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Perovskite CsPbX3 (X = Cl, Br, I) nanocrystals with advantages of high quantum yield, narrow emission peaks, and tunable fluorescence are considered as the next generation of light‐emitting sources. However, fluorescence degradation due to the poor stability of perovskite nanocrystals in moisture, high temperature, and illumination remains one of the greatest challenges in their further development. In this work, a fully dense coating strategy is proposed to improve the overall stability of perovskite nanocrystals, especially under high‐density laser irradiation. A mesoporous silica SiO2 layer is introduced to construct a stable coating for isolating the perovskite from external environment. To eliminate the pores of the CsPbX3@SiO2, an inorganic glass is also employed via solution‐combustion technique to generate a fully compact encapsulation for further stability promotion. The as‐prepared nanocrystal‐in‐glass composite exhibits efficient and stable fluorescence performance in luminous efficiency, chromaticity, and long‐term reliability in the conditions of thermal shock, humidity, and blue laser irradiation. With the integration of red/green/blue emitting nanocrystals, the color gamut of the white laser lighting source covers 134% of the National Television Standards Committee standard, providing exciting opportunity for high performance laser‐driven white light generation. [ABSTRACT FROM AUTHOR]

Broadband near‐infrared (NIR) phosphors have recently received considerable attention in spectroscopy technology fields, but designing inexpensive, emission peaks centered above 800 nm, and multimodal broadband NIR luminescence material still remains a great challenge. Here, by selecting stannate compound Mg2SnO4 (MSO) as the host, a kind of broadband NIR phosphor MSO:Cr3+ with multimode luminescence properties is reported. The designed material exhibits an emission peaking at 800 nm and a full‐width at half maximum of 180 nm (≈2730 cm−1). The site occupation of Cr3+ in MSO is unraveled by density functional theory calculation. The constructed NIR light‐emitting device based on MSO:Cr3+ displays a high NIR output power of 187.19 mW@100 mA and remarkable photoelectric efficiency of 13.67%, and its multifunctional applications in information encryption, non‐destructive detection, and so on are also demonstrated. Additionally, through defect site reconstruction, MSO:Cr3+ presents superior broadband NIR persistent luminescence (PersL) properties with PersL duration time longer than 50 h. This work provides a feasible strategy to develop intelligent optical material integrated with multimodal luminescence through low‐cost stannate compounds as the host toward versatile applications such as non‐destructive detection and bioimaging. [ABSTRACT FROM AUTHOR]

The design of high-performance and low-cost oxygen evolution reaction (OER) electrocatalysts is crucial for environment friendly hydrogen production. Some transition metals have been proven to be good substitutes for noble metals due to their unique electronic structural characteristics and good electrocatalytic performances, with examples including nickel and cobalt, which are usually used to prepare OER electrocatalysts. In this work, we synthesized three-dimensional Ni-Co-Fe ternary layered double hydroxide nanosheet array electrocatalysts via hydrothermal process. Iron element was introduced into the Ni-Co based hydroxide. The ternary layered double hydroxide has a nanoarrays microstructure. Theoretical analysis confirms that by adjusting the ratio of Ni/Co/Fe, the microstructure of the catalyst changes significantly. Attributed to the special nanostructure, the catalysts show superior catalytic activities in oxygen evolution reaction (OER). The results show that a small overpotential of 222 mV at the current density of 20 mA·cm−2 for the OER in 1.0 M KOH is acquired. A small Tafel slope of 61.22 mVdec−1 and a maximum specific capacitance of 239 Fg−1 are also obtained. [ABSTRACT FROM AUTHOR]

Chemical looping with O2 uncoupling aims at using an oxygen carrier (OC) with O2 uncoupling behaviour to promote fuel conversion. Natural ilmenite ores have been considered highly promising OCs for chemical looping technology; however, they do not possess any O2 uncoupling behaviour. Mn‐modified ilmenite ores as OCs are capable of O2 uncoupling, while most of them are synthesized via complicated procedures by using costly chemicals. In this study, a strategy of calcination treatment on ilmenite ores mixed with manganese ores has been established to introduce Mn into the ilmenite OCs, endowing them with O2 uncoupling behaviour in a simple and low‐cost manner. The O2 uncoupling behaviour from Mn‐modified ilmenite ores is mainly due to the newly formed (Fe1−xMnx)2O3/(Fe1−xMnx)3O4 crystal phases generated during the calcination treatment, which also alleviate the thermodynamic limit of the Mn2O3‐Mn3O4 redox pair. As a result, the Mn‐modified ilmenite ore OCs can release O2 at high temperatures when decreasing the oxygen partial pressure. But more importantly, the reduced OCs can be restored in the air isothermally. This established simple calcination treatment method can be used as a low‐cost strategy for producing ilmenite‐based OCs with O2 uncoupling behaviour. The O2 uncoupling behaviour is expected to be beneficial to chemical looping combustion of fuels, promote fuel conversion, minimize OC loading, and reduce energy consumption. [ABSTRACT FROM AUTHOR]

Background and Purpose: Although increasing evidence illustrated that the bidirectional communication between the brain and the gut is closely related to the occurrence of various complex diseases. Limited effort has been made to explore the influence of intestinal flora on the risk of ischaemic stroke. The present study aims to identify microbiota and specialized microbiota metabolites related to the occurrence and treatment of ischaemic stroke. Experimental Approach: The role of microbiota in the occurrence and the treatment of ischaemic stroke was evaluated on ischaemia/reperfusion (I/R), pseudo‐germ‐free and faecal transplantation animals. The target microbiota and specialized metabolites were identified by comparing their distribution in flora and metabolomic profiles in ischaemic stroke patients and animals with compared with healthy controls. The effects and mechanisms involved of the targeted metabolites in ischaemic stroke were explored in ischaemia/reperfusion rats, hypoxia/reoxygenation PC12 cells and LPS‐induced inflammatory BV2 cells. Key Results: Both ischaemic stroke patients and I/R rats had significant accumulation of branched‐chain amino acids, which were closely associated with gut microflora dysbiosis and the development of ischaemic stroke. Lactobacillus helveticus (L.hel) and Lactobacillus brevis (L.bre) are identified as the microbiota most affected by ischaemia/reperfusion modelling and treatment. L.hel and L.bre colonization exhibited significant neuroprotective activity and could greatly alleviate the accumulation of branched‐chain amino acids. In addition, branched‐chain amino acid (BCAA) accumulation was shown to exacerbate microglia‐induced neuroinflammation by activating AKT/STAT3/NF‐κB signalling. Conclusion and Implications: Our findings demonstrated the crucial role of intestinal flora and microbiota metabolites in the occurrence and treatment of ischaemic stroke. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L., as an invasive plant, has negatively impacted the ecosystem functioning and stability of the terrestrial ecosystem in China. However, little information was available for its effects on microorganisms in the Yellow River Delta (YRD), the biggest newly-formed wetland in China. In the present study, high-throughput sequencing technology was used to obtain the bacterial community in soils and roots of different plant species, including P. hysterophorus and some native ones in the YRD. Our results showed that the Proteobacteria, Acidobacteriota, Gemmatimonadota, and Actinobacteriota were dominant in the rhizosphere soils of P. hysterophorus (84.2%) and Setaria viridis (86.47%), and the bulk soils (80.7%). The Proteobacteria and Actinobacteriota were dominant within the root of P. hysterophorus. A total of 2468 bacterial OTUs were obtained from different groups among which 140 were observed in all the groups; 1019 OTUs were shared by P. hysterophorus non-rhizosphere soil bacteria (YNR) P. hysterophorus rhizosphere soil bacteria (YRR) groups. The indexes of the ACE (823.1), Chao1 (823.19), Simpson (0.9971), and Shannon (9.068) were the highest in the YRR groups, showing the greatest bacterial community diversity. Random forest analysis showed that the Methylomirabilota and Dadabacteria (at the phylum level) and the Sphingomonas, and Woeseia (at the genus level) were identified as the main predictors among different groups. The LEfSe results also showed the essential role of the Acidobacteriota in the YRR group. The SourceTracker analysis of the bacterial community of the YRR group was mainly from GBS groups (average 53.14%) and a small part was from YNR groups (average 6.56%), indicating that the P. hysterophorus invasion had a more significant effect on native plants' rhizosphere microorganisms than soil microorganisms. Our observations could provide valuable information for understanding the bacterial diversity and structure of the soil to the invasion of P. hysterophorus. [ABSTRACT FROM AUTHOR]

Flexible sensors for high strain sensitivity and dynamic stability are important for the development of human-interactive and health-monitoring devices. However, establishing a stable conductive network with low-conductivity material filling that can resist tensile strain failure and achieve high device performance still faces significant challenges. Herein, a highly stretchable and sensitive strain sensor with strong dynamic stability and low conductive materials filling was fabricated based on highly conductive multi-walled carbon nanotubes (MWCNTs) and Fe nanowires (NWs) to construct a porous-designed bi-conducting network using a salt sacrificial template approach. The porous-designed Fe NW/MWCNT strain sensor (PFMS) with low material filling (3.6 wt.% Fe NWs and 10.6 wt.% MWCNTs) showed high sensitivity with a gauge factor (GF) of 134.98 (strain range 0–22%) and 569.37 (strain range 22%–60%), which is much higher compared with the pure MWCNT strain sensor with a GF of 7.46. This is attributed to the significant change in the contact area and contact resistance of the Fe NW/MWCNT bi-conducting network during tensile strain. In addition, the PFMS exhibited high repetitive stability over 2000 stretching-releasing cycles. When attached to the human body, the PFMS functions as a health-monitoring device, that can accurately distinguish human motions such as the bending of fingers, knees, and elbows. Finally, the proposed strategy pens a novel avenue for constructing porous conductive networks using polymer composites and is highly competitive for developing high-performance strain sensors. [ABSTRACT FROM AUTHOR]

With the growth of building monitoring network, increasing human resource and funds have been invested into building monitoring system. Computer vision technology has been widely used in image recognition recently, and this technology has also been gradually applied to action recognition. There are still many disadvantages of traditional monitoring system. In this paper, a human activity recognition system which based on the convolution neural network is proposed. Using the 3D convolution neural network and the transfer learning technology, the human activity recognition engine is constructed. The Spring MVC framework is used to build the server end, and the system page is designed in HBuilder. The system not only enhances efficiency and functionality of building monitoring system, but also improves the level of building safety.