Concrete is susceptible to cracking owing to drying shrinkage, freeze-thaw cycles, delayed ettringite formation, reinforcement corrosion, creep and fatigue, etc. Since maintenance and inspection of concrete infrastructure require onerous labor and high costs, self-healing of harmful cracks without human interference or intervention could be of great attraction. The goal of this study is to expl...

Vanadium is distributed widely and scarcely (150 ppm) on the earth. Its major applications are in steelmaking, dye-production and catalyst-fabrication industries. With the ever-increasing demand for this metal, secondary resource-exploitation of such waste materials as spent catalysts is recommended. Many reactions are involved in vanadium-extraction from these resources. Since roasting in comp...

Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface...

The mechanism of dimethyl carbonate (DMC) synthesis from oxidative carbonylation of methanol over Cu-exchanged Y zeolite has been investigated using in situ infrared spectroscopy and mass spectrometry under transient-response conditions. The formation of DMC is initiated by reaction of molecularly adsorbed methanol with oxygen to form either monoor di-methoxide species bound to Cu+ cations. Rea...

A theoretical analysis of the mechanism of dimethyl carbonate (DMC) synthesis via oxidative carbonylation of methanol on Cu-exchanged Y zeolite, Cu-Y, was explored using density functional theory. These calculations show that methanol adsorbs in the presence of oxygen to form coadsorbed methoxide and hydroxide species and dimethoxide species on extraframework Cu+ cations. DMC can form by CO add...

Abstract This short perspective summarizes recent findings on the role of residual lithium present surface layered Ni-rich oxide cathode materials in liquid- and solid-electrolyte based batteries, with emphasis placed carbonate species. Challenges future research opportunities development carbonate-containing protective nanocoatings for inorganic solid-state battery applications are also discus...

Strontium sorption to amorphous silica and goethite was measured as a function of pH and dissolved strontium and carbonate concentrations at 25 degrees C. Strontium sorption gradually increases from 0 to 100% from pH 6 to 10 for both phases and requires multiple outer-sphere surface complexes to fit the data. All data are modeled using the triple layer model and the site-occupancy standard stat...

The aim of this work is to model the occurrence and intensity of calcium carbonate loss in calcareous forest soils under Mediterranean conditions. We have used 193 Spanish forest soils found on limestone parent material considered highly calcareous materials. This data set came from FOREDAF, a database containing 2200 complete soil profiles and all of them covered by forest stands (mainly domin...

AN exTiNCTiON eVeNT 65 MilliON ye Ars AgO Sixty-five million years ago, a comet slammed into the Yucatán Peninsula, just north of what is now the Mexican city of Merida (see Pope et al., 1998 for a review). This comet, perhaps six miles in diameter, would have ejected enough soot and dust into the atmosphere to blot out the sun for months or longer. The ensuing cold and darkness would have caus...

We confirm the presence of liquid calcium carbonate precursor species in absence additives gas diffusion systems.