Ab initio quantum mechanical calculations were performed on Al(OH)3, Al(OH)4, NaAl(OH)4 and related species with varying numbers of explicit water molecules to elucidate the structural, spectral and energetic properties of the possible species. We find that Al(OH)3 reacts with H2O in the gas-phase with an exoergicity of 24.1 kcal/mol to produce Al(OH)3H2O, which has shorter Al-OH distances, lar...

Calcium hexaluminate (CA6) was incorporated into the matrix of magnesio aluminate spinel-alumina (MA-A) via infiltration of a porous preform fabricated from α-Al2O3 and MgO powders with a saturated calcium acetate solution and subsequent firing, forming CA6/(MA-A) functionally composites with graded fracture toughness. Actually, the porous preform was partially and perpendicularly immersed (1/4...

The compositions and molecular structures of anhydrous and hydrated cements are established by using advanced solid-state nuclear magnetic resonance (NMR) spectroscopy methods to distinguish among different molecular species and changes that occur as a result of cement hydration and setting. One- and two-dimensional (2D) solid-state (29)Si and (27)Al magic-angle spinning NMR methodologies, incl...

in this research, the activity of mno, produced during steel making in aluminate-rich slags, was investigated.according to thermodynamic equations and mathematical calculation, a series of relations was obtained forevaluation of oxide activity using masson’s theory. the obtained relations were solved according to levenberg- marquardt method and using matlab software. the results were correlated...

Nanoparticles of strontium aluminate phosphors co-a tivated by Eu2+ and Dy3+ have been prepared by heating theprecursorsobtained fromnitrate salt–ammoniumacetic–urea–gel combustionprocess at temperature of 1150 ◦C in a weak reductive atmosphere of thermal carbon. Transmission electronmicroscope

Aluminum metal is produced by the electrolytic reduction of aluminum oxide (Al2O3), mainly extracted from bauxite ore digested in a hot caustic soda solution. This solution is supersaturated with respect to sodium aluminate and silicate, which react together to form sodalite (3[Na2O⋅Al2O3⋅2SiO2⋅2H2O]⋅Na2CO3) at high temperatures. Heat exchanger tubes are scaled with this compound, which serious...