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Tunable behavior in electrocatalysis by external multifields, such as magnetic field, thermal field, and electric field, is the most promising strategy to expand the theory, design, and synthesis of state‐of‐the‐art catalysts and the cell in the near future. Here, a systematic investigation for the effect of external magnetic field and thermal field on methanol oxidation reactions (MOR) in magnetic nanoparticles is reported. For Co42Pt58 truncated octahedral nanoparticles (TONPs), the catalytic performance in MOR is greatly increased to the maximum of 14.1% by applying a magnetic field up to 3000 Oe, and it shows a monotonical increase with increasing working temperature. The magnetic enhanced effect is closely related to the Co content of CoxPt100‐x TONPs. Furthermore, the enhancement effect under a magnetic field is more obvious for Co42Pt58 TONPs annealed at 650 °C. First‐principle calculation points out that the magnetic fields can facilitate the dehydrogenation of both methanol and water by suppression of entropy of the electron spin and lowering of the activation barrier, where OHad intermediates on Co sites play a more important role. The application of magnetic fields together with thermal fields in MOR provides a new prospect to manipulate the performance of direct methanol fuel cells, which will accelerate their potential applications. [ABSTRACT FROM AUTHOR]

Anomaly detection is a crucial task for hyperspectral image processing. Most popular methods detect anomalies at the pixel level, while a few algorithms for anomaly detection only utilize subpixel level unmixing technology to extract features without fundamentally analyzing the anomalies. To better detect and separate the anomalies from the background, this paper proposes a dual-view hyperspectral anomaly detection method by taking account of the anomaly analysis at both levels mentioned. At the pixel level, the spectral angular distance is adopted to calculate the similarities between the central pixel and its neighbors in order to further mine the spatial consistency for anomaly detection. On the other hand, from the aspect of the subpixel level analysis, it is considered that the difference between the anomaly and the background usually arises from dissimilar endmembers, where the unmixing will be fully implemented. Finally, the detection results of both views are fused to obtain the anomalies. Overall, the proposed algorithm not only interprets and analyzes the anomalies from dual levels, but also fully employs the unmixing for anomaly detection. Additionally, the performance of multiple data sets also confirmed the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Two-dimensional van der Waals (2D vdW) magnets have attracted great attention recently and possess the unprecedented advantages of incorporating high-quality vdW heterostructures and homostructures into spintronic devices, and exploring various physical phenomena or technologies. Among them, Fe5GeTe2 (F5GT) has ferromagnetic order close to room temperature, however the magnetic properties near its intrinsic transitions and F5GT-based 2D devices remain mostly unexplored. Here, we systematically demonstrate the peculiar magnetic properties of Fe5GeTe2 nanoflakes near its intrinsic transition temperature (Tp) which is far lower than its Curie temperature (TC) of ∼ 265 K, and firstly discover anomalous magnetoresistance effect in F5GT homo-junctions by magneto-transport measurements. The strongest anomalous Hall effect occurs around Tp which is located in a temperature range from 130 to 160 K for the F5GT nanoflakes with different thicknesses. Furthermore, negative magnetoresistance (N-MR) and butterfly-shaped magnetoresistance (B-MR) are observed in F5GT homo-junction devices, and they appeared only in an intermediate temperature range from 110 to 160 K, noticeably showing the maxima near the Tp rather than the lowest temperature. Our experimental results clearly reveal the significant influence of intrinsic transitions on magnetic properties of F5GT and magnetoresistance effect in F5GT homo-junction devices, which imply a new strategy to achieve high-performance 2D spintronic devices by tuning intrinsic magnetic or structural transitions in 2D vdW magnets. [ABSTRACT FROM AUTHOR]

Isocyanate modified liquid was prepared by isocyanate and diluted asphalt. Then, isocyanate modified asphalt cold patch asphalt mixture was prepared by combining isocyanate modified liquid with aggregates. Crosslinking reaction was used to improve the performance of cold patch asphalt mixture. The experimental results show that the modified liquid exhibits good short-term storage stability. By adjusting the dosage of PM-200 and PPU-1102 isocyanate, the viscosity and the reactivity of the system can be effectively regulated, from which the mechanical properties and water damage resistance of the cold patch asphalt mixture can be well adjusted. When the proportion of diluted asphalt, PM-200 and PPU-1102 in the modified liquid are 50%, 10% and 40%, respectively, the Marshall stability and the residual stability of the cold patch asphalt mixture with 6% liquid content reaches 24.8kN and 86.1%, respectively, which are close to those of the hot asphalt mixture. Field experiments show that compared with traditional material, the isocyanate modified cold patch asphalt mixture exhibits higher durability. [ABSTRACT FROM AUTHOR]