Two cores were selected in the Changjiang Estuary and its adjacency,one within the region of seasonal hypoxia and the other nearby but outside the hypoxia *** major elements,trace elements and rare earth elements(REEs...
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Two cores were selected in the Changjiang Estuary and its adjacency,one within the region of seasonal hypoxia and the other nearby but outside the hypoxia *** major elements,trace elements and rare earth elements(REEs)were determined on the 210Pb-dated sediment *** distributions of most elements in the core sediment outside the hypoxia region were controlled by “grain size effects”.In the core sediment within the hypoxia region,some redox sensitive elements(RSEs)just like the Mo,Cd,As et *** been enriched significantly,which concentrations increased about 83%,73%and 50%respectively since the late 1960s to *** the Mn has been depleted since *** results indicate the redox environment of the bottom water-sediment interface has been changed which might be caused by the eutrophication and hypoxia in the Changjiang *** concentrations of biogenic elements as well as Ca,Sr,P have also increased about 129%,65%and 38%respectively since the late 1960s,which reflected the increasing of productivity and biomass influenced by the anthropogenic activities during the last forty *** results showed that the contents of biogenic elements as well as Ca,Sr,P and some RSEs just like Mo,Cd,As,Mn in sediment could be used to trace or reconstruct history of the coastal eutrophication and hypoxia in the high productivity zone in the Changjiang Estuary over the last 100 *** were correlated negatively with Ti,Al,Fe and no obvious relation with grain *** decreasing trend of δCe distribution over the last 100 years may be related to the progressive hypoxia and high productivity in the Changjiang *** geochemical parameters gave the same conclusions consistently: effected by the anthropogenic activity,the Changjiang estuary hypoxia began in 1970s and showed the increasing trend.
BACKGROUNDIn the present study, we address the quality degradation of corn during post-harvest processing by developing a viscoelastic composite model to predict kernel damage during post-harvest processing. The model...
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BACKGROUNDIn the present study, we address the quality degradation of corn during post-harvest processing by developing a viscoelastic composite model to predict kernel damage during post-harvest processing. The model, based on high-resolution scanning and inverse modeling techniques, provides an accurate representation of the complex internal components of corn kernels, which allows for the analysis of their stress response and damage susceptibility trends under different impact *** results show that the viscoelastic model has a relative error of 2.4% compared to the drop test data, thus demonstrating that the viscoelastic model has a very high accuracy in predicting impact damage and is able to accurately localize the flour-like endosperm as the main region of impact damage. The model showed a high correlation (0.99) between predicted and experimental damage rates by response surface *** damage during processing is reduced by reducing the proportion of flour-like endosperm in maize kernels. A new method for reducing damage during food handling and processing operations is proposed, providing an important reference for improving kernel durability and contributing to the development of gentler processing techniques to improve the quality of maize products. (c) 2025 Society of Chemical Industry.
The reactive oxygen species (ROS) triggered by peroxymonosulfate (PMS), primarily composed of radicals and nonradicals, can deeply and selectively remove pollutants in complex wastewater. However, the low efficiency o...
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The reactive oxygen species (ROS) triggered by peroxymonosulfate (PMS), primarily composed of radicals and nonradicals, can deeply and selectively remove pollutants in complex wastewater. However, the low efficiency of electron transfer and insufficient surface catalytic sites remain the main obstacles to the development of efficient and selective PMS activators. Herein, we constructed ABO(3) perovskite catalysts (LaCoO3) with adjustable La vacancies (V-La) densities through urea introduction. Experiment, characterization, and theoretical calculation jointly revealed that VLa could not only induce electron delocalization in Co site to enhance the Co 3d - O 2p covalency for accelerating ROS (sulfate radicals (SO4 center dot-), singlet oxygen (O-1(2)), and high valent cobalt (Co(IV) = O)) generation, but also trigger the transition of spin-polarization configuration to form Co3+ (t(2g)(5)e(g)(1)) with the intermediate spin state as new active sites for surface-bound PMS* complexes production. The nonradical-dominated and radical-assisted system containing multi-site achieved efficient PMS utilization (95.6 %), excellent decontamination activity (0.753 min(-1)), good mineralization ability (82.7 %), satisfactory acid-base resistance (working pH range 3-11), and environmental robustness for actual water treatment. This study reveals the role of cation vacancy engineering in achieving "Two birds one stone" for PMS activation at the atomic level, which will guide the rational design of Fenton-like catalysts.
The plant cuticle is a complex mixture of omnipresent, commonly monofunctional, fatty acid derivatives and taxon-specific, generally bifunctional, specialty compounds. This study explored expanded applications for the...
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The plant cuticle is a complex mixture of omnipresent, commonly monofunctional, fatty acid derivatives and taxon-specific, generally bifunctional, specialty compounds. This study explored expanded applications for these substances. Four types of plant cuticles were distilled from leaves and the resulting lipid mixtures were analyzed using gas chromatography-mass spectrometry. These were then used as additives for a synthetic ester lubricant. A reciprocating friction and wear testing machine was utilized to investigate the resulting tribological properties. The worn surfaces of the lower discs were observed and analyzed using optical microscopy and time-of-flight secondary ion mass spectrometry. The results reveal that cuticular waxes can modify the friction properties of the base oil. Furthermore, cuticular waxes demonstrate better performance when compared to the commercially available additive molybdenum dithiocarbamates. A protective adsorption film was identified as the reason for the improved friction reduction and anti-wear properties of the lubricant on the friction pair. This study provides a reference for the study of new types of non-sulfur, phosphorus, and other active element additives and demonstrates considerable potential for the economical utilization of plant leaf waxes.
Polydopamine is widely used in surface modification, nanofiltration, photonic devices and drug delivery. The formation mechanism and properties of polydopamine are modified by the experimental conditions. Herein we de...
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Polydopamine is widely used in surface modification, nanofiltration, photonic devices and drug delivery. The formation mechanism and properties of polydopamine are modified by the experimental conditions. Herein we demonstrated a comparison study of free-standing polydopamine films generated at the air-solution interface and their corresponding nanoparticles in solutions, in the presence of various metallic cations, Na+, Ca2+, Mg2+ and Co2+. Adding metallic ions influenced the intermediates in dopamine polymerization, and in turn the morphology and properties of the produced free-standing polydopamine films. Moreover, we observed that the polymerization process accompanying the stratification determines the formation of free-standing films at the air-solution interface: the fast polymerization of dopamine in a Co2+ environment leads to a rugged film surface and porous film body, whereas the comparatively slow polymerization of dopamine under conditions of other metallic ions results in a smooth and solid film. In addition, the water contact angles of the upper and lower surface of the polydopamine films were different. This investigation enriches our knowledge of dopamine polymerization in different environments, which is particularly useful for further application of free-standing polydopamine films.
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