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The 2319-Al alloy is widely used in aviation industry. The crack-free 2319 alloy thin-walled sample was fabricated utilizing the laser-CMT composite additive manufacturing technique, achieving a material utilization rate of 96.43%. The impact of deposition parameters and deposition height on the microstructure and mechanical properties was studied. The microhardness of the additive manufacturing samples exhibited a gradual decrease from construction direction, with values reaching 90 HV, 78 HV, and 72 HV, respectively. The tensile property also exhibited a gradual decrease from the bottom to the top; the highest tensile strength was 296 MPa. The grain size along the construction direction of the deposited sample gradually increased, exhibiting respective sizes of 34.7 um, 36.6 um, and 45.7 um. With the increase in the height of the second phase, the segregation at the grain boundary is intensified, and as the size inside the grain increases, the corresponding density decreases. The good laser-CMT composite additively manufactured 2319 aluminum alloy samples could be obtained under the optimized deposition parameters. [ABSTRACT FROM AUTHOR]

Due to their unique tubular and spiral structure, graphene and graphene oxide nanoscrolls (GONS) have shown extensive applications in various fields. However, it is still a challenge to improve the optoelectronic application of graphene and GONS because of the zero bandgap of graphene. Herein, ammonium tetrathiomolybdate ((NH4)2MoS4) was firstly wrapped into the ((NH4)2MoS4@GONS) by molecular combing the mixture of (NH4)2MoS4 and GO solution on hydrophobic substrate. After thermal annealing, the (NH4)2MoS4 and GO were converted to MoS2 nanosheets and reduced GO (RGO) simultaneously, and, thus, the MoS2@RGONS was obtained. Raman spectroscopy and high-resolution transmission electron microscopy were used to confirm the formation of MoS2 nanosheets among the RGONS. The amount of MoS2 wrapped in RGONS increased with the increasing height of GONS, which is confirmed by the atomic force microscopy and Raman spectroscopy. The as-prepared MoS2@RGONS showed much better photoresponse than the RGONS under visible light. The photocurrent-to-dark current ratios of photodetectors based on MoS2@RGONS are ~570, 360 and 140 under blue, red and green lasers, respectively, which are 81, 144 and 35 times of the photodetectors based on RGONS. Moreover, the MoS2@RGONS-based photodetector exhibited good power-dependent photoresponse. Our work indicates that the MoS2@RGONS is expected to be a promising material in the fields of optoelectronic devices and flexible electronics. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenide (TMD) nanosheets (e.g., MoS2) with metallic phase (1T or 1T´ phase) have been proven to exhibit superior performances in various applications as compared to their semiconducting 2H-phase counterparts. However, it remains unclear how the crystal phase of 2D TMD nanosheets affects their sonodynamic property. In this work, we report the preparation of MoS2 nanosheets with different phases (metallic 1T/1T´ or semiconducting 2H) and exploration of its crystal-phase effect on photothermal-enhanced sonodynamic antibacterial therapy. Interestingly, the defective 2D MoS2 nanosheets with high-percentage metallic 1T/1T´ phase (denoted as M-MoS2) present much higher activity towards the ultrasound-induced generation of reactive oxygen species (ROS) as compared to the semiconducting 2H-phase MoS2 nanosheets. More interestingly, owing to its metallic phase-enabled strong absorption in the near-infrared-II (NIR-II) regime, the ultrasound-induced ROS generation performance of the M-MoS2 nanosheets can be further enhanced by the photothermal effect under a 1064 nm laser irradiation. Thus, after modifying with polyvinylpyrrolidone, the M-MoS2 nanosheets can be used as an efficient sonosensitizer for photothermal-enhanced sonodynamic bacterial elimination under ultrasound treatment combining with NIR-II laser irradiation. This study demonstrates that metallic MoS2 nanosheets can be used as a promising sonosensitizer for antibacterial therapy, which might be also promising for cancer therapies. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effect of Fe/Ni addition on phase separated behavior in Cu75Co25 was investigated. [•] Particle size distribution in Cu75Co25 − x M x (M=Fe, Ni and x =1, 5) alloys was reported. [•] Small amounts Fe/Ni addition has similar effect to that of alter undercooling in Cu–Co alloy. [ABSTRACT FROM AUTHOR]