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A periodic-layered structure was observed in solid-(Cr, Fe)2B/liquid-Al diffusion couple at 750 &deg, C. The interface morphology, the reaction products, and the potential formation mechanism of this periodic-layered structure were investigated using an electron probe microanalyzer (EPMA), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and energy-dispersive spectroscopy (EDS). The results indicate that the reaction between (Cr, Fe)2B and liquid Al is a diffusion-controlled process. The formation of intermetallics involves both the superficial dissolution of Fe and Cr atoms and the inward diffusion of Al at the interface. The layered structure, as characterized by various experimental techniques, is alternated by a single FeAl3 layer and a (FeAl3 + Cr3AlB4) dual-phase layer. A potential mechanism describing the formation process of this periodic-layered structure was proposed based on the diffusion kinetics based on the experimental results.

In this study, a high aluminum and chromium Fe-B-C coating was prepared using laser cladding on 2Cr13 steel substrate. The microstructure, microhardness, and wear resistance of the high aluminum and chromium Fe-B-C coating were investigated. The results show that this dense coating possesses good metallurgical bond with the substrate. The microstructure is mainly composed of &alpha, (Fe, Cr, Al) lath martensite, orthorhombic M2B boride, orthogonal M3C2, and orthorhombic M7C3 carbides. The microhardness of the coating can reach 620 HV which is 3.3-times higher than that (190 HV) of the substrate. The coating shows a lower friction coefficient of 0.75 than that of the substrate (1.08). The wear rates of the substrate and the coating are 0.295 mg/min and 0.103 mg/min, respectively, indicating the coating exhibits excellent wear resistance. The wear mechanism transforms severe adhesive wear and abrasive wear of the substrate to slight abrasive wear of the coating. The results can provide technical support to improve the properties of the Fe-based laser cladded coating.

Ni-rich cathode material is one of the most promising material for Li-ion batteries (LIBs) in portable power and electric vehicles. However, how to recycle waste LIBs cathode materials is very important for environmental protection and resource utilization. LiNi0.6Co0.2Mn0.2O2 cathode materials were prepared by sol–gel combustion method Using waste LIBs cathode materials as raw materials. The effect of different gels on the crystal structure and morphology of LiNi0.6Co0.2Mn0.2O2 were studied by X-ray diffraction and scanning electron macroscopy. The electrochemical properties were investigated by charge–discharge testing, cyclic voltammetry and electrochemical impedance spectroscopy. The results showed that the samples contained some residual C and primary crystals have been formed during combustion stage. When glucose was used as gel regent, the sample has the good electrochemical properties with the initial discharge capacity of 176.9 mAh g−1, initial coulombic efficiency of 87.0% and discharge capacity retention rate of 95.8% after 50 cycles at 0.2 C rate. The results showed that the less the cation mixing, the more complete of hexagonal crystal structure, which induced the decrease of impedance resistance and good reversibility of redox reaction.

Additional file 1: Supplementary Figure 1 Representative flow cytometry staining of immunophenotypin. Supplementary Table 1 Correlations between Immune cell number and phenotype with age. Supplementary Table 2 Immune cell number and phenotype by CKD stage in age and sex-adjusted regression models in age-matched samples Supplementary Table 3 Effects of HbA1c on immune cell subsets in multivariable-adjusted regression models. Supplementary Table 4 Effects of glucose level on immune cell subsets in multivariable-adjusted regression model. Supplementary Table 5 Effects of duration of diabetes on immune cell subsets in multivariable-adjusted regression models. Supplementary Table 6 Effects of specific glucose-lowering medication usage on immune cell subsets in multivariable-adjusted regression models. Supplementary Table 7 Effects of CKD on immune cell subsets in age, sex and glucose level-adjusted regression models. Supplementary Table 8 Immune cell number and phenotype comparisons by albuminuria levels.

Effective oxidation control of metal materials is a long-standing challenge. Here we show a new strategy for oxidation control induced by nanoparticles (NPs). The results demonstrate that the in situ formed NPs can promote the formation and growth of a continuous and dense protective oxide scale while enhancing its adhesion with the matrix. Furthermore, the assembly of NPs on the grain boundaries (GBs) and phase boundaries (PBs) can be effective in stifling the inward diffusion of oxygen ions and the outward diffusion of cations. The effectiveness of this approach is verified in FeCr alloys in high temperature conditions. Our approach can break through the inherent limitations of conventional alloying treatment, e.g. the detrimental element interaction, the high costs and limited availability of noble metals and rare earth elements, which may pave a new avenue for the remarkable improvement in the oxidation resistance of metal materials.

In this work, in situ nanoparticles (TiB2 and TiC) can be demonstrated to induce significant improvement in the oxidation resistance of Fe-12 wt.%Cr-3.5 wt.%B alloys. To unravel the roles of nanoparticles in the anti-oxidation of Fe-12 wt.%Cr-3.5 wt.%B alloys, samples with various nanoparticle contents were synthesized to investigate their oxidation resistance. Results show that nanoparticles facilitate the formation of a continuous and dense Cr2O3 protective film and enhance its adhesion with the matrix. Furthermore, the nanoparticle assembly on the surface of borides can inhibit the inward diffusion of oxygen ions and the outward diffusion of cations, thereby effectively controlling the growth of oxide scales.