As a reference, pure magnesium aluminate Mg[Al.sub.2][O.sub.4] spinel was prepared using commercially available powders of MgO and boehmite
(aluminium oxide hydroxide, AlO(OH)), average grain size < 0.77 [micro]m.
There are three main bauxites types -- boehmite
, gibbsite and diaspore, -- which each differ in chemical and physical characteristics, and each have predominance in certain regions of the world.
PLA has been compounded with ammonium polyphosphate, boehmite
, clays, halloysite, talc, silica, and graphite and the resulting materials were characterized to have better thermal, mechanical, and fire resistance performance [6, 9, 11, 28-38], For instance, PLA was reported as flammable and burning with intense dripping during combustion; however, the incorporation of clay and/or expanded graphite rendered PLA composites fire resistant [6, 9], In another study, Kimura and Horikoshi  reported that the developed PLA-based flame-resistant housings for notebook computers showed optimal physical and flammability properties.
Frost, "Thermal decomposition of bauxite minerals: Infrared emission spectroscopy of gibbsite, boehmite
and diaspore," Journal of Materials Science, vol.
Dcbowski et al., "Organically modified aluminophosphates: transformation of boehmite
into nanoparticles and fibers containing aluminodiethylphosphate tectons," Chemistry of Materials, vol.
Their main component is the [gamma]-phase of an alumina boehmite
line (Figure 1(a)).
In a previous study, Katakura and Koide  reported that the treatment of boehmite
, AlO(OH), with HQ in boiling water produces either [alpha]-[Alq.sub.3] or [gamma]-[Alq.sub.3] depending on whether the reaction is allowed to continue for 1h or 90 h, respectively.
Watanabe, "Preparation of transparent superhydrophobic boehmite
and silica films by sublimation of aluminum acetylacetonate," Advanced Materials, vol.
Karvembu, "Copper on boehmite
: a simple, selective, efficient and reusable heterogeneous catalyst for oxidation of alcohols with periodic acid in water at room temperature," Applied Catalysis A: General, vol.
The conducted X-ray studies of sorbents have shown that the sample 3 has the signified crystal phase corresponding to [gamma]-Al[(OH).sub.3] gibbsite with [gamma]-AlOOH boehmite
inclusions while other samples are poorly crystallized or in the X-ray amorphous state (Fig.
(61.) Wang, Z, Gong, J, Ma, J, Xu, J, "In Situ Growth of Hierarchical Boehmite
on 2024 Aluminum Alloy Surface as Superhydrophobic Materials." RSC Adv., 4 (28) 14708-14714 (2014)