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BACKGROUND: This study examined the changes in soil fertility in a maize cropping area when chemical fertilizer was partially replaced with straw or livestock manure over a 33-year period. Four treatments were included: (i) CK (no fertilizer application); (ii) NPK (only chemical fertilizer application); (iii) NPKM (chemical fertilizer partly replaced with livestock manure); (iv) NPKS (chemical fertilizer partly replaced with straw). RESULTS: Soil organic carbon increased by 41.7% and 95.5% in the NPKS and NPKM treatments, respectively, over the 33-year trial compared with the initial concentration. However, soil organic carbon in NPK was significantly reduced by 9.8%. Soil total N, P and K increased in both NPKM and NPKS treatments compared to the original soil. Soil pH was significantly acidified from 7.6 to 5.97 in the NPK treatment during the experimental period. The NPKM and NPKS treatments buffered the acidification compared to NPK. Meta-analysis results showed that, compared with NPK, NPKM significantly raised soil bacteria and fungi populations by 38.7% and 58.6%; enhanced microbial biomass carbon and nitrogen by 66.3% and 63%, respectively; and increased sucrase, urease and catalase activities by 34.2%, 48.2% and 21.5%. NPKS significantly increased soil fungi and actinomycetes populations by 24.3% and 41.2%, respectively; enhanced microbial biomass carbon and nitrogen by 27.1% and 45%; and strengthened sucrase and urease activities by 36% and 20.3%, respectively. CONCLUSION: Long-term chemical fertilizer application led to the deterioration of soil fertility and environment. Partial replacement of chemical fertilizers with organic materials could significantly amend and buffer such negative effects. © 2023 Society of Chemical Industry.
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Fertilizantes , Solo , Fertilizantes/análise , Agricultura , Esterco/análise , Carbono/análise , Urease , Nitrogênio/análise , Sacarase , ChinaRESUMO
The morphology of W18O49 catalysts has a significant effect on their photocatalytic performance. Herein, we successfully prepared two commonly used W18O49 photocatalysts just by changing the reaction temperature in the hydrothermal system, namely 1-D W18O49 nanowires (1-D W18O49) and 3-D urchin-like W18O49 particles (3-D W18O49), and evaluated the difference of their photocatalytic performances by taking the degradation of methylene blue (MB) as an example. Remarkably, 3-D W18O49 exhibited an impressive photocatalytic degradation performance towards MB with photocatalytic reaction rates of 0.00932 min-1, which was about 3 times higher than that of 1-D W18O49. The comprehensive characterization and control experiments could further reveal that the hierarchical structure of 3-D W18O49 brought higher BET surface areas, stronger light harvesting, faster separation of photogenerated charges and so on, which was the main reason for its better photocatalytic performance. ESR results confirmed that the main active substances were superoxide radicals (ËO2 -) and hydroxyl radicals (ËOH). This work aims to explore the intrinsic relationship between the morphology and photocatalytic properties of W18O49 catalysts, so as to provide a theoretical basis in the morphology selection of W18O49 or its composite materials in the field of photocatalysis.
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BACKGROUND: The availability of soil nitrogen (N) decreases as the structure of agricultural soils degrades. Traditional methods focus on organic amendments that indirectly affect the porosity and N content of soil. Due to the low efficiency of such amendments, new materials, particularly highly porous materials, are needed to improve the quality of soil, which has opened new directions. RESULTS: The addition of 2 to 7 mm of porous clay ceramic (PLC) significantly increased the fresh weight of Brassica chinensis. The soil aeration porosity (>50 µm) increased by 0.69% on average in response to 1% PLC application. Soil NO3 - -N, NH4 + -N and mineral N increased by 3.3, 1.3 and 4.6 mg kg-1 on average, respectively, following a 1% PLC application rate. The initial N content of the high PLC treatments was the lowest in the incubation experiment. The parameters of soil N mineralization, i.e. potentially mineralizable N (N0 ), the first-order rate constant (k) and the mineralization composite index (N0 × k), increased obviously as the amount of PLC increased. Porosities larger than 1000 µm were significantly more positively correlated with the parameters of soil N mineralization than those <500 µm. The Pearson correlation coefficients suggested that high porosity, mineral N and N0 values had significant positive relationships with the fresh weights in double seasons. CONCLUSION: The application of PLC increased soil aeration and enhanced the availability of soil N, which yielded large vegetable harvests in clayey soils in the short term. © 2022 Society of Chemical Industry.
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Nitrogênio , Solo , Argila , Minerais , Nitrogênio/metabolismo , Porosidade , Solo/químicaRESUMO
Anisotropic nanostructures can be generated in fused silica glass by manipulating the spatiotemporal properties of a picosecond pulse. This phenomenon is attributed to laser-induced interband self-trapped excitons. The anisotropic structures exhibit birefringent properties, and thus can be employed for multi-dimensional optical data storage applications. Data voxels generated by such short laser irradiation enable on-the-fly high-speed data recording.
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In situ fluorophores were induced on polyvinyl alcohol (PVA) bulk materials by direct femtosecond laser writing. The generation of fluorophores was ascribed to localized laser-assisted carbonization. The carbonization of PVA polymers was confirmed through X-ray photoelectron spectroscopy analysis. The distinct fluorescence responses of fluorophores in various solutions were harnessed for implementing in situ reagent sensors, metal ion sensors, data encryption, and data security applications. The demonstrated water detection sensor in acetone exhibited a sensitivity of 3%. Meanwhile, a data encryption scheme and a "burn after reading" technique were demonstrated by taking advantage of the respective reversible and irreversible switching properties of the in situ laser-induced fluorophores. Taking a step further, a quantitative cobalt ion measurement was demonstrated based on the concentration-dependent fluorescence recovery. Combined with a laser-induced hydrophilic modification, our scheme could enable "lab-on-a-chip" microfluidics sensors with arbitrary shape, varied flow delay, designed reaction zones, and targeted functionalities in the future.
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Herein, a flexible four-dimensional optical data storage technique is demonstrated by harnessing ultrafast laser-induced fluorophores in thermoplastic polyurethane. By modulating the pulse energy of a 515 nm laser, data voxels with multilevel fluorescence signals can be generated and encoded. The readout accuracy of the encoded multilayer information remains at 92.2% after 50 bending cycles, demonstrating the feasibility of our technology for data recording based on a roll-to-roll method. The generation of fluorophores by only a single femtosecond laser pulse provides the ability to record data beyond 20 MB/s.
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BACKGROUND: 3,4-Dimethylpyrazole phosphate (DMPP) is a nitrification inhibitor which can restrict nitrate (NO3 - ) production. Boric acid is a substance which inhibits urease activity. However, few studies have focused on the inhibitory effect of boric acid on urea hydrolysis and the possible synergistic effect with DMPP. Thus, an incubation trial was conducted to determine the impact of boric acid and DMPP addition on urea-N transformation, and their synergistic effects, in chernozem soil (Che) and red soil (RS). Four treatments were set up in each soil: urea only (U); urea combined with DMPP (UD); urea combined with boric acid (UB); and urea combined with both DMPP and boric acid (UDB). RESULTS: Compared to U, adding DMPP (UD) increased NH3 emissions by 11% and 13% and decreased soil NO3 - -N concentration by 38% and 13% in Che and RS, respectively. Boric acid addition (UB) effectively prolonged the half-life time of urea by 0.8 and 0.4 days, reduced NH3 volatilizations by 11% and 16% and delayed the occurrence of NH3 emission peaks for 3 and 4 days in contrast to U treatment in Che and RS, respectively. UDB treatment mitigated the NH3 volatilizations caused by the addition of DMPP (UD) by 16% and 29% in Che and RS, respectively. Additionally, a better nitrification inhibition rate was found in the UDB treatment compared to other treatments in both soils. CONCLUSIONS: There is potential to develop a new N transformation inhibition strategy with the use of a combination of boric acid and DMPP. © 2020 Society of Chemical Industry.
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Ácidos Bóricos/química , Pirazóis/química , Ureia/química , Amônia/química , Fertilizantes/análise , Cinética , Nitratos/química , Nitrificação , Solo/químicaRESUMO
Oxidative stress has been proposed to contribute to DNA damage and is involved in many neurodegenerative diseases. It has been reported that Aralia elata (Miq.) Seem. (A. elata) exhibits an anti-oxidative effect but the mechanisms underlying this protective effect are still unclear. In this study, six known triterpene saponins were isolated from the buds of A. elata, a well-known medicinal and edible plant in Northeast China. Subsequently, the anti-oxidative effects of all six triterpene saponins were screened by H2O2-induced damage in human neuronblastoma SH-SY5Y cells. Compound 6, also known as Eclalbasaponin I (EcI), was the most potent. Furthermore, the mechanism by which EcI combats H2O2-induced oxidative stress was investigated. The data suggested that EcI could down-regulate apoptosis induction and the generation of reactive oxygen species (ROS) induced by 200µM H2O2 in SH-SY5Y cells. Moreover, EcI increased the activities of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxides (GSH-Px), reduced the levels of malondialdehyde (MDA) to restore the antioxidant defense system, and activated the nuclear factor E2-related factor (Nrf2)/heme oxygenase 1 (HO-1) pathway to combat oxidative stress. In addition, EcI also promoted autophagy during this process. Interestingly, the protective effect was remarkably reversed by autophagy inhibitors, bafilomycin A1 (Baf) or 3-Methyladenine (3-MA). These results demonstrate that autophagy is contribute to the protective effect of EcI. Collectively, our findings provide a new insight into the potential protective effect of EcI by focusing on the role of autophagy.