The tungsten metallome of the hyperthermophilic archaeon Pyrococcus furiosus has been investigated using electroanalytical metal analysis and native-native 2D-PAGE with the radioactive tungsten isotope (187)W (t(1/2) = 23.9 h). P. furiosus cells have an intracellular tungsten concentration of 29 μM, of which ca. 30% appears to be free tungsten, probably in the form of tungstate or polytungstate...

In this study the use titanium and tungsten as alternatives to the noble metals in the jewellery industry was investigated. The degradation of titanium and tungsten were compared to that of gold, used as reference. Alternate immersion tests were performed in 3.5% sodium chloride and artificial perspiration. The metals’ abrasion resistance with respect to textile fabrics was determined. ...

The behavior of tungsten as plasma facing material in fusion environment is investigated using molecular dynamics simulation. Tungsten erosion and surface evolution is simulated during irradiation by carbon and deuterium ions. Non-cumulative pure carbon bombardment on crystal tungsten shows that substrate temperature does not affect carbon trapping rate, implantation depth, and tungsten sputter...

Z. Naturforsch. 50b, 315-325 (1995); received September 7, 1994 Oxadiene Complex, Molybdenum, Tungsten, X-Ray, Selective Hydrogenation Homoleptic tris(l-oxa-l,3-diene)molybdenum and tungsten complexes are formed as yel­ low, crystalline compounds in 54-80% isolated yield on treatment of the corresponding /3-unsubstituted a,/3-unsaturated ketones with W(CO)3(CH3CH2CN)3 or (y6-C6H6)Mo(CO)3 in ref...

Tungsten oxo adamantylidenes (=Ad) are a new class of readily accessible alkylidenes, that opens the possibility to evaluate broader molecular and supported olefin metathesis catalysts. In this context, W(O)(=Ad)X2, with X=pyrrolide perfluoro-tert-butoxide, were grafted on partially dehydroxylated silica, generate corresponding silica-supported tungsten adamantylidenes. The high thermal stabili...

This review aims to give a general overview of the recent use tungsten-based catalysts for wide environmental applications, with first some useful background information about tungsten oxides. Tungsten oxide materials exhibit suitable behaviors surface reactions and catalysis such as acidic properties (mainly Brønsted sites), redox adsorption (due presence oxygen vacancies) photostimulation res...

Three different types of tungsten-containing enzyme have been previously purified from Pyrococcus furiosus (optimum growth temperature, 100 degrees C): aldehyde ferredoxin oxidoreductase (AOR), formaldehyde ferredoxin oxidoreductase (FOR), and glyceraldehyde-3-phosphate oxidoreductase (GAPOR). In this study, the organism was grown in media containing added molybdenum (but not tungsten or vanadi...