As reported on the literature for different kinds of NPs, the amount of retained NPs decreased Erastin supplier when the water velocity increased. Moreover,
no retention was observed for ionic strength values smaller than 5 mM. A transport model coupling convective-dispersive transport with a Langmuirian kinetic deposition was used to fit the BTCs. Empirical linear equations were developed to estimate the attachment rate k(a) and the maximal solid phase concentration s(max). Both parameters were found to be linearly depending on the collector efficiency (eta(0)). It was also observed that attachment efficiency (alpha) did not change with increase of water velocity under the given experimental conditions and that the model had a low sensitivity to alpha. Based on these estimates of the retention parameters, the classical dispersion-convection model coupled with a Langmuir type adsorption model was able to reproduce quite well the observed TiO2 breakthrough curves for every fluid velocity used in the experiments. (C) 2014 Elsevier B.V.
All rights reserved.”
“Cellulose was isolated from corn stalk and modified by graft copolymerization to produce an absorbent material (AGCS-cell), which was characterized by scanning electron microscope and energy disperse spectroscopy (SEM-EDS), X-ray diffraction (XRD) and solid-state CP/MAS C-13 NMR. The results showed that AGCS-cell had better adsorption potential for cadmium ion than unmodified cellulose because of the addition of functional ALK inhibitor groups (-CN and -OH selleckchem groups) and the lower crystallinity.
The Langmuir isotherms gave the best fit to the data and gave an adsorption capacity was 21.37 mg g(-1), which was close to unpurified cellulose (AGCS) and reflected the feasibility of using AGCS-cell as an adsorbent to remove cadmium ions. (C) 2012 Elsevier Ltd. All rights reserved.”
“A systematic investigation on the effects of auxotrophies on the performance of yeast in aerated fed-batch reactor was carried out. Six isogenic strains from the CEN.PK family of Saccharomyces cerevisiae, one prototroph and five auxotrophs, were grown in aerated fed-batch reactor using the same operative conditions and a proper nutritional supplementation. The performance of the strains, in terms of final biomass decreased with increasing the number of auxotrophies. Auxotrophy for leucine exerted a profound negative effect on the performance of the strains. Accumulation of reactive oxygen species (ROS) in the cells of the strain carrying four auxotrophies and its significant viability loss, were indicative of an oxidative stress response induced by exposure of cells to the environmental conditions. The mathematical model was fundamental to highlight how the carbon flux, depending on the number and type of auxotrophies, was diverted towards the production of increasingly large quantities of energy for maintenance. (C) 2011 Elsevier Inc. All rights reserved.