Barium aluminate titanate

The electrorucs industry requires the manufacture of ceramics such as barium aluminate as lightning protectors by the action of alumina on barium carbonate or of the dielectric material as condensers such as barium titanate, which is prepared by a solid-solid reaction and is more economical [NIE 94] than other methods, by the following reaction ... 

In addition to the above, preparation in w/o microemulsions of nanoparticles of various other types of compounds, viz. silica-coated iron oxide, Fe203-Ag nanocomposite, oxides of ytrium, erbium, neodymium, vanadium and cobalt, titanates of barium and lead, ferrites of barium, strontium, manganese, cobalt and zinc, oxide superconductors, aluminates, zirconium silicate, barium tungstate, phosphates of calcium, aluminium and zinc, carbonates of calcium and barium, sulphides of molybdenum and sodium, selenides of cadmium and silver etc. have been reported. Preparative sources and related elaboration can be found in [24]. 

The matrices for trace analysis are generally restricted to silica, alumina, aluminosilicates, cobalt aluminate, limestone, zircon, barium titanate, and zirconia. Sample preparation for the techniques below is similar to those for full analysis by wet methods above, but using purer reagents. 

Among the multiple oxide particles, barium titanate has been successfully prepared from reverse microemulsions (Herrig and Hempelmann, 1996 Beck et al., 1998) by using isopropanolic solution of Ba- and Ti-alkoxides in 1 1 molar ratio, cyclohexane as the oil phase, and various non-ionic surfactants. Such particles were nanometric (less than 20 nm) in size. A series of nanoparticulate aluminates of transition metals Co, Ni and Cu have been synthesized from microemulsions by Meyer et al. (1999). The noteworthy point in this synthesis is the application of heterobimetallic alkoxides as the single source materials of the cations in each case. 

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