The introduction of 0.5–1.0 wt.% graphite to the powders prepared by Self-propagating High-temperature Synthesis (SHS) is found be highly beneficial for removal oxide impurities (from 2.7-8.8 0.2–0.5 wt.%) during spark plasma sintering (1950°C/20 min, 20 MPa) (Hf0.2Mo0.2Ta0.2Nb0.2Ti0.2)B2 and (Hf0.2Mo0.2Ta0.2Zr0.2Ti0.2)B2 ceramics. Concurrently, consolidation level achieved enhanced from about ...

In this work, a reaction coupling self-propagating high-temperature synthesis (RC-SHS) method was developed for the in situ controlled synthesis of novel, high activity TiB2/(TiB2-TiN) hierarchical/heterostructured nanocomposites using TiO2, Mg, B2O3, KBH4 and NH4NO3 as raw materials. The as-synthesized samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM)...

The review presents synthetic approaches to modern rhenium-based catalysts. Creation of an active center is considered as a process of obtaining a nanoparticle or a molecule, immobilized within a matrix of the substrate. Selective chemical routes to preparation of particles of rhenium alloys, rhenium oxides and the molecules of alkyltrioxorhenium, and their insertion into porous structure of ze...

Reachability analysis of stochastic hybrid systems (SHS) is an important problem because it provides a formal framework to analyze complex systems. Biodiesel production is a realistic biochemical process that can be modeled and analyzed using SHS methods. Analysis of a biodiesel production system is important to understand and analyze because demand for biofuels is growing, and economical, effi...

Specific associations among perceived stress and hardiness can reflect the characteristics of workers in particular professions. The goals of this research were to analyze sets of correlations between the aspects of hardiness and experienced stress, separately for two subsamples of subjects in the research, and on the entire sample. Then, the goal was to determine the correlations among the asp...

In this paper, we propose a framework to analyze Markov reward models, which are commonly used in system performability analysis. The framework builds on a set of analytical tools developed for a class of stochastic processes referred to as Stochastic Hybrid Systems (SHS). The state space of an SHS is comprised of: i) a discrete state that describes the possible configurations/modes that a syst...