Претраживање
Приказ резултата 21-30 од 125
Planar chromatography of cholic acid-derived cis-trans isomeric bis-steroidal tetraoxanes
(Journal of Planar Chromatography - Modern TLC, 2009)
Seven pairs of cis-trans isomers of bis-steroidal tetraoxanes have been examined by both normal-phase (NP) and reversed-phase (RP) planar chromatography. Unmodified silica gel was used with ethyl acetate-toluene and ethyl ...
Characterization of double oxide system Cu-Cr-O supported on gamma-Al2O3
(Maik Nauka/Interperiodica/Springer, New York, 2009)
Series of alumina supported chromium-copper catalysts were prepared by co-impregnation method. The samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and UV-visible diffuse reflectance ...
Sesquiterpene lactones, lignans and flavones of Centaurea affinis
(Oxford : Pergamon-Elsevier Science Ltd, 2004)
Aerial parts of Centaurea affinis Friv. were collected at Vlasina (east Serbia) in September 1998.
The contributions of high- and low altitude emission sources to the near ground concentrations of air pollutants
(Elsevier Science Inc, New York, 2008)
The scale of transport through the atmosphere depends on the effective height of an emission source, the meteorological conditions and the physico-chemical characteristics of the pollutants. Atmospheric surface temperature ...
Thin layer of Ni-modified 13X zeolite on glassy carbon support as an electrode material in aqueous solutions
(Maik Nauka/Interperiodica/Springer, New York, 2007)
A new type of an electrode material, zeolite modified by the incorporation of Ni or NiO clusters into its cavities, was synthesized by multiple impregnation of zeolite 13X with a Ni-acetylacetonate solution followed by ...
A study of water influence on carbon monoxide adsorption and oxidation on nanocrystals of: γ-Fe2O3, Au/Fe2O 3 and MnxZn1-xFe2O4
(Materials Science Forum, 2006)
In this paper the adsorption and oxidation of CO on nanocrystalline Au/γ-Fe2O3, Au/α-Fe2O3, γ-Fe2O3 and a series of mixed ferrite with Mn xZn1-xFe2O4 composition are investigated. The catalysts were prepared by co-precipitation ...
Preparation of ZrO2 and Al2O3 thin-films on stainless steel by spray pyrolysis
(Research Trends in Contemporary Materials Science, 2007)
We have investigated the deposition of ZrO2 and Al2O3 films on a stainless steel (SS) substrate by spray pyrolysis method. The ZrO2 films were deposited from aqueous solution of zirconium dinitrate oxide. For Al2O3 films, ...
N-type silicon electron mobility and its relationship to the kink effect for nano-scaled SOI NMOS devices
(Materials Science Forum, 2007)
Electron mobility for the silicon-based devices is one of the most important parameters, which determine the behavior of components. Mobility depends on silicon purity, doping level, presence of lattice defects and electric ...
Microstructural properties of PZT thin films deposited on LaNIQ 3-coated substrates
(Materials Science Forum, 2007)
The modified polymeric precursor method (Pechini method) was successfully used for the preparation of epitaxial and polycrystalline ferroelectric Pb(Zr0.52Ti0.48)O3 (PZT) thin films. Films were deposited on LaNiO3 (LNO) - ...
Structural effects in electrocatalysis: Formic acid oxidation at model and real Pt catalysts
(Materials Science Forum, 2006)
Formic acid oxidation was studied at low-index Pt single crystals (model systems) as well as at the platinum catalyst supported on high area carbon (real catalyst) in HClO4. The Pt single crystals were characterized by ...