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By using density functional theory calculations combined with the nonequilibrium Green's function method and machine learning, we systematically studied the thermoelectric properties of four kinds of porous graphene nanosheets (PGNS) before and after nitrogen doping. The results show that the thermoelectric performance of porous graphene nanosheets along the armchair or zigzag chiral direction is improved due to the dramatically enhanced power factor caused by nitrogen doping. The calculated ZT values of nitrogen-doped porous graphene nanosheets are boosted by about one order of magnitude compared with those of undoped porous graphene nanosheets at room temperature. More importantly, an anisotropic thermoelectric transport is found in the nitrogen-doped porous graphene nanosheets. The results show that the ZT values of nitrogen-doped porous graphene nanosheets along the zigzag transport direction are nearly 11 times larger than those of them along the armchair transport direction. These results reveal that the thermoelectric properties of porous graphene nanosheets can be well regulated by nitrogen doping, and provide a good theoretical guidance for their application in thermoelectric devices. [ABSTRACT FROM AUTHOR]

Semiconductor nanocrystals (NCs) hold immense potential as luminescent materials for various optoelectronic applications. While significant progress has been made in developing NCs with outstanding optical properties in the visible range, their counterparts emitting in the ultraviolet (UV) spectrum are less developed. Rb2AgI3 is a promising UV-emitting material due to its large band gap and high stability. However, the optical properties of low-dimensional Rb2AgI3 NCs are yet to be thoroughly explored. Here, we synthesized Rb2AgI3 NCs via a hot injection method and investigated their properties. Remarkably, these NCs exhibit UV luminescence at 302 nm owing to self-trapped excitons. The wide-bandgap nature of Rb2AgI3 NCs, combined with their intrinsic UV luminescence, offers considerable potential for applications in UV photonic nanodevices. Our findings contribute to the understanding of Rb2AgI3 NCs and pave the way for exploiting their unique properties in advanced optoelectronic systems. [ABSTRACT FROM AUTHOR]

Simplified methods for assessing soil liquefaction potential based on the standard penetration test (SPT) are prevalent in practice and widely accepted by several seismic design codes. When encountering sites that have not been investigated using SPT, such as offshore sites or sites with a high level of gravel content, engineers can only substitute the methods based on piezocone penetration test data (CPT-qc methods) or shear wave velocity measurements (VS-based methods); however, these two approaches perform inconsistently with methods based on SPT data (SPT-N methods). As a result, this paper exploits the datasets consisting of SPT, CPTU, and in situ seismic test measurements from 13 alluvium sites in the Taipei Basin to compare the performance of prevalent SPT-N, CPT-qc, and VS-based methods. The discrepancies (uncertainties) of these methods are characterized as Gaussian distribution models, which is believed to be a feasible strategy for predicting equivalent results for SPT-N methods when SPT data are not available. Finally, the application of the proposed models to liquefaction potential index evaluation is demonstrated using a real case study. [ABSTRACT FROM AUTHOR]

Continuous mechanoluminescence (ML) fibers and fiber-woven textiles have the potential to serve as new wearable devices for sensors, healthcare, human—computer interfacing, and Internet of Things. Considering the demands on wearability and adaptability for the ML textiles, it is essential to realize the continuous synthesis of fiber, while maintaining a desired small diameter. Here, we develop a novel adhere-coating method to fabricate ML composite fiber, consisting of a thin polyurethane (PU) core and ZnS:Cu/polydimethylsiloxane (PDMS) shell, with the outer diameter of 120 µm. By diluting PDMS to tune the thickness of liquid coating layer, droplets formation has been effectively prevented. The composite fiber exhibits a smooth surface structure and superior ML performances, including high brightness, excellent flexibility, and stability. In addition, a weft knitting textile fabricated by the continuous ML fiber can be easily delighted by manually stretching, and the ML fibers can emit visible signals upon human motion stimuli when woven into commercial cloth. Such continuous ultra-fine ML fibers are promising as wearable sensing devices for human motion detection and human—machine interactions. [ABSTRACT FROM AUTHOR]

Lead-free copper halide perovskite nanocrystals (NCs) are emerging materials with excellent photoelectric properties. Herein, we present a colloidal synthesis route for orthorhombic Cs2CuCl4 NCs with a well-defined cubic shape and an average diameter of 24 ± 2.1 nm. The Cs2CuCl4 NCs exhibited bright, deep blue photoluminescence, which was attributed to the Cu(II) defects. In addition, passivating the Cs2CuCl4 NCs by Ag+ could effectively improve the photoluminescence quantum yield (PLQY) and environmental stability. [ABSTRACT FROM AUTHOR]

The sesquiterpene alpha-bisabolol is the predominant active ingredient in essential oils that are highly valued in the cosmetics industry due to its wound healing, anti-inflammatory, and skin-soothing properties. Alpha-bisabolol was thought to be restricted to Compositae plants. Here we reveal that alpha-bisabolol is also synthesized in rice, a non-Compositae plant, where it acts as a novel sesquiterpene phytoalexin. Overexpressing the gene responsible for the biosynthesis of alpha-bisabolol, OsTPS1, conferred bacterial blight resistance in rice. Phylogenomic analyses revealed that alpha-bisabolol-synthesizing enzymes in rice and Compositae evolved independently. Further experiments demonstrated that the natural variation in the disease resistance level was associated with differential transcription of OsTPS1 due to polymorphisms in its promoter. We demonstrated that OsTPS1 was regulated at the epigenetic level by JMJ705 through the methyl jasmonate pathway. These data reveal the cross-family accumulation and regulatory mechanisms of alpha-bisabolol production. [ABSTRACT FROM AUTHOR]