nanosized al2o3 powder is synthesized by thermal metal organic chemical vapor deposition (mocvd)combined withplasma. the effects of reaction temperature, pressure, al(ch3)3 (tma) concentration and reactant gases (co2 and o2) on the characteristics of the synthesized al2o3 powders are investigated. the experimental results demonstrate that very fineal2o3 powders with mean particle size of about ...

Efforts to reduce the carbon footprint associated with cement and concrete production have resulted in a number of promising lower-emission alternatives. Still, research has emphasized small subset potentially useful precursor materials. With goal expanding pool, this work presents results parallel literature mining rate modeling activities. As result mining, materials appropriate SiO2, Al2O3, ...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Pia Sundberg Name of the doctoral dissertation Atomic/molecular layer deposition of hybrid inorganic-organic thin films Publisher School of Chemical Technology Unit Department of Chemistry Series Aalto University publication series DOCTORAL DISSERTATIONS 201/2014 Field of research Inorganic Chemistry Manuscript submitted 11 Se...

Carbon nanotubes±Fe±Al2O3 massive composites have been prepared by hot-pressing the corresponding composite powders, in which the carbon nanotubes are arranged in bundles smaller than 100 nm in diameter and several tens of micrometers long, forming a web-like network around the Fe±Al2O3 grains. In the powders, the quantity and the quality of the carbon nanotubes both depend on the Fe content (2...

Characterization was performed on 60 nm +/3 nm films of atomic layer deposition (ALD) hafnium dioxide (HfO2) and aluminum oxide (Al2O3), and plasma-enhanced chemical vapor deposition (PECVD) silicon nitride (Si3N4) as MIM capacitor dielectric for GaAs HBT technology. The capacitance density of MIM capacitor with ALD HfO2 (2.73 fF/m 2 ) and Al2O3 (1.55 fF/m 2 ) is significantly higher than tha...

We investigate the optical and thermo-optical properties of amorphous TiO2–Al2O3 thin-film bilayers fabricated by atomic layer deposition (ALD). Seven samples of TiO2–Al2O3 bilayers are fabricated by growing Al2O3 films of different thicknesses on the surface of TiO2 films of constant thickness (100 nm). Temperature-induced changes in the optical refractive indices of these thin-film bilayers a...

The influence of catalyst support alumina-silica in terms of different Al2O3 to SiO2 mole ratios containing 20 wt.% Ni on the production of hydrogen and catalyst coke formation from the pyrolysis-catalysis of waste tyres is reported. A two-stage reactor system was used with pyrolysis of the tyres followed by catalytic reaction. There was only a small difference in the total gas yield and hydrog...

These are model studies whose aim is to obtain information that would allow development of new technology for synthesizing monolayers of Al2O3-C with adjusted microstructure on cemented carbides. The Al2O3-C layer will constitute an intermediate layer on which the outer layer of Al2O3 without carbon is synthesized. The purpose of the intermediate layer is to block the cobalt diffusion to the sy...

Al2O3–Ta2O5 nanolaminate films were prepared via atomic layer deposition (ALD) on silicon with a single overall composition and thickness, but with a varying number of Al2O3/Ta2O5 bilayers. The composition of the films was roughly 57% Al2O3 and 43% Ta2O5 and the total film thickness was held at 58 nm, while the number of bilayers was varied from 3 to 192 by changing the target bilayer thickness...

In a common salt-in-polymer electrolyte, a polymer which has polar groups in the molecular chain is necessary because the polar groups dissolve lithium salt and coordinate cations. Based on the above point of view, polystyrene [PS] that has nonpolar groups is not suitable for the polymer matrix. However, in this PS-based composite polymer-in-salt system, the transport of cations is not by segme...