Warnerburnham1144

The sulfate radical based advanced oxidation processes (SR-AOPs) has shown great potential in environmental remediation. In recent years, metal-free catalysts have attracted great attention due to their properties of low environmental risk and high catalytic activity. Among them, biochar-based catalysts are widely studied for their low cost by using substance existing in nature as raw material. DT2216 mw In this work, egg shell derived biochar (ES-biochar), which was prepared by a simple one-pot pyrolysis method, has been proven to be an effective and innovative catalyst to activate persulfate for aqueous organic pollutant degradation. In addition, ES-biochar showed superior performance in the degradation reaction with removal efficiency of more than 90% in 120 min for 2,4-dichlorophenol (2,4-DCP), which was selected as a representative organic pollutant. Further quenching tests and electron spin resonance spectroscopy demonstrated that both free-radicals and non-radicals pathways were involved in this process, and OH dominated in free-radicals process. More importantly, this work not only proposed a novel biochar material as an efficient persulfate activator, but also provided a value-added reuse approach for egg shell in line with the concept of resource recycling and environmental sustainability.Plant seedlings are susceptible to copper (Cu) toxicity. As copper levels in soil continue to rise with the use of Cu-based agrochemicals, alleviation of Cu stress is of paramount importance. Traditional approaches to allay Cu stress are well documented but are typically found to be either costly or inefficient. Given their small size, ionic character, and high biocompatibility, specific polymeric nanoparticles (NPs) may have the potential for mitigating metal toxicity to crops. In this pioneering study, we investigated the effects of newly synthesized polysuccinimide NPs (PSI-NPs) on corn (Zea mays L.) seed germination and seedling growth under different levels of Cu stress. The results showed that PSI-NPs influenced seed germination in a dose-dependent manner with an optimal rate of 200 mg L-1. In addition, the positive effects of PSI-NPs on seed germination indexes were found to be positively correlated with enhanced seed imbibition (r = 0.82). The addition of PSI-NPs significantly mitigated Cu stress as indicated by improved growth of shoots and roots, and higher antioxidant enzyme activity observed with co-exposure to PSI-NPs as compared to Cu stress treatment only. Cu concentrations in seedling root and shoot significantly increased with increasing Cu treatment rate. Higher uptake of Cu by plant was observed in the Cu-PSI-NPs co-treatment than single Cu treatment. The alleviation effect of PSI-NPs could be explained by the enhanced antioxidant enzyme activities and storage of Cu as Cu-PSI complexes in plants with reduced phytotoxicity. These findings will open the opportunity of using PSI-NPs as a regulator to enhance seed germination and improve seedling growth under stress of heavy metals like Cu.Hypoxia and acidification in coastal waters are of global concern. However, the complex hydrodynamic processes and human interferences are major challenges for the diagnosis of their mechanism. The role of seasonal water masses involved still remains unknown. We herein investigated the dynamics of dissolved oxygen (DO), pH, inorganic and organic nutrients in the South Yellow Sea (SYS) in autumn, aiming for a better understanding of the biogeochemical processes of the Yellow Sea Cold Water (YSCW). Low DO, pH and organic nutrients were observed in the YSCW, while the apparent oxygen utilization and dissolved inorganic nutrients were relatively high. Quantitative assessment shows that although the water volume of the YSCW accounts for only 16.4% that of the SYS, the reservoirs of dissolved inorganic nitrogen, phosphate and silicate were 30.8%, 52.1% and 33.0%, respectively. Our results suggest that organic matter mineralization and water stratification are important driving forces for hypoxia, acidification and nutrient accumulation in the YSCW. The upwelling of the YSCW can bring abundant nutrients and stimulate the algal blooms, which are detrimental to the ecology. As global warming continues, the hypoxia and acidification in the YSCW will likely intensify in the near future in response to a projected slowdown of overturning circulation.A bioaugmentation approach was used to enhance the performance of anaerobic digestion (AD) using cow manure (CM) as the substrate in a continuous system. To obtain the desirable microbial culture for bioaugmentation, a biochemical methane potential test (BMP) was used to evaluate three commonly used inocula namely (1) municipal solid waste (MSW), (2) wastewater treatment plant (WWTP), and (3) cow manure digester (CMMD) for their hydrolytic capacity. The highest lignocellulose removal (56% for cellulose and 50% for hemicellulose) and the most profusion of cellulolytic bacteria were obtained when CM was inoculated with CMMD. CMMD was thus used as the seed inoculum in a continuously operated reactor (Ra) with the fiber fraction of CM as the substrate to further enrich cellulolytic microbes. After 100 days (HRT 30 days), the Bacteria fraction mainly contained Ruminofilibacter, norank_o_SBR1031, Treponema, Acetivibrio. Surprisingly, the Archaea fraction contained 97% 'cellulolytic archaea' norank_c_Bathyarchaeia (Phylum Bathyarchaeota). This enriched consortium was used in the bioaugmentation experiment. A positive effect of bioaugmentation was verified, with a substantial daily methane yield (DMY) enhancement (24.3%) obtained in the bioaugmented reactor (Rb) (179 mL CH4/gVS/d) than that of the control reactor (Rc) (144 mL CH4/gVS/d) (P less then 0.05). Meanwhile, the effluent of Rb enjoyed an improved cellulose reduction (14.7%) than that of Rc, whereas the amount of hemicellulose remained similar in both reactors' effluent. When bioaugmentation stopped, its influence on the hydrolysis and methanogenesis sustained, reflected by an improved DMY (160 mL CH4/gVS/d) and lower cellulose content (53 mg/g TS) in Rb than those in Rc (DMY 144 mL/CH4/gVS/d and cellulose content 63 mg/g TS, respectively). The increased DMY of the continuous reactor seeded with a specifically enriched consortium able to degrade the fiber fraction in CM shows the feasibility of applying bioaugmentation in AD of CM.