Determination of total iron binding capacity of serum by capillary electrophoresis

A capillary electrophoresis (CE) technique for determining total iron binding capacity (TIBC) of serum has been developed. The optimum serum pretreatment involves the following major steps: at first, saturate serum transferrin with Fe+3; then, dissociate them completely after removing excess unbound Fe. Finally, complex the released iron with phenanthroline, a chromophore, to make suitable for the CE analysis. Ammonium acetate (pH = 5.0) was used as CE background electrolyte solution. In this system, a good linear correlation coefficient was maintained over the range 0.5 similar to 10 mu M (r = 0.9979, n =12). Seven adult serum samples were studied and the TIBC parameters measured. In the present system, 10 similar to 30 mu L serum is sufficient for determination. The study shows that the CE technique described is a powerful method for rapid, efficient, sensitive and reliable analysis and hence particularly suitable for clinical application.

The structure of nano sized poorly-crystalline iron oxy-hydroxides

In this thesis the structures of three nano sized poorly-crystalline iron oxy-hydroxides, feroxyhyte, ferrihydrite and schwertmannite, are studied and analyzed with the aim of clarifying some dubious structural features. The widely used Rietveld re�nement and EXAFS analysis are employed in order to address the consistency of the structural models proposed for these materials, one of which, feroxyhyte, is suggested in this thesis. Furthermore, a new computer program exploiting the Reverse Monte Carlo algorithm and the Debye Scattering Equation is presented and used in order to analyze the elusive structures of these iron oxy-hydroxides.

Hepcidin as a therapeutic tool to limit iron overload and improve anemia in β-thalassemic mice.

Excessive iron absorption is one of the main features of β-thalassemia and can lead to severe morbidity and mortality. Serial analyses of β-thalassemic mice indicate that while hemoglobin levels decrease over time, the concentration of iron in the liver, spleen, and kidneys markedly increases. Iron overload is associated with low levels of hepcidin, a peptide that regulates iron metabolism by triggering degradation of ferroportin, an iron-transport protein localized on absorptive enterocytes as well as hepatocytes and macrophages. Patients with β-thalassemia also have low hepcidin levels. These observations led us to hypothesize that more iron is absorbed in β-thalassemia than is required for erythropoiesis and that increasing the concentration of hepcidin in the body of such patients might be therapeutic, limiting iron overload. Here we demonstrate that a moderate increase in expression of hepcidin in β-thalassemic mice limits iron overload, decreases formation of insoluble membrane-bound globins and reactive oxygen species, and improves anemia. Mice with increased hepcidin expression also demonstrated an increase in the lifespan of their red cells, reversal of ineffective erythropoiesis and splenomegaly, and an increase in total hemoglobin levels. These data led us to suggest that therapeutics that could increase hepcidin levels or act as hepcidin agonists might help treat the abnormal iron absorption in individuals with β-thalassemia and related disorders.

Optimizing the operation of straight-grate iron-ore pellet induration systems using process models

Mathematical models of straight-grate pellet induration processes have been developed and carefully validated by a number of workers over the past two decades. However, the subsequent exploitation of these models in process optimization is less clear, but obviously requires a sound understanding of how the key factors control the operation. In this article, we show how a thermokinetic model of pellet induration, validated against operating data from one of the Iron Ore Company of Canada (IOCC) lines in Canada, can be exploited in process optimization from the perspective of fuel efficiency, production rate, and product quality. Most existing processes are restricted in the options available for process optimization. Here, we review the role of each of the drying (D), preheating (PH), firing (F), after-firing (AF), and cooling (C) phases of the induration process. We then use the induration process model to evaluate whether the first drying zone is best to use on the up- or down-draft gas-flow stream, and we optimize the on-gas temperature profile in the hood of the PH, F, and AF zones, to reduce the burner fuel by at least 10 pct over the long term. Finally, we consider how efficient and flexible the process could be if some of the structural constraints were removed (i.e., addressed at the design stage). The analysis suggests it should be possible to reduce the burner fuel lead by 35 pct, easily increase production by 5+ pct, and improve pellet quality.

Micromagnetic simulation of domain walls in iron films

The micromagnetic structure and energy of 180° domain walls spanning laminar crystals of iron having (100) or (110) surfaces and ranging in thickness from 145 to 580 nm have been investigated by numerical integration of the Landau-Lifshitz-Gilbert equation. Stable equilibrium structures with two flux symmetries were obtained for both crystal orientations at all thicknesses studied.

Computational fluid dynamics: advancements in technology for modeling iron and steelmaking processes

Computational fluid dynamics (CFD) software technology has formed the basis of many investigations into the behavior and optimization of primary iron and steelmaking processes for the last 25+ years. The objective of this contribution is to review the progress in CFD technologies over the last decade or so and how this can be brought to bear in advancing the process analysis capability of primary ferrous operations. In particular, progress on key challenges such as compute performance, fluid-structure transformation and interaction, and increasingly complex geometries are highlighted.

Synthesis and spectroscopic investigation of iron(III) complexes of N'-(thioaroyl)pyridine-2-carbohydrazides

A new series of iron(III) complexes [Fe(L(1))(HL(1))], [Fe(L(1)) Cl]; [H2L(1) = N'-(2-methoxythiobenzoyl)pyridine-2-carbohydrazide], [Fe(L(2))(acac)], [Fe(HL(2))2 Cl]; [H2L(2) = N'-(4-methoxythiobenzoyl)pyridine-2-carbohydrazide] and [Fe(L(3)) (acac)]; [H2L(3) = N'-(2-hydroxythiobenzoyl)pyridine-2-carbohydrazide] were prepared by stirring/refluxing/mixing the respective ligand with FeCl3/Fe(acac)3 in chloroform/methanol. All the compounds were characterized by elemental analyses, magnetic susceptibility, IR, UV and Mossbauer spectral data. The complexes high/low spin state and have tetrahedral/octahedral geometry.