[PDF] Top 20 Braz. J. Chem. Eng. vol.28 número3

... Schiffman and Schauer (2007) reported that chitosans with a low (70 kDa), medium (190–310 kDa), and high (500 kDa) molecular weight, as well as a commercial chitosan (190–375 kDa) sample, were dispersed in 2.7% TFA. With ... See full document

... The addition of 0.001 and 0.008 g.L -1 of nickel to the zinc sulfate electrolyte with 5 g.L -1 of magnesium increased the mass of electrodeposited zinc and the current efficiency...[r] ... See full document

... The results for the Gibbs free energy ( ΔG; kJ/mol) indicate that, at the temperatures of the first phase (47-51°C), the immobilized enzyme has (Figure 3) a more stable intrinsic conformational form, since the values are ... See full document

... It was demonstrated that zeolite 13X adsorbed carbon dioxide and nitrogen to its total capacity and, thus, the equilibrium of CO2 and N2 adsorption for CO2/N2 mixtures can be very we[r] ... See full document

... 4) There is no definite trend for total unburned hydrocarbon emissions (HC) with increasing engine power and water content. 5) NOx emissions increased with increasing engine power a[r] ... See full document

... It has been shown by Tian et al. (2009) that the (RNG) k– model provides a more satisfactory description of the flow pattern and the turbulence properties than standard k- in the wavy fin-and-tube heat exchangers. ... See full document

... The addition of K promoter decreases the BET surface area and pore volume of Fe/Cu/K catalysts compared to Fe or Fe/Cu catalysts; thus, the effect reported in Table 2 is due to the a[r] ... See full document

... However, in the case of xanthan and guar dispersions, higher values for the complex viscosity were observed as compared to the apparent viscosity within the frequency and shear rate [r] ... See full document

... To study the flocculation process at high effective shear rate G eff approaching that in some papermaking mills, the flocculation experiment was performed in a flow loop (Fig. Fines[r] ... See full document

... ƒ For our experimental conditions and a long contact time (60 min), the costs related to ozone application to sediments for purposes of both disinfection and settleable solids reducti[r] ... See full document

... In the present study, we prepare thin film composite membranes by preparing asymmetric polyether sulfone membranes in a water gelation bath, mixed with 1,3-phenylene diamine with int[r] ... See full document

... The results in Table 3 show that Ca 2+ ion is significantly activating for both free and immobilized tannase (residual activity is 118% and.. 112.4% for immobilized and free tannase, [r] ... See full document

... For CeO2, CeO2-TiO2-Al2O3 and Ag/CeO2-TiO2- Al2O3, the specific surface area and specific external area decreased, and an increase in the micropore surface area occurred due to the cr[r] ... See full document

... Activities on different substrates were tested, showing that enzyme A could be efficiently used for leather unhairing due to its good activity on keratin azure and azocoll, with enzym[r] ... See full document

... ƒ Test 3 (preoxidation with chlorine dioxide and adsorption on GAC): chlorine dioxide solution flow: 0.3 L.h -1 ; water flow: 2.0 L.h -1 ; duration of the test: 14 h; control paramete[r] ... See full document

... Because the model reproduced the experimental behaviour satisfactorily for the column operation, it was then used to analyse the influence of parameters such as oxygen diffusion coeff[r] ... See full document

... The Stokes number (St =0.15) is less than unity, so that the particle follows the fluid motion well. Direct numerical simulations were performed for the fully developed single–liquid[r] ... See full document

... At low and medium values of the pulsation intensity, the effect of the interfacial area is larger than that of the overall mass transfer coefficient and, consequently, the overall col[r] ... See full document

... Desalination is a novel application of zeolitic membranes for the treatment of hazardous wastes (Duke et al., 2007), although other inorganic membranes have been used to concentrate [r] ... See full document

... The results obtained for this test piece show that the final mechanical properties of the bone cement become much better after some time, probably due to the reduction of the amount o[r] ... See full document