Sulfated zirconia (SZ) and sulfated zirconia promoted with 2 wt % manganese (MnSZ) or iron (FeSZ), all active in n-butane isomerization, were investigated using diffuse reflectance Fourier transform IR spectroscopy (DRIFTS). By adsorption of H(2) at 77 K or of n-butane at room temperature, it was found that the promoters neither enhance the Lewis nor the Brønsted acid strength. SZ and promoted ...

The ideal gasoline must have a high pump octane number, in the 86 to 94 range, and a low environmental impact. Alkanes, as a family, have much lower photochemical reactivities than aromatics or olefins, but only the highly branched alkanes have adequate octane numbers. The purpose of this work is to examine the possibilities of extending the technological alternative of paraffin isomerization t...

Shape and size of the synthesized NiO nano-sheets were retained during transformation of sheet-like b-Ni(OH)2 to NiO at elevated temperatures via nano-sized zirconia coating on the surface of b-Ni(OH)2. The average grain size was 6.42 nm after 600 C treatment and slightly increased to 10 nm after 1000 C treatment, showing effective sintering retardation between NiO nano-sheets. The excellent th...

Abstract: Solid acid (heterogeneous) catalysts have a unique advantage in esterifi cation and transesterifi cation reactions which enhances the use of high acid value oil to be used as feedstock for synthesis of biodiesel. Various solid acid catalysts such as resins, tungstated and sulfated zirconia, polyaniline sulfate, heteropolyacid, metal complexes, sulfated tin oxide, zeolite, acidic ionic...

PURPOSE The purpose of this study was to evaluate the effect of nano-structured alumina surface coating on shear bond strength between Y-TZP ceramic and various dual-cured resin cements. MATERIALS AND METHODS A total of 90 disk-shaped zirconia specimens (HASS CO., Gangneung, Korea) were divided into three groups by surface treatment method: (1) airborne particle abrasion, (2) tribochemicalsil...

Degradation of yttria-stabilized zirconia dental implants abutments due to the tetragonal to monoclinic phase transformation was studied in detail by microstructural characterization using Electron Back Scatter Diffraction (EBSD). The amount and distribution of the monoclinic phase, the grain-size distribution and crystallographic orientations between tetragonal and monoclinic crystals in 3 mol...

Spray drying is widely used for producing granulated feed materials for compaction process, which is the current industrial method for manufacturing alumina-zirconia femoral heads. The optimization of the granules compaction behavior requires the control of the slurry rheology. Moreover, for a dual-phase ceramic suspension, the even phase distribution has to be kept through the atomization step...

β -Acetamido ketones are valuable building blocks for the preparation of β -amino ketones or β -amino alcohols such as the antibiotic nikkomycins [1] and neopolyoxines [2]. α-Acetamido ketones are obtained in the Dakin-West reaction [3] and β -acetamido ketones by the Iqbal route. In the latter, an aromatic aldehyde, an enolizable ketone and acetonitrile are condensed in the presence of acetyl ...