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  • THORIUM
  • A small team of researchers from the University of California, Lawrence Berkeley National Laboratory and LPCNO, Université de Toulouse, has developed a way to synthesize a thorium-aluminum complex with an actinide element to donate electrons when bonding with a metal. (phys.org)
  • The approach introduced by Gruen was fruitful not only in helping to provide a fundamental understanding of fused salt chemistry, but also in its implications for the eventual development of a homogeneous thermal breeder reactor based on fused salt solutions containing the relatively plentiful element thorium. (wikipedia.org)
  • oxidation state
  • In relation to the oxide or halide, for a given oxidation state of an element A, if two halogen atoms replace one oxygen atom, or vice versa, the overall charge on the molecule is unchanged and the coordination number of the central atom decreases by one. (wikipedia.org)
  • ligand field
  • After a brief apprenticeship in applying standard versions of ligand field modelling to transition metal complexes, tackling single-crystal polarized spectra and magnetic anisotropy of Ni(II) and Co(II) complexes in the less usual five-coordination states, Werner Urland conceived his own "trademark" devising a ligand-field potential for f electrons in the frame of Angular Overlap Model. (wikipedia.org)
  • IUPAC
  • In 1994 a committee of IUPAC recommended that element 108 be named hahnium (Hn) after the German physicist Otto Hahn, after an older suggestion of ottohahnium (Oh) in spite of the long-standing convention to give the discoverer the right to suggest a name, so that elements named after Hahn and Lise Meitner (meitnerium) would be next to each other, honoring their joint discovery of nuclear fission. (wikipedia.org)
  • The IUPAC/IUPAP Joint Working Party (JWP) recognised the GSI team as discoverers in their 2001 report, giving them the right to suggest a name for the element. (wikipedia.org)
  • In 1994 a committee of IUPAC recommended that element 107 be named bohrium, not nielsbohrium, since there was no precedence for using a scientist's complete name in the naming of an element. (wikipedia.org)
  • The priority of the discovery and therefore the naming of the element was disputed between Soviet and American scientists, and it was not until 1997 that International Union of Pure and Applied Chemistry (IUPAC) established seaborgium as the official name for the element. (wikipedia.org)
  • The priority of the discovery and therefore the naming of the element was disputed between Soviet and American scientists, and it was not until 1997 that International Union of Pure and Applied Chemistry (IUPAC) established rutherfordium as the official name for the element. (wikipedia.org)
  • In 1992, the IUPAC/IUPAP Transfermium Working Group (TWG) assessed the claims of discovery and concluded that both teams provided contemporaneous evidence to the synthesis of element 104 and that credit should be shared between the two groups. (wikipedia.org)
  • The International Union of Pure and Applied Chemistry (IUPAC) adopted unnilquadium (Unq) as a temporary, systematic element name, derived from the Latin names for digits 1, 0, and 4. (wikipedia.org)
  • In 1994, IUPAC suggested the name dubnium (Db) to be used since rutherfordium was suggested for element 106 and IUPAC felt that the Dubna team should be rightly recognized for their contributions. (wikipedia.org)
  • Chemistry
  • Dr. Seaborg shared the 1951 Nobel Prize in chemistry for his work with the new elements. (wikipedia.org)
  • The chemical properties of hassium are characterized only partly, but they compare well with the chemistry of the other group 8 elements. (wikipedia.org)
  • The chemical properties of seaborgium are characterized only partly, but they compare well with the chemistry of the other group 6 elements. (wikipedia.org)
  • They compare well with the chemistry of the other group 4 elements, even though some calculations had indicated that the element might show significantly different properties due to relativistic effects. (wikipedia.org)
  • In the 1950s, most inorganic chemistry textbooks defined transition elements as finishing at group 10 (nickel, palladium and platinum), therefore excluding group 11 (copper, silver and gold), and group 12 (zinc, cadmium and mercury). (wikipedia.org)
  • Minor actinides - Actinides found in significant quantities in nuclear fuel, other than U and Pu: Np, Am, Cm. Heavy atom - term used in computational chemistry to refer to any element other than hydrogen and helium. (wikipedia.org)
  • given to element 105
  • The Soviet scientists at the Joint Institute for Nuclear Research in Dubna, Russia had suggested this name be given to element 105 (which was finally called dubnium) and the German team wished to recognise both Bohr and the fact that the Dubna team had been the first to propose the cold fusion reaction to solve the controversial problem of the naming of element 105. (wikipedia.org)
  • The name dubnium was given to element 105 at the same time. (wikipedia.org)
  • synthetic
  • 249 98Cf + 18 8O → 263m 106Sg + 4 1 0n → 259 104Rf + α → 255 102No + α A dispute thus arose from the initial competing claims of discovery, though unlike the case of the synthetic elements up to element 105, neither team of discoverers chose to announce proposed names for the new elements, thus averting an element naming controversy temporarily. (wikipedia.org)
  • isotope
  • the latter one was described as having been caused by an isotope of element 105. (wikipedia.org)
  • These have yielded isotope ratios of heavy elements in presolar SiC grains found in meteorites, data that are important for an understanding of the origin of the presolar nebula from which the sun condensed five billion years ago. (wikipedia.org)
  • Periods
  • The standard form of the table consists of a grid of elements with rows called periods and columns called groups The history of the periodic table reflects over a century of growth in the understanding of chemical properties. (wikipedia.org)
  • isotopes
  • The synthesis of element 108 was first attempted in 1978 by a Russian research team led by Yuri Oganessian and Vladimir Utyonkov at the Joint Institute for Nuclear Research (JINR) in Dubna, using reactions that would generate the isotopes hassium-270 and hassium-264. (wikipedia.org)
  • the research was aimed at looking for fission fragments of isotopes of element 105. (wikipedia.org)
  • After having ruled out nucleon transfer reactions as a cause for these activities, the team concluded that the most likely cause of the activities was the spontaneous fission of isotopes of element 106. (wikipedia.org)
  • Dubna
  • This statement came in spite of the combined data also supporting the Russian 1983 discovery claim and the TWG also acknowledging that "very probably element 108 played a role in the Dubna experiment. (wikipedia.org)
  • The element was officially named dubnium in 1997 after the town of Dubna, the site of the JINR. (wikipedia.org)
  • The first report of discovery of element 105 came from the Joint Institute for Nuclear Research (JINR) in Dubna, Moscow Oblast, Russian SFSR, Soviet Union, in 1968. (wikipedia.org)
  • The Dubna team agreed with the German group's naming proposal for element 107. (wikipedia.org)
  • Evidence of element 106 was first reported in 1974 by a Russian research team in Dubna led by Yuri Oganessian, in which targets of lead-208 and lead-207 were bombarded with accelerated ions of chromium-54. (wikipedia.org)
  • magnetic
  • The compound shows a metamagnetic transition (MT) from paramagnetic to ferromagnetic states at low temperature (T) when an external magnetic field (H) is applied. (go.jp)
  • In principle, XMCD is an element- and electronic-orbital-specific magnetic probe. (go.jp)
  • Gruen contributed seminal studies that led to a detailed elucidation of the 5f electronic structure of several of these elements, using low-temperature magnetic susceptibility and fluorescence spectroscopic techniques. (wikipedia.org)
  • respectively
  • Depending on where these adjacent groups are judged to begin and end, there are at least five competing proposals for which elements to include: the three most common contain six, ten and thirteen elements, respectively (see image). (wikipedia.org)
  • carbon
  • For highly electropositive elements, such as lithium and sodium, the carbon ligand exhibits carbanionic character, but free carbon-based anions are extremely rare, an example being cyanide. (wikipedia.org)
  • found
  • Only hydrogen is found free in nature as a pure element, and that is as diatomic hydrogen gas. (thoughtco.com)
  • It is a metallic element found in many minerals of the Earth's crust. (chem4kids.com)
  • Technetium is an element that is not found in nature. (chem4kids.com)
  • A number of physical elements (such as platinum, tin and zinc) have been known from antiquity, as they are found in their native form and are relatively simple to mine with primitive tools. (wikipedia.org)
  • In 1829, he found that he could form some of the elements into groups of three, with the members of each group having related properties. (wikipedia.org)
  • Amongst this diversity, scientists have found it useful to use names for various sets of elements, that illustrate similar properties, or their trends of properties. (wikipedia.org)
  • name kurchatovium
  • The Russian scientists proposed the name kurchatovium and the American scientists suggested the name rutherfordium for the new element. (wikipedia.org)
  • Since the Soviets claimed to have first detected the new element they suggested the name kurchatovium (Ku) in honor of Igor Kurchatov (1903-1960), former head of Soviet nuclear research. (wikipedia.org)
  • discoverer
  • Debierne, who is now considered by the vast majority of historians as the discoverer, lost interest in the element and left the topic. (wikipedia.org)
  • 1997
  • The American team in 1997 proposed the name hahnium after Otto Hahn (previously this name had been used for element 105). (wikipedia.org)
  • chemical
  • A limiting reactant is the limiting factor or element in a chemical reaction. (chem4kids.com)
  • The safe management of fission energy depends in large part on a knowledge of the chemical properties of the actinide elements, many of which are man-made. (wikipedia.org)
  • After a comparison of the substances half-lives determined by Debierne, Harriet Brooks in 1904, and Otto Hahn and Otto Sackur in 1905, Debierne's chosen name for the new element was retained because it had seniority, despite the contradicting chemical properties he claimed for the element at different times. (wikipedia.org)
  • The history of the periodic table is also a history of the discovery of the chemical elements. (wikipedia.org)
  • There are currently 118 known chemical elements exhibiting a large number of different physical and chemical properties. (wikipedia.org)