Source code and simulation data for the prediction of the electrodeposition mechanism of nanostructured metallic coatings.

This data article presents a simulation model based on quantum mechanics and energy potentials for obtaining simulation data that allows, from the perspective of materials informatics, the prediction of the electrodeposition mechanism for forming nanostructured metallic coatings. The development of the research is divided into two parts i) the formulation (Quantum mechanical model and Corrected model for electron prediction; using a modified Schrödinger equation) and ii) the implementation of the theoretical prediction model (Discretization of the model). For the simulation process, the finite element method (FEM) was used considering the equation of electric potential and electroneutrality with and without the inclusion of quantum leap. We also provide the code to perform QM simulations in CUDA®, and COMSOL® software, the simulation parameters, and data for two metallic arrangements of chromium nanoparticles (CrNPs) electrodeposited on commercial steel substrate. (CrNPs-AISI 1020 steel and CrNPs-A618 steel). Data collection shows the direct relationship between applied potential (VDC), current (A), concentration (ppm), and time (s) for the homogeneous formation of the coating during the electrodeposition process, as estimated by the theoretical model developed. Their potential reuse data is done to establish the precision of the theoretical model in predicting the formation and growth of nanostructured surface coatings with metallic nanoparticles to give surface-mechanical properties.

Solubility Enhancement of a Poorly Water Soluble Drug by Forming Solid Dispersions using Mechanochemical Activation.

Mechanochemical activation is a practical cogrinding operation used to obtain a solid dispersion of a poorly water soluble drug through changes in the solid state molecular aggregation of drug-carrier mixtures and the formation of noncovalent interactions (hydrogen bonds) between two crystalline solids such as a soluble carrier, lactose, and a poorly soluble drug, indomethacin, in order to improve its solubility and dissolution rate. Samples of indomethacin and a physical mixture with a weight ratio of 1:1 of indomethacin and lactose were ground using a high speed vibrating ball mill. Particle size was determined by electron microscopy, the reduction of crystallinity was determined by calorimetry and transmission electron microscopy, infrared spectroscopy was used to find evidence of any interactions between the drug and the carrier and the determination of apparent solubility allowed for the corroboration of changes in solubility. Before grinding, scanning electron microscopy showed the drug and lactose to have an average particle size of around 50 and 30 µm, respectively. After high speed grinding, indomethacin and the mixture had a reduced average particle size of around 5 and 2 µm, respectively, showing a morphological change. The ground mixture produced a solid dispersion that had a loss of crystallinity that reached 81% after 30 min of grinding while the drug solubility of indomethacin within the solid dispersion increased by 2.76 fold as compared to the pure drug. Drug activation due to hydrogen bonds between the carboxylic group of the drug and the hydroxyl group of lactose as well as the decrease in crystallinity of the solid dispersion and the reduction of the particle size led to a better water solubility of indomethacin.

Small bimetallic (Pt/Pd) particles by biosynthesis: transmission electron microscopy and quantum mechanical analysis.

Bimetallic Pd/Pt nanoparticles were synthesized by bio-reduction method. The structural characterizations were performed by high resolution transmission electron microscope and energy dispersive spectroscopy. The size distribution, shapes, structures and elemental distribution were studied for the synthesized samples. Molecular simulation methods based on quantum mechanics have been applied to acquire the further information on their structural stability, electronic properties etc. The results show that the particle size for the pH = 4 was bimodal with an average particle size of 3.2 nm and a variance of 1.8 nm. While for pH is 7 the average is 3.9 nm about the variance increase up to 3.7 nm, and larger particles can be found. By the HREM micrographs, it is identified fcc-like clusters with a few planar defects, which may be pure Pd or Pt, or bimetallic Pd/Pt. Theoretically the most stable configuration corresponds to the Pd18Pt37 eutectic-like structure, which implies a cluster in cluster form.

Synthesis and characterisation of YSZ-Al2O3 nanostructured materials.

In this work a co-precipitation route was used to synthesise two yttria-stabilised-zirconia (YSZ) phases with different concentrations of alumina (Al2O3). A tetragonal, with 3 mol% yttria, and a cubic, with 8 mol% yttria, phases were added with alumina in different weight proportions, 90/10, 80/20, 70/30, and 60/40, respectively. After synthesised, products were sintered in a range 800-1100 degrees C for different intervals of time. Compounds were characterised by X-ray diffraction, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Rietveld refinements, using FULPROF-Suite software, were carried out to obtain the cell parameters and structural characterisation of products.

Structural selection and amorphization of small Ni-Ti bimetallic clusters.

Classical molecular dynamics simulation is used for structural thermodynamic analysis of Ni-Ti bimetallic clusters. Experimental observation for the nanoclusters synthesized by the bioreduction method is used to consolidate the conclusion. The results demonstrate that Ni-Ti nanoclusters as small as 2-3 nm are not energetically favorable for common ordered geometrical arrangements such as cuboctahedron, decahedron, and icosahedron, though they can be synthesized experimentally. For the elemental distribution, Ni and Ti tend to aggregate separately. In the cases under study, eutectic-like and Ni-core/Ti-shell structures can keep their basic shape and elemental distribution during long periods of relaxation at room temperature. For other cases such as solid solution and Ti-core/Ni-shell, the structures amorphized and the elements tend to distribute uniformly even though they are at temperatures as low as room temperature. Experimental evidence was obtained by the analysis of biosynthesized nanoparticles using transmission electron microscopy techniques. This allowed determination of the partial amorphized structures of small bimetallic particles with cubic and multiple twined-like structures.