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In this study, a moderate method for efficient zero-waste utilization and reforming from shrimp shell waste was developed by means of mechanochemistry. The method enables the conversion of shrimp shell waste into astaxanthin, chitin, small peptides, amino acids, and lipids for zero waste; the method uses green mechano-enzymatic hydrolysis and mechanical solid organic acid treatment of shrimp shell waste to achieve zero consumption of strong acids alkali, and organic solvent. The underlying mechanism was revealed by thermodynamic determination, spectroscopic analysis, and electron microscopy observation of the extraction process. In the research, a green economic reuse approach for crustacean waste is proposed to achieve United Nations Sustainable Development Goals 3, 6, 12 and 14 with the concept of circular economy(Sutherland et al., 2021), and this study proposes a green economic reuse method of crustacean waste. [Display omitted] • A moderate method for efficient zero-waste utilization and reforming from shrimp shell waste. • The method to achieve zero consumption of strong acids, alkali and organic solvent. • The method is low-energy input and mild conditions. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide (NO 2) in the lower marine atmosphere, mainly emitted by maritime shipping, plays a crucial role in air pollution formation and global human health. However, few measurements of marine atmospheric NO 2 hinder knowledge of trace gas trends and atmospheric chemistry evolution due to shipping emissions. In this study, we use long-term satellite observations of tropospheric NO 2 column from the European TROPOspheric Monitoring Instrument (TROPOMI) and the Chinese Environmental trace gases Monitoring Instrument (EMI) to analyze marine atmospheric NO 2 variations, especially during the global COVID-19 pandemic and escalating geopolitical crises. First, we demonstrate the detection of NO 2 enhancements along shipping routes, including the North Atlantic route, the North Pacific route, and the Cape route, indicating significant emissions of atmospheric NO 2 from on-ocean shipping. Second, we observe and quantify the response of marine atmospheric NO 2 concentrations to major shipping events, such as the Suez Canal blockage, the Los Angeles-Long Beach port congestion, and the Russia-Ukraine war, resulting in local NO 2 concentration variations of approximately 40% decrease to 70% increase. Long-term analysis reveals reduced NO 2 concentrations in most coastal ports and maritime shipping routes during the COVID-19 lockdown, with reductions exceeding 50% or durations lasting up to 200 days. However, some rapidly developing ports, such as Beibu Gulf (China) and Dakar (Senegal), did not experience a decrease in NO 2 concentrations, suggesting that local authorities need to pay more attention to these fast-growing yet underestimated emission sources. In addition, by excluding the impact of meteorology using statistical models, we find that the current Emission Control Area (ECA) policies have effectively reduced NO 2 concentrations in Chinese coastal ports. These results contribute to understanding spatiotemporal characteristics of marine atmospheric NO 2 , including ports and open-sea shipping routes, and guide further ECA policies to control marine NO 2 pollution. • New-generation satellites including TROPOMI and EMI can detect enhanced NO 2 pollution over maritime shipping routes. • Major shipping events have led to from −40% to 70% variations in local marine atmospheric NO 2 concentrations. • The COVID-19 pandemic reduced NO 2 pollution by > 50%, for a maximum of 200 days in the world's top ports. • Shipping emission control policies have effectively improved NO 2 pollution in Chinese ports since January 2019. [ABSTRACT FROM AUTHOR]