This reaserch aims at functionalizing magnetic mesoporous silica with methacrylic acid-3-aminopropyltriethoxysilane (Fe3O4@MCM-41@MAA-APTES) applied for removal of methylene blue from aqueous solution. Several variables (such as pH, dye concentration, adsorbent amount and contact time) have been investigated. Under optimum conditions, maximum capacity of 87.71 mg g-1 of MB was obtained for the ...

an improved mixed order model is presented to describe the thermolumunescence (tl) glow peaks. in this model a fraction of charge carriers, which undergo nonradiative recombination following thermal excitation is taken into account. therefore, it is expected that the proposed model will produce more realistic kinetic parameters than that of mixed order model. the tl glow curves generated by the...

batch experiments were conducted to study the adsorption behaviors of lead ion (pb2+) onto ferrihydrites prepared using three different procedures which were characterized  by textural analysis (bet). the adsorption removal of pb2+ by the three ferrihydrites (called fh-1, fh-2 and fh-3, respectively) were compared, and fh-3 shows fast adsorption kinetics as well as high adsorption capacities, t...

Methods to derive macroscopic transport equations for rarefied gases from the Boltzmann equations are presented. Featured methods include the Chapman-Enskog expansion, Grad’s moment method, and the author’s order of magnitude method. The resulting macroscopic equations are compared and discussed by means of simple problems, including linear stability, shock wave structures, and Couette flow.

To elucidate slow dynamics in glassy materials, we introduce the figure-8 model in which N hard blocks undergo Brownian motion around a circuit in the shape of a figure 8. This system undergoes kinetic arrest at a critical packing fraction phi=phi g<1 , and for phi approximately phi g long-time diffusion is controlled by rare, cooperative, "junction-crossing" particle rearrangements. We find th...

We present an algorithm specifically tailored for solving kinetic equations onto GPUs. The efficiency of the algorithm is demonstrated by solving the one-dimensional shock wave structure problem and a two-dimensional low Mach number driven cavity flow. Computational results show that it is possible to cut down the computing time of the sequential codes of two order of magnitudes. The algorithm ...