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2D multiferroics with magnetoelectric coupling combine the magnetic order and electric polarization in a single phase, providing a cornerstone for constructing high-density information storages and low-energy-consumption spintronic devices. The strong interactions between various order parameters are crucial for realizing such multifunctional applications, nevertheless, this criterion is rarely met in classical 2D materials at room-temperature. Here an ingenious space-confined chemical vapor deposition strategy is designed to synthesize atomically thin non-layered ε-Fe

Epitaxial growth and controllable doping of wafer-scale atomically thin semiconductor single crystals are two central tasks to tackle the scaling challenge of transistors. Despite considerable efforts have been devoted, addressing such crucial issues simultaneously under two-dimensional (2D) confinement is yet to be realized. Here we design an ingenious epitaxial strategy to synthesize record-breaking 4-inch Fe-doped transition-metal dichalcogenides (TMDCs) single crystals on industry-compatible c-plane sapphire without miscut angle. Atomically thin transistors with the highest recorded electron mobility (~231 cm2 V−1 s−1) and remarkable on/off current ratio (~109) are fabricated based on 4-inch Fe-MoS2 single crystals, due to the ultralow contact resistance (~489 Ω µm) and subthreshold swing (~95 mV dec−1). In-depth characterizations and theoretical calculations reveal that the introduction of Fe significantly decreases the formation energy of parallel steps on sapphire surfaces and contributes to the edge-nucleation of unidirectional alignment TMDCs domains (>99%), as well as the modulation of band structures. This work represents a substantial leap in terms of bridging synthesis and doping of wafer-scale 2D semiconductor single crystals without the need for substrate miscut, which should promote the further device downscaling and extension of Moore’s law.

Tin selenide (SnSe

2D semiconductors are emerging as plausible candidates for next-generation "More-than-Moore" nanoelectronics to tackle the scaling challenge of transistors. Wafer-scale 2D semiconductors, such as MoS

Turbulence plays a key role in the aerospace design process. It is common that incompressible and compressible flows coexist in turbulent flows around aerospace vehicles. However, most upwind schemes in compressible solvers were designed to capture shock waves and have been proved to have difficulties in predicting low-speed flow regions. In order to overcome this defect, many all-speed schemes have been proposed. This paper investigates the properties of the all-speed schemes when applying to Reynolds averaged Navier–Stokes simulations with important low-speed features. First, the correctness of our code is validated. Then four test cases are adopted to evaluate the scheme performance, including a Mach 2.85 compression ramp, the NACA 4412 airfoil, a Mach 2.92 ramped cavity and a three-dimensional surface-mounted cube. Grid-converged results from the all-speed schemes show good agreement with the experimental data and remarkable improvement when compared to standard upwind schemes. Moreover, different from the traditional preconditioning methods, the all-speed schemes are simple to realize and free from the cut-off strategy or any problem-dependent parameter. Therefore, they are expected to be widely implemented into compressible solvers and applied to all-speed turbulent flow simulations.

Summary In this paper, we propose a simple robust flux splitting method for all-speed flows with low dissipation. Following the Toro-Vazquez splitting, the inviscid flux is split into the convective and the pressure parts first. Then, we apply the Harten-Lax-van Leer (HLL) algorithm to each parts with low dissipation modification. Here, the modification improves the method with accurately resolving contact discontinuity and high resolution for low speed flows. Several carefully chosen numerical tests are investigated, and the results show that the proposed scheme is capable of resolving contact discontinuity, robust against the shock anomaly and accurate at all-speeds. Because of these properties, it is expected to be widely applied to all-speed flow studies. Copyright © 2016 John Wiley & Sons, Ltd.

Inspired by the high adhesiveness of the electrospun fiber, we propose a method to fabricate multi-scale heterogeneous hump-on-string fiber via the adsorption of nanoparticles, the NPCTi which is the hydrolysate of titanium tetrachloride (TiCl4) and the nanoparticles containing Al (NPCAl) which is produced by the hydrolysis of Trimethylaluminium (TMA, Al(CH3)3). The water collection efficiency of the fibers can be easily controlled via changing not only the size of the beads but also the ratio of the Ti and Al. In addition, we introduce a computational fluid dynamics (CFD) simulation to show the pressure distribution of on the surface of the fibers, which gives another explanation regarding the high water collection efficiency.

Partially-averaged Navier-Stokes (PANS) method, as a bridging method between Reynolds-averaged Navier-Stokes (RANS) and direct numerical simulation (DNS), has attracted many researchers' attentions in recent years. In this paper, PANS is extended to the simulations of a jet injected into a supersonic crossflow. A dynamic function of the resolution control parameter f k (unresolved-to-total ratio of kinetic energy) is adopted. Numerical results are compared to the experimental data and the performance of PANS is evaluated. The predictions of dynamic f k PANS overall agree well with the measurements and the instantaneous flow filed is provided. In addition, the distribution of f k is presented to have a better understanding of the method's scale resolving behavior throughout the computation domain. Current study has shown the capabilities and potential of PANS method for supersonic industrial flows.