The methodology involves preparing polyvinyl sulfuric acid as a solid acid by simple mixing ofpolyvinyl alcohol with chlorosulfonic acid in CH2Cl2 at room temperature. The catalytic ability ofthe solid acid was investigated for the facile conversion of benzylic alcohols to the unsymmetricalethers with aliphatic alcohols in the presence of the solid acid. Results show that the solid acid isan ap...

this study is focused on synthesis of nano-colloidal silica via alkaline water glass solution. sodium ions of water glass were removed by cation exchanging in a resin column to obtain the silicic acid which was titrated to the solution of sodium silicate. concentration of the colloidal silica and ph value of the solutions were controlled using different concentrations of alkaline sodium silicat...

knoevenagel condensation between barbituric acid and aldehyde was investigated in the presence of sulfonic acid functionalized nanoporous silica (sba-pr-so3h) and resulted in the formation of arylidene and bis-arylidene barbiturates. excellent yields and short reaction times are related to the high efficiency of sba-pr-so3h that the reactions take place easily in its nano-pores. sba-pr-so3h as ...

The synthesis of polymer brush decorated silica nano-particles is demonstrated by activator regeneration by electron transfer atom transfer radical polymerization (ARGET ATRP) grafting of poly(tert-butyl methacrylate). ATRP initiator decorated silica nano-particles were obtained using a novel trimethylsiloxane derivatised ATRP initiator obtained by click chemistry. Comparison of de-grafted poly...

introduction conventional water treatment consist of unit processes include coagulation, flocculation, clarification, filtration and disinfection that goal is removal of turbidity, color and certain bacterial species. in filtration process flocculated substances that have not removed in pervious stage are sediment. filter media is often silica sand that removal mechanism is complex and consists...

A novel Congo red (CR) derivatized silica stationary phase was prepared and packed into a fused silica capillary tube for nano-flow HPLC. A variety of analytes including poly-aromatic hydrocarbons, parabens, acids, sulfonamides, bases, and nucleosides were successfully separated using the CR. In comparison with commercial ODS columns, this new stationary phase has a different separation mechani...

The nano-sized silica fillers reinforced poly(ether ether ketone) (PEEK) composites were fabricated by means of compression molding technique. he nano-sized silica, measuring 30 nm in size, was firstly modified by surface pretreatment with stearic acid. The performances and properties f the resulting PEEK/SiO2 nanocomposites were examined in terms of tensile loading, hardness, dynamic mechanica...

two simple protocols for the synthesis of tetrahydrobenzo[a]xanthenes-11-ones using nano silica phosphoric acid are reported. short reaction times, high yields, reusability of catalyst and easy workup are some advantages of these protocols.

This study is focused on synthesis of nano-colloidal silica via alkaline water glass solution. Sodium ions of water glass were removed by cation exchanging in a resin column to obtain the silicic acid which was titrated to the solution of sodium silicate. Concentration of the colloidal silica and pH value of the solutions were controlled using different concentrations of alkaline sodium silicat...