The synthesis of thioethers starting from alcohols and thiols in the presence of amorphous solid acid catalysts is reported. A silica alumina catalyst with a very low content in alumina gave excellent results in terms of both activity and selectivity also under solvent-free conditions. The reaction rate follows the electron density of the carbinol atom in the substrate alcohol and yields up to ...

Al2O3:SiOC nanocomposites were synthesized by thermal treatment of fumed alumina nanoparticles modified by phenyltrimethoxysilane. The effect of annealing temperature in inert ambient on structure and photoluminescence of modified alumina powder was studied by IR spectroscopy as well as photoluminescence spectroscopy with ultraviolet and X-ray excitation. It is demonstrated that increase of ann...

H3PW12O40 (PW12) was immobilized over mesoporous alumina through the reaction of mesoporous alumina functionalized 3-aminopropyl triethoxy silane (3-APTES) and PW12. The surface properties of the functionalized nanocomposite was analyzed by a series of characterization techniques like elemental analysis, FTIR and XRD. XRD and adsorption–desorption analysis shows that the mesostructure of silica...

In this study, different nanofluids with phase change behavior were developed by mixing a molten salt base fluid (selected as phase change material) with nanoparticles using the direct-synthesis method. The thermal properties of the nanofluids obtained were investigated. These nanofluids can be used in concentrating solar plants with a reduction of storage material if an improvement in the spec...

to either aluminum ions or surface hydroxyls and can result in the formation of a surface alkoxide. The properties of inorganic membranes are dependent on the The purpose of this note is to illustrate the effects of heat treatment and surface chemistry of the material, which in turn are affected by chemisorption of organic molecules on the permeability characteristics of parameters such as temp...

Excess electrons in solvent are amongst the most fascinating chemical species, at the very edge between physics and chemistry. In this contribution, we report the use of silica and alumina photochemistry to create and stabilize aqueous solutions of electron.

Time-resolved near-IR phosphorescence spectroscopy was employed to determine the lifetime of singlet oxygen in Y-zeolites and porous silica and it was found to depend strongly on the alumina content of the zeolite.

Studies were conducted to determine the effects of a panel of seven nanomaterials (NMs), namely: α-alumina, γ-alumina, precipitated silica; silica fume, calcined silica fume, colloidal antimony pentoxide (Sb(2)O(5)), and superfine amorphous ferric oxide (Fe(2)O(3)), on sediment dwelling invertebrates Chironomus tentans under controlled laboratory conditions. Percentage survival, enzyme activiti...

Synthetic mesoporous alumina and silica minerals with uniform pore geometries, and their nonporous analogues, were used to test the role of mineral mesopores (2-50 nm diameter) in protecting organic matter from enzymatic degradation in soils and sediments. Dihydroxyphenylalanine (L-DOPA), a model humic compound, was irreversibly sorbed to both mineral types. The surface area-normalized adsorpti...

Until the arrival of the theories of plate tectonics and seafloor spreading in the 1960s, the Earth’s mantle was generally believed to consist of peridotites of uniform composition. This view was shared by geophysicists, petrologists, and geochemists alike, and it served to characterize the compositions and physical properties of mantle and crust as “Sial” (silica-alumina) of low density and “S...