The study evaluated influences of sludge concentration, temperature and solids retention time (SRT) for the hydrolysis of waste activated sludge (WAS) in anaerobic digesters. The results indicated that volatile fatty acids (VFA) production increased when the concentration of mixed liquor volatile suspended solids (MLVSS) was higher. When SRT was 48 h, VFA concentration increased 8.43 times from 4.57 to 23.78 gMLVSS/L. VFA generation was significantly affected with different temperature and SRT. When the temperature changed from 40 to 50°C, it induced 1.65-fold increase in VFA yield. The optimal SRT was 48 h. As VFA concentration decreased only 1.31 times compared with maximum VFA production at SRT of 120 h. Iso-valeric acid, acetic acid and n-butyric acid were the dominant VFA produced and would improve ployhydroxyvalerate proportion in polymer. The feasibility of nitrogen and phosphorus recovery and the risk of metal ion released depended on the nature of WAS.
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http://dx.doi.org/10.1016/j.biortech.2012.05.126 | DOI Listing |
PLoS One
January 2025
Chemical & Petroleum Engineering Department, United Arab Emirates University, Al Ain, United Arab Emirates.
Oil fields located in cold environments and deep-sea locations often face challenges with paraffin wax buildup in pipelines during long-distance crude oil transportation. Various strategies have been employed to address this issue, with chemical methods being the most effective and economical. However, traditional chemical inhibitors present problems due to their high toxicity and low biodegradability, leading to increased operational costs and environmental concerns.
View Article and Find Full Text PDFEnviron Toxicol Chem
January 2025
Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, One Shields Avenue, Davis, Yolo County, CA, 95616USA.
Juvenile Chinook Salmon (Oncorhynchus tshawytscha) populations have decreased substantially in the Sacramento-San Joaquin Delta (Delta) over the past decades, so considerably that two of the four genetically distinct runs are now listed in the Endangered Species Act. One factor responsible for this decline is the presence of contaminants in the Delta. Insecticides, used globally in agricultural, industrial, and household settings, have the potential to contaminate nearby aquatic systems through spray drift, runoff, and direct wastewater discharge.
View Article and Find Full Text PDFMed Phys
January 2025
OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.
Background: Previous studies have shown that in-beam magnetic resonance imaging (MRI) can be used to visualize a proton beam during the irradiation of liquid-filled phantoms. The beam energy- and current-dependent local image contrast observed in water was identified to be predominantly caused by beam-induced buoyant convection and associated flow effects. Besides this flow dependency, the MR signal change was found to be characterized by a change in the relaxation time of water, hinting at a radiochemical contribution, which was hypothesized to lie in oxygen depletion-evoked relaxation time lengthening.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, 208016, India.
The atmospheric dicarboxylic acids (DCAs) have a significant impact on the climate and indirectly affect human health, making them important organic substances. PM bound DCAs were analysed for Jorhat, India, 2019. In addition to the temporal variability, seasonal variation throughout the year and the impact of varying meteorological factors on DCAs concentration have also been studied.
View Article and Find Full Text PDFNanomicro Lett
January 2025
Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Fudan University, Shanghai, 200433, People's Republic of China.
Practical Zn metal batteries have been hindered by several challenges, including Zn dendrite growth, undesirable side reactions, and unstable electrode/electrolyte interface. These issues are particularly more serious in low-concentration electrolytes. Herein, we design a Zn salt-mediated electrolyte with in situ ring-opening polymerization of the small molecule organic solvent.
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