The key factors governing the single-phase or multi-phase structural change behaviors during the intercalation/deintercalation of guest ions have not been well studied and understood yet. Through systematic studies of orthorhombic Fe2(MoO4)3 electrode, two distinct guest ion occupation paths, namely discrete one for Li and pseudo-continuous one for Na, as well as their relationship with single-...

The chemically modified guar gum sulphonic acid (GSA) resin was used for removal and pre-concentration of Zn2+, Cd2+, Fe2+, Pb2+ and Cu2+ ions in aqueous solutions and steel industry effluent from Jodhpur, India. This type of ion exchange resin represents a new class of hybrid ion exchangers with higher stability, reproducibility and selectivity for toxic metal ions. The characterisation of the...

Identifying the metal ions that optimize charge transport and charge density in metal-organic frameworks is critical for systematic improvements in the electrical conductivity in these materials. In this work, we measure the electrical conductivity and activation energy for twenty different MOFs pertaining to four distinct structural families: M2(DOBDC)(DMF)2 (M = Mg2+, Mn2+, Fe2+, Co2+, Ni2+, ...

BACKGROUND Recently developed iron cocatalyst enhancement of dilute acid pretreatment of biomass is a promising approach for enhancing sugar release from recalcitrant lignocellulosic biomass. However, very little is known about the underlying mechanisms of this enhancement. In the current study, our aim was to identify several essential factors that contribute to ferrous ion-enhanced efficiency...

The oxidation of N-hydroxylated compounds may result in production of nitrogen oxides, including nitric oxide (NO). Oxidation may be independent on NO-synthase. Production of nitrites and nitrates via NO from formaldoxime and glyceryl trinitrate was studied and compared. Superoxide ion, ions Fe2+ and Fe3+, methemoglobin and methemoglobin + NADPH + methylene blue, oxyhemoglobin and oxyhemoglobin...

in this study, the blast furnace slag was used as absorbing bed and then, its ionic adsorption was studied. for this reason, various experimental parameters such as ph, contact time and the primary ion concentration were investigated. the remaining concentrations of ions such as; mn2+ and fe2+ in water were measured by atomic adsorption spectroscopy. the chemical and phase composition of slag, ...

A cytosolic protein factor (ferroactivator) facilitates the activation of phosphoenolpyruvate carboxykinase by ferrous ions (Bentle, L. A., and Lardy, H. A. (1977) J. Biol. Chem. 252, 1431-1440). We have extended our studies on the interaction of Fe2+ with this enzyme to establish the conditions under which it is an activator or an inhibitor. Preincubation of phosphoenolpyruvate carboxykinase w...

The role of the 6″-OH (ω-OH) group in the antioxidant activity of flavonoid glycosides has been largely overlooked. Herein, we selected quercitrin (quercetin-3-O-rhamnoside) and isoquercitrin (quercetin-3-O-glucoside) as model compounds to investigate the role of the 6″-OH group in several antioxidant pathways, including Fe2+-binding, hydrogen-donating (H-donating), and electron-transfer (ET). ...

To systematically study the effects of the number of d electrons of the first transition metal ions (Fe, Co, Ni, Cu and Zn) on the formation and stability of metal flavonoid complexes, we took the quercetin/M2+ complex as a model system to investigate the structures and properties of these complexes. Based on considerable structural information obtained through ESI-MSn, all of the first transit...

The effect of several metal ions on the production of diphtheria toxin was tested. By using the gel immunodiffusion system for detecting toxin, a wide range of metal ion concentrations was conveniently surveyed. Five divalent cations, Fe2+, Cu2+, Co2+, Ni2+, and Mn2+ inhibited toxin production within a range of concentrations that did not inhibit growth of the producing strain. Growth and toxin...