Omar Langhoff (policepint3)
The first aim of this study was to synthesize and characterize reed-based-beads (BBR), an enhanced adsorbent from Tunisian reed. The second purpose was to evaluate and optimize the BBR efficiency for the simultaneous removal of oxytetracycline (OTC) and cadmium (Cd(II)), using central composite design under response surface methodology. The third goal was to elucidate the biosorption mechanisms taking place. It was shown that under optimum conditions (4.19 g L-1 of BBR, 165.54 μmol L-1 of OTC, 362.16 μmol L-1 of Cd(II), pH of 6, and 25.14-h contact time) the highest adsorption percentages (63.66% for OTC and 99.99% for Cd(II)) were obtained. It was revealed that OTC adsorption mechanism was better described by Brouers-Sotolongo fractal equation, with regression coefficient (R2) of 0.99876, and a Person's chi-square (χ2) of 0.01132. The Weibull kinetic equation better explained Cd(II) biosorption (R2 = 0.99959 and χ2 = 0.00194). FTIR and isotherm studies confirmed that the BBR surface was heterogeneous, and that adsorption mechanisms were better described by the Freundlich/Jovanovich equation (R2 = 0.99276 and χ2 = 0.04864) for OTC adsorption, and by the Brouers-Sotolongo model (R2 = 0.9851 and χ2 = 0.77547) for Cd(II) biosorption. Overall results indicate that, at last, the BBR lignocellulosic biocomposite beads could be considered as cost-effective and efficient adsorbent, which could be of socioeconomic and environmental relevance. Graphical abstract.Sheep are important livestock and a source of milk, meat, and wool globally. The increasing demand for animal protein requires increased productivity in sheep. In vitro fertilization and maturation can improve sheep productivity. The aims of this study were to evaluate the effects of honey bee addition as a supplementation medium on in vitro maturation improvement, gene expression of matured sheep oocytes, and determine the optimum concentration from honey bee for in vitro maturation of sheep oocytes. Cumulus oocyte complexes were obtained from the ovaries of slaughtered female sheep. Grade A and B oocytes were cultured for 24 h in medium without honey bee (control, G1) or medium supplemented with 5% (G2), 10% (G3), or 20% (G4) honey bee. ABT-199 ic50 Oocyte maturation rate, glutathione concentration, and the expression of candidate genes (GDF-9, BAX, Cyclin B, C-MOS, IGF1) were determined in the matured oocytes. The maturation rate of sheep oocyte was better in the presence of 5% and 10% honey bee; the mean number of oocytes in metaphase II stage was higher than that in G1 and G4 groups. Glutathione concentration was highest in G2 (10.93 ± 0.57). In general, gene expression levels were similar in G2 and G3, which were greater that in G1 and G4. In conclusion, the optimal concentration of black seeds honey bee that can be added to the maturation medium is 5% to obtain the highest mean MII and glutathione concentration values, and to improve gene expression in in vitro matured sheep oocytes.Thermal barrier coating (TBC) implementations and oxygenated additives are remarkable issues that may decrease the exhaust emissions of engines. This study examines the effect of chromium oxide (Cr2O3) coating and the addition of ethylhexyl nitrate (EHN) on exhaust emissions of a diesel engine. In addition, an artificial neural network (ANN) model was designed which estimates exhaust emissions based on engine speed in order to reduce time, labor, and costs lost in experimental studies, and the performance of the ANN was evaluated. Piston crown and valves of engine were processed with Cr2O3. The E3, E6, and E9 blends were produced by blending 3%, 6%, and 9% (vol.) ratios of 2-ethylhexyl nitrate with diesel fuel. Engine speed was used as input parameter and carbon monoxide (CO), nitrogen oxide (NOX), hydrocarbon (HC), and smoke density were used as output parameters. To evaluate the performance of ANN, error rates, and regression (R) values were considered. Experimental results revealed that