Surface Nanostructuring of a CuAlBe Shape Memory Alloy Produces a 10.3 ± 0.6 GPa Nanohardness Martensite Microstructure.

Severe plastic deformation (SPD) has led to the discovery of ever stronger materials, either by bulk modification or by surface deformation under sliding contact. These processes increase the strength of an alloy through the transformation of the deformation substructure into submicrometric grains or twins. Here, surface SPD was induced by plastic deformation under frictional contact with a spherical tool in a hot rolled CuAlBe-shape memory alloy.

Removal of arsenic III and V from laboratory solutions and contaminated groundwater by metallurgical slag through anion-induced precipitation.

Metallurgical slag was used for the simultaneous removal of high concentrations of arsenite and arsenate from laboratory solutions and severely contaminated groundwater. Apart from demonstrating the high efficiency of arsenic removal in presence of competing species, the work aims to explore the physicochemical mechanisms of the process by means of microscopy observation and a detailed statistical analysis of existing kinetic and isotherm equations. Fitting was performed by non-linear least squares using weighted residuals; ANOVA and bootstrap methods were used to compare the models.

Optimization of the synthesis process of an iron oxide nanocatalyst supported on activated carbon for the inactivation of Ascaris eggs in water using the heterogeneous Fenton-like reaction.

An experimental design methodology was used to optimize the synthesis of an iron-supported nanocatalyst as well as the inactivation process of Ascaris eggs (Ae) using this material. A factor screening design was used for identifying the significant experimental factors for nanocatalyst support (supported %Fe, (w/w), temperature and time of calcination) and for the inactivation process called the heterogeneous Fenton-like reaction (H2O2 dose, mass ratio Fe/H2O2, pH and reaction time). The optimization of the significant factors was carried out using a face-centered central composite design.

Inactivation of Ascaris eggs in water using hydrogen peroxide and a Fenton type nanocatalyst (FeOx/C) synthesized by a novel hybrid production process.

Inactivation tests of Ascaris eggs (Ae) were performed using hydrogen peroxide and a Fenton type nanocatalyst supported on activated carbon (AC) (FeOx/C). Blank inactivation tests were also carried out using H2O2 and H2O2/AC as oxidation systems. The FeOx/C nanocatalyst was synthesized through a novel hybrid method developed in this work.

Scanning electron microscopy observation of the substructural evolution of aluminium alloys during cold rolling and partial annealing.

Classical etching techniques for revealing cold deformation and partial recrystallisation in metals have been optimised for optical microscopy, which is limited by its resolution. Detailed studies of the mechanisms involved in recovery and recrystallisation during heat treatment are generally made by transmission electron microscopy. The limitation of this technique, with a few exceptions, is its small field of view and the small fraction of the sample available for inspection.