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Hesperium
Hesperium (or esperium; atomic symbol Es) was the name assigned to the element with atomic number 94, now known as plutonium. It was named in Italian ''Esperio'' after a Greek name of Italy, Hesperia, "the land of the West". The same team assigned the name ausenium to element 93, after Ausonia, a poetic name of Italy. By comparison, uranium, the heaviest of the primordial elements, has atomic number 92. The discovery of the element, now discredited, was claimed by Enrico Fermi and a team of scientists at the University of Rome in 1934. Following the discovery of nuclear fission in 1938, it was realized that Fermi's hesperium was a mixture of barium, krypton and other elements. The actual element was discovered several years later, and named plutonium. Fascist authorities wanted one of the elements to be named ''littorio'' after the Roman ''lictores'' who carried the ''fasces Fasces ( ; ; a ''plurale tantum'', from the Latin word ''fascis'', meaning "bundle"; it, fascio littori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Fission
Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radioactive decay. Nuclear fission of heavy elements was discovered on Monday 19 December 1938, by German chemist Otto Hahn and his assistant Fritz Strassmann in cooperation with Austrian-Swedish physicist Lise Meitner. Hahn understood that a "burst" of the atomic nuclei had occurred. Meitner explained it theoretically in January 1939 along with her nephew Otto Robert Frisch. Frisch named the process by analogy with biological fission of living cells. For heavy nuclides, it is an exothermic reaction which can release large amounts of energy both as electromagnetic radiation and as kinetic energy of the fragments (heating the bulk material where fission takes place). Like nuclear fusion, for fission to produce energy, the total binding energy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium
Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. Plutonium was first synthetically produced and isolated in late 1940 and early 1941, by a deuteron bombardment of uranium-238 in the cyclotron at the University of California, Berkeley. First, neptunium-238 ( half-life 2.1 days) was synthesized, which subsequently beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ausenium
Ausenium (atomic symbol Ao) was the name assigned to the element with atomic number 93, now known as neptunium. It was named after a Greek name of Italy, Ausonia. The same team assigned the name hesperium to element 94, after Hesperia, a poetic name of Italy. (Element 94 was later named plutonium). The discovery of the element, now discredited, was made by Enrico Fermi and a team of scientists at the University of Rome in 1934. In the same year Ida Noddack had already presented alternative explanations for the experimental results of Fermi. Following the discovery of nuclear fission in 1938, it was realized that Fermi's discovery was actually a mixture of barium, krypton, and other elements. The actual element was discovered several years later, and assigned the name neptunium. Fascist authorities wanted one of the elements to be named ''littorio'' after the Roman ''lictores'' who carried the ''fasces Fasces ( ; ; a ''plurale tantum'', from the Latin word ''fascis'', meanin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium
Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weakly radioactive because all isotopes of uranium are unstable; the half-lives of its naturally occurring isotopes range between 159,200 years and 4.5 billion years. The most common isotopes in natural uranium are uranium-238 (which has 146 neutrons and accounts for over 99% of uranium on Earth) and uranium-235 (which has 143 neutrons). Uranium has the highest atomic weight of the primordially occurring elements. Its density is about 70% higher than that of lead, and slightly lower than that of gold or tungsten. It occurs naturally in low concentrations of a few parts per million in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite. In nature, uranium is found as uranium-238 (99. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium
Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. Plutonium was first synthetically produced and isolated in late 1940 and early 1941, by a deuteron bombardment of uranium-238 in the cyclotron at the University of California, Berkeley. First, neptunium-238 ( half-life 2.1 days) was synthesized, which subsequently beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enrico Fermi
Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and the "architect of the atomic bomb". He was one of very few physicists to excel in both theoretical physics and experimental physics. Fermi was awarded the 1938 Nobel Prize in Physics for his work on induced radioactivity by neutron bombardment and for the discovery of transuranium elements. With his colleagues, Fermi filed several patents related to the use of nuclear power, all of which were taken over by the US government. He made significant contributions to the development of statistical mechanics, Quantum mechanics, quantum theory, and nuclear physics, nuclear and particle physics. Fermi's first major contribution involved the field of statistical mechanics. After Wolfgang Pauli formulated his Pauli exclusion principle, exclusion pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Fission
Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radioactive decay. Nuclear fission of heavy elements was discovered on Monday 19 December 1938, by German chemist Otto Hahn and his assistant Fritz Strassmann in cooperation with Austrian-Swedish physicist Lise Meitner. Hahn understood that a "burst" of the atomic nuclei had occurred. Meitner explained it theoretically in January 1939 along with her nephew Otto Robert Frisch. Frisch named the process by analogy with biological fission of living cells. For heavy nuclides, it is an exothermic reaction which can release large amounts of energy both as electromagnetic radiation and as kinetic energy of the fragments (heating the bulk material where fission takes place). Like nuclear fusion, for fission to produce energy, the total binding energy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lictor
A lictor (possibly from la, ligare, "to bind") was a Roman civil servant who was an attendant and bodyguard to a magistrate who held ''imperium''. Lictors are documented since the Roman Kingdom, and may have originated with the Etruscans. Origin The lictors were instituted by Rome's first king, Romulus, who appointed twelve lictors to attend him. Livy refers to two competing traditions for the reason that Romulus chose that number of lictors. The first version is that twelve was the number of birds that appeared in the augury, which had portended the kingdom to Romulus. The second version, favoured by Livy, is that the number of lictors was borrowed from the Etruscan kings, who had one lictor appointed from each of their twelve states. Eligibility Originally, lictors were chosen from the plebeians, but through most of Roman history, they seemed to have been freedmen. Centurions from the legions were also automatically eligible to become lictors on retirement from the army. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1934 Introductions
Events January–February * January 1 – The International Telecommunication Union, a specialist agency of the League of Nations, is established. * January 15 – The 8.0 1934 Nepal–Bihar earthquake, Nepal–Bihar earthquake strikes Nepal and Bihar with a maximum Mercalli intensity scale, Mercalli intensity of XI (''Extreme''), killing an estimated 6,000–10,700 people. * January 26 – A 10-year German–Polish declaration of non-aggression is signed by Nazi Germany and the Second Polish Republic. * January 30 ** In Nazi Germany, the political power of federal states such as Prussia is substantially abolished, by the "Law on the Reconstruction of the Reich" (''Gesetz über den Neuaufbau des Reiches''). ** Franklin D. Roosevelt, President of the United States, signs the Gold Reserve Act: all gold held in the Federal Reserve is to be surrendered to the United States Department of the Treasury; immediately following, the President raises the statutory gold price from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fasces
Fasces ( ; ; a ''plurale tantum'', from the Latin word ''fascis'', meaning "bundle"; it, fascio littorio) is a bound bundle of wooden rods, sometimes including an axe (occasionally two axes) with its blade emerging. The fasces is an Italian symbol that had its origin in the Etruscan civilization and was passed on to ancient Rome, where it symbolized a magistrate's power and jurisdiction. The axe originally associated with the symbol, the Labrys (Greek: , ') the double- bitted axe, originally from Crete, is one of the oldest symbols of Greek civilization. To the Romans, it was known as a ''bipennis''. The image has survived in the modern world as a representation of magisterial or collective power, law, and governance. The fasces frequently occurs as a charge in heraldry: it is present on the reverse of the U.S. Mercury dime coin and behind the podium in the United States House of Representatives; and it was the origin of the name of the National Fascist Party in Italy (from which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Symbol
Chemical symbols are the abbreviations used in chemistry for chemical elements, functional groups and chemical compounds. Element symbols for chemical elements normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised. History Earlier symbols for chemical elements stem from classical Latin and Greek vocabulary. For some elements, this is because the material was known in ancient times, while for others, the name is a more recent invention. For example, Pb is the symbol for lead (''plumbum'' in Latin); Hg is the symbol for mercury (''hydrargyrum'' in Greek); and He is the symbol for helium (a new Latin name) because helium was not known in ancient Roman times. Some symbols come from other sources, like W for tungsten (''Wolfram'' in German) which was not known in Roman times. A three-letter temporary symbol may be assigned to a newly synthesized (or not yet synthesized) element. For example, "Uno" was the temporary symbol for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krypton
Krypton (from grc, κρυπτός, translit=kryptos 'the hidden one') is a chemical element with the symbol Kr and atomic number 36. It is a colorless, odorless, tasteless noble gas that occurs in trace amounts in the atmosphere and is often used with other rare gases in fluorescent lamps. With rare exceptions, krypton is chemically inert. Krypton, like the other noble gases, is used in lighting and photography. Krypton light has many spectral lines, and krypton plasma is useful in bright, high-powered gas lasers (krypton ion and excimer lasers), each of which resonates and amplifies a single spectral line. Krypton fluoride also makes a useful laser medium. From 1960 to 1983, the official definition of meter was based on the wavelength of one spectral line of krypton-86, because of the high power and relative ease of operation of krypton discharge tubes. History Krypton was discovered in Britain in 1898 by William Ramsay, a Scottish chemist, and Morris Travers, an Engli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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