The methods of thermal analysis – thermogravimetry, differential were used to study the catalytic system phosphor-molybdenum heteropoly acid–aluminum oxide. It is shown that modification aluminum oxide has a direct effect on state acid. On surface ƞ-Al2O3, phosphomolybdic acid destroyed by interaction with strong Lewis’s sites carrier, while γ-Al2O3 it retains individuality, probably due multi...

in the present of methylimidazolium hydrogen sulfate, the synthesis of arylidene heterobicyclic pyrimidinones is studied by condensation of aromatic aldehyde, cyclopentanone, and urea or thiourea. using solvent-free conditions, non-toxic and inexpensive materials, simple and clean work-up, short reaction times and good yields of the products are the advantages of this method.

In this article, a series of effective catalysts based on betaine and sulfuric or phosphomolybdic acids was obtained. These compositions were characterized by various physicochemical methods tested in the oxidation sulfur- nitrogenous-containing compounds H2O2. An increase amount heteropolyacid (HPA) leads to non-linear change acidity, degree removal sulfur-containing correlates with concentrat...

The article presents the results of mechanical activation steel-smelting slag affecting properties gypsum composition. As a result study, parameters were identified that characterize reactivity during activation. It was established increase in number Bronsted active adsorption centers on surface formed powders is responsible for their reactivity. However, maximum activity leads to large percent...

Silica Vanadic Acid, SVA, (oxo-vanadium has been supported on silica) as a dual Lewis and Bronsted acid ability was prepared and efficiently catalyzed one-pot multi-component condensation of enolizable ketones or alkyl acetoacetates with aromatic aldehydes, acetonitrile and acetyl chloride. The described reaction was produced β-acetamido ketone or ester derivatives in high to excellent yields i...

In this research, one-pot three-component synthesis of 3,4-dihydropyrimidin-2-(1H)-ones havebeen developed using Biginelli reaction from the interaction between ethyl/methyl acetoacetate,aromatic aldehydes, and urea/thiourea in the presence of 4-sulfobenzoic acid as a new, effective,inexpensive, and available bronsted acid. Avoidance of toxic and dangerous solvents, easy isola...

The history of assessing the acid-base equilibrium and associated disorders is intertwined with the evolution of the definition of an acid. In the 1950s clinical chemists combined the Henderson-Hasselbalch equation and the Bronsted-Lowry definition of an acid to produce the current bicarbonate ion-centred approach to metabolic acid-base disorders. Stewart repackaged pre-1950 ideas of acid-base ...

Two NMR techniques, zH MAS NMR and echo Fourier 27AI NMR, have been applied for the first time to the investigation of Bronsted sites in dehydrated hydrogen forms ofzeolites. The “AI signal of SiOHAl sites, which was “NMR-invisible” until now, yields a quadrupole coupling constant C,,= 16 MHz for the dehydrated zeolite H-ZSM-5. The values of C,, determined from the ZH MAS NMR spectra of SiODAl ...