Græsk: Det 41. grundstof i det periodiske system også kaldet columbium.
Niobium indgår i en række legeringer, blandt bl.a. rustfrit stål, som anvendes i atomreaktorer og i atomvåben.
Til dannelse af højere smeltepunkt for metallisk uran tilføjes uranforbindelserne: molybdæn, niobium og zirconium.
Den militære anvendelse af niobium ses bl.a. i jetflymotores halefjer.
Niobium produceres bl.a. i Australien, Brasilien, Canada, Den demokratiske republik Congo og i Nigeria.
Niobium findes hovedsageligt i malme med jern, mangan og tantal som columbite eller tantalite. I begyndelsen af december 2008 ophørte Talison Minerales minedrift på verdens største tantal mine i Wodgina, WA, pga. faldende efterspørgsel efter tantal metal. Andre kilder er malme rige på zirconum fx har Dubbo Zirconia minen (DZP) i New South Wales en af verdens mest avancerede udvvinding af zirconium, niobium, yttrium og sjældne jordarter.
Kun molybdæn og niobium er set danne faststof-løsningsmetoder med uranmetallegeringer.
USA ønskede [i 1941] undersøgelser [i Grønland] af sjældne metaller, såsom niobium, tantal og beryllium, der skulle bruges i den amerikanske krigsindustri.
Niobium is mostly found in ores with iron, manganese and tantalum as columbite or tantalite. In early December 2008 Talison Minerals suspended mining at the world’s largest tantalum operations at Wodgina, WA, because of the fall in demand for tantalum metal. Other sources are ores rich in zirconum e.g. the Dubbo Zirconia Project (DZP) in New South Wales is one of the world’s most advanced developments for zirconium, niobium, yttrium and rare earths.
Because uranium and thorium are present in many ores containing other useful minerals, the mining of these ores and the processing to recover materials such as copper, gold, niobium, coal and monazite will generally produce waste streams containing significant amounts of radioactivity.
Only molybdenum and niobium have been observed to form solid-solution alloys with uranium.
Rolled uranium-niobium parts exhibit a metastable striated structure with large variations in niobium content and hardness. Diffraction measurements at LANSCE identify the crystal phases present in homogeneous uraniumniobium alloy as the niobium content increases. Other diffraction measurements reveal that under stress, the crystal structure of uranium-niobium alloy with 6 weight-percent niobium deforms mainly by reorienting its crystalline “twins.” All these data can be used in computer models to accurately predict lifetimes and weapon performance
/ Contamination, environmental pollution
Barium ; beryllium ; cerium ; cæsium ; jod ; krypton ; lanthanum ; molybdæn ; neptunium ; plutonium ; polonium ; radioaktivitet ; ruthenium ; strontium-90 ; tellur ; tritium ; uran ; xenon ; zirkonium.
Se også: Atomfysik.


LANSCE A Key Facility for National Science and Defense. Los Alamos Science Number 30 2006.
Effects of variation of uranium enrichment on nuclear submarine reactor design. / Thomas Dominic Ippolito Jr. B.S.N.E., University of Lowell, Lowell, Massachusetts (1987). Submitted in partial fulfillment of the requirements for the degree of master of science at the Massachusetts Institute of Technology, May, 1990. Massachuaetts Institute of Technology 1990. - 257 pp.
Eske Brun og det moderne Grønlands tilblivelse 1932 – 64 / Eske Brun and the creation of modern Greenland 1932-64. / Ph.d.-afhandling af Jens Heinrich, juni 2010. - 285 s. Hovedvejleder dr. phil., lektor Thorkild Kjærgaard, Ilisimatusarfik.
Bivejleder ph.d. Søren Forchhammer. I tilknytning til Ilisimatusarfik/Grønlands Univesitet KVUG (Kommissionen for Videnskabelige Undersøgelser i Grønland).
Columbium (Niobium) and Tantalum. / Larry D. Cunningham. U.S. Geological Survey Minerals Yearbook—2000. - 15 pp.
External Radiation Exposure to the Population of the Continental U.S. from High Yield Weapons Tests Conducted by the U.S., U.K. and U.S.S.R. between 1952 and 1963: Report to the National Cancer Institute. / Harold L. Beck. 2000. - 62 s.
Root absorption of fission products by Bromus Rubens L. from the AEC Nevada test site soil contaminated by an underground nuclear explosion. / Mills, H.L.; Shields, L.M. . Radiation Botany; Journal Volume: Vol: 1: No. 1; 1961.
'By the Neubauer type of culture Bromus ruhens L. plants were grown to maturity in soil from a crater formed by an underground nuclear detonation (Blanca event) at the Nevada Test Site. Plants and soil were analyzed to determine the extent of root absorption of fission products. Of total plant radioactivity, ruthenium - rhodium-106 comprised 42.3%; strontium-yttrium-90, 46.6%, lanthanide rare earths (cerium - praseodymium-144), 10.2%, and zirconium niobium-95, 0.9%. '
Ruthenium 106, Zirconium 95, and Potassium 40 at selected ocean stations (1960-1965). / Riel, G. K. ; Pedrick, R. A. ; Attaway, D. H. ; Audet, J. J., Jr.. Naval Ordnance Lab White Oak MD, 1965. - 48 s.
'The concentrations of Potassium 40, Ruthenium-Rhodium 106, and Zirconium-Niobium 95 in the ocean have been measured by insitu gamma spectrometry at several Western North Atlantic and a few Eastern North Pacific sites between 1960 and 1965. The concentration of natural potassium 40 is proportional to salinity and close to reported average values. The zirconium-niobium 95 activity is due to fallout from nuclear weapons and decreased markedly after the test ban treaty. The ruthenium-rhodium 106 concentration reported is too high to be entirely due to nuclear tests, and shown no rational pattern with time or depth.'
Age determination of nuclear debris by the activity ratio of zirconium-95 to niobium-95. / Mamuro T, Matsuda Y. J Radiat Res (Tokyo). 1969 Sep-Dec;10(3):126-32. -
Zirconium/niobium-95 determined in Hudson River water. / Linsalata P, Cohen N.
Health Phys. 1982 Nov;43(5):742-4. -
Ratios of niobium-95 to zirconium-95 in over-ocean fallout. / Noshkin VE. Nature. 1968 Sep 21;219(5160):1241-3.
Characterization of radioactively contaminated sites for remediation purposes.
International Atomic Energy Agency, Waste Technology Section, 1998. - 107 s.
Steel and the national defense: U.S. Steel industry analysis: importance of domestically-produced steel to overall national defense objectives and economic and military security.
- Washington, DC : American Ion and Steel Institute, Specialty Steel Industry of North America, Steel Manufacturers Association, United Steelworkers, 2007. - 28 s.
'The American steel industry and the thousands of skilled men and women who comprise its workforce produce high quality, cost-competitive steel products for military use in applications ranging from aircraft carriers and nuclear submarines to Patriot and Stinger missiles, armor plate for tanks and field artillery pieces, as well as every major military aircraft in production today.'

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