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The structural stability and physical properties of CaCu3Fe4O12 were studied by the use of the full-potential linearized augmented plane wave method. The authors’ calculated result indicates that the title compound is stable both thermodynamically and mechanically. It is ferrimagnetic and half-metallic. The calculated magnetic structure reveals that the coupling of Cu–Fe is antiferromagnetic, while those of Cu–Cu and Fe–Fe are ferromagnetic.

The electronic and magnetic properties of tetragonal double perovskite Sr(2)NiOsO(6) were studied by use of the density functional theory and including the spin-orbit coupling. Compensated half-metal is found if the spin-orbit coupling is not considered. Spin-orbit coupling induces orbital moments on both Ni and Os, making Sr(2)NiOsO(6) a near compensated half-metal. Ferromagnetic phase is slightly favored over antiferromagnetic phase (by 4 meV). The small energy difference also suggests that both phases are competitive for the ground state. At ferromagnetic phase, the calculated net magnetic moment is 3.53 micro(B), in good agreement with experimental value of 3.44 micro(B). At antiferromagnetic phase, the net magnetic moment is 0.69 micro(B), in which the contribution from the net spin moment is 0.09 micro(B).

The reaction mechanism for the ORR on Fe–N3-Gra is investigated theoretically. Our results indicate that the ORR is a direct four-electron process, and the kinetically most favorable pathway is O2 hydrogenation.

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The structural stability, electronic, and mechanical properties of MoN were investigated by use of the density functional theory. Nine structures were considered, i.e., hexagonal

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The effect of electric field applied and Mg2+ doped on formation of calcium carbonatescale in circulating cooling water is investigated by using home-made experimental device, which can simulate the scaleof formationin local power plant. The results showthat high-voltage electrostatic fields and magnesium ions can inhibit scale growthin circulating cooling water. When the magnesium ion concentration is 4 mmol/L, the scale inhibition effect is the best under the action of the electric field (6 kV), and its scale inhibition rate can reach 44.56%. Meanwhile, some phenomenonare explained and confirmed by the results of first-principles calculations. The calculated shear modulus of aragonite is greater than that of calcite. This might be used to explain that aragonite is easier to adhere to the heat exchange surface. This is in good agreement with experimental results. Calcite has better anti-scaling property than aragonite. The crystal structure after physical water treatment is blunt, and the untreated crystal structure is sharp.