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A general approach is reported to fabricate a series of single‐phase 2:17‐type rare‐earth cobalt (RE2Co17, RE = Y, Ce, Pr, Nd, and Gd) nanoalloys by precisely controlled calcium thermic reduction of amorphous RE‐Co precursors. High‐purity hexagonal RE2Co17 phases are formed without the precipitation of Co and the other RE‐Co phases through the accurately manipulated co‐reduction of the two ions, which avoids the disadvantages of the impurity or second phases for RE metal alloys. RE2Co17/graphite nanostructures constructed with flower‐like RE2Co17 nanoalloys superficially decorated with nanosized graphite are further fabricated by introducing graphene oxides into the co‐reduction process. Compared with traditional magnetic planar‐anisotropy RE2Co17 alloys, the preserved high saturation magnetization (51.2–102.9 A m2 kg−1) and unusually increased coercivity (152–310.5 Oe) are achieved in these graphite‐decorated RE2Co17 nanoalloys. Moreover, these RE2Co17/graphite nanostructures exhibit good microwave absorption with an applied frequency range of 11.76–18 GHz, which shows their potential applications as new‐type Ku‐band electromagnetic materials. This work provides a facial way for the large‐scale production for varieties of single‐phase 2:17‐type RE‐Co nanoalloys and expands their application fields by constructing novel composite structures. [ABSTRACT FROM AUTHOR]

With the increasingly serious drug resistance of Acinetobacter baumannii, there is an increasingly urgent need for new antibacterial drugs. Phage lysin PlyAB1 has a bactericidal effect on drug‐resistant A. baumannii, which has the potential to replace antibiotics to fight infection caused by A. baumannii. However, its application is limited by its thermal stability and lytic activity. To solve these problems, molecular dynamics (MD) simulations combined with Hotspot wizard 3.0 were used to identify key residue sites affecting thermal stability, and evolutionary analysis combined with multiple sequence alignment was used to identify key residue sites affecting lytic activity. Four single‐point variants with significantly increased thermal stability and four single‐point variants with significantly lytic activity were obtained, respectively. Furthermore, by superimposing mutations, we obtained three double‐point variants, G100Q/K69R, G100R/K69R, and G100K/K69R, with significantly improved thermal stability and improved lytic activity. At 45°C, the lytic activity and half‐life of the optimal variant G100Q/K69R were 1.51‐ and 24‐fold higher than those of the wild PlyAB1, respectively. These results deepen our understanding of the structure and function of phage lysin and contribute to the application of phage lysin in antibiotic substitution. [ABSTRACT FROM AUTHOR]

Plastic waste is rapidly accumulating in the environment and becoming a huge global challenge. Many studies have highlighted the role of microbial metabolic engineering for the valorization of polyethylene terephthalate (PET) waste. In this study, we proposed a new conceptual scheme for upcycling of PET. We constructed a multifunctional Pseudomonas putida KT2440 to simultaneously secrete PET hydrolase LCC, a leaf-branch compost cutinase, and synthesize muconic acid (MA) using the PET hydrolysate. The final product MA and extracellular LCC can be separated from the supernatant of the culture by ultrafiltration, and the latter was used for the next round of PET hydrolysis. A total of 0.50 g MA was produced from 1 g PET in each cycle of the whole biological processes, reaching 68% of the theoretical conversion. This new conceptual scheme for the valorization of PET waste should have advantages over existing PET upcycling schemes and provides new ideas for the utilization of other macromolecular resources that are difficult to decompose, such as lignin. [ABSTRACT FROM AUTHOR]

Low mechanical performance is the key technical problem for metal-based soft magnetic composites (SMCs) with core-shell structures needed to be urgently resolved for their actual applications due to the limitation of their conventional preparation methods. In this work, dense sintered Al 2 SiO 5 ceramic layers have been in situ formed and entirely coated on the surfaces of high-purity deformed Fe particles via a low-temperature solid-phase reaction between initially-coated amorphous nano-Al 2 O 3 and nano-SiO 2 to obtain a new ceramic-reinforced Fe/Al 2 SiO 5 SMCs. The fully-densified Fe/Al 2 SiO 5 SMCs exhibit a high transverse rupture strength value of 120 MPa, which exceeds those for most of present metal-based SMCs. These ceramic-coated Fe-based composites also show strong corrosion resistance in water-air and salt-water conditions due to the anti-corrosion Al 2 SiO 5 coating layers completely isolating the deformed Fe particles from the corrosion environments. Good magnetic performance is maintained in these high-strength and corrosion-resistant Fe/Al 2 SiO 5 SMCs due to the suitable thickness of Al 2 SiO 5 coating layers, which promises their broad application prospects for high-power electromagnetic devices in critical environments. Moreover, the fabrication for fully-densified functional metal-ceramic composites by a nanoscale solid-state reaction coating method in this work can provide a new insight for the research and applications of the other new-type metal-based composites. [Display omitted] • New ceramic-reinforced Fe/Al 2 SiO 5 soft magnetic composites have been fabricated. • A high TRS value of 120 MPa is obtained for Fe/AlSiO 5 composites. • Fe/AlSiO 5 composites show strong corrosion resistance. • Good soft magnetic properties were maintained in the composites. [ABSTRACT FROM AUTHOR]

Polyolefin plastics are a group of polymers with C-C backbone that have been widely used in various areas of daily life. Due to their stable chemical properties and poor biodegradability, polyolefin plastic waste continues to accumulate worldwide, causing serious environmental pollution and ecological crises. In recent years, biological degradation of polyolefin plastics has attracted considerable attention. The abundant microbial resources in the nature offer the possibility of biodegradation of polyolefin plastic waste, and microorganisms capable of degrading polyolefin have been reported. This review summarizes the research progress on the biodegradation microbial resources and the biodegradation mechanisms of polyolefin plastics, presents the current challenges in the biodegradation of polyolefin plastics, and provides an outlook on future research directions.