A new sol±gel route was applied to prepare alumina ®lms by using AlCl3 ́6H2O as starting material and acetylacetone (AcAc) as additive. Our research results show that AcAc and aluminum form a complex compound in the sol, which makes the sol very stable. Meanwhile, the complex structure prevents the decomposition going on quickly during the sintering process and the obtained ®lms are free of crac...

Polycrystalline Fe-doped alumina (Al2O3) ceramics have been produced and used as a substrate for organized carbon nanotubes (CNTs) growth by catalytic chemical vapor deposition (CCVD). In these substrates, Fe cations, which are the catalyst source, are initially substituted to Al in a-Al2O3, instead of being simply deposited as a thin Fe layer on the surface of the substrate. The selective redu...

Articles you may be interested in First-principle calculation and assignment for vibrational spectra of Ba(Mg1/3Nb2/3)O3 microwave dielectric ceramic J. Melting of-Al2O3 and vitrification of the undercooled alumina liquid: Ab initio vibrational calculations and their thermodynamic implications Ab initio many-body study of the electronic and optical properties of MgAl2O4 spinel

A continuous process for the preparation of structurally well-defined uniform alumina (Al2O3) nanotubes was developed. The present nanofabrication approach is based on pulse anodization of aluminum by using sulfuric acid and provides unique opportunity for a facile tailoring of the length of nanotubes by controlling the pulse duration.

The CaO-SiO2-MgO-Al2O3 slags with high alumina content are widely applied in various pyrometallurgical processes. However, for super-high-alumina slags, especially those of more than 25 wt%, there is a lack relevant studies about the properties slag. melting behavior, viscosity, structural property, and crystallization behavior high-alumina slag fixed MgO 11.13 wt% Al2O3 from 27.61 to 40 were i...

We study a crystalline epitaxial alumina thin film with the characteristics of a spinel-type transition Al2O3(100) surface by using atom-resolved noncontact atomic force microscopy and density functional theory. It is shown that the films are terminated by an Al-O layer rich in Al vacancies, exhibiting a strong preference for surface hydroxyl group formation in two configurations. The transitio...

The aim of this research was to characterize titanium surfaces blasted with aluminum oxide (Al2O3) particles using the KS 400 digital image processing program. Samples of grade II titanium plates were submitted to blasting processes using particles of Al2O3, and treated with a hydrofluoric acid-based solution. Three digital images from each sample surface were obtained using Scanning Electron M...

The high-temperature oxidation of Hf-modified NiAl alloy at 950 °C results in the formation γ-Al2O3 and θ-Al2O3. Exclusive HfO2 particles is observed adherent γ-Al2O3/NiAl interface. By contrast, θ-Al2O3/NiAl interface multi-layered oxide growth consisting alternate thin thick layers θ-Al2O3 NiAl2O4 along with dispersed layers. This difference elucidated by first-principle calculations showing ...

We present broad-band 24, 70 and 160 μm photometry, 5-35 μm and 55-90 μm spectra of the eruptive variable V4332 Sgr from Spitzer observations. The distinguishing feature of the 5-35 μm spectrum is an unusually broad absorption feature near 10 μm at the position generally associated with silicate-rich dust. Through radiative transfer modeling, we show that this broad feature cannot arise from si...

The Minnesota Nano Center’s Keller Hall facility includes an atomic layer deposition (ALD) machine that is capable of depositing uniform alumina (Al2O3), hafnium oxide (HfO2), silicon dioxide (SiO2), zinc oxide (ZnO), and titanium dioxide (TiO2). ALD works by building alternate layers on a film using two different precursor gases – one usually supplying the metallic atoms and water vapor (H2O) ...