a novel rice-husk-silica supported n-propyl bipyridinium chloride (rhprbpcl) has been prepared. due to the basicity of rhprbpcl, it was decided to evaluate its catalytic activity in the one-pot preparation of tetrahydrobenzo[b]pyran, dihydropyrano[3,2-c]chromene and dihydropyrano[4,3-b]pyran derivatives. the catalyst was characterized by ft-ir, sem and tga analyses. this methodology offers seve...

Palladium nanoparticles were captured onto spherical silica particles using a molecular band composed of imidazolium chloride and urea moieties to form raspberry-like Pd@SiO2 composites, which can be recovered and reused without any loss of catalytic activity in Suzuki-Miyaura coupling.

Cage-like ordered mesoporous silica, FDU-1, with about twice the pore volume and a narrower pore size distribution compared with those for previously reported samples was synthesized in a much shorter time by doubling the amount of block copolymer, adding sodium chloride and lowering the acid concentration.

Methylenecyclopropylcarbinols treated with sulfonyl chloride and Et(3)N form the sulfonated products in almost quantitative yields, which can be transformed to the corresponding 3-methylenecyclobutyl sulfonates with silica gel chromatography work-up. The rational explanation was proposed on the basis of computational studies.

In the past, helical shapes in nature have inspired inventions such as the water screw for agriculture, the retaining screw for wine presses, and architectural designs for spiral staircases. Similarly, these days helix-shaped DNA, proteins and carbon nanotubes evoke great interest in biotechnology and nanotechnology. Also biomimetic synthesis of helical morphologies of calcium carbonate, barium...

Infiltration and defiltration behaviors of liquids modified by potassium chloride and ethylene glycol in a nanoporous silica are investigated through a high-pressure experiment. At the first loading, infiltration can always take place quite smoothly no matter how viscous the liquid is. The infiltration pressure can be well described by linear superposition of the contributions of liquid compone...

We describe the use of one of the most advanced radical polymerization techniques, the reversible addition fragmentation chain transfer (RAFT) process, to produce highly functional core-shell particles based on a silica core and a shell made of functional polymeric chains with very well controlled structure. The versatility of RAFT polymerization is illustrated by the control of the polymerizat...

A simple preparation process of alkylamide phase for reversed-phase HPLC (RP-HPLC) is described. The process includes aminopropyltrimethoxysilane firstly reacted with octanoyl chloride, then the intermediate was coupled onto porous silica. The resultant bonded silica has a reproducible ligand surface concentration and homogenous bonded ligand distribution on the porous silica. Characterization ...

Multifunctional silica nano-vehicles (SiO2@indol-IL) and magnetic nanoparticles (Fe3O4@indol-IL) were constructed through the Schiff bases condensation of indole-3-carboxaldehyde and 4-acetyl-N-allyl pyridinium chloride (ILs) with the amine groups of silica and magnetic nanoparticles. SiO2@indol-IL can inhibit the proliferation of HepG-2 cells in 48 h. Fe3O4@indol-IL can mimic the function of c...

We compare the methods of continuous solvent (Soxhlet) and supercritical solvent extractions for the removal of the organic template from nanostructured silica monoliths. Our monoliths are formed by templating the L3 liquid crystal phase of cetylpyridinium chloride in aqueous solutions with tetramethoxy silane. The monoliths that result from both Soxhlet and supercritical extraction methods are...