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• This study employs the GDIM model and the ARDL method to examine several key drivers of agricultural carbon emissions in the main grain-producing areas of China. • Despite being a significant factor in agricultural carbon emissions, the impact of chemical fertilizer input shifted from a rising to a falling trend, confirming the existence of an agriculture-based CO2 EKC. • Agricultural mechanical application had a long-term inhibiting effect, while the aging of the agricultural labor force had a short-term driving effect. Low-carbon agricultural development is inseparable from the support of green finance. This study utilizes the GDIM model and the ARDL method to examine several key drivers of agricultural carbon emissions in China's main grain-producing areas from 2000 to 2020. The objective is to offer a valuable policy framework for green finance in promoting low-carbon agricultural production. The results indicated that despite being a driving factor in agricultural carbon emissions, the effect of the chemical fertilizer input shifted from rising to falling, and an agriculture-based CO 2 EKC was confirmed. Moreover, from the perspective of the causal links between agricultural carbon emissions and their drivers, this study found that chemical fertilizer input had both long- and short-term driving effects, agricultural mechanical application had a long-term inhibiting effect, and the aging of the agricultural labor force had a short-term driving effect. The findings of this paper will help policymakers develop green financial resources to guide capital towards low-carbon agricultural production. [ABSTRACT FROM AUTHOR]

Background: Radiotherapy inadvertently affects gastrointestinal (GI) epithelial cells, causing intestinal barrier disruption and increased permeability.Objective: We examined the effect of amino acid-based oral rehydration solution (AA-ORS) on radiation-induced changes of intestinal barrier function and epithelial tight junctions (TJs) in a randomized experimental study using a total-body irradiation (TBI) mouse model.Methods: Eight-week-old male Swiss mice received a single-dose TBI (0, 1, 3, or 5 Gy), and subsequent gastric gavage with AA-ORS (threonine, valine, serine, tyrosine, and aspartic acid) or saline for 2 or 6 d. Intestinal barrier function of mouse ileum was characterized by electrophysiological analysis of conductance, anion selectivity, and paracellular permeability [fluorescein isothiocyanate (FITC)-dextran]. Ultrastructural changes of TJs were evaluated by transmission electron microscopy. Membrane protein and mRNA expression of claudin-1, -2, -3, -5, and -7, occludin, and E-cadherin were analyzed with western blot, qPCR, and immunohistochemistry. Nonparametric tests were used to compare treatment-dose differences for each time point.Results: Saline-treated mice had a higher conductance at doses as low as 3 Gy, and as early as 2 d post-TBI compared with 0 Gy (P < 0.001). Paracellular permeability and dilution potential were increased 6 d after 5 Gy TBI (P < 0.001). Conductance decreased with AA-ORS after 2 d in 3-Gy and 5-Gy mice (P < 0.05 and P < 0.001), and on day 6 after 5 Gy TBI (P < 0.001). Anion selectivity and FITC permeability decreased from 0.73 ± 0.02 to 0.61 ± 0.03 pCl/pNa (P < 0.01) and from 2.7 ± 0.1 × 105 to 2.1 ± 0.1 × 105 RFU (P < 0.001) in 5-Gy mice treated with AA-ORS for 6 d compared with saline. Irradiation-induced ultrastructural changes of TJs characterized by decreased electron density and gap formation improved with AA-ORS. Reduced claudin-1, -3, and -7 membrane expression after TBI recovered with AA-ORS within 6 d, whereas claudin-2 decreased indicating restitution of TJ proteins.Conclusions: Radiation-induced functional and structural disruption of the intestinal barrier in mice is reversed by AA-ORS rendering AA-ORS a potential treatment option in prospective clinical trials in patients with gastrointestinal barrier dysfunction. [ABSTRACT FROM AUTHOR]

Disposable aluminum cans and plastic bottles are common wastes found in modern societies. This article shows that they can be upcycled into functional materials, such as metal-organic frameworks and hierarchical porous carbon nanomaterials for high-value applications. Through a solvothermal method, used poly(ethylene terephthalate) bottles and aluminum cans are converted into MIL-53(Al). Subsequently, the as-prepared MIL-53(Al) can be further carbonized into a nitrogen-doped (4.52 at%) hierarchical porous carbon framework. With an optical amount of urea present during the carbonization process, the carbon nanomaterial of a high specific surface area of 1324 m2 g−1 with well-defined porosity can be achieved. These features allow the nitrogen-doped hierarchical porous carbon to perform impressively as the working electrode of supercapacitors, delivering a high specific capacitance of 355 F g−1 at 0.5 A g−1 in a three-electrode cell and exhibiting a high energy density of 20.1 Wh kg−1 at a power density of 225 W kg−1, while simultaneously maintaining 88.2% capacitance retention over 10,000 cycles in two-electrode system. This work demonstrates the possibility of upcycling wastes to obtain carbon-based high-performance supercapacitors. [Display omitted] • Upcycle used PET bottles and aluminum cans into the nitrogen-doped hierarchical porous carbons. • Prepared carbon as supercapacitor electrode delivers a high energy density of 20.1 Wh/kg. • Well-defined porous carbon framework is vital to the excellent supercapacitive performance. • This work paves an effective environmental-friendly way to prepare carbon-based supercapacitor. [ABSTRACT FROM AUTHOR]

Abstract The thickness dependency of trans-laminar fracture toughness was studied in centre-notched quasi-isotropic IM7/8552 carbon/epoxy laminates with central double 0° plies with thicknesses between 1 and 8 mm. A reduction in trans-laminar fracture toughness with thickness was measured experimentally in the specimens with a 25.4 mm notch. For specimens with a shorter 12.7 mm notch, no significant dependency on specimen thickness was found. The thickness dependency was captured in detailed Finite Element (FE) models with cohesive interface elements for sub-critical damage and a Weibull criterion for fibre breakage. The reason for the thickness dependency is explained through the damage states of the individual plies which determine whether or not premature fracture occurs before the damage process zone is fully developed. [ABSTRACT FROM AUTHOR]

Abstract In large spaces, co-operative HVAC terminals are usually installed to provide services for different virtual thermal zones. The lack of high-resolution occupancy distribution in large spaces is often perceived as one of the main causes of underperformed HAVC systems. Current studies usually considered occupancy information of the whole space or room, such as occupancy count level, other than the zone-level occupancy distribution. Although the count of total occupants in space might stay constant, the actual occupancy distribution might be different, which will bring with different operations for each HVAC terminal. Therefore, to find out one high-resolution occupancy level, this research proposed the idea of integrating k-Means clustering and k Nearest Neighbors (kNN) classification algorithm to detect the occupancy distribution via the dual Bluetooth Low Energy (BLE) and Wi-Fi signal technology networks. One experiment place was conducted in one indoor area of the typical office room at the City University of Hong Kong for measuring the signal distribution of BLE and Wi-Fi. In this study, the occupancy preference cluster could be mapped into the indoor thermal zones and three case studies are chosen for validation of occupant number confirmation in each thermal zone. Finally, zone occupancy based energy performance analysis was presented with the assistance of wireless sensors nodes to compare energy saving potential under actual occupancy distribution and detected occupancy distribution and the importance of zone occupancy information for the demand-driven control mechanism is stressed. [ABSTRACT FROM AUTHOR]

Mode II fracture energy, G IIC , is a critical parameter for determining the propagation of delamination in composite laminates. Its value can be affected by Through-Thickness Compression (TTC) stress acting on the crack tip and here this effect has been studied using IM7/8552 carbon/epoxy laminates with cut central plies. External TTC loads were applied through bi-axial testing. Unidirectional (UD) cut-ply specimens were used to determine the TTC enhancement factor, η G , for G IIC . A similar enhancement effect was also found in Quasi-isotropic (QI) specimens with 2 extra cut central 0° plies inserted into the layup. The TTC enhancement factor was implemented in a Finite Element Analysis (FEA) framework using cohesive interface elements, showing that the determined η G can be successfully used to model the effect of TTC on delamination. [ABSTRACT FROM AUTHOR]

The initial fracture propagation within a full-scale stiffened quasi-isotropic composite panel and coupons with stringer feet under tensile loads was investigated. The specimens were made from Non-Crimp Fabric through Vacuum assisted Resin Transfer Moulding. The failure loads of all configurations were successfully related using the same value of trans-laminar fracture energy. The method involved independent tests of scaled-down Over-height Compact Tension specimens and the Virtual Crack Closure Technique. It was found to be crucial to include the fully developed damage process zone in the crack length and to interpret the results carefully in order to identify the failure loads consistently. [ABSTRACT FROM AUTHOR]

Transparent Sm:Y 2 O 3 ceramics were fabricated by spark plasma sintering (SPS). The effects of LiF additive and sintering temperature on the microstructure and optical transmittance of the Sm:Y 2 O 3 ceramics were investigated. The optimal content of LiF additive and sintering temperature was found to be 0.3 wt% and 1500 ℃. The transmittance of Sm:Y 2 O 3 ceramics with a thickness of 1.7 mm reached 75.3% at 609 nm, which is about 94% of the theoretical value. The average grain size of the sample was about 50 µm. [ABSTRACT FROM AUTHOR]