private high school, where he showed himself a talented student, especially in mathematics. Thanks to advances in studies R. received another grant, which allowed him to go to Canterbury College in Christchurch, one of the largest cities in New Zealand.
In college at P. was greatly influenced by his teacher: taught physics and chemistry E.U. Bikerton and mathematician J. H.H. Cook. Once in 1892. R. was awarded a bachelor of arts degree, he remained at Canterbury College and continued his studies through a scholarship in mathematics. The following year he became Master of Arts, best of all passed examinations in mathematics and physics. His Master's work concerned the detection of high-frequency radio waves, whose existence was proved about ten years ago. In order to study this phenomenon, he constructed a wireless radio (for a few years before, as did Guglielmo Marconi) and use it to receive signals transmitted by colleagues from a distance of half a mile.
In 1894, Mr.. R. was awarded the degree of bachelor of science. At Canterbury College had a tradition: every student who received a Master of Arts and remaining in college, was to carry out further studies and obtain a bachelor of science. Then P. for a short time taught at a boys' school Christchurch. Thanks to its extraordinary ability in science P. was awarded a fellowship at Cambridge University in England, where he worked at the Cavendish Laboratory, one of the world's leading centers of scientific research.
Cambridge P. worked under the guidance of English physicist J. J. Thomson. At Thomson, he was impressed spent R. study of radio waves, and he in 1896. proposed to jointly study the impact of X-rays (open year earlier by Wilhelm Roentgen) in electrical discharges in gases. Their collaboration culminated in significant results, including the opening of the Thomson electron - atomic particle carrying a negative electric charge. Based on its study, Thomson and P. have suggested that, when X-rays pass through the gas, they destroy the atoms of the gas, freeing up an equal number of positively and negatively charged particles. These particles are called ions. After this work P. began studying the atomic structure.
In 1898, Mr.. R. accepted a professorship Makgillskogo University in Montreal (Canada), where he began a series of important experiments on radioactive element uranium. Soon he discovered two types of radiation: the emission of alpha rays which penetrate only a short distance, and beta-rays, which penetrate to a much greater distance. Then P. discovered that radioactive thorium emits a gaseous radioactive product, which he called "emanation" (emission. - Ed.).
Further investigation showed that two other radioactive elements - radium and actinium - also produce an emanation. Based on these and other discoveries P. came to two important for understanding the nature of radiation conclusions: all the known radioactive elements emit alpha and beta rays, . and, . more importantly, . radioactivity of any radioactive element after a certain specified period of time decreases,
. These findings gave reason to assume that all the radioactive elements belong to the family of atoms and that the basis of their classification can put a period to reduce their radioactivity.
. Based on further studies in Makgillskom University in 1901 ... 1902., P
. and his colleague Frederick Soddy outlined the main provisions established by their theory of radioactivity. In accordance with this theory radioactivity occurs when an atom rejects the particle itself, which is ejected at high velocity, and this makes the loss of one atom of a chemical element in the atom of another. Launched R. and Soddy theory in conflict with a number of pre-existing representations, including all recognized for a long time the concept that atoms are indivisible and immutable particles.
P. conducted further experiments to obtain results, which confirmed they are building a theory. In 1903, Mr.. he proved that alpha particles carry a positive charge. Because these particles have a measurable mass, 'throwing' them from the atom is crucial for the transformation of a radioactive element to another. The theory allowed P. also predict the speed with which different radioactive elements to be transformed into what he called a child material. The scientist was convinced that the alpha particles are indistinguishable from the nucleus of a helium atom. Confirmation of this was provided when Soddy, who was then working with the British chemist William Ramsay, discovered that radium emanation contains helium, estimated alpha-particle.
In 1907, Mr.. P., seeking to be closer to the center of scientific research, was appointed professor of physics at the University of Manchester (England). With Hans Geiger, who later became famous as the inventor of the Geiger counter, P. established a school in Manchester to study radioactivity.
In 1908, Mr.. R. was awarded the Nobel Prize in Chemistry 'as for its research in the collapse of elements in the chemistry of radioactive substances'. In his opening speech on behalf of the Royal Swedish Academy of Sciences K.B. Hasselberg noted the link between the work done by P., and works of Thomson, Henri Becquerel, Pierre and Marie Curie. 'The discoveries led to a tremendous conclusion: the chemical element ... able to transform into other elements', - said Hasselberg. In his Nobel lecture P. said: 'There is every reason to believe that the alpha particles, which are so freely thrown out of most radioactive substances are identical in mass and composition, and should consist of the nuclei of helium atoms. We, therefore, can not come to the conclusion that the atoms of the major radioactive elements such as uranium and thorium should be based, at least in part, from helium atoms'.
After receiving the Nobel Prize P. began studying the phenomenon was observed in the bombardment of a thin plate of gold foil by alpha particles emitted by radioactive elements such as uranium. It turned out that with the angle of reflection of alpha particles can study the structure of stable components that make up the plate. According to the accepted ideas then, . model of the atom was like a plum pudding: positive and negative charges are evenly distributed within the atom and, . hence, . could significantly change the direction of motion of alpha particles,
. P., however, noticed that some alpha particles deviated from the expected direction to a much greater extent than that allowed theory. Working with Ernest Marsden, a student at Manchester University, scientists have confirmed that a fairly large number of alpha particles deflected further than expected, some at an angle greater than 90 degrees.
Reflecting on this phenomenon, R. in 1911. proposed a new model of the atom. According to his theory, which today has become common, positively charged particles are concentrated in the center of a heavy atom and the negatively charged (electrons) are orbiting the nucleus at some distance from him. This model, like a tiny model of the solar system implies that atoms consist mostly of empty space. Widely recognized theories P. began in 1913, when the work of a scientist at Manchester University, joined the Danish physicist Niels Bohr. Bohr showed that in terms of the proposed P. structures can be explained by the well-known physical properties of the hydrogen atom, as well as a few atoms of heavier elements.
When the outbreak of World War I, P. was appointed a member of the civic committee of the Office of Inventions and Research of the British Admiralty and studied the problem of locating submarines with acoustics. After the war he returned to the Manchester laboratory and in 1919. made another fundamental discovery. Studying the structure of the hydrogen atoms with their bombardment of alpha particles, . having high speed, . he noticed on his detector signal, . which could be explained as the result of, . that the nucleus of the hydrogen atom in motion due to collision with an alpha particle,
. However, the exact same message appeared and when the scientist has replaced the hydrogen atoms of the nitrogen atoms. R. explained the reason for this phenomenon that causes decay of sustained bombardment of an atom. Ie. in a process similar to naturally occurring decay, which is caused by radiation, alpha particle knocks out a single proton (the nucleus of an atom of hydrogen) from the sustainable under normal conditions, the nucleus of an atom of nitrogen and gives it a monstrous speed. Further evidence in favor of this interpretation of this phenomenon was obtained in 1934, when Frederic Joliot and Irene Joliot-Curie discovered artificial radioactivity.
In 1919, Mr.. R. moved to Cambridge University, becoming the successor to Thompson as a professor of experimental physics and director of the Cavendish Laboratory, and in 1921 he was appointed professor of natural sciences at the Royal Institution in London. In 1930. R. was appointed chairman of a government advisory board of the Office of Scientific and Industrial Research. Being at the top of his career, a scientist attracted to work in his laboratory in Cambridge, many talented young physicists in t.ch. Rm. Blackett, John Cockcroft, James Chadwick and Ernest Walton. Despite the fact that most R. left because of this, less time for active research work, his deep interest in ongoing research and clear guidance helped to maintain a high level of work undertaken in his laboratory. Students and colleagues remembered the scientist as a dear, good man. Along with his usual foresight as a theoretician P. had a practical streak. It is thanks to her he was always accurate in explaining the observed phenomena, no matter how unusual they are at first glance may seem.
Worried about the policy pursued by the Nazi government of Adolf Hitler, R. in 1933. became president of the Academic Board of Assistance, which was created to assist those who fled from Germany.
In 1900, during a brief visit to New Zealand, P. married Mary Newton, who bore him a daughter. Almost until the end of his life he was distinguished by poor health and died in Cambridge in 1937. after a short illness. R. buried in Westminster Abbey near the tombs of Isaac Newton and Charles Darwin.
Among the obtained P. Rumford Medal Awards (1904) and Copley Medal (1922) Royal Society of London, as well as the British Order of Merit (1925). In 1931, Mr.. scientist was granted a peerage. R. was awarded honorary degrees from New Zealand, Cambridge, Wisconsin, Pennsylvania and Makgillskogo universities. He was a corresponding member of the Royal Society of Gottingen, and a member of the New Zealand Institute of Philosophy, American Philosophical Society. Academy of Sciences, St. Louis, Royal Society of London and the British Association for the Advancement of Science.