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Niton (element)
Radon is a chemical element; it has symbol Rn and atomic number 86. It is a radioactive noble gas and is colorless and odorless. Of the three naturally occurring radon isotopes, only Rn has a sufficiently long half-life (3.825 days) for it to be released from the soil and rock where it is generated. Radon isotopes are the immediate decay products of radium isotopes. The instability of Rn, its most stable isotope, makes radon one of the rarest elements. Radon will be present on Earth for several billion more years despite its short half-life, because it is constantly being produced as a step in the decay chains of U and Th, both of which are abundant radioactive nuclides with half-lives of at least several billion years. The decay of radon produces many other short-lived nuclides, known as "radon daughters", ending at stable isotopes of lead. Rn occurs in significant quantities as a step in the normal radioactive decay chain of U, also known as the uranium series, which slowly de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Element
A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its atomic nucleus, nucleus. Atoms of the same element can have different numbers of neutrons in their nuclei, known as isotopes of the element. Two or more atoms can combine to form molecules. Some elements form Homonuclear molecule, molecules of atoms of said element only: e.g. atoms of hydrogen (H) form Diatomic molecule, diatomic molecules (H). Chemical compounds are substances made of atoms of different elements; they can have molecular or non-molecular structure. Mixtures are materials containing different chemical substances; that means (in case of molecular substances) that they contain different types of molecules. Atoms of one element can be transformed into atoms of a different element in nuclear reactions, which change an atom's at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium Series
In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather into another radioisotope. The isotope produced by this radioactive emission then decays into another, often radioactive isotope. This chain of decays always terminates in a stable isotope, whose nucleus no longer has the surplus of energy necessary to produce another emission of radiation. Such stable isotopes may be said to have reached their '' ground states''. The stages or steps in a decay chain are referred to by their relationship to previous or subsequent stages. Hence, a ''parent isotope'' is one that undergoes decay to form a ''daughter isotope''. For example element 92, uranium, has an isotope with 144 neutrons ( 236U) and it decays into an isotope of element 90, thorium, with 142 neutrons ( 232Th). The daughter isotope may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Whytlaw-Gray
Robert H. Whytlaw-Gray, OBE, FRS (14 June 1877 – 29 January 1958) was an English chemist, born in London. He studied at the University of Glasgow and University College London and was Professor of Inorganic Chemistry at the University of Leeds. He and William Ramsay isolated radon and studied its physical properties (density, weight).[] Early life and education Robert Whytlaw-Gray (also Robert Whytlaw Whytlaw-Gray) was born in Hampstead on 14 June 1877, son of Robert James Gray and Mary Gilkieson Gemmell Whytlaw. His early education was at St Paul’s School, where little science was taught. When he was about 12, Whytlaw-Gray set up a laboratory at home and taught himself chemistry. At eighteen he went to the University of Glasgow to study engineering and it was there that he heard a lecture by William Ramsay which so inspired him that he determined to go to University College London (UCL), to study under him. This he did, from 1896, so successfully that he won the Tufnell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Ramsay
Sir William Ramsay (; 2 October 1852 – 23 July 1916) was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" along with his collaborator, John William Strutt, 3rd Baron Rayleigh, who received the Nobel Prize in Physics that same year for their discovery of argon. After the two men identified argon, Ramsay investigated other atmospheric gases. His work in isolating argon, helium, neon, krypton, and xenon led to the development of a new section of the periodic table. Early years Ramsay was born at 2 Clifton StreetGlasgow Post Office Directory 1852 in Glasgow on 2 October 1852, the son of civil engineer and surveyor, William C. Ramsay, and his wife, Catherine Robertson. The family lived at 2 Clifton Street in the city centre, a three-storey and basement Georgian townhouse. The family moved to 1 Oakvale Place in the Hillhead district in his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
André-Louis Debierne
André-Louis Debierne (; 14 July 1874 – 31 August 1949) was a French chemist. He is often considered the discoverer of the element actinium, though H. W. Kirby disputed this in 1971 and gave credit instead to German chemist Friedrich Oskar Giesel. Biography Debierne studied at the elite École supérieure de physique et de chimie industrielles de la ville de Paris (ESPCI ParisTech). He was a student of Charles Friedel, was a close friend of Pierre and Marie Curie and was associated with their work. In 1899, he discovered the radioactive element actinium, as a result of continuing the work with pitchblende Uraninite, also known as pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the urani ... that the Curies had initiated. After the death of Pierre Curie in 1906, Debierne helped Marie Curie carry on and worked ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Ernst Dorn
Friedrich Ernst Dorn (27 July 1848 – 16 December 1916) was a German physicist. He is best remembered for his discovery that radium emits a radioactive substance, later named radon. Life and work Dorn was born in Guttstadt (Dobre Miasto), Province of Prussia (nowadays Warmia in Poland), and died in Halle, Province of Saxony. He was educated at Königsberg and went on to teach at the university level. In 1885, at Halle University, Dorn took over the position of personal ''ordinarius'' professor for theoretical physics from Anton Oberbeck. Since Dorn was already an ''ordinarius'' professor, he was allowed to assume the title so as to not appear as having been demoted. In 1895, Dorn succeeded Hermann Knoblauch at Halle as the ''ordinarius'' professor for experimental physics and director of the physics institute. Dorn's previous duties were assumed by Carl Schmidt, who had been a Privatdozent and was called as an ''extraordinarius'' professor for theoretical physics. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorium Oxide
Thorium oxide may refer to: * Thorium monoxide (thorium(II) oxide), ThO * Thorium dioxide Thorium dioxide (ThO2), also called thorium(IV) oxide, is a crystalline solid, often white or yellow in colour. Also known as thoria, it is mainly a by-product of lanthanide and uranium production. Thorianite is the name of the mineralogical for ... (thorium(IV) oxide), ThO2 {{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montreal
Montreal is the List of towns in Quebec, largest city in the Provinces and territories of Canada, province of Quebec, the List of the largest municipalities in Canada by population, second-largest in Canada, and the List of North American cities by population, ninth-largest in North America. It was founded in 1642 as ''Fort Ville-Marie, Ville-Marie'', or "City of Mary", and is now named after Mount Royal, the triple-peaked mountain around which the early settlement was built. The city is centred on the Island of Montreal and a few, much smaller, peripheral islands, the largest of which is Île Bizard. The city is east of the national capital, Ottawa, and southwest of the provincial capital, Quebec City. the city had a population of 1,762,949, and a Census geographic units of Canada#Census metropolitan areas, metropolitan population of 4,291,732, making it the List of census metropolitan areas and agglomerations in Canada, second-largest metropolitan area in Canada. French l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
McGill University
McGill University (French: Université McGill) is an English-language public research university in Montreal, Quebec, Canada. Founded in 1821 by royal charter,Frost, Stanley Brice. ''McGill University, Vol. I. For the Advancement of Learning, 1801–1895.'' McGill-Queen's University Press, 1980. the university bears the name of James McGill, a Scottish merchant, whose bequest in 1813 established the University of McGill College. In 1885, the name of the university was officially changed to McGill University. Its main campus is on the slope of Mount Royal in downtown Montreal in the borough of Ville-Marie, with a second campus situated in Sainte-Anne-de-Bellevue, west of the main campus on Montreal Island. The university is one of two members of the Association of American Universities located outside the United States, alongside the University of Toronto, and is the only Canadian member of the Global University Leaders Forum (GULF) within the World Economic Forum. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Bowie Owens
Robert Bowie Owens (October 29, 1870 – November 3, 1940) was a U.S. electrical engineer. He was the director of the Maryland Academy of Science. He was secretary of Franklin Institute from 1910 to 1924. He is credited as a discoverer of the alpha ray. Biography He was born October 29, 1870. Owens was a graduate of the Industrial College of Johns Hopkins University and Columbia University. On August 19, 1891 he was employed as an adjunct professor in electrical engineering in the newly formed school of Electrical Engineering at the University of Nebraska. After seven years of service he left the now-department in shape comparable to other universities of the time, in August 1898, Owens took a position as MacDonald Chair of Electrical Engineering at McGill University in Montreal. During his time at Nebraska, Owens was involved in forming ''The Society of Electrical Engineers of the University of Nebraska'' in 1893, the body which is known today as the IEEE. Owens served a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson (30 August 1871 – 19 October 1937) was a New Zealand physicist who was a pioneering researcher in both Atomic physics, atomic and nuclear physics. He has been described as "the father of nuclear physics", and "the greatest experimental physics, experimentalist since Michael Faraday". In 1908, he was awarded the Nobel Prize in Chemistry "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances." He was the first Oceanian Nobel laureate, and the first to perform the awarded work in Canada. Rutherford's discoveries include the concept of radioactive half-life, the radioactive element radon, and the differentiation and naming of Alpha decay, alpha and Beta particle, beta radiation. Together with Thomas Royds, Rutherford is credited with proving that alpha radiation is composed of helium nuclei. In 1911, he theorized that atoms have their charge concentrated in a very small atomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead-208
Lead (82Pb) has four observationally stable isotopes: 204Pb, 206Pb, 207Pb, 208Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide. The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series, terminates with the thallium isotope 205Tl. The three series terminating in lead represent the decay chain products of long-lived primordial 238U, 235U, and 232Th. Each isotope also occurs, to some extent, as primordial isotopes that were made in supernovae, rather than radiogenically as daughter products. The fixed ratio of lead-204 to the primordial amounts of the other lead isotopes may be used as the baseline to estimate the extra amounts of radiogenic lead present in rocks as a result of decay from uranium and thorium. (See lead–lead dating and uranium–lead dating.) The long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
