In Pt/ZrO2 catalysts used for CO2/CH4 reforming to syngas, not all accessible Pt contributes equally to the activity of the catalyst. The catalytic activity is determined by the accessibility of Pt on the Pt-ZrO2 perimeter. This is explained in terms of the CO2 activation via carbonate species on the support which must be in the proximity of the Pt particles to react with the methane activated ...

Nanostructurally stabilized zirconium oxide (NSZ) hard transparent fi lms were produced without chemical stabilizers by the ion beam assisted deposition technique (IBAD). A transmission electron microscopy study of the samples produced below 150 °C revealed that these fi lms are composed of zirconium oxide (ZrO2) nanocrystallites of diameters 7.5 ± 2.3 nm. X-ray and selected-area electron diffr...

Polymer-clay nano-composite materials, in which nano-meter thick layers of clay dispersed in polymer matrix, have generally higher mechanical properties than normal polymeric materials. A new three-dimensional unit cell model has been developed for modeling three constituent phases including inclusion, interphase and matrix. The total elastic modulus of nano-composite is evaluated.  Numerical r...

Thin ZrO2 films were produced at 323K by deposition of colloids from stable, aqueous dispersions (formed from 4mM Zr(SO4)2 in 0.4N HCl) onto silicon wafer-supported, functionalized self-assembled monolayers (SAMs). Deposition took place without visible bulk precipitation. As-deposited and heat-treated films were characterized by high-resolution transmission electron, analytical electron and sca...

Tungstated zirconia (WO3/ZrO2) is one of the most well-studied solid acid catalyst systems and continues to attract the attention of both academia and industry. Understanding and controlling the properties of WO3/ZrO2 catalysts has been a topic of considerable interest over almost the past three decades, with a particular focus on discovering the relationship between catalytic activity and the ...

In order to investigate the control mechanism of composite phase change materials (PCM), a series nano-phase emulsion (NPCE) were prepared in this paper with high thermal conductivity, heat storage and low supercooling using hexadecane, octadecane, hexadecanol, octadecanol various metal nano-particles. Through mechanism, it is expected adjust transition range NPCE desirable range. The NPCEs cha...

A series of TiO2-ZrO2/SiO2 nanocomposites were synthesized using a liquid-phase method and characterized by various techniques, namely, nitrogen adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, high-resolution transmission electron microscopy, and photon correlation spectroscopy (PCS). It was revealed that the component ratio and calcin...

Solvent-free technique was employed in this work in order to assess the influence of the calcination temperature on the activity of Al-promoted sulfated zirconia. The catalyst was analyzed by XRD and IR-spectrum method, and catalytic activity was examined by esterification reaction of oleic acid. XRD analysis revealed that a decline in the percentage of tetragonal phases of zirconia was observe...

Oxidative dehydrogenation (ODH) of propane was studied on zirconia-supported molybdenum oxide catalysts. The structure of the ZrO2 support and of the dispersed MoOx species was characterized by X-ray diffraction and by Raman and UV–visible spectroscopies. The structure of dispersed molybdena depends on the Mo surface density and on the temperature at which catalyst precursors are treated in air...

The influences of nano-ZrO2 (NZ), nano-TiO2 (NT), nano-Fe2O3 (NF) and nano-Al2O3 (NA) additions on properties of the fresh and hardened cement paste in comparison with the fine cement paste were experimentally studied. Mini slump and flow cone tests were conducted on fresh cement pastes. Moreover the compressive and tensile strength of hardened cement paste were measured. SEM micrographs and XR...