Propionic acid modified bagasse was used for the removal of reactive yellow 2 and reactive blue 4. The effects of pH, contact time, initial dye concentrations, adsorbent particle size and adsorbent dose on the adsorption of the two dyes were investigated. Additionally, the desorption process and intra-particle diffusion were studied. Acidic pH values were favorable for adsorption of both dyes. The equilibrium adsorption data were best fitted with the Freundlich isotherm for reactive yellow 2 and the Langmiur isotherm for reactive blue 4. The values of their corresponding constants were de-termined. The kinetic for dye adsorption is well described by a pseudo-first order kinetic model for the reactive yellow 2 and by pseudo-second order for the reactive blue 4. The investigation revealed that the hydroxyl groups of bagasse and the carboxylic group of propionic acid play a great role in the removal of both reactive dyes.

This research work involved the use of the low cost, available and renewable biosorbent propionic acid pretreated bagasse for the removal of the textile direct yellow 12 and direct red 81 dyes from aqueous solutions. Batch experiments were carried out for sorption kinetics and isotherms of the two dyes. The studied operating variables include initial pH, contact time, initial dye concentration, adsorbent dose and particle size. Maximum color removal was in acidic medium (pH 2.5-3.5) where a greater percentage removal was observed in this pH range. Equilibrium isotherms were applied using Langmuir and Freundlich models of adsorption and it was found that the Langmuir isotherm was the best model for adsorption of direct yellow 12 whereas the Freundlich model was suitable for adsorption of the direct red 81. The kinetics of adsorption of both dyes was consistent with a pseudo-first order kinetic for the direct yellow 12 and a pseudo-second order for the direct red 81. Desorption of both dyes is greatly dependent on the pH value of the solution with which the bagasse loaded dye in contact. The percent dye removal increases with the pH increase.

Raw sugarcane bagasse modified with propionic acid (RBMPA) was used as an efficient, low cost and eco-friendly adsorbent for the removal of methylene blue (basic) and orange II (acid) dyes from aqueous solutions. The effect of different system variables, namely contact time, dye concentration, adsorption dose, pH and particle size were investigated and optimal experimental conditions were ascertained. A greater percentage of dye removal was observed in acidic medium (pH=2) in case of orange II whereas in (pH=7) in case of methylene blue dyes and increases with the in-crease of the dosage of adsorbent. Maximum dye removal was attained after 60 min. Equilibrium isotherms were analysed by the Langmuir and Freundlich models of adsorption and it was found that the Langmuir isotherm provides a good model for the adsorption of methylene blue whereas the Freundlich isotherm is fit for the adsorption of orange II. The kinetics of the adsorption of both dyes was consistent with pseudo second-order kinetics with a good correlation (R2 > 0.99). Further-more, the amounts of dye adsorbed at equilibrium, qe (mg g-1) for methylene blue and orange II were 59.5 and 25.5, respec-tively.

Aregular two- parameter perturbation analysis based upon the boundary layer approximation is presented here to study the radiative effects of both firs- and second- order resistances due to a solid matrix on the natural convection flows in porous media

A regular perturbation analysis is presented for the following laminar natural convection flow of Newtonian fluids with temperature -dependent effective viscosity: a freely -rising plane plume, the flow above a horizontalline source on an adiabatic surface and the flow adjacent to a vertical uniform flux surface for porous medium

The use of steroid-treated feeds as 17 a-methyltestosterone for the production of all-male populations is widespread in tilapia aquaculture. The aim of the present study was to investigate the misuse effects of methyltestosterone on monosex farmed Nile tilapia, Oreochromis niloticus by evaluation of hematological and biochemical values. The fishes were obtained from four localities (Assiut as a control, Beheira, Alexandria and Kafr el-Sheikh: three farms from each governorate as farmed monosex produced using methyltestosterone). The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), white blood cell count, blood platelets, lymphocyte, monocyte, neutrophils and basophils were determined. The results showed that there were changes in the erythrocytic series and in the defense white blood cells. Activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP), glucose, cholesterol, total protein, uric acid and creatinine were determined for biochemical study. These alterations are considered an indication for performance and health of fish in the monosex culture medium indicating the side effects of overdose induction of MT.

From a previous study we have determined that commercial security products can suffer from a usability perspective, lacking the necessary attention to design in relation to their alert interfaces. The aim of the paper is to assess the usability of alerts in some of the leading Internet security packages, based upon a related set of usability criteria. The findings reveal that the interface design combined with the user’s relative lack of security knowledge are two major challenges that influence their decision making process. The analysis of the alert designs showed that four of the criteria are not addressed in any of the selected security measures and it would be desirable to consider the user’s previous decisions on similar alerts, and modify alerts according to the user’s previous behaviour.