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Niobium-1% zirconium is used in rocketry and in the nuclear industry. It is regarded as a low-strength alloy. [1] [2]C-103, which is 89% Nb, 10% Hf and 1% Ti, is used for the rocket nozzle of the Apollo service module and the Merlin vacuum [3] engines; it is regarded as a medium-strength alloy.
Within this range, only 96 Nb, 101 Nb, and 103 Nb do not have isomers. The most stable of niobium's isomers is 93m Nb with half-life 16.13 years. The least stable isomer is 84m Nb with a half-life of 103 ns. All of niobium's isomers decay by isomeric transition or beta decay except 92m1 Nb, which has a minor electron capture branch. [44]
Naturally occurring niobium (41 Nb) is composed of one stable isotope (93 Nb). The most stable radioisotope is 92 Nb with a half-life of 34.7 million years. The next longest-lived niobium isotopes are 94 Nb (half-life: 20,300 years) and 91 Nb with a half-life of 680 years. There is also a meta state of 93 Nb at 31 keV whose half-life is 16.13 ...
The main source of niobium until now has been from the ore mineral columbite that is extracted widely in Canada, Brazil, Australia and Nigeria, with China obtaining nearly 95 per cent of the ...
Organoniobium chemistry is the chemistry of compounds containing niobium-carbon (Nb-C) bonds. Compared to the other group 5 transition metal organometallics, the chemistry of organoniobium compounds most closely resembles that of organotantalum compounds.
Ferroniobium is an important iron-niobium alloy, with a niobium content of 60-70%. [1] It is the main source for niobium alloying of HSLA steel and covers more than 80% of the worldwide niobium production. The niobium is mined from pyrochlore deposits and is subsequently transformed into the niobium pentoxide Nb 2 O 5.
After the separation from the other minerals, the mixed oxides of tantalum Ta 2 O 5 and niobium Nb 2 O 5 are obtained. To produce niobium, the first step in the processing is the reaction of the oxides with hydrofluoric acid: [55] Ta 2 O 5 + 14 HF → 2 H 2 [TaF 7] + 5 H 2 O Nb 2 O 5 + 10 HF → 2 H 2 [NbOF 5] + 3 H 2 O
Niobium(III) chloride forms a series of compounds with the formula Nb 2 Cl 6 L x with Nb=Nb double bond. With tertiary phosphines and arsines, the complexes are edge-share bioctahedra, e.g., Nb 2 Cl 6 (PPhMe 2) 4. [7] Thioethers form adducts with one bridging thioether (R 2 S). These face-sharing bioctahedra have the formula Nb 2 X 6 (R 2 S) 3 ...