it seems that the presence of soil organic matter (som) increases p availability to plants. this effect has commonly been ascribed as competition between the decomposition products of som and p for soil sorption sites resulting in p concentrations increase of soil solution. this study was carried out to obtain information about soil organic matter (som) influence on kinetics and thermodynamics ...

An attempt has been made in this paper to investigate the effect of particle size distribution on coal flotation kinetics. The effect of particle size (Ps) on kinetics constant (k) and maximum theoretical flotation recovery (RI) was investigated while other operational parameters were kept constant. The relationship between flotation kinetics constant and theoretical flotation recovery with par...

risk-based assessment methods are commonly used at the contaminated sites by hydrocarbon pollutants. this paper presents the results of a two-dimensional finite volume model of reactive transport of biodegradable btex which have been developed for the saturated zone of an unconfined aquifer in the pump station area of tehran oil refinery, iran. the model governing equations were numerically sol...

the removal of cd2+ and pb2+ ions from wastewater using p-tert-butyl-calix[4] arene was investigated in terms of initial ph, initial concentration, adsorbent dosage, contact time and temperature. the maximum adsorption occurred at the ph value of 6. the adsorbent studied exhibits high efficiency for cd (ii)and pb (ii) adsorption and the equilibrium states could be achieved in 10 min. adsorption...

today hydrogels are considered as the materials that are able to play important role in drug delivery systems. to design an effective hydrogel applicable network, mathematical modeling has a critical role. a successful drug delivery device relies not only on intelligent network design but also on accurate prior mathematical modeling of drug release profiles. in this study, the modeling of the i...

Mathematical form for two energy groups of three-dimensional homogeneous reactor kinetics equations and average one group of the precursor concentration of delayed neutrons is presented. This mathematical form is called “two energy groups of the point kinetics equations.” We rewrite two energy groups of the point kinetics equations in the matrix form. Generalization of the analytical exponentia...