This paper describes thermal modeling of Vapor Compression Refrigeration System using R134a in primary circuit and AL2O3-Water based nanofluids in secondary circuit. The model uses information of the secondary fluids input conditions geometric characteristics of the system, size of nanoparticles and the compressor speed to predict the secondary fluids output temperatures, the operating pressure...

Al2O3 and Al2O3-ZrO2 coatings were deposited on stainless steel using atmospheric plasma spraying. The influence of arc current zirconia addition the surface morphology coating, phase composition tribological properties under dry sliding conditions investigated. reduced roughness coatings. X-ray diffraction measurements indicated that composed β-Al2O3, α-Al2O3, γ-Al2O3 phases. led to formation ...

We have demonstrated a flexible resistive random access memory unit with trilayer structure by atomic layer deposition (ALD). The device unit is composed of Al2O3/HfO2/Al2O3-based functional stacks on TiN-coated Si substrate. The cross-sectional HRTEM image and XPS depth profile of Al2O3/HfO2/Al2O3 on TiN-coated Si confirm the existence of interfacial layers between trilayer structures of Al2O3...

The properties of 20 wt % CeO2 and 21 wt % Ce0.5Zr0.5O2 films, deposited onto a γ-Al2O3 by Atomic Layer Deposition (ALD), were compared to bulk Ce0.5Zr0.5O2 and γ-Al2O3-supported samples on which 20 wt % CeO2 or 21 wt % CeO2–ZrO2 were deposited by impregnation. Following calcination to 1073 K, the ALD-prepared catalysts showed much lower XRD peak intensities, implying that these samples existed...

In this paper, overall heat transfer coefficient and friction factor of water based γ-Al2O3 nanofluid in a double tube counter flow heat exchanger have been measured experimentally under turbulent flow condition. For better dispersion of γ-Al2O3 nanoparticles in distilled water, magnetic stirrer and ultrasonic vibrator (with a power of 240 kW and frequency of 35 kHz) were implemented. The stabi...

Highly meso-porous Pt contained γ-Al2O3 nanostructure was prepared by a combined sol gel-pyrolysis method in the presence of polyvinylpyrrolidone and Pluronic p123 as surfactant. The surface of the prepared nanostructure was decorated with 1-Butyl-3-methylimidazolium hexafluorophosphate ([BMM]PF6) ionic liquid to enhance the sorption capacity and prevent the poisoning of the catalytic active si...

Aluminum sulfate nano structures have been prepared by solution combustion synthesis using aluminum nitrate nonahydrate (Al(NO3)3.9H2O) and ammonium sulfate ((NH4)2SO4). The resultant aluminum sulfate nano structures were calcined at different temperatures to study thermal  decomposition of aluminum sulfate. The crystallinity and phase of  the as-synthesized and calcined samples were char...

Connecting prostheses to the implant abutments has become a concern and achieving a satisfactory retention has been focused in cement-retention prostheses recently. Sandblasting is a method to make a roughened surface for providing more retention. The aim of this study was to compare effects of nano and micro airborne abrasive particles (ABAP) in roughening surface of implant abutments and furt...