in this paper, 4,4ʹ-bipyridinium dichloride  supported sba-15 (sba@bipy2+ 2cl-) was used for the synthesis of dihydropyrimidinones. the synthesized catalyst was characterized by ft-ir spectroscopy, scanning electron microscopy (sem), transmission electron microscopy (tem) and thermogravimetric analysis (tga). this nanocomposite was shown to be an efficient heterogeneous catalyst for the synthes...

silica  coated magnetite  nanoparticles were  covalent  grafted with  3-aminopropyl trimethoxysilane  to give aptscmnps. reaction of  the resulted nanomaterial with 4-formyl benzo-12-crown-4 ether afforded fb12c4/aptsmnps  nanocomposite  material  in  which  the  crown ether  moiety  was  attached  through  propyl  chain  spacer. characterization of  the prepared nanocomposite was performed wit...

The purposes of this study were evaluate by energy dispersed X-ray (EDS) and scanning electron microscopy (SEM) the inorganic particles of three nanofilled composite resins, comparing particles sizes, shape and composition, and the filler weight content by thermogravimetric analyzes (TGA). Three composite resins classified as nanofilled were selected to this study: Esthet-X; Grandio; Filtek Sup...

Three azo group-containing Schiff base ligands, namely 1-{3-[(3-hydroxypropylimino) methyl]-4-hydroxyphenylazo}-4-nitrobenzene (2a), 1-{3-[(3-hydroxypropylimino) methyl]-4-hydroxyphenylazo}-2-chloro-4-nitrobenzene (2b) and 1-{3-[(3-hydroxypropylimino) methyl]-4-hydroxyphenylazo}-4-chloro-3-nitrobenzene (2c) were prepared. The ligands were characterized by elemental analysis, FTIR spectroscopy, ...

In this study a special type of silicoaluminophosphate with opal structure (Opal-SAPO) was prepared under microwave condition using tetraethylorthosilicate (TEOS), triethanolamine (TEA), aluminiumisopropoxid and phosphoric acid 85%. The product was characterized by X-ray diffraction (XRD), thermogravimetric (TGA) and Fourier Infrared Spectroscopy (FTIR).The crystalline product showed a good act...

A carbon-based solid acid catalyst (CHACS) derived corncob residual was prepared by incomplete hydrothermal carbonization followed by activation with phosphoric acid impregnation and sulfuric acid sulfonation. The structure of the solid acid catalyst was characterized using Fourier transform infrared spectra (FTIR), thermogravimetric analyzer (TGA), X-ray diffraction (XRD), scanning electron mi...

Hemicellulosic fractions were extracted from soybean hull with various concentrations of NaOH at 50 °C for 5 h. The chemical compositions and physicochemical properties were determined by high performance anion exchange chromatography (HPAEC), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), and C and 2D nuclear magnetic resonance (NMR) analysis. The crystallin...

Biomass materials are being investigated and utilized in an ever-widening sphere of industrial scale applications. As this realm of utilization expands, fundamental knowledge of potential feedstocks becomes paramount. This study was undertaken to observe the chemical composition and thermogravimetric behavior of one set of biomass materials. This set includes fibers or ground portions of: corn ...

In this work, char gasification of two coals (i.e., Shenfu bituminous coal and Zunyi anthracite) and a petroleum coke under a steam and CO2 mixture (steam/CO2 partial pressures, 0.025–0.075 MPa; total pressures, 0.100 MPa) and CO2/steam chemisorption of char samples were conducted in a Thermogravimetric Analyzer (TGA). Two conventional kinetic models exhibited difficulties in exactly fitting th...