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This work aimed to explore the effect of cBN (cubic boron nitride) content on the microstructures and wear-corrosion resistance of the CoCrFeNiTi0.8-xcBN (x = 0, 2, 4, 6 wt.%) particle-reinforced high-entropy alloy coatings. Laser cladding technology was used to prepare the coatings on TC18 substrate. The microstructures, volume wear rates and polarization curves were characterized. The results showed that the CoCrFeNiTi0.8-xcBN coatings had an optimal forming quality under the process parameters: laser power of 1500 W, scanning rate of 12 mm/s and overlapping rate of 60%. As the cBN content increased, plenty of TiN and TiB2 hard particles formed in situ in the coatings, significantly improved the wear resistance. As a result, the volume wear rate of CoCrFeNiTi0.8-6cBN was only 4.0% and 16.5% of that of TC18 substrate and CoCrFeNiTi0.8 coating, respectively; the wear mechanism changed from adhesive wear + oxidative wear to abrasive wear + oxidative wear gradually. Moreover, CoCrFeNiTi0.8-xcBN coatings can effectively inhibit the infiltration of corrosive media by dense organizational characteristics and the physical barrier effect of oxidation-protective films. After 480 h of neutral salt spray (NSS) test, the CoCrFeNiTi0.8-xcBN coatings exhibited excellent corrosion resistance, both of the appearance and protection rating reached level 10. Therefore, it can be used as the wear-corrosion-resistant coating for the TC18 substrate in a NSS environment. [ABSTRACT FROM AUTHOR]

Transitional metal oxides have attracted increasing attention as the most promising anode material for lithium-ion batteries (LIBs). However, due to the poor ionic conductivity and great structural changes in the process of Li+ insertion and extraction, the performance of the pristine materials in batteries still has a far way to go to satisfy requirements. In this article, using spherical ZIF-12 as a pyrolysis precursor, two Co3O4 hollow core-shell carbon nanocomposites (CHS@C and CHS@CG) were fabricated via a molecular precursor pyrolysis strategy. The synergistic effect of the yolk-shell hollow nanosphere structure shortens the diffusion path of ions, increases the contact area between the electrode and electrolyte, and provides a buffer space for the volume change in the electrochemical reaction. Both materials have excellent structural stability and good electrical conductivity. In comparison, the performance of CHS@CG is better, and the reversible specific capacity reaches 831 mAh·g−1 at 0.2 C after 400 cycles. In the galvanostatic charge–discharge process, the Coulombic efficiency reaches nearly 100%, exhibiting a good reversible cycle. The synthesis method of these electrode materials can provide a reference for making other energy storage equipments. [ABSTRACT FROM AUTHOR]

A laser-dressed V-type atom trapped in a two-mode optical cavity is investigated, which induces a SWAP gate on the two modes of the cavity. Two laser fields are imposed to interact with the atom dispersively, which leads to an effective interaction between two atomic excited states. The state of the atom prepared initially in the ground state keeps invariant, but the photon exchange between the two cavity modes occurs. Compared with the schemes (Lin et al. in Phys Rev A 77:064301, 2008 and Yan et al. in Quantum Inf Process 17:71, 2018) that use ∇ -type atoms, the present scheme is more practical, because usually the ∇ -type atom may be hardly obtained due to the dipole transition selection rule. In addition, the robustness of the SWAP gate against the pulse control error is strengthened by using time-dependent shaped pulses. The effect of the atomic spontaneous radiation and the photon loss is discussed by means of the numerical simulations. [ABSTRACT FROM AUTHOR]