Phase-shift-difference (PSD) spectra upon reflection are measured at 110 K and 20 K on CuGaS2xSe2(1-x) and CuAlS2xSe2(1-x) alloy systems. The spectra reveal so-called A, B and C excitonic structures which are associated with the splitting of the uppermost valence band. In addition, the first excited state of the A-exciton is observed at 20 K in CuGaS2xSe2(1-x) system, and the binding energy of the exciton is estimated by using the hydrogen model. Analysis by Hopfield's quasi-cubic model for the spin-orbit and crystal field splittings is found to be inapplicable to these compounds. The crystal field splitting is always larger than expected in these compounds. This effect as well as anomalously small spin-orbit splitting are explained by p-d hybridization of the valence band.

N,N-Dimethylformamide-stabilized Ru nanoparticles (NPs) provide a highly efficient catalyst for the Guerbet reaction of primary alcohols under solvent-free conditions and without the use of external ligands.

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