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Drosophila suzukii (Diptera: Drosophilidae), spotted-wing drosophila, poses a significant threat to soft-skinned fruit crops in the Americas, Europe, Africa, and Oceania, as well as in Asia. The application of chemical insecticides is the primary control strategy for D. suzukii; however, resistance has developed with the indiscriminate use of chemical insecticides. Essential oils, considered potential alternatives to pesticidal strategies, exhibit potent toxic and sublethal behavioral effects against numerous pests, including D. suzukii. Clary sage oil repels a variety of agricultural and household pests; however, whether it has a repellent effect against D. suzukii remains unknown. Here, we found that clary sage oil exhibited dose-dependent repellency against D. suzukii adults in a T-maze assay, a two-choice assay and a two-choice attraction assay. Also, clary sage oil showed a significant repellent effect against D. suzukii larvae. Next, we explored the chemical constituents of clary sage oil by GC-MS and identified two major constituents, linalyl acetate (40.03%) and linalool (23.02%). Furthermore, the behavioral assays of linalyl acetate and linalool showed that both compounds conferred comparable repellency against D. suzukii adults and larvae. Finally, we found clary sage oil, linalyl acetate, and linalool elicited EAG responses in D. suzukii, especially clary sage oil, suggesting the repellency was mediated by the olfactory system. These findings indicate that D. suzukii shows olfactory-based behavioral avoidance of clary sage oil, linalyl acetate, and linalool. Clary sage oil and its major constituents may be possible alternatives in the management of D. suzukii.

The low hardness and poor wear resistance of laser-cladding 316L stainless steel impose significant constraints on its practical applications. In this study, a strategy for strengthening laser-cladding 316L stainless steel with WMoTaNb refractory high-entropy alloy as a reinforcement material is proposed. The results confirm that the coating primarily comprises a body-centered cubic (BCC) Fe-based solid solution, a network-distributed hexagonal Fe2X (X = W, Mo, Ta, and Nb) Laves phase, and a diffusely distributed face-centered cubic (FCC) (Ta, Nb)C phase. The Fe-based solid solution distributes along columnar and fine dendrites, while the Laves phase and (Ta, Nb)C phase are in the inter-dendrites. The presence of a significant number of network Laves phases exhibiting high strength and hardness is the primary factor contributing to the enhancement of coating microhardness. The hardness of the composite coating is increased by nearly twice compared to that of the 316L coating, resulting in an improved wear resistance. The present work can shed light on designing and fabricating 316L stainless steel coating with enhanced hardness and wear resistance.

La0.6Ca0.4Co1–xFexO3–d in its various compositions has proven to be an excellent CO2-resistant oxygen transport membrane that can be used in plasma-assisted CO2 conversion. With the goal of incorporating green hydrogen into the CO2 conversion process, this work takes a step further by investigating the compatibility of La0.6Ca0.4Co1–xFexO3–d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO2 reduction process into green fuels, like methanol. This requires the La0.6Ca0.4Co1–xFexO3–d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La0.6Ca0.4Co1–xFexO3–d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La0.6Ca0.4Co0.2Fe0.8O3–d membranes. The La0.6Ca0.4Co0.2Fe0.8O3–d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

The effects of nanosecond pulsed laser processing (NPLP) on the surface morphology, microstructure, and corrosion resistance properties of Fe-based metallic glass coating were investigated. It was found that after pulsed laser processing, the metallic glass coating retained its amorphous structure; however, cracks were generated on the top of the coating. The thickness of the remelted zone reached about 30 μm, and the microstructure became denser after the remelting process. In addition, most of the original defects in the coating disappeared. The corrosion resistance of Fe-based metallic glass coating after NPLP was increased in 3.5 wt.% NaCl solution.

Constructing novel van der Waals heterostructures (vdWHs) is one of the effective methods for expanding the properties and applications of single materials. In this contribution, a blue phosphorene (Blue P)/MoSi2N4 vertical bilayer vdWH was constructed, and its crystal and electronic structures as well as optical properties were systematically studied via first principles calculation. It was found that the Blue P/MoSi2N4 vdWH with good thermal and dynamic stabilities belongs to the type-II indirect bandgap semiconductor with the bandgap of 1.92 eV, which can efficiently separate electrons and holes. Additionally, the two band edges straddle the redox potential of water, and the charge transfer follows the Z-scheme mode, making the Blue P/MoSi2N4 vdWH a promising catalyst of hydrogen production through splitting water. Meanwhile, the Blue P/MoSi2N4 vdWH has higher optical absorption than its two component monolayers. Both the external electric field and vertical strain can easily tailor the bandgap of Blue P/MoSi2N4 vdWH while still preserving its type-II heterostructure characteristics. Our proposed Blue P/MoSi2N4 vdWH is a promising photovoltaic two-dimensional material, and our findings provided theoretical support for the related experimental exploration.

Dense, H2- and CO2-resistant, oxygen-permeable 40 wt % Ce0.9Pr0.1O2–δ–60 wt % NdxSr1−xFe0.9Cu0.1O3−δdual-phase membranes were prepared in a one-pot process. These Nd-containing dual-phase membranes have up to 60% lower material costs than many classically used dual-phase materials. The Ce0.9Pr0.1O2−δ–Nd0.5Sr0.5Fe0.9Cu0.1O3−δ sample demonstrates outstanding activity and a regenerative ability in the presence of different atmospheres, especially in a reducing atmosphere and pure CO2 atmosphere in comparison with all investigated samples. The oxygen permeation fluxes across a Ce0.9Pr0.1O2−δ–Nd0.5Sr0.5Fe0.9Cu0.1O3−δ membrane reached up to 1.02 mL min−1 cm−2 and 0.63 mL min−1 cm−2 under an air/He and air/CO2 gradient at T = 1223 K, respectively. In addition, a Ce0.9Pr0.1O2–δ–Nd0.5Sr0.5Fe0.9Cu0.1O3–δ membrane (0.65 mm thickness) shows excellent long-term self-healing stability for 125 h. The repeated membrane fabrication delivered oxygen permeation fluxes had a deviation of less than 5%. These results indicate that this highly renewable dual-phase membrane is a potential candidate for long lifetime, high temperature gas separation applications and coupled reaction–separation processes.

The significance of small-strain stiffness (Gmax) of saturated composite soils are still of great concern in practice, due to the complex influence of fines on soil fabric. This paper presents an experimental investigation conducted through comprehensive bender element tests on Gmax of marine silty sand. Special attention is paid to the influence of initial effective confining pressure ( σ c 0 ′ ), global void ratio (e) and fines content (FC) on Gmax of a marine silty sand. The results indicate that under otherwise similar conditions, Gmax decreases with decreasing e or FC, but decreases with increasing FC. In addition, the reduction rate of Gmax with e increasing is not sensitive to σ c 0 ′ , but obviously sensitive to changes in FC. The equivalent skeleton void ratio (e*) is introduced as an alternative state index for silty sand with various FC, based on the concept of binary packing material. Remarkably, the Hardin model is modified with the new state index e*, allowing unified characterization of Gmax values for silty sand with various FC, e, and σ c 0 ′ . Independent test data for different silty sand published in the literature calibrate the applicability of this proposed model.