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Finding promising materials that show large thermoelectricity at low temperatures is crucial for low-temperature refrigeration applications. Here, we report a significantly large thermoelectric power factor (PF) up to 50 μW cm−1 K−2 at an extremely low temperature of ∼8 K in a quasi-one-dimensional (Q1D) antiferromagnet KMn6Bi5, in which highly electrical conductivity and dramatic enhancement of Seebeck coefficient may favor its occurrence. In addition, a giant Nernst signal has also been detected with a maximum value of 24 μV K−1 T−1 at ∼5 K. All these intriguing characteristics observed in KMn6Bi5 can be attributed to the manifestation of the unusually strong coupling among spin, charge, lattice, and one dimensionality in KMn6Bi5. Our findings provide fundamental insight into the thermal transport in Q1D antiferromagnets and should stimulate further experimental exploration of thermal transport in such Q1D family for possible thermoelectric applications at extremely low temperatures. [ABSTRACT FROM AUTHOR]

We have carried out point-contact spectroscopy (PCS) measurements on one family of antiferromagnetic Kondo semiconductor CeT2Al10 (T = Ru and Os) with a Nčel temperature TN ∼ 27.5 and 28.5 K, respectively. Their PCS conductance curves both exhibit a characteristic coherent double-peak-structure at temperatures below TN, signaling an AFM gap around the Fermi surface. The temperature dependent AFM gap Δ1 follows a Bardeen–Cooper–Schrieffer (BCS)-like mean-field behavior with a moderate gap anisotropy for PCS along different crystal axes. Another asymmetric gap-like feature is observed for both compounds at temperatures far below TN, which is consistent with opening of a new hybridization gap Δh inside the long-range ordered AFM state. Our results suggest a common itinerant nature of the anomalous AFM ordering, constraining theoretical models to explain the AFM origin in CeRu2Al10 and CeOs2Al10. [ABSTRACT FROM AUTHOR]

The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000 °C and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K. We found that Dy2Pt2O7 does not form long-range magnetic order, but displays characteristics of canonical spin ice such as Dy2Ti2O7, including (1) a large effective moment 9.64 μB close to the theoretical value and a small positive Curie–Weiss temperature θCW = +0.77 K signaling a dominant ferromagnetic interaction among the Ising spins; (2) a saturation moment ∼4.5 μB being half of the total moment due to the local 〈111〉 Ising anisotropy; (3) thermally activated spin relaxation behaviors in the low (∼1 K) and high (∼20 K) temperature regions with different energy barriers and characteristic relaxation time; and most importantly, (4) the presence of a residual entropy close to Pauling' estimation for water ice. [ABSTRACT FROM AUTHOR]

Both Halliday's Systemic Functional Linguistics (SFL) and van Dijk's theory place emphasis on context, an essential component of the two theories. In this paper, the context models in the two theories are compared and analyzed to reveal their similarities and differences. As a tool for discourse analysis, the SFL model favors ontology, attaches more importance to the systematicness of language itself and takes context as an important factor within the language system. On the other hand, van Dijk's context model highlights the cognitive attribute of language and context, particularly the effect of cognitive psychology on the communication process and outcome. [ABSTRACT FROM AUTHOR]

Finding promising materials that show large thermoelectricity at low temperatures is crucial for low-temperature refrigeration applications. Here, we report a significantly large thermoelectric power factor (PF) up to 50 μW cm−1 K−2 at an extremely low temperature of ∼8 K in a quasi-one-dimensional (Q1D) antiferromagnet KMn6Bi5, in which highly electrical conductivity and dramatic enhancement of Seebeck coefficient may favor its occurrence. In addition, a giant Nernst signal has also been detected with a maximum value of 24 μV K−1 T−1 at ∼5 K. All these intriguing characteristics observed in KMn6Bi5 can be attributed to the manifestation of the unusually strong coupling among spin, charge, lattice, and one dimensionality in KMn6Bi5. Our findings provide fundamental insight into the thermal transport in Q1D antiferromagnets and should stimulate further experimental exploration of thermal transport in such Q1D family for possible thermoelectric applications at extremely low temperatures. [ABSTRACT FROM AUTHOR]

To explore the effects of long-term tillage on bacterial community structure in different soil layers of dryland wheat fields and its relationship with soil physicochemical properties, a long-term field experiment was conducted from 2016 to 2021 in Wenxi Experimental Demonstration Base of Shanxi Agricultural University, Shanxi Province. We studied the effects of no-tillage (NT), subsoiling-tillage (ST), and deep plowing (DP) on soil physicochemical properties; α and β diversity of the bacterial community; and dominant and different species of phyla and genera in different soil layers. Additionally, PICRUSt2 was used to predict the metabolic function of soil bacterial community. The results revealed that subsoiling-tillage and deep plowing significantly increased the soil water content in the 20-40 cm soil layer and significantly decreased the soil organic carbon content in the 0-20 cm soil layer compared with that under no-tillage for five consecutive years. Compared with that under deep plowing, subsoiling-tillage significantly increased soil water content, soil organic carbon content, dissolved organic carbon content, and dissolved organic nitrogen content in the 0-20 cm soil layer. Compared with that under no-tillage, subsoiling-tillage and deep plowing increased the α diversity of the soil bacterial community in the 0-40 cm soil layer, and subsoiling-tillage was higher than deep plowing. Compared with that under no-tillage, subsoiling-tillage and deep plowing significantly increased the relative abundances of Acidobacteria and Nitrospirae in the 0-20 cm soil layer and Acidobacteria, Chloroflexi, Gemmatimonadetes, Rokubacteria, GAL15, and Nitrospirae in the 20-40 cm soil layer. Compared with that under no-tillage, subsoiling-tillage and deep plowing significantly increased the relative abundance of Nitrospira in the 0-20 cm soil layer and Rubrobacter and Streptomyces in the 20-40 cm soil layer. Compared with that under deep plowing, subsoiling-tillage significantly increased the relative abundance of Acidobacteria and Gemmatimonadetes in the 0-40 cm soil layer. Redundancy analysis demonstrated that the contents of soil organic carbon, dissolved organic carbon, and dissolved organic nitrogen in the 0-20 cm soil layer exerted positive effects on Actinobacteria and Blastococcus , and the soil water content in the 0-40 cm soil layer exerted positive effects on Acidobacteria, Chloroflexi, and Gemmatimonadetes under subsoiling-tillage. The results of PICRUSt2 prediction showed that subsoiling-tillage and deep plowing significantly increased the relative abundance of amino acid metabolism and the metabolism of cofactors and vitamins but decreased the relative abundance of lipid metabolism of bacterial communities in the 20-40 cm soil layer compared with that under no-tillage. Compared with that under deep plowing, subsoiling-tillage significantly increased the relative abundances of amino acid metabolism in the 0-40 cm soil layer and other amino acid metabolism in the 0-20 cm soil layer. In conclusion, subsoiling-tillage or deep plowing could increase the soil water content, α diversity of the soil bacterial community, and their metabolic capacity in the dryland wheat fields during the summer fallow period. The relative abundance of Acidobacteria and Gemmatimonadetes and the ability of amino acid metabolism of the bacterial community were increased by subsoiling-tillage, and thus the contents of soil dissolved organic carbon and dissolved nitrogen can be increased.