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We develop a transmission planning framework for coupled natural gas and electric power systems facing geographically correlated failures. The framework uses a stochastic optimization method incorporating uncertainty in the locations of the geographically correlated failures. We compare the proposed planning framework with the traditional N-k method which plans for geographically uncorrelated failures in terms of improving resilience effectively against geographically correlated failures. The proposed planning framework is illustrated using a small test system, but is scalable to larger system sizes and portable to other coupled-infrastructure contexts. We illustrate how planning for geographically correlated failures can enhance system-wide robustness by reinforcing the network connectivity between supply and demand locations instead of addressing local vulnerability at specific locations when planning for geographically uncorrelated failures. Planning for geographically correlated failures improves system resilience to both geographically correlated and uncorrelated failures significantly, but the converse is not true in our case study. • Propose a planning method for coupled systems with spatially correlated failures. • Planning for correlated failures enhances network connectivity and resilience. • Planning for uncorrelated failures addresses more local vulnerabilities. [ABSTRACT FROM AUTHOR]

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]

Formaldehyde (HCHO) is a toxic and hazardous air pollutant that widely exists in atmosphere. Insufficient spatial and temporal coverage of surface HCHO measurements is limiting studies on surface HCHO-related air quality management and health risk assessment. This study develops a method to derive global ground-level HCHO concentrations from satellite-based tropospheric HCHO columns using TM5-simulated surface-to-column conversion factor with coarse spatial resolution. The method improves the factor more representative in finer grids by constraining TM5-simulated vertical profile shapes with satellite HCHO columns. The surface HCHO concentrations derived by the Ozone Mapping and Profiler Suite (OMPS) show good correlation with in situ HCHO measurements (R = 0.59) from the U.S. Environmental Protection Agency surface network. We investigated how surface HCHO relates to urbanization and population aggregation over seven regions with high HCHO pollution. The results show urban HCHO increases as a power function with population size in China, India, and West Asia. HCHO concentrations in rural aeras also present strong log–log relationship with population aggregation in China, India, the United States, and Europe. Moreover, OMPS-derived ground-level HCHO concentrations were used to estimate global cancer burden caused by long-term outdoor HCHO exposure. The results show that up to 418188 more people worldwide will develop this cancer during the human life cycle. The global cancer burden is mainly from the South-East Asia region (33.11 %) and the Western Pacific region (22.95 %). This cancer occurrence in India and China is ranked 1st and 2nd in the world due to the large population size and serious HCHO pollution. Besides, global surface HCHO concentrations and cancer burden derived from the Environmental Trace Gases Monitoring Instrument which is China's first hyperspectral space-based spectrometer are found similar patterns with that from OMPS. Our results provide new insight into the impact of population urbanization on HCHO pollution and global outdoor HCHO-caused health risks. [ABSTRACT FROM AUTHOR]

Satellite remote sensing is an important technique providing long-term and large-scale information of formaldehyde (HCHO), which plays a crucial role in atmospheric chemistry. Low signal-to-noise ratio and poor stability of the Environmental Trace Gases Monitoring Instrument (EMI) On board Gaofen-5 satellite, the first Chinese space-borne spectrometer, make HCHO retrieval extremely difficult. Here we firstly retrieved HCHO vertical column densities (VCDs) from EMI through in-flight spectral calibration, retrieval setting optimization and stripe correction. Retrieved EMI HCHO VCDs correlate well with those measured by Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) with normalize mean bias (NMB) below 25%. EMI HCHO VCDs are comparable with those observed by Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI). This study reveals that HCHO can be observed successfully by algorithm optimization despite of poor performance of space-borne spectrometer. The retrieved EMI HCHO VCDs are applied to locate emission sources of volatile organic compounds (VOCs). • First retrieval of HCHO from Environmental Trace Gases Monitoring Instrument (EMI). • Algorithm optimization is proposed suitable for EMI HCHO retrieval. • HCHO vertical column density (VCD) correlates well with ground-based measurements. • EMI HCHO measurements are improved to a comparable level with OMI measurements. • HCHO hotspots and source of volatile organic compounds are captured successfully by EMI. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are key precursors of PM 2.5 and ozone. Glyoxal can be utilized as an indicator of VOC emission sources and secondary organic aerosol (SOA) formation. In this study, the high-resolution satellite observations of glyoxal were utilized to identify anthropogenic VOC sources, which can be utilized to formulate pollution control policies. Glyoxal vertical column densities were firstly retrieved by the TROPOspheric monitoring instrument (TROPOMI) onboard the Copernicus Sentinel-5 Precursor satellite. Glyoxal retrieval is sensitive to wavelength; therefore, four different areas were studied, and the optimum wavelength range of 435–462 nm was determined and applied in the wavelength sensitivity test. Glyoxal slant column density was corrected by utilizing the daily stripe-correction in the Sahara region which reduces the error by approximately 2.2 × 1014 molec/cm2. Glyoxal vertical column densities computed using TROPOMI were validated via multi-axis differential optical absorption spectroscopy measurements obtained at three sites; the daily normalized mean bias and standard deviation for the three sites were -27.5 % ± 6.5%, 1.8% ± 7.5%, and −6.6 % ± 17.3%, respectively. Monthly averaged data shows good correlation with Pearson correlation coefficients (R) of 0.90, 0.78 and 0.92, at three MAX-DOSA sites, respectively. The global spatial distribution of glyoxal showed large areas of high-concentration glyoxal distributed over tropical rainforests near the equator, which were attributed to biomass combustion and biogenic processes. Numerous urban hotspots were identified to be mainly concentrated in developing countries, especially those in East Asia and the Middle East. The highest glyoxal vertical column densities were observed over eastern China, and the high-glyoxal concentration areas were mainly located over urban and industrial areas, indicating a significant anthropogenic glyoxal source. Kilometer-level TROPOMI can identify factory emission sources that are undetectable by Ozone Monitoring Instrument due to the higher resolution of TROPOMI. • Realizing the global kilometer-level glyoxal observation for the first time. • Indicating of volatile organic compounds emission sources and secondary organic aerosol formation. • Utilizing glyoxal results to realize identification of factory sources. [ABSTRACT FROM AUTHOR]

To prevent the spread of the COVID-19 epidemic, the Chinese megacity Wuhan has taken emergent lockdown measures starting on January 23, 2020. This provided a natural experiment to investigate the response of air quality to such emission reductions. Here, we decoupled the influence of meteorological and non-meteorological factors on main air pollutants using generalized additive models (GAMs), driven by data from the China National Environmental Monitoring Center (CNEMC) network. During the lockdown period (Jan. 23 – Apr. 8, 2020), PM 2.5 , PM 10 , NO 2 , SO 2 , and CO concentrations decreased significantly by 45 %, 49 %, 56 %, 39 %, and 18 % compared with the corresponding period in 2015–2019, with contributions by S(meteos) of 15 %, 17 %, 13 %, 10 %, and 6 %. This indicates an emission reduction of NO x at least 43 %. However, O 3 increased by 43 % with a contribution by S(meteos) of 6 %. In spite of the reduced volatile organic compound (VOC) emissions by 30 % during the strict lockdown period (Jan. 23 – Feb. 14, 2020), which likely reduced the production of O 3 , O 3 concentrations increased due to a weakening of the titration effect of NO. Our results suggest that conventional emission reduction (NO x reduction only) measures may not be sufficient to reduce (or even lead to an increase of) surface O 3 concentrations, even if reaching the limit, and VOC-specific measures should also be taken. [Display omitted] • COVID-19 lockdown caused a significant reduction in pollutant, except ozone. • GAMs model can explain nonlinear relationship between pollutants and meteorology. • Increasing of ozone mainly due to weakening of titration effect. • Ozone pollution needs to be controlled by a variety of pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] This research aimed to overcome the current challenges in the application of natural carotenoid antioxidants, such as their complex preparation processes, low bioavailability and poor drug stability. Herein, a mechanochemical method was used to prepare an inclusion complex (IC) that self-assembles into micelles in aqueous solution and achieves solid-phase loading of astaxanthin (AST). The NMR analysis, thermodynamics study, particle size analysis and electron microscopy image results showed that AST, hydroxypropyl β-cyclodextrin (HPβ-CD) and glyceryl monostearate (GMS) formed self-assembled micelles and maintained good stability in aqueous solution. The antioxidant performance experiments showed that the formation of IC increases free radical scavenging activity. The pharmacokinetic studies showed that the bioavailability of the astaxanthin inclusion complex increased 4-fold. The tissue distribution experiments showed that the astaxanthin inclusion complex targets the liver to exert its antioxidant effects. The proposed method uses an innovative preparation technology to produce an efficient drug delivery system without solvents, and it exerts powerful antioxidant activity against astaxanthin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calculate ecological quality using the Ensemble Learning method. • Gridding the regional space and proposing an Ecological Information State Layer (EISL). • Semi-supervised learning has better portability in ecological computing. • Analyze the weight of ecological factor characteristics to provide recommendations for ecological conservation. Habitat quality is an indicator of the ecological evolution of a region, and evaluating habitat quality utilizing Machine Learning approaches can reflect the ecological status of a region more objectively. Gridded statistical ecological factors in the study region were utilized to build the Ecological Information State Layer (EISL) in the grid space. Calculate the Environmental Quality Index (EQI) of the sampled grid to evaluate the performance index of the models on the sampled grid. The model with the optimal performance index is selected for the task of habitat quality classification in the research region, and then especially decision-making advice is offered by inverting the degree of influence of ecological elements on habitat quality. The results show that: (1) The Semi-supervised Ensemble Learning model (Tri-training) Accuracy, Kappa coefficient, and F1-score are 0.93, 0.89, and 0.92, respectively, as the optimal model for the habitat quality classification task. (2) Based on the results of the ecological categories calculation, the current ecosystem quality of the southwestern section of the Daxia River Basin is maintained as a positive indicator. the ecosystem quality inside the living space centered on the cities of Linxia and Hezuo shows negative indicator changes. (3) The calculation results of the inverse importance of ecological factors show that vegetation index and human population density are the key factors impacting the habitat quality of the Daxia River Basin. In the ecological management of Daxia River Basin, the degree of spatial aggregation of people's settlements should be reduced while preserving and expanding vegetation cover. Using Tri-training's comprehensive analysis of multiple ecological factors, regional habitat quality can be accurately assessed. [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]