polyethylene glycol was easily grafted to silica gel and used as a solid–liquid phase transfer catalyst in the reduction of aromatic nitro compounds. this silica-grafted polyethylene glycol is proved to be an efficient heterogeneous catalyst in the reduction of nitroarenes to the corresponding aromatic amines with zinc powder in water. the reduction reactions proceeded efficiently with excellen...

The effects of silica particle addition on the wetting velocity on flat and fractal agar gel surfaces were analyzed along with the applicability of such particles for controlling the wetting dynamics of water. The contact angles (θD) of the colloidal dispersions obeyed the power law, i.e., θD∝t(-x), where t is time and x is a constant. Wetting was inhibited by the addition of a suitable amount ...

The extensive research activity on sol-gel processing of silica glass has been reviewed by several authors [l-4]. The typical alkoxide route to silica sols comprises the catalyzed reaction of tetraethoxysilane (TEOS) and water in a mutual solvent. The TEOS alkoxy groups hydrolyze to form silanol monomers which condense and crosslink to form the silica gel network. The nature of the sol and the ...

A novel nano-hybrid was synthesized through immobilization of amine-functionalized silica gel nanoparticles with nanomagnetite via a co-precipitation technique. The parameters, such as reagent concentrations, reaction temperature and time, were optimized to accomplish the nano-silica gel chelating matrix. The most proper amine-modified silica gel nanoparticles were immobilized with magnetic nan...

A novel tubular device has been developed for hydrogen sulfide determination in air. Several substrates such as commercial silica gel and alumina TLC plates, silica gel powder, alumina, CaSO(4), CaCO(3), BaSO(4), MgO, chalk, alpha-cellulose and ethyl cellulose were tested as solid substrates. 30-70-mesh silica gel was finally employed in glass tubes of 4.0 mm internal diameter. Silica gel is tr...

In the present study, a novel Ni(II) ion-imprinted sulfonate functionalized silica gel polymer was prepared with the surface imprinting technique by using nickel(II) as the template ion, grafted silica gel as the support, and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and ethylene glycol dimethacrylate (EGDMA) as the functional monomer and crosslinker, respectively. The sorbent was cha...

The reactive tissue response of the brain to chronically implanted materials remains a formidable obstacle to stable recording from implanted microelectrodes. One approach to mitigate this response is to apply a bioactive coating in the form of an ultra-porous silica sol-gel, which can be engineered to improve biocompatibility and to enable local drug delivery. The first step in establishing th...