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Usually the improved coercivity of rare earth (RE) based 2:14:1-type permanent magnets via RE-rich intergranular additives is achieved at the cost of more corrosion channels and deteriorated corrosion resistance, which remains a challenging hurdle in the RE-Fe-B community. Distinctly, here we report the concurrent improvements of corrosion resistance and coercivity in 40 wt.% Ce-substituted Nd-Ce-Fe-B sintered magnets through engineering the intergranular phase using simple (Nd, Pr)Hx additive. The dehydrogenated Nd/Pr changes the RE concentration gradients between 2:14:1 matrix and intergranular phases during sintering and enlarges the fraction of corrosion-resistant REFe2 phase, rather than the conventionally assumed Nd/Pr-rich intergranular phase with high chemical vulnerability. The spontaneous formation of REFe2 intergranular phase after (Nd, Pr)Hx addition generates the uniquely enhanced corrosion resistance against the hot/humid and acidic environments, and counts as one peculiar feature of Nd-Ce-Fe-B magnets at high Ce substitution level, being distinct from previously reported Ce-free/lean RE-Fe-B. Simultaneously, the formation of continuous grain boundaries enhances the coercivity from 8.7 to 12.5 kOe with trace addition of (Nd, Pr)Hx. Above findings may spur progress towards developing a high-performance Nd-Ce-Fe-B permanent magnet.

Introduction Mushroom-forming fungi comprise diverse species that develop complex multicellular structures. In cultivated species, both ecological adaptation and artificial selection have driven genome evolution. However, little is known about the connections among genotype, phenotype and adaptation in mushroom-forming fungi. Objectives This study aimed to (1) uncover the population structure and demographic history of Lentinula edodes, (2) dissect the genetic basis of adaptive evolution in L. edodes, and (3) determine if genes related to fruiting body development are involved in adaptive evolution. Methods We analyzed genomes and fruiting body-related traits (FBRTs) in 133 L. edodes strains and conducted RNA-seq analysis of fruiting body development in the YS69 strain. Combined methods of genomic scan for divergence, genome-wide association studies (GWAS), and RNA-seq were used to dissect the genetic basis of adaptive evolution. Results We detected three distinct subgroups of L. edodes via single nucleotide polymorphisms, which showed robust phenotypic and temperature response differentiation and correlation with geographical distribution. Demographic history inference suggests that the subgroups diverged 36,871 generations ago. Moreover, L. edodes cultivars in China may have originated from the vicinity of Northeast China. A total of 942 genes were found to be related to genetic divergence by genomic scan, and 719 genes were identified to be candidates underlying FBRTs by GWAS. Integrating results of genomic scan and GWAS, 80 genes were detected to be related to phenotypic differentiation. A total of 364 genes related to fruiting body development were involved in genetic divergence and phenotypic differentiation. Conclusion Adaptation to the local environment, especially temperature, triggered genetic divergence and phenotypic differentiation of L. edodes. A general model for genetic divergence and phenotypic differentiation during adaptive evolution in L. edodes, which involves in signal perception and transduction, transcriptional regulation, and fruiting body morphogenesis, was also integrated here.

Advanced electromagnetic (EM) wave absorbers with wide bandwidth is crucial to avoid EM interference and radiation, while achieving compensational attenuation at different frequencies is challenging. Herein, two-dimensional (2D) sandwiched FeNi@SnO2 have been designed, for which SnO2 nanosheets provide numerous heterogeneous nucleation sites for the growth of dispersive FeNi nanoparticles with reduced size. The SnO2 exhibits dipole polarization at 21.45 GHz with a width of ∼4.00 GHz, while the FeNi nanoparticles induce exchange resonance at 18.13 GHz (∼6.00 GHz width) and interfacial polarization at 15.97 GHz (∼6.00 GHz width). Such complementary attenuation mechanisms give rise to an impressive ultra-wide effective absorption bandwidth of 11.70 GHz with strong absorption of -49.1 dB at a small thickness of 1.75 mm. Not only superior EM wave absorption is achieved in this work, it also provides a versatile strategy to integrate different loss mechanisms in the design of EM wave absorbers with extra-wide bandwidth.

Listeria monocytogenes (L. monocytogenes) is one of the top five dangerous foodborne pathogens which widely exists in most raw food and has approximately 30 % mortality rate in high-risk groups. Food safety caused by foodborne pathogens is still a major problem faced by humans in all world. The conventional analytical methods currently used involve complex bacteriological tests and usually take several days for incubation and analysis. Thus, in order to prevent the spread of disease, the development of a detection method with high speed, high accuracy and sensitivity is urgent and necessary. Herein, we developed an approach for the identification and magnetic capture of L. monocytogenes by using core@shell Fe3O4@silica nanoparticles terminated with hydroxyl or amine groups. Our results show that both amine- and hydroxyl-terminated Fe3O4@silica core@shell nanoparticles functionalized with specific antibodies, present 95.2 %±6.2 % and 98.6 %±0.3 % capture efficacies, respectively. However, without conjugating the specific antibodies, the hydroxyl-terminated Fe3O4@silica nanoparticles exhibit 17.6 %±1.6 % efficacy, while the amine-terminated one remains 93.2 %±9.2 % capture efficiency ascribed to the high affinity. This study quantitatively uncovers the specific and non-specific recognitions relevant to the molecular-scale physiochemical interactions between the microorganisms and the functionalized particles, and the results from this work can be generalized and extended to other bacterial species by changing antibodies, also have important implications in developing advanced analytic methods.

Anisotropy engineering serves as an effective method to achieve unique properties and enhanced performance of materials. Here MOF-71 and derivatives with tuned anisotropy have been achieved via facial tuning the proticity of the solvents, giving rise to nanoflake assemblies into bellows-, boat- and flower-like microstructures. Three anisotropy dimensions including Faceting, Aspect ratio and Arrangement have been proposed to describe the anisotropy of the assemblies, which are further evaluated by heterotype ( H ¯ ), flatness ( F ¯ ) and orderliness ( O ¯ ). Combined off-axis electron holography and electromagnetic scattered field simulation visualize uniform distribution of magnetic lines due to enhanced anisotropy of the bellows-like derivatives. This gives rise to strengthened magnetic loss and electromagnetic wave absorption for the anisotropy evolution from the flower-, boat-to bellows-like structure. As such the work not only provides versatile strategy for anisotropy engineering and reification of the anisotropy for complicated assembled structures, but also insights on impacts of the anisotropy on the distribution of stray field, magnetic dipoles and scattered field for the design of electromagnetic absorbers, which are extendable to various areas including but not limited to magnetics, electrics and optics.

Amount of H2S and SO2 were generated during the SCWG of sewage sludge. It is essential to reduce the sulfur concentration in syngas for depth utilization of syngas from SCWG of sewage sludge. The syngas desulfurization ability of five additives (KOH, K2CO3, NaOH, Na2CO3, AC) were tested and the result indicated that K2CO3 had the best syngas desulfurization effect while KOH could significantly promote the yield of syngas at 450 °C and 4% loading. Increasing KOH and K2CO3 loading to 12% could reduce around 90% of sulfur in syngas comparing to no additives. The XPS analysis results indicated that alkali additives promoted the cyclization and oxidation of unstable sulfur compounds in raw sludge, which can convert it into stable sulfur compounds such as thiophene, sulfone and sulfate. The sulfur in liquid was mainly in the forms of sulfate, and the effect of alkali and AC additive on sulfur in liquid was relatively weak.

MnZn soft magnetic ferrites have been widely utilized in power electronics, owing to the combined merits of high permeability and low energy loss. However, their deployment would result in a drastic increase in power dissipation at >3 MHz, thus limiting the scope extent of miniaturization, together with their efficiency. Here, we report a high-performance MnZn ferrite by doping multiple ions (La, Ti, Si, Ca) at grain boundaries, achieving the most optimized power loss of 267 kW/m3 at 5 MHz (10 m T, 100 °C) and initial permeability of 644, which is much better than the previously reported results and commercial products. Such an improvement is attributed to weakened magnetic exchange coupling at grain-boundary regions, associated with a significant transition from the multi- to mono-domain structures, originating physically from large crystallographic mis-orientations (>25°). The present study bears important significance in understanding the intrinsic correlation between the crystallographic mis-orientation and magnetic domain structure, and provides an alternative way for optimizing high-frequency soft magnetic ferrites.