Critical behavior and magnetic-entropy change of orthorhombic La0.7Ca0.2Sr0.1MnO3 J. Appl. Phys. 112, 093906 (2012) Reversible solid-state hydrogen-pump driven by magnetostructural transformation in the prototype system La(Fe,Si)13Hy J. Appl. Phys. 112, 083918 (2012) Magnetocaloric effect and nature of magnetic transition in nanoscale Pr0.5Ca0.5MnO3 J. Appl. Phys. 112, 083917 (2012) On the estimation of the magnetocaloric effect by means of microwave technique AIP Advances 2, 042120 (2012) Magnetocaloric properties of La0.7Ca0.3Mn16O3 and La0.7Ca0.3Mn18O3 manganites and their "sandwich"A systematic study of the conventional and inverse magnetocaloric effects and critical behaviors in Ni 50 Mn 50Àx Sn x (x ¼ 13 and 14) alloy ribbons has been performed. We show that although the magnetic entropy change around the second-order ferromagnetic-paramagnetic (FM-PM) transition (DS m % À4 J/kg K) in the austenitic phase is about five times smaller than that around the first-order martensitic-austenitic (M-A) transformation (DS m % 22 J/kg K), the refrigerant capacity (RC) -an important figure of merit -is about two times larger for the former case (RC % 160 J/kg) than for the latter case (RC % 75 J/kg). This finding points to an important fact that to assess the usefulness of a magnetocaloric material, one should not only consider DS m but also must evaluate both DS m and RC. Our critical analysis near the second-order FM-PM transition reveals that Sn addition tends to drive the system, in the austenitic FM phase, from the short-range (x ¼ 13) to long-range (x ¼ 14) FM order.
The ballistic transport properties of Cu nanowires (NWs) under electric fields are investigated using firstprinciples density function theory for future application as interconnects in microelectronics. It is found that as electric field strength increases, the amount of quantum conduction of a nonhelical atomic strand decreases, while that of a helical atomic strand is in an opposite tendency. The changes are decided by the changes of atomic layer distance of the NWs and the related electronic distribution along the axis of the NWs.
Polycrystalline samples of BaTiO3 doped with 2.0 at. % Mn were prepared by solid-state reaction at various temperatures (Tan) ranging from 500 to 1350 °C, used high-pure powders of BaCO3, TiO2, and MnCO3 as precursors. Experimental results obtained from x-ray diffraction patterns and Raman scattering spectra reveal that tetragonal Mn-doped BaTiO3 starts constituting as Tan ≈ 500 °C. The Tan increase leads to the development of this phase. Interestingly, there is the tetragonal-hexagonal transformation in the crystal structure of BaTiO3 as Tan ≈ 1100 °C. Such the variations influence directly magnetic properties of the samples. Besides paramagnetic contributions of Mn2+ centers traced to electron spin resonance, the room-temperature ferromagnetism found in the samples is assigned to exchange interactions taking place between Mn3+ and Mn4+ ions located in tetragonal BaTiO3 crystals.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.