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[Display omitted] • A phosphorus/nitrogen-containing hyperbranched epoxy resin (HPITT) was simply synthesized. • Both flame retardancy and toughness of epoxy thermosets were enhanced by HPITT. • EP/HPITT thermosets maintained excellent T g and T 5%. • HPITT was a prospective and versatile modifier for epoxy thermosets. Concurrently enhancing the flame retardancy and toughness without sacrificing strength, thermal decomposition temperature, and glass transition temperature (T g) of epoxy thermosets is still challenging. Herein, a new phosphorus/nitrogen-containing hyperbranched epoxy resin (HPITT) was synthesized from itaconic anhydride, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, piperazine, and triglycidyl isocyanurate by a facile method. The HPITT was then utilized for synergistic flame retarding and toughening modification of epoxy thermosets. Upon the introduction of 10 wt% HPITT, the epoxy thermosets reached a limiting oxygen index (LOI) of 31.5 % and UL-94 V-0 rating. Meanwhile, the peak heat release rate (PHRR) and total smoke production (TSP) decreased by 32.3 % and 27.7 % when compared to neat epoxy thermosets, respectively. Moreover, the synergistic flame retarding functions of phosphaphenanthrene, piperazine and isocyanurate segments in HPITT were demonstrated by combined gas and char phase residue analyses. Compared to neat epoxy, features such as the impact strength, tension strength, and flexural strength of the modified epoxy thermosets increased by respectively 53.9 %, 29.2 %, and 58 % owing to intramolecular cavities, rigid segments, and high crosslinking density supplied by HPITT. Moreover, the modified epoxy thermosets still maintained excellent T g and thermal decomposition temperature. In sum, an attractive strategy for concurrently enhancing flame retardancy and toughness of epoxy thermosets was proposed, useful for future advanced applications in adhesives, coatings, and composite materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel fluorogenic RNA aptamer output sensor via in vitro transcription (IVT) activated by RPA (ROSAR) was developed. • The proposed ROSAR for pathogens nucleic acid (DNA or RNA) testing displayed outstanding performance. • A paper-based ROSAR was developed for improving the stability of reagents and facilitate POC testing. • An integrated, low-cost, and user-friendly device was designed for paper-based ROSAR readout using mobile phone. • The proposed ROSAR and paper-based ROSAR were validated using clinical samples, showed the potential of clinical application. Sensitive, simple, and rapid nucleic acid testing used for pathogen detection are crucial for preventing outbreaks and transmission of infectious diseases. In this study, we present a fluorogenic RNA aptamer Output Sensors via transcription Activated by Recombinase polymerase amplification (RPA), termed ROSAR, for highly sensitive detection of DNA and RNA from pathogenic bacteria or viruses in clinical samples. The promoter primer and reporter primer facilitate the integration of the transcriptional promoter with the fluorogenic RNA aptamer transcription templates through the RPA of target DNA. Subsequently, the amplification products are transcribed by T7 RNA polymerase, producing RNA aptamer that binds to a fluorogenic dye. The assay, which can be completed within 50 min and can allow a limit of detection of level aM nucleic acid concentration, owning to the dual amplification effects of RPA and in vitro transcription. Furthermore, we develop a paper-based ROSAR by freeze-drying the reaction components, which is compatible with visual detection based on mobile phone fluorescent reader and suitable for point-of-care (POC) applications. The assay can detect various viral and bacterial nucleic acids, making it a highly promising tool for large-scale epidemic screening and rapid POC testing in home healthcare settings. [ABSTRACT FROM AUTHOR]

• Stretchable triboelectric sensor array was proposed based on the coaxial printing. • Surface microstructures and output performance of TSA were studied. • TSA is a promising candidate for electronic skin and tactile detection. With the rapid development of flexible and wearable electronics, tactile sensor array has shown great potential to detect diverse external stimuli in human–machine interactions and robotic intelligence. In this study, we developed triboelectric sensor array (TSA) with cross-laminated electrode via low-cost coaxial printing technique with the advantages of high precision, high efficiency and excellent uniformity. The results show that the proposed cross-laminated electrode based TSA possesses the characteristics of easy-fabrication process, high-sensitivity, long-term mechanical endurance and real-time trajectory sensing capacity. It can generate the maximum output voltage of 15.98 V at a frequency 4 Hz and vertical force 5 N in single electrode mode, and the maximum power is about 3.9 μW. Besides, TSA shows excellent stability under harsh mechanical bending, twisting and stretching deformation and even waterproof capability. This work offers a previously unexplored strategy for shortening individual design and fabrication cycle of flexible electronics, and promoting the potential application for stretchable sensor array in electronic skin, tactile detection and human–machine interactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Utilizing IRS effect to boost the PL energy outcoupling of perovskite phosphors. • A NMHS-LI reaction was developed to construct NP-PP structure inside the phosphors. • The NP-PP structure transformed the PL propagation from absorption mode to IRS mode. • Our NP-PP phosphor achieved an ultrahigh white luminous efficacy of 131.32 lm/W. Although stable perovskite phosphors, i.e., CsPbBr 3 /Cs 4 PbBr 6 , were extensively reported and made great progress, achieving strong photoluminescence (PL) energy outcoupling remains challenging owing to their short Stoke's shift with serious PL energy absorption. This study utilized internal resonant scattering (IRS) to improve the PL energy outcoupling (PEO) of CsPbBr 3 /Cs 4 PbBr 6 perovskite phosphor, which was realized by the nanopore-packing perovskite particles (NP-PPs) structure inside a phosphor. The nano-porous matrix hybrid solid–liquid interfacial reaction was developed to construct NP-PPs in a phosphor, and it is optimized to achieve a denser NP-PP structure with an enhanced PEO effect (2.8-fold enhanced PL intensity). Numerical results revealed that the NP-PP structure transforms the PL energy absorption mode to the IRS mode, most of the scattering PL energy evades NP-PPs instead of propagating inside. The optimized phosphor was applied to white devices, and we finally achieved an ultrahigh luminous efficacy of 131.32 lm/W based on green perovskite phosphors. This study provides a general guide for efficient perovskite phosphors utilizing the nano-porous matrix to enable the IRS effect. [ABSTRACT FROM AUTHOR]

• A planthopper gear-shaped flow channel for PEMFCs is developed. • The oxygen transport mechanism inside the GFCH-based PEMFC is revealed. • The effects of GFCHs for mitigating the oxygen starvation and boosting the reactant homogeneity in PEMFC are analyzed. • A PEMFC with an optimal GFCH with remarkable electrochemical performance is provided. The flow channel design of a proton exchange membrane fuel cell (PEMFC) is a key factor affecting the power output. This work proposes a planthopper gear-shaped flow channel (GFCH) to address the issues of oxygen starvation and reactant homogeneity in a PEMFC by strengthening oxygen transport from the flow channel to the electrode surface. Full-scale three-dimensional PEMFC based on the GFCHs is constructed to investigate and analyze the multi-phase mass transport process, flow velocity, pressure distribution and electrochemical performances, compared with the conventional serpentine flow channels (SFCHs). Results show that the GFCH remarkably boosts the oxygen transport to the electrode surface under the effects of bio-inspired strengthened structures. Due to the promoted mass transfer efficiency and reactant distribution homogeneity of the GFCHs, the peak power density of the optimized flow channel (1.04 W cm−2) is ∼ 46% higher than that of the conventional SFCH (0.71 W cm−2). The optimal structural parameters for the GFCH with 0.4 mm for the rib width and a combination of 0.6/0.4 mm for the channel height are obtained by simulation and experimental demonstration. We believe that using this novel channel shape provides a good solution for flow channel design of PEMFCs. [ABSTRACT FROM AUTHOR]