Expansive soils owe their characteristics to the presence of swelling clay minerals. As they get wet, the clay minerals absorb water molecules and expand; conversely, as they dry they shrink, leaving large voids in the soil. Swelling clays can control the behavior of virtually any type of soil if the percentage of clay is more than about 5 percent by weight. Soils with smectite clay minerals, s...

abstract a study was conducted to evaluate the effect of incubation time, sewage sludge and clay content on the distribution of nickel and cadmium in different fractions of selected calcareous soils. to meet this purpose, an experiment with two different soils (4 and 30 percent caco3), two different textures (8 and 40 percent clay), two levels of nickel (0 and 100 mg.kg-1), two levels of cadmiu...

Seeds from Pachira brevipes from white-sand forest and Pachira insignis from clay forest were placed in a reciprocal transplant experiment that manipulated herbivore presence. Pachira insignis experienced 80 percent leaf loss in both habitats from herbivores, causing 79 percent mortality in white-sand compared with 47 percent in clay in just 3 mo. Pachira brevipes suffered pathogen attack in bo...

A large quantity of sludge is generated each year from water treatment plants in Egypt. Disposing the sludge to the nearest water stream is the common practice in Egypt, which accumulatively rise the aluminum concentrations in water and consequently in human bodies. This practice has been linked to occurrence of Alzheimer’s disease. Landfill disposal of the sludge is impractical because of the ...

using of different systems of soil plough after changing unconsciously and non-scientific of land use, other soil physical and chemical characteristics affected. this fact, especially in marginal lands and mountainous regions is more visible. this research compared with the purpose of studying land use changing on some soil physical and chemical characters like very tiny sand percent, ph, ec, c...

Bacteria were released and separated from soil by a simple blending-centrifugation procedure. The percent yield of bacterial cells (microscopic counts) in the supernatants varied over a wide range depending on the soil type. The superantants contained large amounts of noncellular organic material and clay particles. Further purification of the bacterial cells was obtained by centrifugation in d...

Preparation of a novel organically modified clay from spent oil base drilling mud (SOBM) that could serve as core-shell clay filler for polymers is herein reported. Due to the hydrophilic nature of clay, its compatibility with polymer matrix was made possible through modification of the surface of the core clay sample with 3-aminopropyltriethoxysilane (3-APTES) compound prior to its use. Fourie...