Fe 3 O 4 @CNF anode material for Li-ion batteries (LIBs) was designed and fabricated using lyotropic cellulose acetate as the carbon nanofiber (CNF) phase and Fe(acac) 3 as the Fe 3 O 4 phase through the electrospinning approach. Because the CNFs could retard the change of Fe 3 O 4 volume during the electrochemical cycling and improve the electrical conductivity and the introduction of Fe 3 O 4 could offer a larger specific surface area and more mesopores to promote electrolyte penetration and Li + diffusion, the Fe 3 O 4 @CNFs electrode showed high reversible capacities (RCs) of 773.6 and 596.5 mAh g −1 after 300 cycles and capacity residuals of 98.0 and 99.0% at high current densities 1 and 2 A g −1 , respectively. This simple method to fabricate Fe 3 O 4 @ CNFs composite as anode material can be widely applied to fabricate metal oxides and bio-carbon composite nanofibers for highperformance energy storage materials.

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In this work, a novel ultrahigh-strength Al-10Zn-3.5Mg-1.5Cu alloy was fabricated by powder metallurgy followed by hot extrusion. Investigations on microstructural evolution and mechanical properties of the fabricated samples were carried out. The results show that the grain size of sintered samples matches with the powder particles after ball milling. The relative densities of sintered and hot extruded samples reach 99.1% and 100%, respectively. Owing to the comprehensive mechanism of grain refinement, aging and dispersion strengthening, the ultimate tensile strength, yield strength and elongation of the Al-10Zn-3.5Mg-1.5Cu alloy after hot extrusion and subsequent heat treatment achieve 810 MPa, 770 MPa and 8%, respectively.

In this work, Al-Zn-Mg-Cu powders containing 0.15 and 0.33 wt % oxygen were utilized to prepare high-strength aluminum alloys through the process of cold isostatic pressing, sintering, hot extrusion, and heat treatment. Microstructural and mechanical properties at elevated temperatures of 250, 350, and 450 °C were investigated by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and high-temperature tensile tests. Results showed that the tensile strengths of the obtained Al-Zn-Mg-Cu alloys with 0.15 wt % oxygen were 185, 46, and 18 MPa at 250, 350, and 450 °C, respectively. When the oxygen content of Al-Zn-Mg-Cu alloy rose to 0.33 wt %, the tensile strengths at the corresponding temperature reached up to 205, 68, and 25 MPa, respectively. The excellent high-temperature performance could be attributed to double hindrance to dislocation motion and grain boundary migration by a large amount of nano γ-Al2O3 created by the in-creased oxygen, thereby resulting in fine grains even at high temperatures.