Properties of the Virus of the Tobacco Mosaic on the Si(111) Surface

Abstract

Extended abstract of a paper presented at MC 2007, 33rd DGE Conference in Saarbrücken, Germany, September 2 – September 7, 2007

Adsorption of polar and nonpolar compounds onto complex nanooxides with silica, alumina, and titania

“…[2][3][4] and can be assigned to type II of IUPAC classification [14,17]. This regularity is due to a spherical (but nonideal) shape of nonporous primary particles (average diameter d av = 6.9-52.5 nm for studied oxides, Table 1) forming aggregates (secondary particles of 50-1000 nm in size) and looser agglomerates of aggregates (ternary particles >1 lm in size).…”

“…[1][2][3][4][5][6][7][8]. Their physicochemical properties can be varied on synthesis using small amounts of dopants (typically forming solid solution in a host matrix) or a mixture of different precursors of comparable amounts that form separated or/and interpenetrated phases that can be amorphous or/and crystalline [2,3,6,7].…”

“…Changes in the previously noted structural and morphological characteristics affect the interactions of nanoparticles with their surroundings (e.g., with adsorbed fluid, liquid media, filled polymers, etc. ), the adsorption properties with respect to polar and nonpolar adsorbates, and other properties important for the practical applications of these materials [1][2][3][4][5][6][7][8][9]. An additional way to change these properties is surface modification of nanoparticles by organic or oganometallic compounds [1][2][3].…”

“…Detailed analysis of the effects of the NPSD, S BET value, and composition of nanoparticles on adsorption of both polar and nonpolar probe adsorbates can be useful for providing a deeper understanding of the interfacial phenomena and the behavior of nanooxides in different practical systems. It is known [2][3][4][5][6][7][8][9][10] that the effective specific surface area (i.e., surface area accessible for given adsorbate molecules) of nanooxides decreases with increasing molecular size of the adsorbates, despite the fact that the primary nanoparticles are nonporous. However, systematic comparative investigations of the adsorption of different nonpolar, weakly polar, and polar probe adsorbates onto composite nanooxides are practically absent in the literature [1][2][3][4][5][6][7][8][9][10][11].…”

“…It is known [2][3][4][5][6][7][8][9][10] that the effective specific surface area (i.e., surface area accessible for given adsorbate molecules) of nanooxides decreases with increasing molecular size of the adsorbates, despite the fact that the primary nanoparticles are nonporous. However, systematic comparative investigations of the adsorption of different nonpolar, weakly polar, and polar probe adsorbates onto composite nanooxides are practically absent in the literature [1][2][3][4][5][6][7][8][9][10][11]. Therefore, the aim of this work was to study the adsorption of nonpolar nitrogen and hexane, weakly polar acetonitrile, and polar diethylamine, triethylamine, and water (the functional groups of which can be representatives for many other compounds) onto individual (silica, alumina, titania) and complex nanooxides such as silica/alumina (SA), silica/titania (ST), and alumina/silica/titania (AST) of different compositions.…”