Because methyl bromide (CH3Br) is a widely used agricultural fumigant for soil disinfection, it is important to know the chemical behavior and fate of CH3Br as a result of its use for soil treatment. A solid-state 13C NMR study of 13CH3Br-treated soil and soil-component samples shows that methylation of soil organic matter may be the major pathway for degradation of CH3Br in soils. Adsorption o...

Abstraet--Jordanian natural kaolin and bentonite show good catalytic activity towards debutylating 2tert-butylphenol, and varying debutylation vs. isomerization selectivity after acid activation. The resulting catalytic activity of these samples is dependent on the acid employed for activation; the samples treated with acetic acid showed relatively low conversions, whereas those treated with hy...

Wind erosion is a widespread phenomenon in arid region. The purpose of this study was assessed the capacity of nanoclay to control soil erosion in wind tunnel experiment. The nanoclay isolated from soils was dominant in montmorillonite. A sandy soil from the Khara desert, nearly 100 km East of Isfahan (Central Iran) was used. The soils of this area are structurally unstable and sandy texture ma...

We have characterized a montmorillonite-based organoclay dispersed in three different nonaqueous solvents using a combination of x-ray scattering, small-angle neutron scattering (SANS), and ultrasmall angle neutron scattering (USANS), together with rheological measurements. Consistent with these measurements, we present a structural model for the incompletely dispersed clay as consisting of ran...

Effects of montmorillonite and barium titanate nanofillers V. Tomer, G. Polizos, E. Manias, and C. A. Randall Department of Materials Science and Engineering, Materials Research Laboratory, Center of Dielectric Studies (CDS), The Pennsylvania State University, University Park, Pennsylvania 16802, USA Department of Materials Science and Engineering, Polymer Nanostructures Laboratory, Center for ...

Aqueous suspensions of exfoliated Li0 .25MoO 3 and Na-montmorillonite have been combined and dried to form interstratified solids. X-ray diffraction patterns of ethylene glycol treated films show that the d-spacing of restacked materials varies with composition between the limits established by the two end members. Based on these data, we conclude that the new materials are composed of individu...

Porous clay heterostructures (PCH) based on modified montmorillonite were synthesized using different reaction conditions (different hydration degrees, pH values and reaction times). The PCH precursors and PCH were characterized using FTIR Spectroscopy and X-Ray Diffractions (XRD). The XRD results showed that basal distance of porous clay heterostructures was significantly influenced by the mod...

Base-exchange determinations were made on selected clays of the montmorill0niteillite group to test this method as an analytical tool for the analysis of mixed-layer aggregates. The relatively rapid manganese method developed by Bower and Truog was used and its precision determined oll monodisperse, monomineralic fractions and monodisperse fractions of prepared mixtures of illite and montmorill...

Cesium adsorption on the clay minerals vermiculite and montmorillonite is described as a function of surface coverage using extended X-ray adsorption fine structure spectroscopy (EXAFS). Cesium (Cs) possessed a variable coordination environment consisting of Cs-O distances between 3.2 and 4.3 A; however, disorder typical of the Cs coordination environments prevented the resolution of all oxygen...

Second harmonic generation (SHG) is applied for the first time to study the surfaces of clay particles. An SHG signal was detected from an aqueous suspension of disk-shaped montmorillonite clay particles of 0.5 μm diameter and 0.01 μm thickness. The origin of the SHG signal is the polarization of water molecules by surface charges located in the edge region of the clay particles. On addition of...