abstract siderophores are of important factors influencing bioavailability and fate of heavy metals in the arid and semi-arid soils. they are low molecular weight organic ligands excreted by aerobic soil microorganisms and some plants roots to acquire fe. siderophores may also complex other metals such as pb .the main objective of this study was to investigate the effects of dfob-siderophore on...

Several factors effect on sorption of polycyclic aromatic hydrocarbons (PAHs) in soil. Coexistence of metals and organic matter of soil are among important affecting factors on sorptive behavior of PAHs. This research investigated the effect of organic matter content and heavy metals (lead, nickel and zinc), on sorption of phenanthrene onto kaolinite. For this purpose, sorption of the organic m...

The present study deals with the utilization of a cellulosic material, i.e. fungal biomass of Mucor heimalis, for the removal of cadmium from aqueous solution in a batch system. Effects of various parameters such as pH, biomass dosage, contact time, and initial metal concentrations were investigated. The sorption of cadmium followed pseudo-secondorder rate kinetics (R=0.998). Intraparticle diff...

Surface coal mine spoil was studied to evaluate selenium (Se) mobility and solubility using batch experiments, column-Ieachmg techniques, and sequential and individual extraction processes. Both selenite and selenate followed linear isotherm patterns at relatively lower Se treatments, whereas over a broader solution Se concentraton range the sorption mechanism followed the Lanpuir model. The va...

Phosphorus sorption characteristics of some Indian representative agricultural soils belonging to four soil orders namely Vertisol, Inceptisol, Alfisol and Ultisol were investigated for adsorption behaviour of P and sorption data were fitted to Langmuir and Freundlich equations. The Langmuir constant i.e. adsorption maxima was highest for Vertisol (716.85 μg g -1 ), followed by Ultisol (633.3 μ...

we utilize isotherm models in contributing to scholarly knowledge in simple terms, to measure the forces or energy defining certain adsorption phenomenon. gas chromatography coupled with mass spectrophotometer detector (gcms) was utilized to measure equilibrium phase atrazine after adsorption onto shea nut shells (ss) acid derived activated carbon. data were fitted into the d-r and temkin isoth...

Water sorption by plant cuticular membrane isolates, mainly identified as polysaccharides, after selective extraction of the lipid components waxes and cutin was measured over the whole range of water activity. From water sorption isotherm, the strengths of water binding and water clustering were estimated. Data obtained by differential scanning calorimetry and Fourier-transform and near infrar...

-Sorption isotherms for four gases (N2, A, Kr and C O 2 ) , commonly used in specific surface area and pore structure measurements, have been accurately determined on a number of clay mineral and oxide systems. Specific surface areas obtained by application of the BET theory to these isotherms illustrate the extent to which the apparent cross-sectional areas for these sorbed gases vary with sur...

14 The mechanisms of sorption of four steroidal hormones – estradiol, estrone, progesterone and 15 testosterone – to electrodialysis (ED) membranes were investigated as a function of solution pH 16 and presence of humic acid (HA). Hormone-membrane partition coefficients (log KAEM/CEM) 17 determined through sorption isotherm experiments suggested that hormone sorption was due to 18 hydrogen bond...

We present a numerical scheme for reactive contaminant transport with nonequilibrium sorption in porous media. The mass conservative scheme is based on Euler implicit, mixed finite elements, and Newton method. We consider the case of a Freundlich-type sorption. In this case, the sorption isotherm is not Lipschitz but just Hölder continuous. To deal with this, we perform a regularization step. T...