A MIKE SHE hydrological-solute transport model including nitrate reduction is employed to evaluate the delayed response in nitrogen loads in catchment streams following the implementation of nitrogen mitigation measures since the 1980s. The nitrate transport lag times between the root zone and the streams for the period 1950-2011 were simulated for two catchments in Denmark and compared with observational data. Results include nitrogen concentration and mass discharge to streams. By automated baseflow separation, stream discharge was separated into baseflow and drain flow components, and the nitrogen concentration and mass discharge in baseflow and drain flow were determined. This provided insight on the development of stream nitrogen loads, with a short average lag time in drain flow and a long average lag time in baseflow. The long term effect of nitrogen mitigation measures was determined, with results showing that there is a 15 years long delay in the appearance of peak nitrogen loads in streams. This means that real time stream monitoring data cannot be used alone to assess the effect of nitrogen mitigation measures.
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http://dx.doi.org/10.1016/j.scitotenv.2018.01.255 | DOI Listing |
J Environ Manage
January 2025
School of Artificial Intelligence, Xidian University, No. 2 South Taibai Road, Xi'an, Shaanxi, 710071, China.
In the process of partial nitrification and anaerobic ammonia oxidation (anammox) for nitrogen removal, the process offers simple metabolic pathways, low operating costs, and high nitrogenous loading rates. However, since the partial nitrification-anammox (PN-anammox) process combines partial nitrification and anammox reactions within the same reactor, strict control of dissolved oxygen (DO) is essential. Additionally, assessing treatment performance through chemical measurement involves time lag, making it challenging to recover the biological process when issue arise, especially in the PN-anammox process, where strict DO control and the sensitivity of anammox bacteria to conditions and substrates demand timely intervention.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Collaborative Innovation Center of Sustainable Energy Materials, School of Physical Science and Technology, Guangxi University, Guangxi Key Laboratory of Electrochemical Energy Materials, State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, Nanning 530004, China. Electronic address:
Transition metal-nitrogen-carbon (MNC) based on 3d metal atoms as promising non-precious metal catalysts have been extensively exploited for oxygen reduction reaction (ORR), but MNC with 4f rare earth metals have been largely ignored, most likely due to their large atomic radii that are difficult to coordinate with N dopants using conventional precursors. Herein, atomically dispersed dysprosium-nitrogen-carbon (DyNC) nanosheets were developed via the pyrolysis of anitrogen-containing chelate compound of 2, 4, 6-Tri (2-pyridyl) 1, 3, 5-triazine (TPTZ) ligand with Dy under the assistance of molten NaCl. The as-synthesized DyNC features specific moieties of single Dy atom coordinated by N and O as active sites for ORR, displaying excellent performance.
View Article and Find Full Text PDFWaste Manag
January 2025
School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, China. Electronic address:
Owing to the massive refractory lignocellulose and leachate-organic loads, the stabilization of municipal solid waste (MSW) landfill is often prolonged, resulting in environmental burdens. Herein, various assembled multifunctional microbial inoculums (MMIs) were introduced into the semi-aerobic bioreactor landfill (SABL) to investigate the bioaugmentation impacts. Compared to control (CK) and other MMIs treatments (G1-G3), LD + LT + DM inoculation (G4) significantly increased volatile solids degradation (9.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Normal University, Jinan 250014, P. R. China.
Herein, we report a nanoscale composite COF material loaded with copper peroxide (CuO) and nitric oxide (NO) prodrug a stepwise post-synthetic modification. The obtained CuO2@COF-SNO can undergo a cascade reaction in the tumor microenvironment to generate reactive oxygen and nitrogen species (ROS/RNS) to enhance chemodynamic therapy of the tumor.
View Article and Find Full Text PDFJ Biomater Appl
January 2025
Biomedical Engineering Graduate Program, Toronto Metropolitan University, Toronto, ON, Canada.
This study explores mesoporous bioactive glasses (MBGs) that show promise as advanced therapeutic delivery platforms owing to their tailorable porous properties enabling enhanced drug loading capacity and biomimetic chemistry for localized, sustained release. This work systematically investigates the complex relationship between MBG composition and surfactant templating on structural evolution, bioactive response, resultant drug loading efficiency and release. A total of 12 samples of sol-gel-derived MBG were synthesized using cationic and non-ionic structure-directing agents (cetyltrimethylammonium bromide, Pluronic F127 and P123) while modulating the SiO/CaO content, generating MBG with surface areas of 60-695 m/g.
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