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To achieve better mechanical properties and higher scour resistance of yellow mud in Qiang Village, this study investigated how to improve yellow mud by single factors of straw, starch, cement, and epoxy resin. First, the effect of each material on the shear strength of yellow mud was analyzed through the direct shear test, and the effect of the respective material on the scour resistance of yellow mud was examined using a self-made spray device. Subsequently, combined with the results of the two experiments, the improvement effect of the material was comprehensively studied, and the optimal dosage of the respective material was determined. Lastly, an electron microscope was used to observe the microscopic morphology of the samples, and the improvement mechanism of each material was discussed from qualitative and quantitative perspectives. As revealed by the results, straw, starch, cement, and epoxy resin improved the shear strength and scour resistance of yellow mud. Peaks of straw, starch, and epoxy resin were found in their corresponding properties-dosage curves, corresponding to the optimal dosage in the experimental range. The corresponding performance curve of cement showed a unidirectional change, which was found with a significant improvement effect.

More than 2 billion people around the world still use raw earth architecture, in countries like Nepal, India, and Iran. In China, the proportion of people living in earthen structures rose to 36%, some of them in western Sichuan. Minority dwellings in western Sichuan, China, use local stone and yellow mud as building materials and have been used for thousands of years. Because yellow mud is a brittle material with poor mechanical properties, and because the region is prone to earthquakes, the walls are highly susceptible to damage under seismic action. To improve the mechanical properties of yellow mud, the yellow mud of Taoping Qiang Village in western Sichuan was studied and modified. Uniaxial compressive tests were conducted on the modified specimens, and the existing ontogenetic equations of raw soil-based materials were analyzed and optimized. Finally, we developed the constitutive models for yellow clay and modified yellow clay in the western Sichuan area, which can be used for different kinds of modified materials through the variation of parameters. The results show that the compressive strength of yellow clay is improved by adding the modified materials. The optimized constitutive model can better fit the test curves, which can provide a basis for theoretical calculations and seismic mitigation of minority residential structures in western Sichuan or similar structural systems.

Methane is a major contributor to anthropogenic greenhouse gas emissions. Identifying large sources of methane, particularly from the oil and gas sectors, will be essential for mitigating climate change. Aircraft-based methane sensing platforms can rapidly detect and quantify methane point-source emissions across large geographic regions, and play an increasingly important role in industrial methane management and greenhouse gas inventory. We independently evaluate the performance of five major methane-sensing aircraft platforms: Carbon Mapper, GHGSat-AV, Insight M, MethaneAIR, and Scientific Aviation. Over a 6 week period, we released metered gas for over 700 single-blind measurements across all five platforms to evaluate their ability to detect and quantify emissions that range from 1 to over 1,500 kg(CH4)/h. Aircraft consistently quantified releases above 10 kg(CH4)/h, and GHGSat-AV and Insight M detected emissions below 5 kg(CH4)/h. Fully blinded quantification estimates for platforms using downward-facing imaging spectrometers have parity slopes ranging from 0.76 to 1.13, with R2 values of 0.61 to 0.93; the platform using continuous air sampling has a parity slope of 0.5 (R2 = 0.93). Results demonstrate that aircraft-based methane sensing has matured since previous studies and is ready for an increasingly important role in environmental policy and regulation.

Abstract. Satellite-based remote sensing enables detection and mitigation of large point sources of climate-warming methane. These satellites will have the greatest impact if stakeholders have a clear-eyed assessment of their capabilities. We performed a single-blind test of nine methane-sensing satellites from three continents and five countries, including both commercial and government satellites. Over 2 months, we conducted 82 controlled methane releases during satellite overpasses. Six teams analyzed the resulting data, producing 134 estimates of methane emissions. Of these, 80 (58 %) were correctly identified, with 46 true positive detections (34 %) and 34 true negative non-detections (25 %). There were 41 false negatives, in which teams missed a true emission, and 0 false positives, in which teams incorrectly claimed methane was present. All eight satellites that were given a nonzero emission detected methane at least once, including the first single-blind evaluation of the EnMAP, Gaofen 5, and Ziyuan 1 systems. In percent terms, quantification error across all satellites and teams is similar to aircraft-based methane remote sensing systems, with 55 % of mean estimates falling within ±50 % of the metered value. Although teams correctly detected emissions as low as 0.03 metric tons of methane per hour, it is unclear whether detection performance in this test is representative of real-world field performance. Full retrieval fields submitted by all teams suggest that in some cases it may be difficult to distinguish true emissions from background artifacts without a known source location. Cloud interference is significant and appears to vary across teams and satellites. This work confirms the basic efficacy of the tested satellite systems in detecting and quantifying methane, providing additional insight into detection limits and informing experimental design for future satellite-focused controlled methane release testing campaigns.

Accumulative behavioural and electrophysiological evidence has demonstrated the effects of sentence context on word processing. However, there is insufficient research investigating both global and local effects during processing. A Chinese classifier can select or exclude some nouns, and it is obligatorily used with numerals or demonstratives (e.g., “this” and “that”) to specify the quantity of an object or identify particular objects. There is no study that manipulated the congruency of Chinese classifiers to look at this local effect on processing the head nouns. In this study, we employed the EEG technique to investigate the prenominal prediction effect and, more importantly, to look at whether an incongruent classifier is strong enough to disconfirm a prediction generated by a highly constraining sentence. Highly constraining sentences were built and tested through a probability pre-test, and the probabilities of congruent head nouns of the sentences are all above 50%. We manipulated the congruency between global sentence context and head nouns, as well as the congruency between classifiers and head nouns in those highly constraining Chinese sentences using a two-by-two factorial design. The results revealed that the semantic and grammatical features of highly predicted nouns can be pre-activated prior to the bottom-up input of the head nouns. This effect is already visible at the classifier position as the N400 amplitude of an incongruent classifier is larger than that of a congruent classifier. In addition, both global sentence context and local classifier-noun congruency significantly influence head noun processing to the extent that neither factor exhibits overwhelming strength over the other, as indicated by the N400 amplitudes of the head nouns. Furthermore, both global and local information can be integrated during early lexical processing.

Bioelectronics is a hot research topic, yet an important tool, as it facilitates the creation of advanced medical devices that interact with biological systems to effectively diagnose, monitor and treat a broad spectrum of health conditions. Electrical stimulation (ES) is a pivotal technique in bioelectronics, offering a precise, non-pharmacological means to modulate and control biological processes across molecular, cellular, tissue, and organ levels. This method holds the potential to restore or enhance physiological functions compromised by diseases or injuries by integrating sophisticated electrical signals, device interfaces, and designs tailored to specific biological mechanisms. This review explains the mechanisms by which ES influences cellular behaviors, introduces the essential stimulation principles, discusses the performance requirements for optimal ES systems, and highlights the representative applications. From this review, we can realize the potential of ES based bioelectronics in therapy, regenerative medicine and rehabilitation engineering technologies, ranging from tissue engineering to neurological technologies, and the modulation of cardiovascular and cognitive functions. This review underscores the versatility of ES in various biomedical contexts and emphasizes the need to adapt to complex biological and clinical landscapes it addresses. [ABSTRACT FROM AUTHOR]

Utilizing plasmonic effects to assist electrochemical reactions exhibits a huge potential in tuning the reaction activities and product selectivity, which is most appealing especially in chemical reactions with multiple products, such as CO2 reduction reaction (CO2RR). However, a comprehensive review of the development and the underlying mechanisms in plasmon-assisted electrocatalytic CO2RR remains few and far between. Herein, the fundamentals of localized surface plasmonic resonance (LSPR) excitation and the properties of typical plasmonic metals (including Au, Ag, and Cu) are retrospected. Subsequently, the potential mechanisms of plasmonic effects (such as hot carrier effects and photothermal effects) on the reaction performance in the field of plasmon-assisted electrocatalytic CO2RR are summarized, which provides directions for the future development of this field. It is concluded that plasmonic catalysts exhibit potential capabilities in enhancing CO2RR while more in situ techniques are essential to further clarify the inner mechanisms. [ABSTRACT FROM AUTHOR]

Spallation fracture in ductile metals with low melting points is an important scientific concern of dynamic fracture. Classical spallation and micro-spallation simulations of single crystal (SC) and nanocrystalline (NC) tin were carried out using non-equilibrium molecular dynamics at shock pressures of 13.5–61.0 GPa. The shock wave velocity had no effect on the waveform evolution in the SC Sn but not in the NC Sn. The front width of the stress wave in the classical spallation of the NC Sn was predominantly affected by grain boundary sliding. The atomic trajectory technique was first introduced to reproduce the evolutionary processes of void growth and coalescence quite effectively. In the classical spallation, the differences in void evolution behavior of SC and NC Sn were mainly reflected in nucleation position, spatial distribution, and growth zone, while their evolutionary behaviors were shared in the micro-spallation. In the NC model, for the classic spallation, voids mostly nucleated at grain boundaries and grew along grain boundaries, resulting in intergranular fractures; for the micro-spallation, voids nucleated at the grain boundary and inside the grain, resulting in intergranular, intragranular, and transgranular fractures. Furthermore, the void volume fraction followed the bilinear rise at the early nucleation and growth stages, and the critical transition point fundamentally signified the initiation of void nucleation to growth. [ABSTRACT FROM AUTHOR]