Ettringite is a hexacalcium aluminate trisulfate hydrate mineral that forms during Portland cement hydration. Its presence plays an important role in controlling the setting rate of the highly reactive aluminate phases in cement paste and has also been associated with severe cracking in cured hardened cement. To understand how it forms and how its properties influence those of hardened cement a...

A solid Ca/Al composite oxide-based alkaline catalyst containing Ca(12)Al(14)O(33) and CaO was prepared by chemical synthesis and thermal activation from sodium aluminate solution and calcium hydroxide emulsion. The effect of calcination temperatures ranging from 120 °C to 1000 °C on activity of the catalyst was investigated. The catalyst calcined at 600 °C showed the highest activity with >94%...

This study looked into the influence of iron nitrate (Fe(NO3)3 on corrosion behavior a 6061 Al alloy treated by plasma electrolytic oxidation coating (PEO). PEO coatings were fabricated samples under AC conditions utilizing an alkaline-aluminate electrolyte containing 0 and 5 gr Fe(NO3)3. Surface examination demonstrated that some Fe2O3 particles effectively integrated layer produced in solutio...

Tris(2-pyridyl)borates are introduced as a new robust and tunable "scorpionate"-type ligand family. A facile synthesis of this hitherto unknown ligand and its complexation to Fe(II) are described; the optical and electrochemical properties of the resulting iron complex are compared to complexes derived from tris(pyrazolyl)borate, tris(2-pyridyl)aluminate, and corresponding charge-neutral ligands.

The desilication of sodium aluminate solutions prior to precipitation aluminum tri-hydroxides is an essential step in the production high purity alumina for production. This study evaluates derived from leaching calcium-aluminate slags with carbonate, using CaO, Ca(OH)2, and MgO fine particles. influence amount CaO used, temperature, comparisons Ca(OH)2 were explored. Laboratory scale test work...

An efficient four-component synthesis of 1,2,4,5-tetrasubstituted imidazoles is described by one-step condensation of an aldehyde, benzil, ammonium acetate and primary aromatic amine with nanocrystalline magnesium aluminate in ethanol under ultrasonic irradiation. High yields, short reaction times, mild conditions, simplicity of operation and easy work-up are some advantages of this protocol.

As the aluminate base [LiAl(TMP)(2)(iBu)(2)] 1 displays halogen tolerance towards substituted aromatics, 4-halo-anisoles have been ortho-aluminated and electrophilically quenched to form synthetically useful multi-heterohalogenated anisoles, with the Al intermediates along the route structurally defined.