Based on a pyrolitic compositional model, the lower mantle is mainly made of ferropericlase, aluminous silicate perovskite, and calcium perovskite. Silicate perovskite transforms into silicate post-perovskite structure just above the core-mantle region, the D" layer. The existence of iron in the lower-mantle minerals can affect a broad spectrum of the minerals’ physical and chemical properties....

For decades it has been debated whether the conversion of synthesis gas to methanol over copper catalysts is sensitive or insensitive to the structure of the copper surface. Here we have systematically investigated the effect of the copper particle size in the range where changes in surface structure occur, that is, below 10 nm, for catalysts with and without zinc promotor at industrially relev...

a total of 148 groundwater samples were collected from bore wells from thirumanimuttar sub-basin for two seasons to identify major geochemical process activated to alter groundwater chemistry. the study revealed relationships with the lithology and anthropogenic process. groundwater in the region was dominated by na – ca – mg and cl and hco3 types. the (ca +mg) versus tz+ plot for both seas...

The present study addresses the direct flotation route for the concentration of a zinc silicate ore. Flotation of hemimorphite faces some challenges due to the similarity of hemimorphite and quartz surface properties. XRD, and XRF analyses, optical mineralogy and SEM with X-ray mapping were performed for characterization. The results showed that the quartz, hemimorphite, calcite and dolomite ar...

Laser-induced breakdown spectroscopy (LIBS) provides an alternative chemical analytical technique that obviates the issues of sample preparation and sample destruction common to most laboratory-based analytical methods. This contribution explores the capability of LIBS analysis to identify carbonate and silicate minerals rapidly and accurately. Fifty-two mineral samples (18 carbonates, 9 pyroxe...

background: it is hypothesized that poor zinc nutritional status is associated with an increased risk of esophageal cancer (ec), but current evidence is contradictory. since some factors may influence zinc absorption, its status may be better evaluated thorough biomarkers. the objectives of this study were to perform a systematic review on the association of zinc biomarkers with ec in observati...