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Sm3+, Mn4+ co‐activated LaGaO3 phosphors, giving the characteristic emissions of orange and red emission simultaneously, were prepared by a solid‐state reaction. Their luminescence properties, energy transfer behavior, thermal stability, and ratiometric temperature sensing performance were investigated. Thanks to the inhibition of energy transfer between Sm3+ and Mn4+ ions at high temperature and the reconstruction of the traps, the distinct optical behavior of the involved activators dependent on the ambient temperature was evaluated. Anti‐thermal quenching performance of Sm3+ ions along with the emission declination of Mn4+ ions was observed. Hence, the optical thermometry characteristics of the resultant phosphor based on the fluorescent intensity ratio (orange/red) realize a recorded temperature sensitivity of 4.19% K−1 and 2.09% K−1. Moreover, the as‐explored film combined with the LaGaO3: Sm3+, Mn4+ phosphor is demonstrated to be a promising multi‐color optical thermometer. [ABSTRACT FROM AUTHOR]

Counter-current chromatography (CCC) target-guided by on-line HPLC with post-column DPPH assay was established for efficient screening and isolation of large amount of antioxidants from Eupatorium lindleyanum DC. On-line HPLC with post-column DPPH reaction was used to screen the antioxidants and optimize the biphasic solvent system of CCC, then the targeted peaks were purified using CCC. In the present study, three compounds, nepetin, cirsiliol and jaceosidin, were targeted and successively separated from n-butanol fraction of E. lindleyanum DC. by this strategy. All three compounds showed strong DPPH radical scavenging activity. These results confirmed that the strategy would be an efficient and effective method to isolate antioxidants from complex mixtures. [ABSTRACT FROM AUTHOR]

Through a brief survey of the typical definitions of hybrid warfare (HW), this article illustrates the five salient features of HW: synergy, ambiguity, asymmetry, innovative disruption and battle over psychology; then based on a HW model proposed by Erik Reichborn-Kjennerud and Patrick Cullen, the article discusses the impact of Artificial Intelligence on the five instruments of power – military, political, economic, civil and informational (MPECI), and analyses the changes and continuities of HW in the age of Artificial Intelligence. [ABSTRACT FROM AUTHOR]

Conducting polymer‐metal Schottky diodes show an interesting mechanical energy‐to‐electricity conversion ability to generate direct current (DC) power without rectification. However, little is reported about how dopants in conducting polymer affect the energy conversion behavior of Schottky diodes. In this study, a novel effect of dopants on mechanical energy‐to‐DC electricity conversion of conducting polymer‐metal Schottky devices is demonstrated. Using polyaniline (PANI) as a model, conducting polymers doped with a series of protonic acids is prepared. Without dopant, the device exhibits low mechanical‐to‐electrical outputs. Protonic acid doping enhances device energy conversion ability, and the dopant molecular dimension plays a significant part in deciding device performance. When HCl is used as dopant, the PANI device could produce peak outputs of 0.9 V and 33.9 µA cm−2 under compressive impact. These novel understandings foster the design of DC generators for various applications. Dopant in conducting polymer shows significant effect on the power outputs of Schottky DC generators. The device with chlorine ion dopant has almost four orders of magnitude increase in electrical output compared to that without dopant in conducting polymer. [ABSTRACT FROM AUTHOR]

The rational construction of highly active and durable oxygen-reactive electrocatalysts for oxygen reduction/evolution reaction (ORR/OER) plays a critical role in rechargeable metal-air batteries. It is pivotal to achieve optimal utilization of electrocatalytically active sites and valid control of the high specific internal surface area. Inspiration for designing electrocatalysts can come from nature, as it is full of precisely manipulated and highly efficient structures. Herein, inspired by earthworms fertilizing soil, a 3D carbon nanofibrous electrocatalyst with multiple interconnected nanoconfined channels, cobalt-based heterojunction active particles and enriched N, S heteroatoms (Co/Co 3 O 4 /CoF 2 @NSC with confined channels) is rationally designed, showing superior bifunctional electrocatalytic activity in alkaline electrolyte, even outperforming that of benchmark Pt/C-RuO 2 catalyst. This work demonstrates a new method for porous structural regulation, in which the internal confined channels within the nanofibers are controllably formed by the spontaneous migration of cobalt-based nanoparticles under a CO 2 atmosphere. Theoretical analysis reveals that constructing Co/Co 3 O 4 /CoF 2 @NSC electrocatalyst with confined channels can greatly adjust the electron distribution, effectively lower the reaction barrier of inter-mediate and reduce the OER/ORR overpotential. This work introduces a novel and nature-inspired strategy for designing efficient bifunctional electrocatalysts with well-designed architectures., (© 2024 Wiley‐VCH GmbH.)

The airborne particulate matter (PM) seriously threatens people's health. Personal protective equipment with electrospun nanofibers is an effective method to make people away from air pollutants. Herein, 3D waterproof melamine-formaldehyde polyvinyl alcohol (MF-PVA) nanofibrous membranes are fabricated by a one-step method combining multi-unit needleless electrospinning and a thermal treatment device in a line. 3D nanofibrous structures can be controlled by adjusting the solution concentration of each unit. The PVA nanofibrous membranes become waterproof after cross-linking with MF resin in the following thermal treatment device. The optimized MF-PVA nanofibrous membrane shows excellent air filtration performance (97.3% for PM 0.3 , 100% for PM 1.0 , and 100% for PM 2.5 ) and low air resistance (76 Pa). These 3D waterproof MF-PVA nanofibrous membranes exhibit ultra-stable performance in various practical environments., (© 2022 Wiley-VCH GmbH.)