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Fe-Mn-Si-Cr-based shape-memory alloys have excellent properties of formability, shape-memory effect, and low cost. These properties make Fe-Mn-Si-Cr SMAs ideal candidates for the application of pipe coupling and fish plates. In this study, we add slight Rhenium (Re, 0.05-0.3 wt.%) to Fe-30Mn-6Si-5Cr alloys to improve their shape-memory effect. The martensitic transformation, crystal structure, and aging precipitate of the Fe-30Mn-6Si-5Cr-Re alloys are analyzed. The optimization of shape-memory performance of Fe-30Mn-6Si-5Cr-Re alloys can be achieved efficiently by the proper combined treatments of pre-strain, aging, and shape-memory training.

Cyanine dye J-aggregate films are a class of absorbing and luminescent materials which have been extensively applied in the polariton-based research. Here we systematically study the DEDOC cyanine dyes J-aggregate films made by layer-by-layer assembly and spin-coating processes to establish a clear correlation between the film structure and the absorption and luminescence properties. From detailed analyses of morphology, optical spectra, and light-emitting diode characteristics, we demonstrate that layer-by-layer assembled film has higher degrees of homogeneity and molecular packing quality than spin-coated film, leading to a higher absorption coefficient, more uniform luminescence, and a greater electroluminescence quantum efficiency with maximized thickness.

Deactivation of a lanthanum exchanged zeolite Y catalyst for isopropylbenzene (cumene) cracking was studied with a thermobalance. The kinetics of coke formation and the main reaction were determined. The Froment Bischoff approach to modeling catalyst deactivation was used. The deactivation function giving the best fit to both the cracking and coking reaction data was an exponential one related to the coke content of the catalyst. The kinetic mechanism for coking that gave the best fit was one in which parallel and consecutive coking reactions occurred simultaneously. Apparently, more coke forms from products than reactants, especially at higher temperature.