a novel nano – sized  manganese (ii) coordination polymer, [{mn(ncs)2(l)(h2o)2}(l)]n  , (1) (l- = 4,4'-bipyridine), have been synthesized by a sonochemical process and characterized by scanning electron microscopy (sem), x-ray diffraction (xrd), ir spectroscopy and elemental analysis.  direct calcination of the single crystals and nano-sized compound 1 at 400 0c under air atmosphere yields...

The interaction of vanadium oxide and niobium oxide with A1203 and TiO2 supports is examined with Raman spectroscopy. The Raman spectra of the supported metal oxides reveal that the strong interaction of the metal oxides with AI203 and TiO2 supports results in the formation of two-dimensional surface metal oxide overlayers. The surface vanadium oxide overlayers are unstable to high calcination ...

A one-dimensional mathematical model was developed for the simulation of limestone calcination in rotary kilns. The model is comprised of ordinary differential equations derived from mass and energy conservation principles. The system of equations is solved by a fourth-order Runge-Kutta method. The model predicts, in the axial direction, temperature profiles for the bed of particles, the gas ph...

Mesostructured nickel oxide was formed with nickel sulfate and cationic surfactant cetyltrimethylammonium bromide (CTAB). X-ray diffraction (XRD) peaks at low scattering angles and transmission electron microscopy (TEM) indicated that a mesostructure was formed. However, these XRD patterns disappeared after calcination. The addition of sodium silicate in the precursor solutions produced a mesos...

Nanostructured alumina thin films were coated on stainless steel by Sol-Gel dip coating method. In order to prevent crack formation, Al2O3 films were kept in a solvent bath immediately after coating to reduce the rate of drying. Effects of calcination temperature and withdrawal speed on structural properties were analyzed using XRD and SEM. Topography and thickness of coat...

in this research, a sol gel autocaombustion route has been proposedto synthesize alumina-zirconia composite powders, usingammonium bicarbonate as a new fuel. then the effect of calcinationtemperature on phase transformation and crystallite sizes wasinvestigated. to characterize the products xrd, tem and betanalyses were used. xrd patterns of as-synthesized powder andcalcined powders at 1100 ◦c ...

quantitative determination of br?nsted acid sites in acidic mordenite samples with varying proton concentrations has been studied using aqueous conductometric titration method. conductometric titration of the ammonium form of mordenite with sodium hydroxide is feasible and the results indicate potential number of br?nsted acid sites. however, br?nsted acid sites concentration in acidic mordenit...

The presence of elevated concentration of arsenic in water sources is considered to be health hazard globally. Calcination process is known to change the surface efficacy of the adsorbent. In current study, five adsorbent composites: uncalcined and calcined Fe3O4-HBC prepared at different temperatures (400°C and 1000°C) and environment (air and nitrogen) were investigated for the adsorptive rem...

Zirconia-supported tungsten oxide (WO(x)/ZrO(2)) is considered an important supported metal oxide model acid catalyst, for which structure-property relationships have been studied for numerous acid-catalyzed reactions. The catalytic activity for xylene isomerization, alcohol dehydration, and aromatic acylation follows a volcano-shape dependence on tungsten surface density. However, WO(x)/ZrO(2)...