Adsorption-desorption of the herbicide glyphosate (GPS) onto the clay mineral montmorillonite has been studied in presence of copper, in order to clarify the effects that this strongly complexing metal could have on the availability and mobility of GPS in soil environment. In contrast with previous findings, GPS adsorption on montmorillonite decreases in the presence of Cu, in solution or adsor...

The transport of colloid in unsaturated porous media affects the migration contaminants and thus is closely related to groundwater resources protection. To figure out combined effects grain size, concentration injection flow rate on montmorillonite characteristics quartz sand, a total 27 sets column experiments were conducted with three kinds sand (20, 40, 60 mesh), rates (1.98, 3.96, 5.94 cm 3...

Background: Ramsar, a northern city in Iran, lies on the coast of the Caspian Sea. This city has areas with some of the highest levels of natural radiation measured to date. The radon concentration in some areas of Ramsar is up to 3700 Bq m–3. On the other hand, due to high level of humidity, damp-proof barriers should be used in construction of new buildings in radon prone areas of this cit...

Our continuing research on the preparation, characterization, materials properties, and biodegradability of polylactide (PLA)/organically modified layered silicate (OMLS) nanocomposites has yielded results on PLA/montmorillonite nanocomposites. Montmorillonite (mmt) modified with dimethyldioctadecylammonium cation was used as an OMLS for nanocomposite preparation. The internal structure of nano...

the aim of this study was to investigate the rate of water vapor permeability (wvp) and moisture sorption of starch-montmorillonite (mmt) nanocomposite films. the nanocomposite films were prepared using the casting method andglycerol was used as a plasticizer. the effect of glycerol concentration on wvp of the films was determined at 25°c with a relative humidity of 0-99% (inside and outside of...

-A glass in the intermediate composition of montmorillonite and beidellite, 50/50 in mole ratio, was treated under a hydrothermal pressure of 100 MPa, in the temperature range from 250 to 500~ and durations from 2 to 129 days. The phases identified in the products were plotted in a time-temperaturetransformation (TTT) diagram. The TTT diagram showed that the regularly interstratified montmorill...

STUDY OF CONTROLLED RELEASE OF DAPSONE FROM MODIFIED MONTMORILLONITE AND POLYMER MATRICES

The hydraulic conductivity of diverse organoclays was determined through percolation experiments and compared to a raw Na-montmorillonite (Na-Mt). incorporation surfactants even at low content drastically changes the with large increase about two order magnitude in contrast that Na-Mt (10?12 m s?1). Batch kinetics equilibrium adsorption confirmed proper affinity zwitterion antibiotic: amoxicill...

This study was conducted to investigate organoclay prepared using montmorillonite clay with zinc oxide (ZnO) nanoparticles and a long-chain organic surfactant hexadecyltrimethylammonium bromide for the removal of nitrate ion from aqueous solutions. Adsorbents were evaluated by X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FT-IR),...

The nature of surface complexes formed on Ni uptake onto montmorillonite (a dioctahedral smectite) has been investigated over an extended time period by polarized extended X-ray absorption fine structure (P-EXAFS) spectroscopy. Self-supporting films of Ni-sorbed montmorillonite were prepared by contacting Ni and montmorillonite at pH 7.2, high ionic strength (0.3 M NaClO4), and low Ni concentra...