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Oxygen sorption/desorption properties of SrCo x Fe1-x O3−δ were examined as an oxygen sorbent for a high-temperature pressure-swing adsorption (HT-PSA) process. Perovskite-type structure of the SrCo x Fe1-x O3−δ powder samples was observed in the composition range of 0 ≤ x ≤ 0.85, by using XRD measurements. A temperature-programmed-desorption (TPD) measurement revealed that the oxygen desorption temperature in N2 for the perovskite-type SrCo x Fe1-x O3−δ samples was lowered with increasing x. Consequently, the oxygen desorption temperature of the SrCo0.85Fe0.15O3−δ sample exhibited around 300 °C, which was the lowest of those of the examined samples. A high-temperature X-ray diffraction (HT-XRD) measurement suggested that the oxygen desorption of SrCo0.85Fe0.15O3−δ in N2 occurred, accompanying the phase transition from perovskite-type structure to brownmillerite structure. Isothermal oxygen sorption/desorption behavior of the SrCo x Fe1-x O3−δ samples was examined by means of thermogravimetric analysis (TGA). As a result, it was confirmed that the amount of sorbed oxygen for the SrCo0.85Fe0.15O3−δ sample gave 11.7 cm³ g-1 at 300 °C, which was larger than that (8.6 cm³ g-1) for a benchmark oxygen sorbent (La0.1Sr0.9Co0.9Fe0.1O3−δ). In order to obtain oxygen-enriched air by using the SrCo0.85Fe0.15O3−δ pellet sample as the oxygen sorbent, the oxygen separation from synthetic air was carried out by using a small-scale PSA apparatus equipped with a vacuum pump. It was confirmed that the 45 vol % oxygen-enriched air was obtained even at 300 °C, by using this apparatus. [ABSTRACT FROM AUTHOR]

Solvent, temperature, and excitationwavelength significantly affectedthe photochemical outcomes of a naphthalene–dicyanoethene systemtethered by different number (n) of methylene groups(1–3). The effect of irradiationwavelength was almost negligible for 2abut pronouncedfor 3a. The temperature dependence and theoretical calculationsindicated the diversity of exciplex conformations, an ensemble ofwhich can be effectively altered by changing excitation wavelengthto eventually switch the regioselectivity of photoreactions. [ABSTRACT FROM AUTHOR]