This study investigated the optimum conditions for the leaching of manganese-rich iron ore for subsequent beneficiation studies in laboratory scale. The experiments were carried out by varying the concentration of H2 SO4 solution and the leaching temperature. The properties of the iron ore was characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM)...

We have synthesized Deltalac-acetogenins that are new acetogenin mimics possessing two n-alkyl tails without an alpha,beta-unsaturated gamma-lactone ring and suggested that their inhibition mechanism may be different from that of common acetogenins [Hamada et al. (2004) Biochemistry 43, 3651-3658]. To elucidate the inhibition mechanism of Deltalac-acetogenins in more detail, we carried out wide...

Reactive oxygen species (ROS) are versatile small molecules that under normal homeostatic control are essential for physiological signaling, whereas an improper balance can lead to aging and age-related diseases. A main regulatory mechanism for the ROS hydrogen peroxide (H2O2) is associated with heme enzymes called catalases. These metalloenzymes dismutate two molecules of H2O2 via the proposed...

Density functional theory calculations have been performed to investigate the detailed mechanism of the carbonyl hydrogenation catalyzed by the first well-defined bifunctional iron catalyst. The catalytic reaction proceeds by hydrogen transfer and dihydrogen activation. The hydrogen transfer reaction occurs via the bifunctional mechanism in which the two hydrogen atoms attached on the Fe and O ...

Cyclopropanone hydrate irreversibly inactivates horseradish peroxidase in a time-dependent manner in the presence of oxidizing agent, hydrogen peroxide. The inhibition reaction is a second order reaction of cyclopropanone hydrate with compound I, the 2 electron-oxidized form of peroxidase, and results in covalent modification of the heme cofactor. A new propionic acid side chain is substituted ...

A new tetradentate Schiff base-like ligand H2L (1) ((E,E)-dimethyl-2,2′-[1,2-phenylenebis(aminomethylidyne)]bis[3-oxobutanoate]) was synthesised and structurally characterised. Its reaction with iron(II) acetate leads to the formation of the octahedral N2O4-coordinated complex [FeL(MeOH)2] (2). The complex is a pure high-spin (HS) compound as is evident from magnetic measurements and X-ray crys...

The objective of this study was to identify a potential mechanism for S-nitrosation of proteins. Therefore, we assessed S-nitrosation of bovine serum albumin by dinitrosyl-iron-di-L-cysteine complex [(NO)2Fe(L-cysteine)2], a compound similar to naturally occurring iron-nitrosyls. Within 5-10 min, (NO)2Fe(L-cysteine)2 generated paramagnetic albumin-bound dinitrosyl-iron complex and S-nitrosoalbu...

abstract                                                                               the new drug delivery systems have been developed, which can remain in the stomach for prolonged period of time. the effervescent floating tablet is one of these systems. iron deficiency anaemia is a common disease in the world. ferrous sulphate is the most common ferrous preparation used to treat and prevent...

Although the competitive mechanism for Meisenheimer complex formation during the reaction of 2,4,6-trinitroanisole with methoxide ion in methanol is generally accepted, no kinetic evidence has been presented to rule out a reversible consecutive mechanism. Simulation of the competitive mechanism revealed that a fractional order in [MeO(-)] is predicted by the latter. Conventional pseudo-first-or...