Fluidized-bed bioreactors (FBBR’s) offer a promising alternative to existing treatment technologies for the treatment of water contaminated with chlorinated solvents. The objective of this research was to test a laboratory-scale FBBR for removal of trichloroethene (TCE) from groundwater and to study the FBBR kinetic behavior so that field-scale treatment systems could be designed. Phenol was se...

A study was performed to investigate the efficiency of rhizobacteria on solubilization of rock phosphate and their assimilation by wheat plants in quartz sand potted experiments. Two phosphate solubilizing bacteria, P. fluorescens and Serratia sp. were encapsulated in sodium alginate and potato starch beads and selected to investigate the variation on pH values, the enzymatic activity of alkali...

In this paper, we characterize the filtration and deposition profiles of a recombinant analog of Norwalk virus, an important waterborne pathogen, in packed beds of saturated quartz sand under both ‘clean-bed’ and ‘dirty-bed’ conditions. Under clean-bed conditions with NaCl as the electrolyte, the retained Norwalk virus particles decline like a power-law with depth. The power-law decay in retain...

The behaviour of a granular material is mainly dependent on its frictional properties, angle of internal friction, and cohesion, which, together with material density, are the key factors to be considered during the scaling procedure of analogue models. The frictional properties of a granular material are usually investigated by means of technical instruments such as a Hubbert-type apparatus an...

This study aims to determine the reasons for increase in frequency of sand and dust storms Middle East identify their sources mitigate them. A set climatic data from 60 years (1960–2022) was analyzed. Sand Iraq are a silty mature arkose composed 72.7% sand, 25.1% silt, 2.19% clay; clay fraction constitutes 70%, with small amount silt (20.6%) (9.4%). Dust (%) quartz (49.2, 67.1), feldspar (4.9, ...

The objectives of this work were (i) to use transposon mutagenesis to produce mutants of Pseudomonas fluorescens that were altered in adhesion ability and transport through porous media and (ii) to identify the alterations in surface characteristics that were responsible for the changes in attachment. Mutants of P. fluorescens were generated with TnphoA, which enabled identification of mutants ...

On-off cycles of production wells, especially in bank filtration settings, cause oscillations in the local water table, which can deliver significant amounts of dissolved oxygen (DO) to the shallow groundwater. The potential for DO introduced in this manner to oxidize manganese (Mn), mediated by the obligate aerobe Pseudomonas putida GB-1, was tested in a column of quartz sand fed with anoxic i...