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Ni-Mo2C particles supported over hydroxyapatite were synthesized as potential catalysts to hydrogen production applications due their physiochemical properties observed in characterization results, this favorable for biomass gasification. Mo2C particles doped with Ni were synthesized by temperature programmed reaction method at 900 °C under hydrogen reducing atmosphere. Hydroxyapatite support was obtained from thermal extraction of bovine bones, in a temperature range from 700 to 900 °C. Ni-Mo2C impregnation over hydroxyapatite support was made by incipient humidity method. X-ray diffraction analysis determined crystallographic phases of β-Mo2C, NiC and hydroxyapatite. Though, bone organic matter degradation was observed by X-ray diffraction and confirmed by Infrared Spectroscopy with Fourier Transform (FTIR) the final structure of hydroxyapatite was maintained. Finally, textural properties analysis of support showed an increase in porosity structure with the increment of temperature. β-Mo2C and NiC were obtained with similar catalytic activity than noble metals, also nickel improves hydrocarbons bonds rupture. Hydroxyapatite showed high stability and porosity at elevated temperatures attributable to synthesis conditions.

In this paper, an impulse-based Discrete Element numerical Method (iDEM) included in a physics toolbox, has been used to compact virtual aggregates. Firstly, geometrical properties, such as area, aspect ratio, perimeter, minor and major feret, circularity and roundness, of eleven types of coarse aggregates were measured. Then, a mass of each of these aggregates was compacted under vibration. The aggregate packings’ properties, such as aggregate segregation and orientation, porosity, pore -diameter, -tortuosity, -connectivity, -aspect ratio, -circularity, and -vertical distribution, were measured from Computed Tomography scans. Secondly, the aggregates were simulated using a Perlin noise in spherical primitives, which adjusted their geometry until they achieved realistic morphologies and gradations. iDEM detects contacts between complex shapes, including concavities, and computes the interaction between large amounts of complex objects. Results show that the properties from the packing experiments and simulations are highly comparable. This paper demonstrates the capacity of the physics toolbox to simulate granular materials effectively.

The Quaternary Acoculco ( Coevally to the Miocene NE-SW and Pliocene-Quaternary NW-SE tectonic extensional phases, NE-SW and NW-SE transfer faults were developed. NE-SW normal faults and NW-SE strike-slip faults correspond to fault systems optimally oriented with the current stress field, thus, these faults can be considered as potentially active structures controlling magma emplacement and the distribution of volcanic structures at the surface.

The precise, quick and efficient simulation of asphalt concrete is an important step to select asphalt mixtures for a range of applications. A method to create virtual aggregates based on aggregates' topological properties and aggregate skeletons like those of asphalt concrete using a physics engine is proposed. It can produce hundreds of virtual aggregates with shape properties equivalent to these of real ones in a matter of seconds, pack them to a level of compaction like that of the Marshall compactor, and measure properties such as the expected air voids content and number of contacts between the aggregates. In the paper, only aggregates bigger than 2 mm have been considered due to computing efficiency. Besides, it was found that the main factors influencing asphalt compaction are the number of aggregates in the mixture and the amount of dust, or aggregates smaller than 2 mm, which correspond to the parts of the solid skeleton that have not been simulated.