in this research new adsorbents were prepared by modification of surfactant-coated g-alumina with three ligands; 1-(2-pyridylazo)-2-naphtol (pan), dithizone (hdz) and dimetyl golyoxime (dmg). the adsorbents were used for removal and pre-concentration of pb+2, cd+2, ni+2, cu+2, co+2. aqueous solutions of the metal ions were passed through a column filled with the adsorbent and the retained catio...

The effects of (+ )-catechin adsorption to the alumina surface were studied by -potential and surface free energy determination. The presence of catechin causes essential changes in the alumina -potential, which at the concentration slightly higher than 10 M reverses from the positive into negative one. At constant concentration of catechin (10 M), the effect on -potential of alumina as a funct...

This paper presents a part of our work on understanding the effect of nanoscale pore space confinement on ion sorption by mesoporous materials. Acid-base titration experiments were performed on both mesoporous alumina and alumina particles under various ionic strengths. The point of zero charge (PZC) for mesoporous alumina was measured to be approximately 9.1, similar to that for nonmesoporous ...

The synthesis of materials with tailored properties is one of the most active areas of material science [1, 2]. Among so many materials, γ-alumina due to the significant application in catalysis, electronic and ceramic industry has been studied extensively [3]. Various processes have been employed for the preparation of high quality alumina, including sol-gel processing from aluminum alkoxides....

Niobia/alumina model catalysts were prepared by physical vapor deposition of Nb in an oxygen atmosphere onto thin alumina films. Structural characterization, performed with scanning tunneling microscopy and infrared reflection absorption spectroscopy, revealed highly dispersed N2O5 nanoparticles exposing Nb=O groups. Thermal stability of the system was also examined. The results are compared wi...

BACKGROUND The present study aimed to develop an in vitro model for stain removal from natural enamel for the assessment and comparison of oral hygiene products. METHODS Bovine teeth (n = 8 per group) were ground/polished to provide flat enamel specimens and ferric-tannate deposits were precipitated onto the enamel surfaces. The ferric-tannate stained enamel specimens were brushed using an in...

Cracks free mullite-alumina Functionally Gradient Ceramics (FGC) have been obtained by sequential slip casting of Mullite-alumina slurries with diserent mullite/alumina ratios. These slurries were prepared with 65 % solids content and viscosities rangingpom 10 to 40 mPa.s. 7he presence of cracks perpendicular to the FGC layers have been attributed to residual stresses developed because of the m...

Co-synthesis of In2O3 and ZnO nanowires (NWs) were grown on silicon and alumina substrates using vapour transport deposition method. Their morphological structures showed that the NWs were rather aligned on silicon substrate and randomly oriented on alumina substrate. The formation of NWs on silicon substrate was found to be dominated by the growth of ZnO NWs while that on alumina substrate was...