The global warming promotes the steel industry to replace part of coke by injecting hydrogen-rich fuel into the blast furnace to reduce CO 2 emissions and energy consumption. In this paper, the injected hydrogen-rich fuels and effects of hydrogen-rich smelting on burden reduction and property evolution were introduced, and the hot events related to hydrogen metallurgy were summarized. Increasing hydrogen content changes the thermodynamic and kinetic conditions of chemical reactions, changing the reduction behaviour of iron oxides and affecting the burden properties evolution and soft melting behaviour. Correspondingly the coke solution loss alters due to more H 2 O existence. In addition, the temperature and gas flow distribution are altered, affecting the iron oxide reduction rate and efficiency of blast furnace operation process. At present, some hydrogen metallurgy projects have been launched, making expected progress, which provides reference and thinking for the large-scale industrial application of hydrogen in blast furnace.

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The effect of BaO on the viscosity of experimental slag with the CaO/SiO 2 ratio of 0.7 was studied based on the rotating cylinder method, and the structure evolution analysis was performed using Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and 27 Al MAS-NMR spectra. The results indicated that the viscosity of molten slag decreased gradually with BaO content rising from 0 wt.% and 5 wt.% due to the dominant effect of free O 2rather than Ba 2+ . The viscous flow activation energy (Eη) of molten slag was calculated, presenting a similar change trend with that of viscosity. The structure analysis demonstrated that, with the increasing BaO content, the [SiO 4 ]-tetrahedral structures and Si-O-Al bonds were destroyed due to an increase in the relative fraction of free oxygen (O 2-). For the Al-related structural units, the 27 Al magic angles spinning nuclear magnetic resonance ( 27 Al MAS NMR) spectra analysis illustrated that the concentration of [AlO 4 ] units reduced, whereas that of [AlO 5 ] and [AlO 6 ] units increased because of the increase of free oxygen and nonbridged oxygen (O 0 ). The results of structure analysis agreed well with the viscosity variations of experimental slag.

The Co nanowires with different diameters were prepared by pulsed electrodeposition into anodic alumina membranes oxide templates. The micrographs and crystal structures of nanowires were studied by FE-SEM, TEM, and XRD. Due to their cylindrical shape, the nanowires exhibit perpendicular anisotropy. The coercivity and loop squareness (Mr/Ms) of Co nanowires depend strongly on the diameter. Both coercivity and Mr/Ms decrease with increasing wire diameter. The behavior of the nanowires is explained briefly in terms of localized magnetization reversal.