ten chromite ores from ophiolite complexes in se iran were analyzed mineralogically by xrd, chemically by xrf, and mineral chemistry by epma. the identified paragenesis of silicate minerals of chromite ores with the x-ray diffraction is pronounced differently. it consists of secondary phases formed as serpentine, cr-containing chlorite (kaemmererite), chromic garnet (uarovite) with preserved pa...

Background & Aims of the Study: Phenolic compounds have been extensively used in industries for applications such as petrochemical, oil refineries, papers, plastics, steel, pharmaceuticals, textiles, coal conversion, and so on. Specified amounts of Phenolic compounds are lost in the process of their manufacturing and utilization and often cause environmental pollution problems....

Iron is a limiting factor that controls the phytoplankton biomass of ocean and plays an important role in lipid production microalgae. Elucidating effects different iron valences on microalgae helpful for their commercial production. We investigated growth, photosynthesis, fatty acid profile model diatom Phaeodactylum tricornutum cultured with depleted Fe, Fe2+, Fe2+/Fe3+, Fe3+. Samples were ta...

Ascorbic acid (AA) has antioxidant properties. However, in the presence of Fe2+/Fe3+ ions and H2O2, it may behave as a pro-oxidant by accelerating enhancing formation hydroxyl radicals (•OH). Therefore, this study we evaluated effect AA at concentrations 1 to 200 µmol/L on •OH-induced light emission (at pH 7.4 temperature 37 °C) from 92.6 Fe2+—185.2 EGTA (ethylene glycol-bis (β-aminoethyl ether...

In this study, different oxidation processes UVA-365 nm (photolysis), UV–A/H2O2, UV–A/H2O2/Fe2+, UV–A/S2O8, and UV–A/S2O8/Fe2+ were investigated to compare removal rates efficiencies of Oxytetracycline (OTC). The role the initial concentration oxidants, as well their inhibitory threshold regarding degradation mineralization OTC, was at pH. It found that pH solution had an important in photolysi...

By nonenzymatic model reactions, the influence o f vanadium (V 0 2+, V 0 3~) and other metal ions (A l3+, Fe2+, Fe3+, Zn2+, N i2+, Cr3+) on the transamination of 4,5-dioxovaleric acid (D O VA) with L-alanine (A la ) to 6 -aminolevulinic acid (<5-ALA) and pyruvic acid (P A ) with pyridoxal phosphate (P L P ) is investigated. The examinations o f the partial reactions show that V 0 2+, V 0 3~ and...

The stability of iron ascorbate solutions was investigated, under both anaerobic and aerobic conditions, with the Fe2+ and Fe3+ indicators, respectively ferrozine and mimosine, at different pH values. The species present under the differing conditions were investigated by electron paramagnetic resonance (EPR) and Mössbauer spectroscopy and by gel-filtration chromatography. At physiological pH (...

The first 2-pyridylmethyl pendant armed structurally reinforced cyclam ligand has been synthesized and successfully complexed to Mn2+, Fe2+, and Cu2+ cations. X-ray crystal structures were obtained for the diprotonated ligand and its Cu2+ complex demonstrating pentadentate binding of the ligand with trans-II configuration of the side-bridged cyclam ring, leaving a potential labile binding site ...

Vacuolar iron transporters (VITs) are a poorly understood family of integral membrane proteins that can function in iron homeostasis via sequestration of labile Fe2+ into vacuolar compartments. Here we report on the heterologous overexpression and purification of PfVIT, a vacuolar iron transporter homologue from the human malaria-causing parasite Plasmodium falciparum. Use of synthetic, codon-o...