Atomic layer deposition (ALD) of Al2O3 using trimethylaluminum (TMA) and water on Pd nanoparticles (NPs) was studied by combining in situ quartz crystal microbalance (QCM) measurements, in situ quadrupole mass spectrometry (QMS), and transmission electron microscopy (TEM) with density functional theory (DFT) calculations. TEM images of the ALD Al2O3 overcoated Pd showed conformal Al2O3 films on...

The objective of this study is to numerically investigate the convective heat transfer of water-based Al2O3 nanofluids flowing through a square cross-section duct with a constant heat flux under laminar flow conditions. The effects of nanoparticle concentration and Peclet number on the heat transfer characteristics of Al2O3-water nanofluids are investigated. The nanoparticle diameter is 25 nm a...

Unsteady flow and heat transfer from a circular cylinder in cross-flow is studied numerically. The governing equations are solved by using finite volume method. Reynolds number varies in range of 50 to 200; in this range flow is considered to be laminar and unsteady. Al2O3 nanoparticle with volume fraction in range of 5% to 20% is added to pure water. Effects of adding nanoparticle to pure wate...

One of the main reactions that can be used to reduce greenhouse gases emissions is Reverse Water Gas Shift (RWGS) reaction. Through this reaction CO2 is converted to CO to produce beneficial chemicals such as methanol. In this paper Mo/Al2O3 catalyst was prepared and then promoted with Ni ions through impregnation method to produce Ni-Mo/Al2O3 catalyst. The structures of the catalysts were stud...

the effect of γ-al2o3 nanoparticles on heat transfer rate, baffle spacing and pressure drop in the shell side of small shell and tube heat exchangers was investigated numerically under turbulent regime. γ-al2o3-water nanofluids and pure water were used in the shell side and the tube side of heat exchangers, respectively. since the properties of γ-al2o3-water nanofluids were variable, they were ...

Dynamic viscosity values for three particular water-based nanofluids have been experimental determined using a commercial ‘piston-type’ viscometer. Viscosity data, expressed as a function of temperature and particle volume fraction, are presented for 29nm particle-size CuO-water and Al2O3-water with 36nm and 47nm particle-sizes, temperatures up to 75°C and particle volume fraction up to 9%. In ...

In this study we present new data for the thermal conductivity enhancement in four nanofluids containing 11, 25, 50, and 63 nm diameter Aluminum oxide (Al2O3) nanoparticles in distilled water. The nanofluids were prepared using single step method (that is, by dispersing nanoparticle directly in base fluid) which was gathered in ultrasonic device for approximately 7 h. The transient hot-wire las...

Structures and testing methods for measuring the adhesion strength, minimum bending diameter, and bending fatigue performance of thin-film polymer electronic architectures were developed and applied to Parylene–metal–Parylene systems with and without the moisture barrier Al2O3 [deposited using atomic layer deposition (ALD)]. Parylene–metal– Parylene interfaces had the strongest average peel tes...

In present work a experimental study based on thermosyphon is investigated using a solid nano-particles added to water as a working fluid. Tests are made on a thermosyphon. The experiment was performed in order to measure the temperature distribution and compare the heat transfer rate of the thermosyphon with the nano uid and with pure water. The tested concentration level of the nano-particles...

The Cu/Al2O3 catalyzed ozonation for degrading an endocrine disruptor—alachlor in water was investigated. The Cu/Al2O3 powders were coated on a cordierite honeycomb column, which was taken as the reactor of catalytic ozonation of alachlor. Additional uncatalyzed experiments were carried out and the results were compared to those of the catalytic runs. The experimental results demonstrated that ...