Abstraet--A quantitative method for determination of montmorillonite in the soil clay fraction, using X-ray spectrometry, is proposed. The method is based on the fact that polyvinylpyrrolidone (PVP) is adsorbed on the interlayer surfaces of montmorillonite, giving a first order c-axis spacing of 26/~, while it is not adsorbed on other swelling clays. The experimental conditions to obtain a maxi...

Nano ZnO/ montmorillonite composite were prepared by sol gel method under ultrasonic irradiation from directly mixing montmorillonite nano clay into Zinc gel. The Zn(CH3COO)2.2H2O and montmorillonite nano clay was used as precursor. The zinc acetate was dissolved in DI water and, NH3 (aq) solution was dropped into the zinc solution until pH 9 consequently the zinc gel was produced. The montmori...

The dissolution and swelling properties of montmorillonite at different pH have been studied, using small angle X-ray scattering (SAXS), imaging and osmotic stress methods combined with Monte Carlo simulations. The acidity of montmorillonite dispersions has been varied as well as the counterions to the net negatively charged platelets. At low pH, Na montmorillonite dissolves and among other spe...

[1] We report on laboratory experiments examining the effect of hydration state on the frictional properties of simulated clay and quartz fault gouge. We tested four mixtures of Ca-montmorillonite and quartz (100, 70, 50, and 30% montmorillonite) at four hydration states: dry (<4.50 wt% water), one water interlayer equivalent (4.5–8.7 wt% water), two layers (8.7–16.0 wt% water), and three layer...

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...

Colloidal clay (montmorillonite) strongly inhibited the conjugal transfer of R-plasmid R1drd-19 in Escherichia coli. This finding is discussed in the context of the feasibility of plasmid transfer in environmental waters.

In this study, ZnO/SiO2-clay heterostructures were successfully synthesized by a facile two-step process applied to two types of clays: montmorillonite layered silicate and sepiolite microfibrous clay mineral. In the first step, intermediate silica-organoclay hybrid heterostructures were prepared following a colloidal route based on the controlled hydrolysis of tetramethoxysilane in the presenc...

This review summarizes our recent findings on the role of mineral salts in prebiotic RNA synthesis, which is catalyzed by montmorillonite clay minerals. The clay minerals not only catalyze the synthesis of RNA but also facilitate homochiral selection. Preliminary data of these findings have been presented at the "Horizontal Gene Transfer and the Last Universal Common Ancestor (LUCA)" conference...

-Diffuse Reflectance Fourier Transform Infrared spectroscopy was used to monitor both molecular interactions and concentrations of volatile organic chemicals adsorbed on a commercial montmorillonite. Chemicals tested included propanoic acid, hexanal, heptanal, trimethylamine, dimethylsulfide and dimethyldisulfide. Diffuse Reflectance Fourier Transform Infrared spectroscopy had several advantage...

Montmorillonite, a 2:1 clay mineral, is known to accommodate different organic substances within its interlayer space to form intercalation compounds, which have received much attention because of their stability and physicochemical properties. Its use as a drug carrier is widely studied, as the location of the drug molecules within the interlayer space of the clay may modify the suitability of...