Aluminium and vanadium

In Methods 66 and 67 are described procedures for ashing polyolefin samples and ethylene propylene rubbers and the determination of aluminium and vanadium. 

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Krishnan SS, Quittkat S, Crapper DR. 1976. Atomic absorption analysis for traces of aluminium and vanadium in biological tissue. A critical evaluation of the graphite furnace atomizer. Can J Spectroscopy 21 25-30. 

Anke M, Groppel B and Krause U (1991e) The essentiality of the toxic elements aluminium and vanadium. In Momdlovic B, ed. Trace Elements in Man and Animals 7, IMI, Zagreb, Croatia, pp. 11-9-11-10. 

Not only are new materials required, covering a wider variety of different kinds of matrix, but also, as indicated above, more data are needed on some elements of interest, such as aluminium and vanadium in existing materials. A further need is for producers of biological reference materials to pay attention in future to using a more uniform style of their data (i.e. how the certified values and their uncertainties, and information values, are defined and quoted) and also to reducing the magnitude of the uncertainties to levels that would be more useful in practice. 

K. Merritt, R.W. Margevicius, and S.A. Brown, Storage and elimination of titanium, aluminium, and vanadium salts, in vivo. Journal of Biomedical Materials Research, 26, 1503-1515 (1992). 

Ear piercing A 68-year-old man developed a granulomatous dermatitis after piercing his ears. There were titanium, aluminium, and vanadium particles within macrophages... 

METHOD 66 - DETERMINATION OF ALUMINIUM AND VANADIUM CATALYST RESIDUES IN POLYALKENES AND POLYALKENE COPOLYMERS. ASHING - SPECTROPHOTOMETRIC PROCEDURE. ... 

This spectrophotometric procedure determines aluminium and vanadium catalyst residues in polyolefins and their copolymers in amounts down to 20 ppm (aluminium) and 1 ppm (vanadium). 

Determination of aluminium and vanadium catalyst residues in polyalkenes... 

Many metals occur in crude oils. Some of the more abundant are sodium, calcium, magnesium, aluminium, iron, vanadium, and nickel. They are present either as inorganic salts, such as sodium and magnesium chlorides, or in the form of organometallic compounds, such as those of nickel and vanadium (as in porphyrins). Calcium and magnesium can form salts or soaps with carboxylic acids. These compounds act as emulsifiers, and their presence is undesirable. 

Molybdenum tends to be protected by vanadium in aerated 7 1 % hydrochloric acid and it receives a high degree of protection when coupled with copper in this medium. Molybdenum corrodes somewhat faster than normal in 3 1 % nitric acid when coupled with tungsten. It is not affected by contact with titanium in 3-1% nitric acid. It is protected by aluminium and copper in aerated 10% formic acid and by aluminium in air-aerated 9% oxalic acid. In the latter solution, copper had only a slight protective effect when coupled with molybdenum. 

Calorised Coatings The nickel- and cobalt-base superalloys of gas turbine blades, which operate at high temperatures, have been protected by coatings produced by cementation. Without such protection, the presence of sulphur and vanadium from the fuel and chloride from flying over the sea promotes conditions that remove the protective oxides from these superalloys. Pack cementation with powdered aluminium produces nickel or cobalt aluminides on the surfaces of the blade aerofoils. The need for overlay coatings containing yttrium have been necessary in recent times to deal with more aggressive hot corrosion conditions. 

Dining outgassing of scrap uranium-aluminium cermet reactor cores, powerful exotherms led to melting of 9 cores. It was found that the incident was initiated by reactions at 350°C between aluminium powder and sodium diuranate, which released enough heat to initiate subsequent exothermic reduction of ammonium uranyl hexafluoride, sodium nitrate, uranium oxide and vanadium trioxide by aluminium, leading to core melting. 

The vanadium eluate was slowly evaporated under an infrared lamp, the residue dissolved in 6 M hydrochloric acid (10 ml) containing 1 ml of the aluminium chloride solution [603], and vanadium was determined by atomic absorption spectrophotometry. For calibration, suitable standard solutions were aspirated before and after each batch of samples. 

Commercial alloys composition, nomenclature. A simple and general way of identification of a commercial alloy (or of a group of similar alloys) consists of a label which gives (as rounded values) the mass% contents of the main components indicated by their chemical symbols. The alloy, for instance, Ti-6A1-4V, is a titanium-based alloy typically containing 6 mass% aluminium and 4 mass% vanadium. 

For the treatment of camotite several methods are available. The method recommended by the United States Bureau of Mines2 is as follows The ore is leached with concentrated nitric acid at 100° C., neutralised with caustic soda, and barium chloride and sulphuric acid added to the solution to precipitate the radium as barium-radium sulphate. The precipitate settles in three or four days, after which time the clear liquid is decanted into tanks and is treated with excess of boiling sodium carbonate solution in order to precipitate any iron, aluminium and chromium present. The solution now contains sodium uranyl carbonate and sodium vanadate. It is nearly neutralised with nitric acid, and caustic soda is added in sufficient quantity to precipitate the uranium as sodium uranate. After filtering, the remaining solution is neutralised with nitric acid and ferrous sulphate added, whereupon iron vanadate is thrown down. By this method it is claimed that 90 per cent, of the radium, all the uranium, and 50 per cent, of the vanadium in the camotite are recovered. 

Carbon has a great tendency to combine with vanadium to form carbides, the presence of which in the alloy renders it unsuitable for use in steel manufacture. The successful employment of carbon as the reducing agent is in fact quite recent. Formerly silicon, an iron-silicon alloy, or aluminium was used in place of carbon, but it was difficult to obtain a product which was free from silicon or aluminium, and considerable loss of vanadium took place in the slags.2... 

Aluminium-Silicon.—Vanadium possesses the property in common with a large number of other metals of forming complex alloys with aluminium and silicon.7 Several of these vanadium-aluminium-silicides, each possessing different crystalline form, have been obtained... 

Copper.—Alloys of copper and vanadium are prepared by firing a mixture of vanadium pentoxide, copper oxide, aluminium shot, lime, soda-ash, and fluorspar with the aid of sodium peroxide in a magnesia-lined crucible.2 Electrolytic methods have also been employed, and are applicable for the preparation of other vanadium alloys.3 An alloy containing 3-38 per cent, of vanadium and 96-52 per cent, of copper was found to be harder than copper and could be drawn into wire. An aluminium-copper-vanadium alloy has been prepared.4... 

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