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Grain-oriented electrical steels (GOESs) are the main components of transformers, which should have low-energy losses and noise. Hence, GOESs should reduce iron loss and magnetostriction, which are determined by their magnetic domain structures. In particular, the angle and spacing of the 180° domain walls are the important characteristics of the GOES domain structures. In this study, we propose a method to rapidly quantify the spacing and angle of the walls of 180° magnetic domains in GOESs. The proposed method considers the magnetic domain structure as a 2-D dataset. The spacing and angle of the wall of the 180° magnetic domain of the polycrystal are obtained separately by transforming the dataset into a spatial frequency domain using 2-D Fourier transformation. The results obtained using the proposed method agree well with the experimental results, demonstrating the effectiveness of the proposed method.

Chiral phosphine-containing amino acids are useful motifs in pharmaceutical compounds. In this study, we developed the asymmetric conjugate addition of phosphine sulfides with α-substituted β-nitroacrylates to synthesize phosphine-containing amino acid precursors with chiral tetrasubstituted carbon centers. This method showed a wide substrate scope, and the obtained products were converted into various chiral compounds. The origin of the enantioselectivity was clarified by computational analysis.