RESUMEN
The nucleation mechanism involving rapid solidification of undercooled La-Fe-Si melts has been studied experimentally and theoretically. The classical nucleation theory-based simulations show a competitive nucleation process between the α-(Fe,Si) phase (size approximately 10 to 30 nm) and the cubic NaZn13-type phase (hereinafter 1:13 phase, size approximately 200 to 400 nm) during rapid solidification, and that the undercooled temperature change ∆T plays an important factor in this process. The simulated results about the nucleation rates of the α-(Fe,Si) and 1:13 phases in La-Fe-Si ribbons fabricated by a melt-spinner using a copper wheel with a surface speed of 35 m/s agree well with the XRD, SEM, and TEM studies of the phase structure and microstructure of the ribbons. Our study paves the way for designing novel La-Fe-Si materials for a wide range of technological applications.
RESUMEN
In the crystal structure of the title compound, C(8)H(5)N(3)O(3), inter-molecular N-Hâ¯O hydrogen bonds link mol-ecules into centrosymmetric dimers. These dimers are, in turn, linked though weak inter-molecular C-Hâ¯O and C-Hâ¯N hydrogen bonds and π-π stacking inter-actions, with centroid-centroid distances of 3.678â (3)â Å, into a three-dimensional network.
