besides human dental and skeletal fluorosis, drinking water above permissible levels of fluoride is known to cause a wide range of adverse health effects. in this study, the adsorption of fluoride from aqueous solution onto pretreated zeolite has been studied by using batch test. the large surface area of natural zeolite (i. e., clinoptilolite from miyaneh region, iran) was utilized to create a...

When Fe2+ ions are added to rat-liver microsomes, lipid peroxidation begins after a short lag period. Fe2+-dependent peroxidation in the first few minutes of the incubation can be increased by adding Fe3+, ascorbic acid or Pb2+ ions; these stimulations are not additive. By contrast, Pb2+ ions inhibit peroxidation of microsomes in the presence of Fe3+/ascorbate or Fe3+-ADP/NADPH. In liposomes ma...

Resumo Materiais baseados em oxi-hidróxidos mistos de alumínio e ferro (III) foram preparados pela síntese hidrotérmica a partir da ureia, sais nitrato ou cloreto diferentes razões molares Al3+:Fe3+. Foram avaliadas as propriedades estruturais, morfológicas térmicas dos materiais. As misturas nitratos Al3+ Fe3+ conduziram à formação hematita enquanto que nos materiais obtidos cloretos, fases cr...

a graphene oxide-terpyridine conjugate (gotc) based colorimetric and fluorescent nano-chemosensor was synthesized. it showed high selectivity and sensitivity for fe2+ and fe3+ ions in neutral aqueous solution over other metal ions such as li+, na+, ba2+, ca2+, al3+, cd2+, co2+, cu2+, hg2+, mn2+, ni2+, pb2+, zn2+, cr3+ and ag+. in absorption spectra, upon addition of fe2+ or fe3+, the sensor dis...

The primary phase of the Earth’s lower mantle, (Al, Fe)-bearing bridgmanite, transitions to post-perovskite (PPv) at deep mantle conditions. Despite extensive experimental and ab initio investigations, there are still important aspects this transformation that need clarification. Here, we address transition in (Al3+, Fe3+)-, (Al3+)-, (Fe2+)-, (Fe3+)-bearing bridgmanite using calculations valida...

The increasing number of roles discovered for Al3+ in physiological processes demands an understanding of how Al3+ interacts with compounds in biological systems. Al3+ is expected to complex with oxygen donor ligands, especially phosphates, and it does so in soils, in the gastrointestinal tract, and in cells. The stability of Al3+ complexes has generally been misjudged because of lack of recogn...

Abstract. The theoretical vibrational properties of a series Fe- and Al-bearing lizardite models have been determined at the density functional theory level. Each periodic model displays single cationic impurity substituted an octahedral or tetrahedral site supercell (Mg3Si2O5(OH)4) containing 162 atoms. isovalent Fe2+ for Mg2+ substitution has considered, as well heterovalent Fe3+ Al3+ Si4+. C...

This study aimed to investigate the effect of six chloride salts on butterfly pea flower extract’s anthocyanins stability. The were NaCl, KCl, CaCl2, MgCl2, FeCl3, and AlCl3. samples analyzed using a UV-Vis spectrophotometer observe color degradation change in hue during storage. extraction was done modified method, solutions stored dark vials at room temperature. kinetics benzene derivatives, ...

The effects of polyvalent metal cations on pyrene binding to hydrophobic acid and neutral fractions (HoA and HoN, respectively) of dissolved organic matter (DOM) were elucidated. The DOM was isolated from sewage sludge; pyrene binding was estimated from fluorescence measurements. Isotherms of pyrene binding to both fractions were nonlinear. Pyrene binding was higher for HoN due to the combined ...