Recent approaches used to characterize the elastic or viscoelastic properties of materials with nanoscale resolution have focused on the contact resonances of atomic force microscope (CR-AFM) probes. The experiments for these CR-AFM methods involve measurement of several contact resonances from which the resonant frequency and peak width are found. The contact resonance values are then compared...

By regarding the complex indicatrix as an embedded CR-hypersurface of the holomorphic tangent bundle in a fixed point, we analyze some aspects of the relations between its CR structure and the considered contact structure. Moreover, using the classification of the almost contact metric structures associated with a strongly pseudo-convex CRstructure, of D. Chinea and C. Gonzales, we determine th...

The current study both synthesizes and uses four compounds of graphene oxide (GO), nitrogen doped graphene oxide (ND-GO), high nitrogen doped graphene oxide (HND-GO), and three dimensional high nitrogen doped graphene oxide (3D-HND-GO) in order to remove a model anionic dye, Congo red (CR) from wastewaters. It also compares their carbon nano-structure, with regard to removal efficiency and find...

We study the spreading of excitations in 2D systems of mobile agents where the excitation is transmitted when a quiescent agent keeps contact with an excited one during a nonvanishing time. We show that the steady states strongly depend on the spatial agent dynamics. Moreover, the coupling between exposition time (omega) and agent-agent contact rate (CR) becomes crucial to understand the excita...

Background & Aims of the Study: Since the chromium (VI) is a toxic, carcinogenic and non-biodegradable element and can accumulate in the tissues, the presence and release of this element through the effluents is associated with dangerous effects on life cycle. Thus, it should be removed from the effluents. In the present study, biosorption of Cr(VI) from aqueous solutio...

Adsorption capacity of Cr (VI) onto sawdust of aspen tree and activated sawdust, was investigated in a batch system by considering the effects of various parameters like contact time, initial concentration, pH , temperature, agitation speed, absorbent dose and particle size. Cr (VI) removal is pH dependent and caused to be maximum at pH 2.0. The amounts of Cr(VI) adsorbed increased with increas...

The present work was conducted for the synthesis of nano size zerovalent iron (nZVI) and hexavalent chromium (Cr(VI)) removal as a highly toxic pollutant by using this nanoparticles. Batch experiments were performed to investigate the effects of Cr(VI), nZVI concentration, pH of solution and contact time variation on the removal efficiency of Cr(VI). nZVI was synthesized by reduction of ferric ...

The aim of this study was to evaluate the efficiency of nano-sized cellulose obtained from rice husk for Cr(VI) adsorption. The effect of operational parameters including initial pH (3-10), contact time (0-120 min), adsorbent dosage (0.2-1.5 g/L), and initial Cr(VI) concentration (5-50 mg/L) were investigated according to one factor at time method. The results showed, in pH=6, contact time=100 ...