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Understanding the CO2 emission characteristics and key mitigation pathways of intercity passenger transport is crucial for achieving sustainable development in the transport system. Using origin-destination data on travel between city pairs by various transportation modes, we employ the life cycle assessment (LCA) method to estimate route-level CO2 emissions from intercity multimodal passenger transport corridors, considering infrastructure construction and vehicle operation phases. Subsequently, a sensitivity analysis is conducted to assess the impact of 39 parameters associated with the construction phase, operation phase, and transportation modes on CO2 emissions from corridors. Trend analysis is employed to explore the future emission mitigation potential for the parameters that have the most significant impact on corridor emissions. Four intercity multimodal passenger corridors in China are selected as case studies. Results indicate that the CO2 emissions per passenger-kilometer from these corridors exhibit an approximate negative linear relationship with corridor lengths. The proportion of construction-related CO2 emission intensity of various intercity passenger transport modes varies significantly, ranging from 2.5 to 32.9%. In the medium term, effective emission-mitigation strategies should focus on decreasing private car gasoline consumption in three corridors under 200 km in length, as well as decreasing private car gasoline consumption and promoting clean electricity in the Xi'an-Yan'an corridor. In the long term, efforts should be placed on increasing electric private car share and promoting clean electricity. This study lays a crucial foundation for the refined management of CO2 emissions from future intercity passenger transport.

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Determining the contaminants reduction rate by dissolved ferrous iron (Fe(II)aq) bound to iron oxides is curial for evaluating the abiotic attenuation of contaminants in aquifers. However, few studies have assessed the contaminants reduction rate controlled by thermodynamic parameters in heterogeneous systems with different iron oxides. In this study, a linear free energy relationship (LFER) was established between the nitrobenzene reduction rate and the thermodynamic driving force (reduction potential (EH) and pH) in Fe(II)aq-goethite-hematite co-existing systems. Results showed that the reduction rate of nitrobenzene correlated with the EH of the heterogeneous system. The standard reduction potential (EH0mix) of the mixed iron oxides could be obtained by a proportionate linear combination of the single iron oxide system EH0. Based on this, the EH of the heterogeneous systems could be calculated theoretically by combining EH0mix and the Nernst equation. Furthermore, a parallel LFER with the slope of 1 was established to associate the nitrobenzene reduction rate with EH and pH. The intercept term was related to the adsorption capacity of different iron oxides towards Fe(II)aq. The Fe(II)aq saturation adsorption capacity of hematite was 1.5 times higher than that of goethite. After normalizing the nitrobenzene reduction rate to the Fe(II)aq saturation adsorption capacity, the maximum difference in intercept terms was reduced from 37% to 15%. These findings would provide an important and feasible methodological support for the quantitative evaluation of abiotic attenuation of contaminants in groundwater.

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China's rapid expansion of civil aviation has led to an increase in pollution-related issues, causing adverse health effects on populations near airports and downwind. Accurately quantifying aviation emissions is essential for effective emission management. Here, we developed a high-resolution aviation emissions inventory for China by employing a bottom-up approach that relied on daily flight schedules. By using the Aeronautical Information Publication (AIP) to reproduce real-world flight routes rather than conventional great-circle routes, we improved the accuracy of emissions and investigated the potential for reducing these emissions. Our findings demonstrated substantial variations in domestic civil aviation emissions both spatially and temporally. Emissions peaked in most provinces during Chinese holidays, particularly the Chinese Lunar New Year and summer holidays, highlighting the importance of detailed activity data for accurate emissions calculations. Therefore, we recommend extensive utilization of real-world flight routes, particularly in areas with limited Automatic Dependent Surveillance-Broadcast (ADS-B) coverage since they provide more accurate representations of actual flight trajectories. Our study also identified regions like Shaanxi, Sichuan, Beijing, and their surroundings having considerable potential for emission reduction due to substantial deviations from great-circle routes. This approach can enhance the accuracy and spatiotemporal resolution of aviation emissions at national and global scales throughout the year, without relying on extensive, long-term real-time flight trajectories. Additionally, it provides a unique way to quantify the potential for emission reductions across provinces in civil aviation, ultimately contributing to mitigating pollution-related health impacts from aviation emissions and promoting a more sustainable aviation industry.

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Coking industry is usually regarded as a high pollution and high energy consumption industry. China is accelerating its efforts to reduce pollution and carbon emissions in the industrial sector, which has received little attention as the world's largest producer of coke. Therefore, in this study, the trend of air pollution and carbon emissions in China's coking industry and the path of coordinated emission reduction were studied. The results indicate that the average annual emissions of PM, SO2, NOx, VOCs, and CO2 in China's coking industry from 2012 to 2022 amount to 205.98, 69.47, 193.45, 599.80 Gg and 191.10 Tg, respectively. The main sources of PM, SO2, NOx, VOCs and CO2 in coking industry were coal preparation (51.5 %), charge and pushing (39.5 %), coke oven gas (99.8 %), byproduct recovery (47.0 %) and fuel combustion (87.5 %). The emissions from coking plants in central and southern Shanxi, eastern and southern Hebei, and central Shandong are the most concentrated. Ultra-low emission transformation and deep treatment of VOCs have greatly reduced pollutant emissions in key areas of air pollutant control, but the actual emission reduction effect of these measures has been weakened by the additional emissions caused by the increase of coke production in other non-key areas. The research on synergetic emission reduction path shows that there is a great synergistic benefit between air pollutants and CO2 emission reduction in coking industry. It is estimated that the APeq (air pollutants and carbon equivalent) of China's coking industry in 2025, 2028 and 2030 will decrease by 38.2 %, 63.5 % and 70.8 % respectively compared with 2022. With the continuous promotion of pollution reduction and carbon reduction measures, the emission reduction potential of China's coking industry will gradually shift from key areas to non-key areas.

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Climate warming has become a global issue of close concern, and China, as a significant agricultural country, has an increasing demand for food, which requires China to increase carbon reduction in this industry. This paper accounts for carbon emissions from the food production industry (CEFI) using the input-output method, then screens the influencing factors of CEFI based on Random Forest (RF), analyzes the heterogeneous effects of the influencing factors on CEFI in different clusters through K-means-SHAP, and finally explores the potential of carbon emissions from this industry for the period 2024-2040. The study's findings are as follows: First, there are apparent inequalities in CEFI, especially between provinces, which are gradually increasing. Second, addressing people's consumption awareness and behaviors is not the fundamental solution to alleviate CEFI; instead, it should focus on sustainable agricultural production transformation and "food miles" in the transportation phase. In addition, attention needs to be paid to the impacts of fertilizer application, transport modes, and livestock management on the CEFI of each cluster. Finally, the study suggests that around 2028, 70% of China's provinces will be at the "carbon peak" and that less developed and more developed regions have more significant potential to reduce emissions. In this regard, this paper encourages a series of policies that are key to promoting the sustainable development of CEFI, such as reducing the volume and efficiency of traditional fertilizers, vigorously developing organic fertilizer inputs, strengthening technological innovation and R&D inputs in the transportation sector, and steadily supporting germplasm innovation in the livestock sector.

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Background: In the last few years, studies have initially confirmed the diagnostic significance of oxidation-reduction potential (ORP) in male infertility patients. In this article, we used meta-analysis to clarify the role of ORP in the diagnosis of male infertility. Methods: PubMed, Embase, Web of Science, and Cochrane Library were searched by computer for relevant published literature. Quality assessment of the included literature was performed by Quality Assessment of Diagnostic Accuracy Studies (QUADAS) scale. Heterogeneity analysis of included studies was conducted using Metadisc 1.4 and Stata 12.0, and effective models for quantitative synthesis were selected based on heterogeneity results; the sensitivity and specificity of the synthesis were obtained using the software, and in order to reduce the effects of heterogeneity and thresholds, the information of sensitivity and specificity was integrated. We used the subject receiver operating characteristic (SROC) curve, area under the curve (AUC) and Q* index for comprehensive evaluation. Results: Seven papers were eventually included in the study, and the results showed that ORP had a sensitivity of 0.81 [95% confidence interval (CI): 0.80-0.82] and specificity of 0.66 (95% CI: 0.63-0.69), an AUC of 0.8 and a Q* index of 0.74 for the diagnosis of male infertility. Conclusions: ORP has high sensitivity and specificity for diagnosing male infertility.

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This study develops environmentally benign capping technique to synthesize nanoparticles of Curcuma longa-coated titanium dioxide (CR-TiO2) from titanium isopropoxide by utilizing the extract of Rosa rubiginosa flowers as reducing and chelating agent. The biogenically synthesized nanoparticles revealed excellent anti-bacterial, electrochemical, and photocatalytic properties due to the presence of porous TiO2 nanostructures. The sharp peaks by XRD pattern showed the crystallinity and phase purity of TiO2 nanoparticles. BET analysis proved mesoporous nature of the materials with specific surface area of 134 m2 g -1. The vibrational spectra suggest hydroxyl groups from flavonoids of Curcuma longa acting as functionalizing agent for TiO2 nanoporous structures with visible luminescence, which is proven in fluorescence spectra and is applicable for photocatalytic studies. The anti-bacterial studies showed good inference on TiO2 nanoparticles against Pseudomonas auruginosa and proved it to be an excellent antipseudomonal agent with the oxidative potential. The maximum degradation of phenol red dye in the presence of TiO2 under visible light conditions was observed. The supercapacitor fabricated using the biogenic TiO2 three-electrode system exhibited a specific capacitance of 128 Fg-1 (10 mV s-1), suggesting it as an excellent electrode material. The LSV curve at 50 mV s-1 scan rate showed that oxygen reduction potential (ORR) of CR-TiO2 electrodes was 121 mV. The present study is a new application of nanoparticles in sustainability consideration of the environment as well as a solution to the power crisis with fewer limitations. The well-distinguished antidiabetic and BSA denaturation potential suggests that these porous TiO2 nanostructures can be useful for drug delivery as glucose inhibitors and oral anti-inflammatory drugs with the restriction of adverse side effects.

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Road transport is the primary source of greenhouse gas emissions in China's transportation field. As an important means to achieve the "double carbon" goal in the transportation field, the new energy automobile industry will face a large number of power battery scrapping in the future. In order to quantitatively assess the carbon emission reduction benefits generated by the spent ternary lithium-ion battery waste recycling industry, the carbon footprint accounting model of spent ternary lithium-ion battery waste recycling and utilization was constructed from the life cycle perspective. By optimizing the power structure and transportation structure, the carbon emission reduction potential of spent ternary lithium-ion battery waste recycling was predicted and evaluated. In addition, the uncertainty analysis was conducted using the propagation of uncertainty equation to ensure the reliability and effectiveness of the carbon footprint results. The results showed that the current carbon footprint of Chinese enterprises using wet technology to recover 1 kg waste lithium batteries was -2 760.90 g (directional recycling process) and -3 752.78 g (recycling process), and the uncertainty of the carbon footprint was 16 % (directional recycling process) and 15 % (recycling process), respectively. From the analysis of carbon emission contribution, the regenerated product stage was the primary source of carbon reduction in the wet recycling and utilization of waste ternary lithium batteries, whereas the battery acquisition, disassembly, and end treatment stages were the main sources of carbon increase. Compared to optimizing the transportation structure, optimizing the power structure could effectively achieve greater carbon emission reduction potential. Under the collaborative optimization scenario, compared to that before optimization, 14 %-19 % carbon emission reduction could be achieved. Compared with native products, the directional circulation process and recycling process could achieve 9 % and 11 % emission reduction potential, respectively.

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The study evaluated the effects of treating irrigation water with a coaxial flow variator (CFV) on the morpho-physiology of pot-cultivated test species, including cucumber (Cucumis sativus, CU), lettuce (Lactuca sativa, LE), and sorghum (Sorghum vulgare, SO), in early stages of growth. CFV caused a lower oxidation reduction potential (ORP), increased pH and flow resistance and inductance. It induced changes in the absorbance characteristics of water in specific spectral regions, likely associated with greater stretching and reduced bending vibrations compared to untreated water. While assimilation rate and photosynthetic efficiency were not significantly affected at 60 days after sowing, treated water increased the stomatal conductance to water vapour gsw (+79%) and the electron transport rate ETR (+10%) in CU, as well as the non-photochemical quenching NPQ (+33%) in SO. Treated water also reduced leaf temperature in all species (-0.86 °C on average). This translated into improved plant biomass (leaves: +34%; roots: +140%) and reduced leaf-to-root biomass ratio (-42%) in SO, allowing both faster aerial growth and soil colonization, which can be exploited to improve plant tolerance against abiotic stresses. In the C3 species CU and LE, plant biomass was instead reduced, although significantly in LE only, while the leaf-to-root biomass ratio was generally enhanced, a result likely profitable in the cultivation of leafy vegetables. This is a preliminary trial on the effects of functionalized water and much remains to be investigated in other physiological processes, plant species, and growth stages for the full exploitation of this water treatment in agronomy.

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Livestock and poultry products are an essential human food source. However, the rapid development of the livestock sector (LS) has caused it to become a significant source of greenhouse gas (GHG) emissions. Consequently, investigating the spatio-temporal characteristics and evolution of GHG emissions is crucial to facilitate the green development of the LS and achieve "peak carbon and carbon neutrality". This study combined life cycle assessment (LCA) with the IPCC Tier II method to construct a novel GHG emissions inventory. The GHG emissions of 31 provinces in China from 2000 to 2021 were calculated, and their spatio-temporal characteristics were revealed. Then, the stochastic impacts by regression on population, affluence, and technology (STIRPAT) model was used to identify the main driving factors of GHG emissions in six regions of China and explore the emission reduction potential. The results showed that GHG emissions increased and then decreased from 2000 to 2021, following a gradual and steady trend. The peak of 628.55 Mt CO2-eq was reached in 2006. The main GHG-producing segments were enteric fermentation, slaughtering and processing, and manure management, accounting for 45.39 %, 26.34 %, and 23.08 % of total GHG emissions, respectively. Overall, the center of gravity of GHG emissions in China migrated northward, with spatial aggregation observed since 2016. The high emission intensity regions were mainly located west of the "Hu Huanyong line". Economic efficiency and emissions intensity were the main drivers of GHG emissions. Under the baseline scenario, GHG emissions are not projected to peak until 2050. Therefore, urgent action is needed to promote the low-carbon green development of the LS in China. The results can serve as scientific references for the macro-prevention and control of GHG emissions, aiding strategic decision-making. Additionally, they can provide new ideas for GHG accounting in China and other countries around the world.

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Slow dissolution/hydrolysis of insoluble/macromolecular organics and poor sludge filterability restrict the application potential of anaerobic membrane bioreactor (AnMBR). Bubble-free membrane microaeration was firstly proposed to overcome these obstacles in this study. The batch anaerobic digestion tests feeding insoluble starch and soluble peptone with and without microaeration showed that microaeration led to a 65.7-144.8% increase in methane production and increased critical flux of microfiltration membrane via driving the formation of large sludge flocs and the resultant improvement of sludge settleability. The metagenomic and bioinformatic analyses showed that microaeration significantly enriched the functional genes and bacteria for polysaccharide and protein hydrolysis, microaeration showed little negative effects on the functional genes involved in anaerobic metabolisms, and substrate transfer from starch to peptone significantly affected the functional genes and microbial community. This study demonstrates the dual synergism of microaeration to enhance the dissolution/hydrolysis/acidification of insoluble/macromolecular organics and sludge filterability for AnMBR application.

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As an important precursor of secondary inorganic aerosols (SIAs), ammonia (NH3) plays a key role in fine particulate matter (PM2.5) formation. In order to investigate its impacts on haze formation in the North China Plain (NCP) during winter, NH3 concentrations were observed at a high-temporal resolution of 1 min by using the SP-DOAS in Tai'an from December 2021 to February 2022. During the observation period, the average NH3 concentration was 11.84 ± 5.9 ppbv, and it was determined as an ammonia-rich environment during different air quality conditions. Furthermore, the average concentrations of sulfate (SO42-), nitrate (NO3-) and ammonium (NH4+) were 9.54 ± 5.97 µg/m3, 19.09 ± 14.18 µg/m3 and 10.72 ± 6.53 µg/m3, respectively. Under the nitrate-dominated atmospheric environment, aerosol liquid water content (ALWC) was crucial for NH3 particle transformation during haze aggravation, and the gas-particle partitioning of ammonia played an important role in the SIAs formation. The reconstruction of the molecular composition further indicated that ammonium nitrate (NH4NO3) plays a dominant role in the increase of PM2.5 during haze events. Consequently, future efforts to mitigate fine particulate pollution in this region should focus on controlling NH4NO3 levels. In ammonia-rich environments, NO3- formation is more dependent on the concentration of nitric acid (HNO3). The sensitive analysis of TNO3 (HNO3 + NO3-) and NHX (NH3 + NH4+) reduction using the thermodynamic model suggested that the NO3- concentration decreases linearly with the reduction of TNO3. And the concentration of NO3- decreases rapidly only when NHX is reduced by 50-60 %. Reducing NOX emissions is the most effective way to alleviate nitrate pollution in this region.

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Hypoxia is a common phenomenon in solid tumors, and its presence inhibits the efficacy of tumor chemotherapy and radiotherapy. Accurate measurement of hypoxia before tumor treatment is essential. Three propylene amine oxime (PnAO) derivatives with different substituents attached to 2-nitroimidazole were synthesized in the work, they are 3,3,9,9-tetramethyl-1,11-bis(4-bromo-2-nitro-1H-imidazol-1-yl)-4,8-diazaundecane-2,10-dione dioxime (Br2P2), 3,3,9,9-tetramethyl-1,11-bis(4-methyl-2-nitro-1H-imidazol-1-yl)-4,8-diazaundecane-2,10-dione dioxime (Me2P2) and 3,3,9,9-tetramethyl-1,11-bis(4,5-dimethyl-2-nitro-1H-imidazol-1-yl)-4,8-diazaundecane-2,10-dione dioxime (2Me2P2). The three compounds were radiolabeled with 99mTc to give three complexes([99mTc]Tc-Br2P2, [99mTc]Tc-Me2P2 and [99mTc]Tc-2Me2P2) with good in vitro stability. [99mTc]Tc-Me2P2 with a more suitable reduction potential had the highest hypoxic cellular uptake, compared with [99mTc]Tc-2P2 that have been previously reported, [99mTc]Tc-Br2P2 and [99mTc]Tc-2Me2P2. Biodistribution results in S180 tumor-bearing mice demonstrated that [99mTc]Tc-Me2P2 had the highest tumor-to-muscle (T/M) ratio (12.37 ± 1.16) at 2 h in the four complexes. Autoradiography and immunohistochemical staining results revealed that [99mTc]Tc-Me2P2 specifically targeted tumor hypoxic regions. The SPECT/CT imaging results showed that [99mTc]Tc-Me2P2 could target the tumor site. [99mTc]Tc-Me2P2 may become a potential hypoxia imaging agent.

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Oxidation-reduction potential (ORP) is commonly used as a rapid measurement of the antimicrobial potential of free chlorine during industrial fresh produce washing. The current study tested the hypothesis that ORP can act as a "single variable" measurement of bacterial (vegetative and endospores) inactivation effectiveness with free chlorine irrespective of the water pH value. This situation has on occasion been assumed but never confirmed nor disproven. Chlorine-dosed pH 6.5 and 8.5 phosphate buffer solutions were inoculated with Escherichia coli (E. coli), Listeria innocua (L. innocua), or Bacillus subtilis (B. subtilis) endospores. ORP, free chlorine (FC), and log reduction were monitored after 5 s (for E. coli and L. innocua) and up to 30 min (for B. subtilis spores) of disinfection. Logistic and exponential models were developed to describe how bacteria reduction varied as a function of ORP at different pH levels. Validation tests were performed in phosphate buffered pH 6.5 and 8.5 cabbage wash water periodically dosed with FC, cabbage extract and a cocktail of Escherichia coli O157:H7 (E. coli O157:H7) and Listeria monocytogenes (L. monocytogenes). The built logistic and exponential models confirmed that at equal ORP values, the inactivation of the surrogate strains was not consistent across pH 6.5 and pH 8.5, with higher reductions at higher pH. This is the opposite of the well-known free chlorine-controlled bacterial inactivation, where the antibacterial effect is higher at lower pH. The validation test results indicated that in the cabbage wash water, the relationship between disinfection efficiency and ORP was consistent with the oxidant demand free systems. The study suggests that ORP cannot serve as a reliable single variable measurement to predict bacterial disinfection in buffered systems. When using ORP to monitor and control the antibacterial effectiveness of the chlorinated wash water, it is crucial to take into account (and control) the pH.

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Crop residues in agriculture pose disposal challenges and contribute to air pollution when burned. This study aims to use pigeonpea and maize stalks to produce biochar at different pyrolysis temperatures. Biochar can serve in carbon sequestration, as a soil amendment, and as an alternative fuel source. Pyrolysis was conducted at 400, 500, and 600 °C to examine the effects on physicochemical properties, fuel, and energy related properties. Increase in temperatures resulted in decrease of biochar yield, volatile matter, and O/C and H/C atomic ratios, while ash content and essential nutrients increased. Yield was observed to be higher in pigeonpea stalks derived biochar compared to maize stalks derived biochar at same pyrolysis temperatures. The yields of pigeonpea stalks derived biochar at 400 °C, 500 °C, and 600 °C are 34, 33 and 29%, respectively, and the yields of maize biomass-derived biochar at 400 °C, 500 °C, and 600 °C are 29, 28, and 26%, respectively. The organic carbon content is found to be higher in the biochar samples prepared at 600 °C, i.e., 10.44%, and 10.39% for pigeonpea and maize-derived biochar, respectively. The essential elements of biochar were increased with an increase in pyrolysis temperature except nitrogen which is conversely related to temperature. The biochar obtained through pyrolysis at 400 °C demonstrated superior characteristics compared to biochar produced at other temperatures. It exhibited a higher biochar yield, with approximately 84.60% for pigeonpea and 64.85% for maize fixed carbon content. Additionally, the energy retention efficiency was higher, reaching 67.33% for pigeonpea and 42.70% for maize-derived biochar at a pyrolysis temperature of 400 °C. The fixed carbon recovery efficiency was also notable at around 200.44% for PPS and 142.37% for maize biochar which is higher compared to biochar produced at other temperatures. Furthermore, the higher heating value (HHV) was approximately 30.75 MJ kg-1 for both the biochars, indicating their suitability as alternative solid fuels. A significant CO2 reduction potential of 84 CO2 eq kg-1 and 55 CO2 eq kg-1 was observed for pigeonpea and maize biochar, respectively. Hence, biochar is a promising and effective option for carbon sequestration, offering environmental benefits.

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The transition-metal free S-vinylation of thiophenols by vinylbenziodoxolones (VBX) constituted an important step forward in hypervalent iodine-mediated vinylations, highlighting the difference to vinyliodonium salts and that the reaction outcome was influenced by the substitution pattern of the benziodoxolone core. In this study, we report several new classes of hypervalent iodine vinylation reagents; vinylbenziodazolones, vinylbenziodoxolonimine and vinyliodoxathiole dioxides. Their synthesis, structural and electronic properties are described and correlated to the S-vinylation outcome, shedding light on some interesting facets of these reagents.

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Ferredoxins (Fds) are small proteins which shuttle electrons to pathways like biological nitrogen fixation. Physical properties tune the reactivity of Fds with different pathways, but knowledge on how these properties can be manipulated to engineer new electron transfer pathways is lacking. Recently, we showed that an evolved strain of Rhodopseudomonas palustris uses a new electron transfer pathway for nitrogen fixation. This pathway involves a variant of the primary Fd of nitrogen fixation in R. palustris, Fer1, in which threonine at position 11 is substituted for isoleucine (Fer1T11I). To understand why this substitution in Fer1 enables more efficient electron transfer, we used in vivo and in vitro methods to characterize Fer1 and Fer1T11I. Electrochemical characterization revealed both Fer1 and Fer1T11I have similar redox transitions (-480 mV and - 550 mV), indicating the reduction potential was unaffected despite the proximity of T11 to an iron­sulfur (FeS) cluster of Fer1. Additionally, disruption of hydrogen bonding around an FeS cluster in Fer1 by substituting threonine with alanine (T11A) or valine (T11V) did not increase nitrogenase activity, indicating that disruption of hydrogen bonding does not explain the difference in activity observed for Fer1T11I. Electron paramagnetic resonance spectroscopy studies revealed key differences in the electronic structure of Fer1 and Fer1T11I, which indicate changes to the high spin states and/or spin-spin coupling between the FeS clusters of Fer1. Our data implicates these electronic structure differences in facilitating electron flow and sets a foundation for further investigations to understand the connection between these properties and intermolecular electron transfer.

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A hypoxia occurred in eutrophic estuary was predicted using long short-term memory (LSTM) model with prediction time steps (PTSs) of 0, 1, 12, and 24 h. A capacitive potential (CP), which provides quantitative information on dissolved oxygen (DO) concentration, was used as a predictor along with precipitation, tide level, salinity, and water temperature. First, annual changes in DO concentration were clustered in three phases of annual DO trends (oversaturation, depletion, and stable) using k-means clustering. CP was the most influential variable in clustering the DO phases. The LSTM was implemented to predict the DO phases and hypoxia occurrences. In the simultaneous prediction of the depletion phase and hypoxia occurrence with a 12 h PTS, the accuracy was 92.1% using CP along with other variables; it was 3.3% higher than that achieved using variables other than CP. In the case of predicting the depletion phase and hypoxia non-occurrence using CP along with other variables, the accuracy was 61.1%, which was 5.5% higher than that when CP was not used. When using CP along with other variables, the total accuracy was highest for all PTS. Overall, the utilization of CP and machine learning techniques enables accurate predictions of both short-term and long-term hypoxia occurrences, providing us with the opportunity to proactively respond to disasters in aquaculture and environmental management due to hypoxia.

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Profound worldwide fleet electrification is thought to be the primary route for achieving the target of carbon neutrality. However, when and how electrification can help mitigate environmental impacts and carbon emissions in the transport sector remains unclear. Herein, the overall life-cycle environmental impacts and carbon saving range of two typical A-class vehicles in China, including electric vehicle (EV) and internal combustion engine vehicle (ICEV), were quantified by the life cycle assessment model for endpoint damage with localization parameters. The results showed that the EV outperformed the ICEV for the total environment impact after a travel distance of 39,153 km and for carbon emissions after 32,292 km. The ICEV was more carbon-friendly only when the driving distance was less than 3229 km/a. Considering a full lifespan travel distance of 150,000 km, the whole life-cycle average environmental impacts of EV and ICEV were calculated as 8.6 and 17.5 mPt/km, respectively, but the EV had 2.3 times higher impacts than the ICEV in the production phase. In addition, the EV unit carbon emission was 140 g/km, 46.8% lower than that of the ICEV. Finally, three potential reduction scenarios were considered: cleaner power mix, energy efficiency improvement and composite scenario. These scenarios contributed 19.1%, 13.0% and 32.1% reductions, respectively. However, achieving carbon peak and neutrality goals in China remains a great challenge unless fossil fuels are replaced by renewable energy. The research can provide scientific reference for the method and practice of emission reduction link identification, eco-driving choice and emission reduction path formulation.

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Manganese oxide (MnOx) is receiving increased interest in the nutrient removal of constructed wetlands (CWs); however, its service effectiveness for simultaneous greenhouse gas (GHG) emissions reduction is still vague. In this study, three vertical flow CWs, i.e., volcanics (CCW), manganese sand uniformly mixing with volcanics (Mn-CW) and MnOx doped volcanics (MnV-CW), were constructed to investigate the underlying mechanisms of MnOx on nutrient removal enhancement and greenhouse gas (GHG) emissions reduction. The results showed that the MnOx doped volcanics optimized the oxidation-reduction potential surrounding the substrate (-164.0 ∼ +141.1 mv), and resulted in the lowest GHG emissions (CO2-equivalent) from MnV-CW, 16.8-36.5 % lower than that of Mn-CW and CCW. This was mainly ascribed to mitigation of N2O produced during the NO3--N reduction process, according to results of 15N stable isotope labeling. Analysis of the microbial community structure revealed that due to the optimized redox conditions through chemical doping of MnOx on volcanics, the abundance of microbe involved in denitrification and Mn-oxidizing process in the MnV-CW was significantly increased at genus level, which led to a higher Mn cycling efficiency between biogenic MnOx and Mn2+, and enhanced denitrification efficiency and N2O emission reduction. This study would help to understand and provide a preferable reference for future applications for manganese-based CW.

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