The chemoselective continuous gas phase (T = 573 K; P = 1 atm) hydrogenation of nitroarenes (p-chloronitrobenzene (p-CNB) and m-dinitrobenzene (m-DNB)) has been investigated over a series of oxide (Al2O3 and TiO2) supported Au and Ni-Au (1 : 10 mol ratio; 0.1-1 mol% Au) catalysts. Monometallic supported Au with mean particle size 3-9 nm promoted exclusive formation of p-chloroaniline (p-CAN) an...

Excellent mechanical properties and fatigue performance of Al/Al2O3 metal-based nanocomposites caused to introduce this material as a good candidate for various applications. In this regard, the preparation and characterization of this composite can be considered as a hot issue for research. The study was carried out in several steps including: (i) preparation of Al/Al2O3 metal-based nanocompos...

The main purpose of this study is to perform numerical simulation of nanofluids as the coolant in VVER-440 fuel rod bundle. The fuel rod bundle contains 60 fuel rods with length of 960 mm and 4 spacer grids. In VVER-440 fuel rod bundle the coolant fluid (water) is in high pressure and temperature condition. In the present Thermo-hydraulic simulation, water-AL2O3 nanofluids containing various vo...

The use of nanoparticles, including metal oxide surfaces, as asphaltene adsorbents is a potential method of removing and/or upgrading asphaltenes. The adsorption of two asphaltene types, extracted from two types of Iranian crude oil, onto nanoparticles (TiO2, SiO2, and Al2O3) are assessed and the thermal behavior of the adsorbed asphaltenes is examined under an oxidizing atmosphere through ther...

Turbulent mixed convection of a nanofluid (water/Al2O3, Φ=.02) has been studied numerically. Two-phase mixture model has been used to investigate the effects of nanoparticles mean diameter on the flow parameters. Nanoparticles distribution at the tube cross section shows that the particles are uniformly dispersed. The non-uniformity of the particles distribution occurs in the case of large nano...

Double-diffusive mixed convection in a lid-driven square enclosure filled with Al2O3-water is numerically investigated. Two-dimensional nonlinear governing equations are discretized using the control volume method and hybrid scheme. The equations are solved using SIMPLER algorithm. The results are displayed in the form of streamlines, isotherms, and iso-concentrations when the Richardson number...

In this paper, we report a new method to prepare the polymer/inorganic nanoparticle composites using electron irradiation-induced polymerization. The mixture of nanoparticles and MMA solution were co-irradiated by 1.6 MeV electron beam to a dose of 10, 20 and 30 kGy at a dose-rate of 60 kGy/h in air at room temperature. The products after irradiation were extracted using a soxhlet extractor wit...

In this paper, second law analysis for calculations of the entropy generation due to the flow andheat transfer of water-Al2O3 and ethylene glycol-Al2O3 nanofluids inside annuli is presented. Thephysical properties of the nanofluids are calculated using empirical correlations. Constant heatfluxes at inner surface of the annuli are considered and fully developed condition for fluid flowand heat t...

Phase stability of transition metal nanoparticles during exposure to elevated temperature and gaseous environment is a highly relevant topic in catalytic research with broad implications for rationalization of catalytic properties and design of new catalytic materials. For Pd based catalysts, the phase stability under oxidizing environment represents an important topic as many Pd based catalyst...