English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Microstructural properties of white bauxite from Montenegro were investigated. XRD analysis showed the presence of allophane (Al2O3 · 2SiO2 · 3H2O) and gibbsite (γ-Al(OH)3). The allophane phase showed very broadened diffraction lines, thus indicating poor crystallinity as well as very fine nanoparticles in this phase. Upon heating of natural allophane/gibbsite at 1000 °C mullite (Al6Si2O13) was formed, but with a lower degree of crystallinity. FT-IR spectra of allophane, gibbsite and mullite were interpreted. FE-SEM images of natural allophane/gibbsite showed a dominantly amorphous-like morphology. Upon heating of natural allophane/gibbsite two-dimensional (2D) microstructure was visible. EDS analysis showed traces of calcium, potassium, magnesium and iron. The 57Fe Mössbauer spectrum of iron traces showed a small relative intensity magnetic splitting component due to the presence of hematite and a central quadrupole doublet due to the presence of Fe3+ ions substituted for Al3+ in octahedral positions and/or a superparamagnetic fraction of hematite particles. The possible geochemical mechanism of white bauxite formation in Montenegro is discussed.

Microstructural Properties of Natural Allophane/Gibbsite from a White Bauxite Deposit in Montenegro