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Tobacco black shank (TBS) and tobacco root black rot (TRBR) are two of the most devastating tobacco soil‐borne diseases that threaten sustainable tobacco planting. This study investigated the effects of Trichoderma sp. and a resistance inducer (RI) extracted from traditional Chinese medicine, individually or in combination, on the control of TBS and TRBR. The results showed that the application of Trichoderma sp. and RI, individually or in combination, significantly controlled the two soil‐borne diseases by significantly affecting the bacterial, but not fungal, Shannon and Simpson diversity indexes. The disease indexes of TBS and TRBR in integrated application management were the lowest, resulting in the highest potassium contents in the tobacco leaves. The control efficacies of TBS and TRBR in the integrated application treatment were 71.52 ± 1.43% and 68.33 ± 0.69%, respectively. The integrated treatment altered the composition of the rhizosphere soil microbial community. The bacterial community, but not the fungal community, of the control treatment was separated from those of other treatments. The relative abundance of bacteria involved in chemoheterotrophy and fermentation in the control treatment increased, whereas that of bacteria involved in nitrification and aerobic ammonia oxidation decreased compared with the other treatments. Importantly, the application of Trichoderma sp. and RI, individually or in combination, clearly increased the relative abundance of saprotrophic fungi in contrast to the control treatment, while decreasing that of pathotrophic fungi. Our study suggests that a suitable integrated application of bioagents and RI has synergistic effects on the suppression of two tobacco soil‐borne diseases by altering the rhizosphere microbiome composition in the field. [ABSTRACT FROM AUTHOR]

The sixth-generation wireless communication (6G) extends the electromagnetic pollution up to the terahertz band. The two-dimensional titanium carbide of intercalated structure Ti3C2Tx MXene attracts much attention because it exhibits high terahertz electromagnetic interference (EMI) shielding effectiveness (SE) due to the large intrinsic electrical conductivity as well as few-atom monosheet thickness. Scientists worldwide are making continuous efforts to optimize the MXene structures for EMI shielding application. Innovatively, we demonstrate a chemical method to bend the nanoflake by grafting two types of alkane, octane (C8H18) and dodecane (C12H26), onto the surface terminals. The chain length of alkane exceeds the bond length of surface functionalities Tx (=O, −OH, −F) to introduce intrananoflake and internanoflake strains into Ti3C2Tx MXene. The nanoflake's deformation leads to Raman peak redshift and broader line width. The element distribution shows that the alkane increases the oxygen–fluorine ratio of Ti3C2Tx MXene from 3:2 to 3:1 (Ti3C2Tx-C8H18) and even up to 4:1 (Ti3C2Tx-C12H26). Electronic microscopy (SEM/TEM) shows obvious edge-fold and tensile/compressive deformation of the nanoflake. The EMI SE of Ti3C2Tx-C12H26 achieves 35 dB, which is higher than those of Ti3C2Tx-C8H18 (26 dB) and Ti3C2Tx MXene (22 dB). The alkane grafting increases the absorption coefficient of the MXene thin film by more than 50% but has negligible contribution to the refractive index. Meanwhile, the conductivity of Ti3C2Tx-C8H18 MXene is over twice higher than that of Ti3C2Tx MXene, whereas the conductivity of Ti3C2Tx-C12H26 is three times higher than that of Ti3C2Tx MXene. The nanoflake curvature of alkane grafted Ti3C2Tx MXene enlarges the specific surface area and causes topological defects, which increase the absorption as well as the conductivity so that the terahertz EMI SE is enhanced correspondingly. The realization of Ti3C2Tx MXene of curved nanoflake for the enhancement of terahertz EMI SE is valuable for 6G electromagnetic protection. [ABSTRACT FROM AUTHOR]

Laser-based additive manufacturing has garnered significant attention in recent years as a promising 3D-printing method for fabricating metallic components. However, the surface roughness of additive manufactured components has been considered a challenge to achieving high performance. At present, the average surface roughness (Sa) of AM parts can reach high levels, greater than 50 μm, and a maximum distance between the high peaks and the low valleys of more than 300 μm, which requires post machining. Therefore, laser polishing is increasingly being utilized as a method of surface treatment for metal alloys, wherein the rapid remelting and resolidification during the process significantly alter both the surface quality and subsurface material properties. In this paper, the surface roughness, microstructures, microhardness, and wear resistance of the as-received, continuous wave laser polishing (CWLP), and pulsed laser polishing (PLP) processed samples were investigated systematically. The results revealed that the surface roughness (Sa) of the as-received sample was 6.29 μm, which was reduced to 0.94 μm and 0.84 μm by CWLP and PLP processing, respectively. It was also found that a hardened layer, about 200 μm, was produced on the Ti6Al4V alloy surface after laser polishing, which can improve the mechanical properties of the component. The microhardness of the laser-polished samples was increased to about 482 HV with an improvement of about 25.2% compared with the as-received Ti6Al4V alloy. Moreover, the coefficient of friction (COF) was slightly reduced by both CWLP and LPL processing, and the wear rate of the surface layer was improved to 0.790 mm3/(N∙m) and 0.714 mm3/(N∙m), respectively, under dry fraction conditions. [ABSTRACT FROM AUTHOR]