Tungsten oxidation with

Sawateev et al. [244] have reported on tungsten oxides with regular octahedral 6- <—Cr2WOg) and with deformed... 

Oxidation of tungsten with water and reduction of tungsten oxides with hydrogen are quite similar, with the high partial pressure of water or hydrogen driving the reaction in a particular direction. The oxidation reaction has been found to follow this sequence of reactions ... 

FIGURE 8.2. The stability of various tungsten oxides with respect to the ratio of the partial pressures of H2O and H2 and inverse temperature. Increasing this ratio and inverse temperature favor more oxidation. 

The interaction of tungsten oxide with silica is weak, but is strong with titania, and intermediate with ceria and zirconia. 

Carbothermal reduction of tungsten oxides with carbon monoxide [3.47], or gas mixtures of CO/CO2, CO/H2, CH4/H2 [3.50], C2H4/H2, and C2H4/H2 [3.51], as well as by reaction between metal oxide vapor and solid carbon [3.52] have recently attracted attention for producing high surface area tungsten carbides (up to lOOm /g), for use as catalyst (see Section 10.4), and for nanophase WC/Co composite powders (see also Section 9.2.1.4) [3.53]. 

K. Friestad, G. Hagen, S. Panero, and B. Scrosati [1997] Transmission Spectra and Electrochemical Impedance Analysis of Polyaniline, Prussian Blue and Tungsten Oxide with Incorporated Nickel in Electrochromic Windows, Electrochem. Soc. Proc. 96, 353-368. 

Bersch (1901) describes Tessie du Motay s blue as prepared from 10 parts sodium tungstate, 8 parts tin crystals , 5 parts yellow prussiate and 1 part of iron(lll) chloride these are dissolved separately and mixed. The precipitate is washed and exposed to light in thin layers, with the blue colour developing over a period of a few days. According to the discoverer, the pigment consists of a compound of tungsten oxide with a double cyanide of iron and tin . 

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