PURPOSE This study compared the effect of three intraoral repair systems on the bond strength between composite resin and zirconia core. MATERIALS AND METHODS THIRTY ZIRCONIA SPECIMENS WERE DIVIDED INTO THREE GROUPS ACCORDING TO THE REPAIR METHOD: Group I- CoJet™ Repair System (3M ESPE) [chairside silica coating with 30 µm SiO2 + silanization + adhesive]; Group II- Ceramic Repair System (Ivoc...

An inorganic proton exchange membrane based on sintered mesoporous silica and phosphoric acid was developed with a high proton conductivity of 0.06 S cm(-1) at 200 °C, achieving an excellent power output of 689 mW cm(-2) in H2 at 190 °C and 200 mW cm(-2) in methanol at 200 °C with no external humidification.

The reaction of levulinic acid production from glucose has a stage that requires high temperature and activation energy so in this catalyst is needed. required must have lewis site bronsted the acidity very influential for successful levulonic acid. Silica nickel phosphate catalysts sites Ni metal phosphoric silica groups. was measured using pyridine ammonia adsorption method center strength TG...

The effect of two acids (phosphoric and acetic) and their derivatives (hydrogen di(2-ethylhexyl)orthophosphoric, chloroacetic, dichloroacetic, trichloroacetic, and trifluoroacetic acids) on the retention of selected alkaloids on silica gel plates has been investigated. The dependence of the chromatographic behaviour of the alkaloids on mobile phase diluent and on the concentration of the acids ...

PURPOSE The purpose of this in vitro study was to evaluate the effects of four surface treatments and two resin cements on the repair bond strength of a ceramic primer. MATERIALS AND METHODS Eighty-eight pairs of disks (10 and 5 mm in diameter, 3 mm thickness) were prepared from heat-pressed feldspar ceramics (GC Initial IQ). After being stored in mucin-artificial saliva for 2 weeks, the 10-m...

New modified acidic catalysts were prepared from the treatment of silica, titania and silica prepared from hydrolyzed tetraethyl orthosilicate (TEOS) with sulfuric and phosphoric acid. The sulfated and phosphated silica synthesized from TEOS were calcined at 450 and 650 ◦C. These catalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmissio...