This study provides a novel method to prepare metal-ceramic composites from magnetically selected iron ore using microwave heating. By introducing three different microwave susceptors (Activated Carbon, SiC, and a mixture of Activated Carbon and SiC) during the microwave process, effective control of the ratio of metallic and ceramic phases has been achieved easily. The effects of the three susceptors on the microstructure of the metal-ceramics and the related reaction mechanisms were also investigated in detail. The results show that the metal phase (Fe) and ceramic phase (Fe2SiO4, FeAl2O4) can be maintained, but the metal phase to ceramic phase changed significantly. In particular, the microstructures appeared as well-distributed nanosheet structures with diameters of ~400 nm and thicknesses of ~20 nm when SiC was used as the microwave susceptor.

The cavitation behavior of cryogenic liquids in the field of cryogenic engineering is distinct, showcasing fundamental differences from the cavitation behavior observed in ambient temperature water. Cavitation occurrence imposes severe limitations on the operational stability of cryogenic media transportation equipment, leading to safety concerns and increased manufacturing costs. Investigating the spatiotemporal characteristics of cavitation in cryogenic fluids holds significant value for both academia and engineering. The complexity of cavitation in cryogenic fluids primarily manifests through the coupled effects of thermodynamics, vortices, and bubbles during the cavitation process. In order to further explore the coupling mechanism, numerical simulations employing the Delayed Detached Eddy Simulation (DDES) turbulence model and Sauer-Schnerr cavitation model are conducted to validate the accuracy of the numerical calculations using the Hord experiment hydrofoil as a benchmark. Subsequently, the unsteady cavitation flow of liquid nitrogen around the NACA 0015 hydrofoil is simulated by the same numerical calculation method. The results indicate that the simulated results best coincide with experimental results when the bubble number density in the Sauer-Schnerr cavitation model reaches 108. The upstream development of the re-entrant jet under the driving force of inverse pressure gradient is the fundamental reason for the detachment of the primary cavitation zone. Under the same inflow cavitation number, the thermodynamic effect significantly inhibits the generation of bubbles and changes the range of the inverse pressure gradient, thus affecting the separation behavior of the primary cavitation zone.

The microstructure and solidification behavior of nickel based GTD222 superalloy at different cooling rates are studied. The solidification of the GTD222 superalloy proceeds as follows: L→L+γ, L→L+γ+MC, L→L+(γ/γ ′)-Eutectic and L→η phase. The temperature of liquidus of GTD222 superalloy is 1360 °C while the solidus is slightly lower at 1310 °C, which due to the alloying elements redistribution. It was found that the dendrite arm spacing of the alloy decreased with the increase of cooling rate (From 200 μm at 2.5 K/min to 100 μm at 20 K/min).

Bees (Apoidea), the largest and most crucial radiation of pollinators, play a vital role in ecosystem balance. Transposons are widely distributed in nature and are important drivers of species diversity. However, transposons are rarely reported in important pollinators such as bees. Here, we surveyed 37 genomes in Apoidea, annotated the pogo and Tc1/mariner transposons in the genome of each species and performed a phylogenetic analysis to determine their overall distribution. The pogo and Tc1/mariner families showed high diversity and low abundance in the 37 species, and their proportion was significantly higher in solitary bees than in social bees. DD34D/mariner was found to be distributed in almost all species and was found in Apis mellifera, Apis mellifera carnica, Apis mellifera caucasica and Apis mellifera mellifera and Euglossa dilemma may still be active. Using horizontal transfer analysis, we found that DD30D/Tigger, DD33D/Tigger and DD34D/mariner may have experienced horizontal transfer events. The current study displayed the evolution profiles (including diversity, activity, and abundance) of the pogo and Tc1/mariner transposons across 37 species of Apoidea. Our data revealed their contributions to the genomic variations across these species and facilitated in understanding of the genome evolution of this lineage.