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•Sintered Nd-Fe-B sludge was purified using a combination of physical and chemical methods to obtain purified sludge with a Nd2Fe14B phase.•Propose new strategies for ultra-short ...process recycling of a variety of sludges.•Break through the barrier of lower magnetic properties of regenerative magnets.•Low recycling cost and substantial reduction of recycling energy consumption.
The highly efficient and green recycling of sintered Nd-Fe-B sludge has emerged as a pressing concern in light of the escalating production of sludge. In this work, a novel ultra-short process strategy of purification-remixing incorporation is proposed for in-situ regeneration across several types of Nd-Fe-B sludges. The magnetic properties of the regenerated magnets are effectively restored by remixing the purified sludge at 30 wt% into customized high-remanence magnetic powder, followed by the adjustment of rare earth content to 30.5 % using rare earth-rich compounds. For magnets using 48SH sludge, the remanence and coercivity are recovered to 13.8 kG and 22.2 kOe, respectively, with recovery rates of 97 % and 108.3 %, which are almost as high as those of the original magnets. The temperature stability of the magnet is comparable to that of the original magnet as well. The comprehensive analysis attributes the attainment of high-performance to the repair and optimization of the microstructure, particularly focusing on the grain boundary phase.The ultra-short recovery process and the reuse of solvents in the purification phase minimize the total energy consumption and carbon emissions, and show great potential for green recycling for Nd-Fe-B sludge.
The regeneration of Nd-Fe-B sludge is of great practical significance for achieving the sustainable development and recycling of rare earth elements. In this study, the in-situ regeneration of sludge ...was realized at a lower temperature of 850 °C via the mechanochemical approach based on ball-milling and Ca-reduction diffusion. Single-phase nanocrystalline magnetic powders with high coercivity were prepared by regulating the experimental parameters and rare earth elements. The grain size of Nd-Fe-B powder obtained by 5 wt% TbHx addition was 68.1 nm, with a high coercivity of 18.38 kOe. After purification and dehydrogenation, the coercivity was 6.68 kOe, and the coercivity mechanism was controlled by reverse magnetic domain nucleation. The low temperature in this study significantly reduced the energy consumption for the calcium reduction regeneration of sludge. It facilitated the preparation of nanocrystalline Nd-Fe-B powders with high coercivity, offering a new idea for recycling Nd-Fe-B sludge.
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•Regenerated Nd-Fe-B powder was prepared from sludge via mechanochemical approach.•The regeneration process was realized at a relatively low temperature of 850 °C.•The prepared (Nd,Tb)2Fe14B nanocrystalline powders exhibit excellent coercivity.•The coercivity mechanism was controlled by reverse magnetic domain nucleation.
•Fe/MnO2@C composites with unique Schottky heterojunction have been designed by a simple modified arc-discharge method.•Compared to binary composite, ternary Fe/MnO2@C composite show attractive ...advantages in microwave absorption performs.•A maximum reflection loss of − 53.6 dB is observed at 2 mm thickness. And the effective bandwidth reaches 6.35 GHz.
The ubiquitous and further deterioration of electromagnetic environment has put forward higher demand for microwave absorption materials with the rapid advancement of 5 G communication and artificial intelligence. Rational manipulation of materials with unique heterojunctions and adjustable electromagnetic properties as lightweight and high-efficiency microwave absorption is the focus and difficulty of research at home and abroad. Schottky junction is designed and fabricated via implanting Fe/MnO2 nanocrystal confined in carbon matrix, wherein core nanoclusters are tailored. Manganese oxide coupling magnetic metallic iron lamellar nanocrystal benefits the improvement of static magnetization and tuning graphitization degree. The fascinating heterojunction by modifying a Schottky junction can not only enable balance among loss capacity and impedance matching, but also can accelerate the carrier migration and promote abundant interfaces. The efficient microwave absorption is optimized yielding maximum reflection loss of − 53.60 dB and broadening the effective bandwidth of 6.35 GHz. Furthermore, tailoring the morphology of implanted core nanoclusters successfully realizes selective-frequency of microwave absorption. The ternary Fe/MnO2@C composite formed by the self-assembly of Fe/MnO2 nanocrystal core and carbon shell show superior advantages compared to binary composite (e.g., Fe@C, Fe@MnO2, MnO2@C) in microwave absorption performance. Thus, the performances of appropriately tailored nanoclusters with unique architecture endow optimal synergistic effects between magnetic and dielectric loss.
Spider venom has been found to show its anticancer activity in a variety of human malignancies, including lung cancer. In this study, we investigated the anti-cancer peptide toxin LVTX-8, with linear ...amphipathic alpha-helical conformation, designed and synthesized from the
DNA library of spider
. Multiple cellular methods, such as CCK-8 assay, flow cytometry, colony formation assay, Transwell invasion and migration assay, were performed to detect peptide-induced cell growth inhibition and anti-metastasis in lung cancer cells. Our results demonstrated that LVTX-8 displayed strong cytotoxicity and anti-metastasis towards lung cancer in vitro. Furthermore, LVTX-8 could suppress the growth and metastasis of lung cancer cells (A549 and H460) in nude mouse models. Transcriptomics, integrated with multiple bioinformatics analysis, suggested that the molecular basis of the LVTX-8-mediated inhibition of cancer cell growth and metastasis manifested in two aspects: Firstly, it could restrain the activity of cancer cell division and migration through the functional pathways, including "p53 hypoxia pathway" and "integrin signaling". Secondly, it could regulate the expression level of apoptotic-related proteins, which may account for programmed apoptosis of cancer cells. Taken together, as an anticancer peptide with high efficiency and acceptable specificity, LVTX-8 may become a potential precursor of a therapeutic agent for lung cancer in the future.
In modern animal husbandry, breeders pay increasing attention to improving sow nutrition during pregnancy and lactation to favor the health of neonates. Sow milk is a main food source for piglets ...during their first three weeks of life, which is not only a rich repository of essential nutrients and a broad range of bioactive compounds, but also an indispensable source of commensal bacteria. Maternal milk microorganisms are important sources of commensal bacteria for the neonatal gut. Bacteria from maternal milk may confer a health benefit on the host.
Sow milk bacteria were isolated using culturomics followed by identification using 16S rRNA gene sequencing. To screen isolates for potential probiotic activity, the functional evaluation was conducted to assess their antagonistic activity against pathogens in vitro and evaluate their resistance against oxidative stress in damaged Drosophila induced by paraquat. In a piglet feeding trial, a total of 54 newborn suckling piglets were chosen from nine sows and randomly assigned to three treatments with different concentrations of a candidate strain. Multiple approaches were carried out to verify its antioxidant function including western blotting, enzyme activity analysis, metabolomics and 16S rRNA gene amplicon sequencing.
The 1240 isolates were screened out from the sow milk microbiota and grouped into 271 bacterial taxa based on a nonredundant set of 16S rRNA gene sequencing. Among 80 Pediococcus isolates, a new Pediococcus pentosaceus strain (SMM914) showed the best performance in inhibition ability against swine pathogens and in a Drosophila model challenged by paraquat. Pretreatment of piglets with SMM914 induced the Nrf2-Keap1 antioxidant signaling pathway and greatly affected the pathways of amino acid metabolism and lipid metabolism in plasma. In the colon, the relative abundance of Lactobacillus was significantly increased in the high dose SMM914 group compared with the control group.
P. pentosaceus SMM914 is a promising probiotic conferring antioxidant capacity by activating the Nrf2-Keap1 antioxidant signaling pathway in piglets. Our study provided useful resources for better understanding the relationships between the maternal microbiota and offspring. Video Abstract.
Gut microbes can affect host adaptation to various environment conditions. Escherichia coli is a common gut species, including pathogenic strains and nonpathogenic strains. This study was conducted ...to investigate the effects of different E. coli strains in the gut on the health of pigs. In this study, the complete genomes of two E. coli strains isolated from pigs were sequenced. The whole genomes of Y18J and the enterotoxigenic E. coli strain W25K were compared to determine their roles in pig adaptation to disease. Y18J was isolated from feces of healthy piglets and showed strong antimicrobial activity against W25K
. Gene knockout experiments and complementation analysis followed by modeling the microbe-microbe interactions demonstrated that the antagonistic mechanism of Y18J against W25K relied on the bacteriocins colicin B and colicin M. Compared to W25K, Y18J is devoid of exotoxin-coding genes and has more secondary-metabolite-biosynthetic gene clusters. W25K carries more genes involved in genome replication, in accordance with a shorter cell cycle observed during a growth experiment. The analysis of gut metagenomes in different pig breeds showed that colicins B and M were enriched in Laiwu pigs, a Chinese local breed, but were scarce in boars and Duroc pigs.
This study revealed the heterogeneity of E. coli strains from pigs, including two strains studied by both
and wet experiments in detail and 14 strains studied by bioinformatics analysis. E. coli Y18J may improve the adaptability of pigs toward disease resistance through the production of colicins B and M. Our findings could shed light on the pathogenic and harmless roles of E. coli in modern animal husbandry, leading to a better understanding of intestinal-microbe-pathogen interactions in the course of evolution.
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