Gallium phase

The two metals were mutually saturated by gentle rocking in a thermostat for at least 24hours before use. The saturated phases were used for all measurements. (The mercury phase contains about 1.3% gallium, and the gallium phase about 5.8% mercury at 25°C. [2,15].)... 

The lower figure applied to glass previously exposed to the mercury phase, and the higher, to glass previously exposed to the gallium phase.)... 

Figure 21 Raman chemical imaging of sintered MOX surrogate pellet (A) Raman image of 292 cm highlighting distribution of a gallium phase (B) Raman image at 464 cm indicating cerium oxide distribution (C) normalized LCTF spectra from regions of interest, indicated on the Raman image.

JR Schoonover, A Saab, JS Bridgewater, GJ Havrilla, CT Zugates, PJ Treado. Raman/SEM chemical imaging of a residual gallium phase in a mixed oxide feed surrogate. Appl Spectrosc 54 (in press). 

Thermodynamic parameters determined for gallium phases and hydrolysis species are listed in Table 13.17. The data have been calculated using the thermodynamic data for Ga that were determined from the data given by Benezeth et al. (1997) and that for water given in Chapter 5. 

There is quite good agreement between the thermodynamic parameters for the gallium phases and hydrolysis species derived in the present work with those available in the literature (Benezeth et al., 1997 Diakonov et al., 1997). Two of the literature entropy values sit marginally outside the uncertainty range of the values derived in the present review as does one of the enthalpy of formation values. 

Gallium (I). Hahdes of Ga(I) ate known only in the vapor phase. Coordination complexes of GaCl and GaBt have been obtained with dioxane, morpholine, and acetylacetone. 

In an alternative industrial process, resorcinol [108-46-3] is autoclaved with ammonia for 2—6 h at 200—230°C under a pressurized nitrogen atmosphere, 2.2—3.5 MPa (22—35 atm). Diammonium phosphate, ammonium molybdate, ammonium sulfite, or arsenic pentoxide maybe used as a catalyst to give yields of 60—94% with 85—90% selectivity for 3-aminophenol (67,68). A vapor-phase system operating at 320°C using a siUcon dioxide catalyst impregnated with gallium sesquioxide gives a 26—31% conversion of resorcinol with a 96—99% selectivity for 3-aminophenol (69). 

Hydrolysis. 1,1,1-Trichloroethane heated with water at 75—160°C under pressure and in the presence of sulfuric acid or a metal chloride catalyst decomposes to acetyl chloride, acetic acid, or acetic anhydride (54). However, hydrolysis under normal use conditions proceeds slowly. The hydrolysis is 100—1000 times faster with trichloroethane dissolved in the water phase than vice versa. Refluxing 1,1,1-trichloroethane with ferric and gallium chloride... 

We have not demonstrated quantitative phase separation of salt from metal in the oxidation step. Approximately 5% of the gallium was carried over from the feed to the product after the calcium reduction. We are now scaling-up the 100-g experiments to plant-size equipment using magnesia crucibles in the equipment shown in Figure 3. 

Most of these compounds were originally prepared by liquid-phase epitaxy. That process is now largely replaced by MOCVD, particularly in the case of gallium arsenide, gallium arsenic phosphide, and gallium aluminum phosphide. 

Like aluminum, gallium forms a series of GaYX compounds (Y = S,Se,Te X = Cl,Br,I) (160). Hardy and Cottreau (165) noticed that at least GaSCl and GaSBr do not correspond exactly to this stoichiometry. These phases are halogen-rich, according to the formula GagSgXn (X = Cl,Br). 

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