Poly (N-isopropylacrylamide)-co-acrylic acid (pNIPAm-co-AAc) microgel based assemblies (aggregates) were synthesized from microgels of various diameters via polymerization of the crosslinker N,N′-methylenebisacrylamide (BIS) in the presence of microgels in solution. We investigated the ability of the respective aggregates to remove the organic, azo dye molecule 4-(2-hydroxy-1-napthylazo) benzenesulfonic acid sodium salt (Orange II) from water at both room and elevated temperatures. The results from the microgel aggregates made from 1.1-μm-diameter [Parasuraman and Serpe. ACS Applied Materials & Interfaces, 2011] microgels were compared to aggregates synthesized from 321-nm and 1.43-μm-diameter microgels. Aggregates made from the same size microgels showed increased uptake efficiency as the concentration of BIS in the aggregates was increased, while for a given BIS concentration, the uptake efficiency increased with increasing microgel size in the aggregate. We attribute this to the "nature" of the aggregates; aggregates have void space between the microgels that can serve as reservoirs for Orange II uptake-the void spaces are hypothesized to increase with larger diameter microgels. By exploiting the thermoresponsive nature of the microgels, and microgel based aggregates, 85.3 % removal efficiencies can be achieved. Finally, all uptake trends for the aggregates, at room temperature, were fit with a Langmuir sorption isotherm model.

It is well known that, unlike the thermal efficiency of closed gas turbine cycles, the thermal efficiency of open gas turbine cycles varies with the fuel used in the combustion process. Presented in this paper is a thorough investigation of the effects of hydrocarbon fuels and alcohol fuels on the thermal efficiency of open gas turbine cycle. Among the open cycles with different fuels and otherwise identical specifications, the computed thermal efficiencies show a variation of about 2 percent between the extremes, which is appreciable. It was found that the thermal efficiency increases with a parameter of the fuel, c1 + c2, taken from the equation of reaction, c(Fuel)+O2→c1(CO2)+c2(H2O), and that the thermal efficiency of open gas turbine cycles is likely to be higher if the original fuel is replaced by a fuel which has a higher fuel parameter, c1 + c2. A universal correlation for both hydrocarbon fuels and alcohol fuels is presented in Fig. 1, plotting the thermal efficiency maximized from the pressure ratio variation, versus the parameter, c1 + c2. Alternatively, this correlation is also generalized by equation (2).

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