Nano silica sulfuric acid as a solid acid, was described to be an effective catalyst for one-pot three-component reaction of kojic acid, aryl aldehydes and indoles for the preparation of 2-substituted aryl (indolyl) kojic acid derivatives. The catalyst was prepared by combination of chlorosulfonic acid to nano silica gel. The size of nanoparticles were observed with SEM.All prepared compounds w...

in this study, different contents of nano-silica, 2 wt.%, 4 wt.% and 6 wt.%, have been added to bitumen tomodify the physical, mechanical and rheological properties of warm mix asphalt (wma). wma iscontaining 2 wt.% of sasobit (mixture of long-chain hydrocarbons). various quality control tests have beencarried out to characterize the modified bitumen and wma. the rheological investigations show...

N-sulfonic acid pyridinium -4-carboxylic acid chloride {[Pyridine-N-SO3H-4-COOH]Cl} was synthesized, identified and applied as an effective catalyst for the preparation of pyrido[2,3-d:6,5-d]dipyrimidines by the condensation reaction of various aldehyde with 2-thiobarbituric acid and ammonium acetate under solvent-free conditions.The structure ofcatalyst was studied...

bifunctional acidic ionic liquids, having both h-imidazolium and -so3h groups as cation moieties (h-bfails) and cf3so3- as anion, were synthesized in high yields. these h-bfails showed significant hydrophilic properties, lower acidity and higher thermal stability relative to common ionic liquids, due to their unique structures. the (propyl or butyl-3-sulfonic) imidazolium trifluoromethane sulfo...

A novel method of preparing the macrporous nickel coating was described. The macrporous nickel coating was fabricated by employing nano-silica as the template. The effects of technological conditions and the concentration of the additives on the surface quality of coating were investigated, the nano-silica was characterized transmission electron microscopy (TEM) and laser particle size analyzer...

Mesoporous MCM-41 was coated on Fe3O4 nanoparticles and then functionalized with sulfurochloridic acid to provide a core-shell solid acid nano-catalyst. The catalyst was characterized by transmission electron microscopy (TEM), infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TG), Brunauer-Emmet-Teller analysis (BET) and vibrating sample magnetometery (VSM). The...

OBJECTIVE The purpose of this study was to evaluate the hardness of the adhesive interface between resin and Er:YAG laser-irradiated bovine dentin by nano-indentation. BACKGROUND DATA It has been reported that laser output energy and pulse repetition rate affect the tensile bond strength in Er:YAG laser-irradiated dentin. MATERIALS AND METHODS Three laser settings were evaluated at the same...

Improving the mechanical properties of epoxy-based adhesives with nanoparticles is one methods which justifies use adhesive joints significantly. This work studies strength adhesively bonded single-lap (SLJs) considering pure adhesive, reinforced nano-silica particles (NSPs), nano-clay (NCPs), and a combination both nano particles. Uniaxial tensile testing SLJs was conducted to reveal failure l...

A nano-composite powder composed of silica and carbon with a unique property could be prepared from a mixture of a silicate compound and an epoxy compound, in which the silica within the nano-composite powder has a BET surface area of as high as greater than 800m2/g although the nano-composite powder has a BET surface area of less than 10m2/g. It was estimated that the silica and the carbon are...