A direct alkaline hydrothermal method was used to synthesize mono- and bimetallic Ni Cu on mesoporous silica (m-SiO2) as catalysts for the hydrogenation of furfural (FAL) cyclopentanone (CPO). The were characterized by XRD, FTIR, H2-TPR, SEM, TEM, HR-TEM, XPS, ICP, BET, CHN analysis. results demonstrate that addition metal improved reducibility revealed Ni-Cu alloy formation over m-SiO2. Furthe...

The largest industrial application of olefin metathesis today is the synthesis of propylene from ethylene and butenes employing WO3 on SiO2, a relatively long-lived and regenerable catalyst that operates at 350–400 °C. It is widely proposed that high temperatures are required because the percentage of metal sites actually involved in the metathesis reaction is extremely low, or the reaction tha...

A convergent [3+2] block synthetic strategy was developed for the synthesis of the pentasaccharide repeating unit of the cell wall O-antigen of Escherichia coli O11 strain in excellent yield in a minimum number of steps. Several suitably functionalized thioglycoside derivatives were used as glycosyl donors during the synthesis of the target compound. A thioglycoside was the glycosyl donor used ...

In this research the magnetite nanoparticles supported silica sulfonic acid(Fe3O4@SiO2@OSO3H) was used as a green and efficient catalyst for the preparation ofoctahydroquinazolinone derivatives as biologically active heterocyclic compounds. Thisprocedure avoids hazardous reagents, solvents, catalyst and can be an eco-friendly alternativeto the existing methods. The one-p...

The purpose of the present study is to evaluate the fracture load of composite-based repairs to fractured zirconium oxide (Z) crowns and to ceramic-fused-to-metal (CM) crowns, comparing different mechanical surface preparation methods. A total of 75 crowns were repaired; samples then underwent dynamic loading and thermocycling. Final fracture load values for failure of the repaired crowns were ...

An analytical method using silica supported silver nanoparticles as a novel sorbent for the enrichment and determination of inorganic mercury (iHg) in surface water samples has been developed. Silver nanoparticles (AgNPs) were synthesized by a completely green procedure and were deposited onto the amine functionalized surface of silica submicrospheres (SiO2-NH2). The prepared nanocomposite mate...

In this work, Fe3O4@SiO2 nanoparticles were coated with mesoporous silica shell by S-N+I- pathway by using anionic surfactant (S-) and co-structure directing agent (N+). The role of co-structure directing agent (CSDA) is to assist the electrostatic interaction between negatively charged silica layers and the negatively charged surfactant molecules. Prior to the mesoporous shell formation step, ...

Elevated temperature synthesis has been used to generate virtually defect free SiO2 sheathed crystalline silicon nanowires and silica (SiO2) nanospheres which can be agglomerated to wire-like configurations impregnated with crystalline silicon. The SiO2 passivated ~sheathed! crystalline silicon nanowires, generated with a modified approach using a heated Si–SiO2 mix, with their axes parallel to...