In this study, the effects of silica-based gold-nickel (AuNi@SiO 2) nanohybrid to the production of hydrogen from dimethylamine borane (DMAB) were investigated. AuNi@SiO 2 nanohybrid constructs were prepared as nanocatalysts for the dimethylamine borane dehydrogenation. The prepared nanohybrid structures were exhibited high catalytic activity and a stable form. The resulting nanohybrid, AuNi@SiO 2 as a nanocatalyst, was tested in the hydrogen evolution from DMAB at room temperature. The synthesized nanohybrids were characterized using some analytical techniques. According to the results of the characterization, it was observed that the catalyst was in nanoscale and the gold-nickel alloys showed a homogenous distribution on the SiO 2 surface. After characterization, the turn over frequency (TOF) of nanohybrid prepared for the production of hydrogen from dimethylamine was calculated (546.9 h −1). Also, the prepared nanohybrid can be used non-observed a significant decrease in activity even after the fifth use, in the same reaction. In addition, the activation energy (E a) of the reaction of DMAB catalyzed AuNi@SiO 2 nanohybrid was found to be 16.653 ± 1 kJmol −1 that facilitated the catalytic reaction. Furthermore, DFT-B3LYP calculations were used on the AuNi@SiO 2 cluster to investigate catalyst activity. Computational results based on DFT obtained in the theoretical part of the study support the experimental data.

The aim of this work is to perform a thermal analysis of the operational conditions of a large-scale roller conveyor furnace in a ceramic factory. The entire furnace was divided into three subzones according to the combustion conditions, and the temperature and gas (CO2, H2O vapor, and O2) distributions of each subzone were evaluated. The computational fluid dynamics (CFD) approach was employed to simulate the flow, temperature profile, and heat transfer. The realizable k–ε model was applied for turbulence simulation of the fluid flow coming from the burners. The discrete ordinates method (DOM) and weighted sum of gray gases (WSGG) model were used for simulation of the radiative heat transfer of the furnace. The high accuracy of the simulation methods was validated with the temperature data of the furnace measured by an infrared thermal camera. From the comparisons between the furnace's operating conditions and the numerical simulations, it was concluded that the simulation methods yielded successful results, and relative deviations of up to 22% were observed in the side wall.

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In this study, bimetallic platinum–rhodium nanocomposites supported on graphene oxide (PtRh@GO) were synthesized and used as a catalyst in the dimethylamine borane (DMAB) dehydrogenation.