The results of the effects of electrolyte type and concentration, nanoparticle concentration, pH, and temperature on the mobility and aqueous stability of polyethylene glycol (PEG)-coated silica nanoparticles are presented. Nanoparticle mobility was evaluated based on the ability to inhibit montmorillonite swelling in aqueous solutions through visual swelling tests, and the results were quantif...

The aim of this study was to investigate the effects of graded levels of montmorillonite, a constituent of clay, on performance, hematological parameters and bone mineralization in weaned pigs. One hundred and twenty, 35-d-old crossbred pigs (Duroc×Large White×Landrace, 10.50±1.20 kg) were used in a 28-d experiment and fed either an unsupplemented corn-soybean meal basal diet or similar diets s...

Antibiotic ciprofloxacin (CIP) is immobile in the subsurface but it has been frequently detected in the aquatic system. Therefore it is important to investigate the factors impacting CIP's mobilization in aquifer. Laboratory columns packed with sand were used to test colloid-facilitated CIP transport by 1) using kaolinite or montmorillonite to mobilize presorbed-CIP in a column or 2) co-transpo...

Land use change results in soil migration into aquatic streams during storm events. This suspended sediment, even in the absence of adsorbed contaminants, may be a significant stressor to aquatic organisms. In some parts of the US, total suspended solids (TSS) concentrations surpass 100,000 mg/L during storm events. The limited data on effects of suspended sediment concentrations on freshwater ...

Soil surface electrochemical properties may have a strong influence on nitrifying microorganisms, Hþ and NH4 þ activities, and therefore on the nitrification process. A gradient of surface electrochemical parameters was obtained by amendment of a subtropical acid pine soil (Oxisol) with 0% (control), 3%, 5%, 8%, 10% and 12% pure Ca-Montmorillonite by weight. The Hþ and NH4þ activities, the abun...

The influence of humic acid (HA) on Ni(II) sorption to Ca-montmorillonite was examined by using a combination of batch sorption experiments and extended X-ray absorption fine structure (EXAFS) spectroscopy technique. The sorption of Ni(II) on HA-montmorillonite hybrids is strongly dependent on pH and temperature. At low pH, the sorption of Ni(II) is mainly dominated by Ni-HA-montmorillonite and...

A magnesium hydroxide-montmorillonite complex prepared at an OH/Mg molar ratio of 2 (16 meq Mg/g clay) and immediately cleaned of any free Mg(OH)2 behaves like magnesium-chlorite and shows no change during 3 months ageing. Magnesium hydroxide completely precipitates within the interlayer space of montmorillonite. X-ray diffraction analysis, thermal (DTA and TGA) studies, i.r. absorption analysi...

A quantitative description of specific ion effects is an essential and focused topic in colloidal and biological science. In this work, the dynamic light scattering technique was employed to study the aggregation kinetics of colloidal particles in the various alkali ion solutions with a wide range of concentrations. It indicated that the activation energies could be used to quantitatively chara...

BACKGROUND Metalloporphyrin ions, with planar shape, have been known to intercalate horizontally and diagonally between montmorillonite layers. Perpendicular intercalation inside montmorillonite has not been reported earlier. This work aims at achieving perpendicular intercalation inside montmorillonite in natural clays. Possible intercalation inside other forms of natural clay will also be inv...