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In situ capping and biochemical oxidation are two of the most commonly used methods for internal phosphorus (P) control, but there are few studies on the combined use of these two methods. In this study, two lanthanum (La)-based materials, La-modified bentonite (LMB) and the La-modified attapulgite and chitosan composite (LMA&C), were combined with calcium nitrate (CN) to investigate the effect on sediment P control. Results showed that SRP removal rates by LMB+CN and LMA&C+CN were much higher than that by LMB, LMA&C and CN alone. LMB+CN and LMA&C+CN decreased DGT-labile P flux both in overlying water and surface 65 mm sediment, while LMB and LMA&C had an effect only on overlying water and surface 10~40 mm sediment, and CN was effective only on sediments. LMB and LMA&C transformed NH4Cl-P, BD-P, NaOH-SRP and NaOH-NRP in surface 20 mm sediment to HCl-P and Residual-P on day 60. CN transformed NaOH-SRP and NaOH-NRP to BD-P, resulting in the increase in NH4Cl-P. LMB+CN and LMA&C+CN sequestered P in the surface 20 mm mainly as HCl-P and Residual-P, and mainly as BD-P in −20~−60 mm. Results indicate that the combination of capping by La-based material and oxidation by CN is a promising method for sediment P control. [ABSTRACT FROM AUTHOR]

This investigation focused on the suppressive impact of varying NaHCO3 concentrations on cucumber seed germination and the ameliorative effects of 2,4-Epibrassinolide (EBR). The findings revealed a negative correlation between NaHCO3 concentration and cucumber seed germination, with increased NaHCO3 concentrations leading to a notable decline in germination. Crucially, the application of exogenous EBR significantly counteracted this inhibition, effectively enhancing germination rates and seed vigor. Exogenous EBR was observed to substantially elevate the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), thereby mitigating oxidative damage triggered under NaHCO3 stress conditions. Additionally, EBR improved enzyme activity under alkaline stress conditions and reduced starch content in the seeds. Pertinently, EBR upregulated genes that were associated with gibberellin (GA) synthesis (GA20ox and GA3ox), and downregulated genes that were linked to abscisic acid (ABA) synthesis (NCED1 and NCED2). This led to an elevation in GA3 concentration and a reduction in ABA concentration within the cucumber seeds. Therefore, this study elucidates that alleviating oxidative stress, promoting starch catabolism, and regulating the GA and ABA balance are key mechanisms through which exogenous EBR mitigates the suppression of cucumber seed germination resulting from alkaline stress. [ABSTRACT FROM AUTHOR]

Although fluorinated porous materials are considered promising candidates due to their high porosity, low density and acid and alkali resistance, they still face several challenges, such as complex preparation methods, heat‐induced polymerization of fluorinated emulsion taking too long and material brittleness. In this study, we avoided the difficult problem of stability of fluorine‐containing emulsions. We prepared functional hydrophobic hyperelastomers with morphological control, excellent oil absorption and recyclability by thiol–ene click photopolymerization using a water‐in‐oil high internal phase emulsion as template. The oil absorption capacity of the B4‐30%Si sample did not change after 10 recycles. By combining the advantages of organic fluorine and inorganic silicon, the prepared foam retains hydrophobicity and excellent chemical resistance, and has excellent structural and mechanical properties and can be compressed up to a 90% strain without rupture. Finally, the composite porous material B4‐30%Si has greater thermal stability (up to 280 °C) than commercially available polypropylene separators, due to the introduction of fluorine and silicon, and better flexibility and mechanical strength than glass fiber separators. Therefore, these materials are promising for use in lithium–sulfur batteries and wearable electronic components after further modification. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Poplar is a major afforestation species which is widely planted worldwide. With the continuous expansion of poplar plant areas, the occurrence of poplar canker disease increased rapidly, causing serious damage to the trees. Currently, the major controlling method for poplar canker is chemical agents, but side effects such as environmental pollution and pathogen resistance are becoming more and more serious. There is an urgent need for developing effective non-polluting means to control the canker disease. By using microbiomes as a research tool, beneficial microorganisms that enhance plant disease resistance can be obtained. These antagonistic bacteria can inhibit the growth of canker pathogens without environmental pollution, and have good biological-control potential. This review mainly explores the role and mechanisms of antagonistic bacteria in the control of poplar canker, including inhibiting the growth of pathogenic bacteria through nutrient and water competition, secreting bacteriostatic substances, improving plant disease resistance to resist pathogen infection, and improving the host's own reactive oxygen species tolerance, in order to provide a theoretical basis for the development of efficient and specific bacterial agents, and scientific prevention and control technology. [ABSTRACT FROM AUTHOR]

Instrumentation packages for eddy covariance (EC) measurements have been developed for unoccupied aerial vehicles (UAVs) to measure the turbulent fluxes of latent heat (LE), sensible heat (H), and CO2 (Fc) in the atmospheric boundary layer. This study aims to evaluate the performance of this UAV-based EC system. First, the measurement precision (1σ) of georeferenced wind was estimated to be 0.07 ms-1. Then, the effect of the calibration parameter and aerodynamic characteristics of the UAV on wind measurement was examined by conducting a set of calibration flights. The results showed that the calibration improved the quality of the measured wind field, and the influence of upwash and the leverage effect can be ignored in wind measurement by the UAV. Third, for the measurements of turbulent fluxes, the error caused by instrumental noise was estimated to be 0.03 µmolm-2s-1 for Fc , 0.02 Wm-2 for H , and 0.08 Wm-2 for LE. Fourth, data from the standard operational flights were used to assess the influence of resonance on the measurements and to test the sensitivity of the measurement under the variation (±30 %) in the calibration parameters around their optimum value. The results showed that the effect of resonance mainly affected the measurement of CO2 (∼5 %). The pitch offset angle (εθ) significantly affected the measurement of vertical wind (∼30 %) and turbulent fluxes (∼15 %). The heading offset angle (εψ) mainly affected the measurement of horizontal wind (∼15 %), and other calibration parameters had no significant effect on the measurements. The results lend confidence to the use of the UAV-based EC system and suggest future improvements for the optimization of the next-generation system. [ABSTRACT FROM AUTHOR]

There are many complicated factors affecting sawing of wood structural component, so it is difficult to measure and evaluate accurately. In this study, the sawing speed of the wood component, the tooth shape of the circular saw blade, the number of teeth, and the wood component material were selected as the test factors to explore their influence on the sawing performance. Based on the multi-factor orthogonal test analysis method, the visual analysis method was used to comprehensively explore the impact of rotary speed of 1 000, 2 000, 3 000 r/min, circular saw blade flat teeth, ladder flat teeth, left and right teeth, number of teeth 60, 96, 120, spruce, fiberboard and bamboo scrimber on the cutting performance of wood components. The sawing-cutting power of wood components was used as the evaluation index of sawing-cutting performance of wood components, and multiple groups of experimental analysis were carried out to determine the best sawing scheme of wood components under different materials. The results showed that: 1) the primary and secondary order of the influence of each test factor on the maximum power consumption in the sawing process was: circular saw blade speed, specimen material, circular saw blade teeth number, circular saw blade teeth shape. The optimal process for sawing spruce was 1 000 r/min, 60 teeth and flat tooth shape. 2) The optimal process for sawing fiberboard was 1 000 r/min, 96 teeth and ladder flat teeth. 3) The optimal process for sawing bamboo scrimber was 2 000 r/min, 60 teeth and flat tooth shape. [ABSTRACT FROM AUTHOR]