First-principles calculations of the energy of various crystal structures of Fe, Ni and ordered Fe–Ni compounds with different stoichiometries have been performed by the linearized augmented plane wave (LAPW) method in the generalized gradient approximation. The most stable compounds are L12–Ni3Fe, L10–FeNi, C11f–Ni2Fe and C11f–Fe2Ni. The L12–Ni3Fe compound has the largest negative formation en...

For the paper industry, the disposal and management of the yielded sludge are a considerable challenge. In our work, the paper mill sludge-derived magnetically separable heterogeneous catalyst (PMS-Fe-380) was prepared easily through a facile synthesis method. The morphology and structure of PMS-Fe-380 were fully characterized by means of X-ray diffraction, Fourier transform infrared spectrosco...

The concentrations of zinc (Zn), iron (Fe) and copper (Cu) in both human milk and infant formula were determined using a new sample preparation method, by inductively coupled plasma - optical emission spectometry (ICP-OES) and flame atomic absorption spectrometry (FAAS). Human milk samples were diluted in ultrapure water. The infant formula of powder samples (suitable for an infant 1-6 months o...

A combined procedure for separating Fe and Hf from a single rock digestion is presented. In a two-stage chromatographic extraction process, a purified Fe fraction is first quantitatively separated from the rock matrix using AG-MP-1M resin in HCl. Hafnium is subsequently isolated using a modified version of a commonly applied method using Eichrom LN-Spec resin. Our combined method includes:•Puri...

Abstraet--A new iron oxide dissolution method designed to measure the abundance of "free" Fe oxide phases and associated elements in soils and sediments has been tested. The method employs a ternary complex of Ti(III), citrate, and ethylenediaminetetraacetate (EDTA) as a reductant and bicarbonate as a proton acceptor. The Ti(III)-citrate-EDTA-HCO3 method dissolved more synthetic amorphous ferri...

Highly ordered, vertically oriented Fe3+-doped TiO₂ nanotube arrays (Fe-TNTs) were prepared on Ti-Fe alloy substrates with different Fe contents by the electrochemical anodization method. The as-prepared Fe-TNTs were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and related electrochem...

Existing electrochemical methods for the determination of iron require long deposition times to determine low iron levels. Here a new method, based on catalytic cathodic stripping voltammetry, is described to determine subnanomolar levels of iron in seawater. The new method has a better baseline and is generally simplified, leading to a lower reagent blank and minimized sample handling compared...

This paper describes a type of didactic material used when teaching electromagnetism. The purpose is to guide the students to verify the results of a Finite Element (FE) simulation using those obtained analytically. This procedure has shown to be of great help during their learning of the FE method. The example in this paper uses a 2D analytical method to estimate the magnetic field generated b...

In this study, we validated measurements of free testosterone (fT) and free estradiol (fE(2)) concentrations calculated from total serum concentrations of testosterone (T), estradiol (E(2)), and sex hormone-binding globulin (SHBG), measured by direct, commercial radioimmunoassays, by comparison with reference measurements obtained by dialysis plus an in-house radioimmunoassay after extraction a...

Finite element (FE) models are widely used to predict the dynamic characteristics of aerospace structures. These models often give results that differ from the measured results and therefore need to be updated to match the measured data. FE model updating entails tuning the model so that it can better reflect the measured data from the physical structure being modeled 1. One fundamental charact...