Polymer concretes (PCs) were created by using varying concentrations of silica sand as aggregate and also hematite, colemanite and a commercial epoxy resin. Hematite is known to exhibit radiation shielding properties. Mechanical performance was evaluated including unit weight, pulse velocity, compressive strength, flexural strength, splitting tensile strength, modulus of elasticity and dynamic ...

Complex life cycles have evolved independently numerous times in marine animals as well as in disparate algae. Such life histories typically involve a dispersive immature stage followed by settlement and metamorphosis to an adult stage on the sea floor. One commonality among animals exhibiting transitions of this type is that their larvae pass through a 'precompetent' period in which they do no...

The toxicity and horizontal transmission of thiamethoxam was evaluated in the workers of the Asian subterranean termite Coptotermes gestroi Wasmann (Isoptera: Rhinotermitidae). Brief exposure to sand treated with thiamethoxam at concentration ranging from 0.25 to 50 µg/ml resulted in a dose-dependent mortality in C. gestroi. Sand treated with 50 µg/ml thiamethoxam resulted in very high mortalit...

Aggregations of Oreaster reticulatus (L.) in a large sand patch amid an offshore seagrass bed (Syringodium filiforme) off St. Croix (US Virgin Islands) were characterized by protracted fronts of high density (2-7 individuals m-2). Fronts mlgrated across the sand patch at approximately 7 m d-l and were refracted and deflected at the grassbed border. Intensive microphagous feeding effected a 2-fo...

The secondary treated effluents of pulp and paper mills contain high chemical oxygen demand (COD) that is associated with organic matter. Therefore, this study explores the adsorption substances contributing to COD using CoFe2O4 quartz sand-coated in batch fixed-bed column experiments. X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller analysis, photoelectron spectroscopy w...

The adsorption of [3H]thymidine-labeled plasmid DNA (pHC314; 2.4 kb) of different conformations to chemically pure sand was studied in a flowthrough microenvironment. The extent of adsorption was affected by the concentration and valency of cations, indicating a charge-dependent process. Bivalent cations (Mg2+, Ca2+) were 100-fold more effective than monovalent cations (Na+, K+, NH4+). Quantita...

this experiment was carried out to investigate the effect of different substrate on growth and yield of gerbera flower. the experiment was performed using 10 treatments as fallow: fine sand, peat +fine sand (%25+%75), peat + fine sand ( %50 +%50), perlite + peat (%75 + %25), perlite + peat (%50 + %50), perlite + peat (%25 + %75), perlite + peat + expanded clay (%25 + %70 + %5), perlite + peat +...

In this study the concept of biofilm accumulation in the sand column was promoted to assess the changes in hydraulic conductivity and concentration of organic contaminants of the synthetic leachate. Four different combinations of column study were carried out using synthetic leachate as a substrate solution. Mixed and stratified mode of experiments with two different sizes (0.3 mm and 0.6 mm) o...

Atrazine is a widely used herbicide in agriculture. Non-point source contamination of groundwater and drinking water may pose a significant threat to humans, wildlife, and the environment. Phytoremediation may provide a cost-effective strategy for reducing non-point source contamination of atrazine from agricultural runoff. Previous studies have shown that the rhizosphere of the native prairie ...