Carbon Reduction and Pollutant Abatement by a Bio-Ecological Combined Process for Rural Sewage.

In order to explore the treatment effect of a bio-ecological combined process on pollution reduction and carbon abatement of rural domestic wastewater under seasonal changes, the rural area of Lingui District, Guilin City, Guangxi Province, China was selected to construct a combined process of regulating a pond, biological filter, subsurface flow constructed wetland, and ecological purification pond. The influent water, effluent water, and the characteristics of pollutant treatment in each unit were investigated. The results showed that the average removal rates of COD, TN, and NH3-N in summer were 87.57, 72.18, and 80.98%, respectively, while they were 77.46, 57.52, and 64.48% in winter. There were significant seasonal differences in wastewater treatment results in Guilin. Meanwhile, in view of the low carbon:nitrogen ratio in the influent and the poor decontamination effect, the method of adding additional carbon sources such as sludge fermentation and rice straw is proposed to strengthen resource utilization and achieve carbon reduction and emission reduction. The treatment effect of ecological units, especially constructed wetland units, had a high contribution rate of TN treatment, but it was greatly impacted by seasons. The analysis of the relative abundance of the microbial community at the phylum level in constructed wetlands revealed that Proteobacteria, Acidobacteria, Chloroflexi, Firmicutes, Bacteroidetes, Planctomycetota, and Actinobacteria were the dominant phyla. The relative abundance of microbial communities of Proteobacteria, Chloroflexi, and Acidobacteria decreased to a large extent from summer to winter, while Firmicutes, Bacteroidetes, and Planctomycetota increased to varying degrees. These dominant bacteria played an important role in the degradation of pollutants such as COD, NH3-N, and TN in wetland systems.

Identifying the geochemical evolution and controlling factors of the shallow groundwater in a high fluoride area, Feng County, China.

Understanding how groundwater is formed and evolves is critical for water resource exploitation and utilization. In this study, hydrochemistry and stable isotope tracing techniques were adopted to determine the key factors influencing groundwater chemical evolution in Feng County. A total of fourteen wells and five surface water samples were investigated in November 2021. The δD and δ18O compositions show that both surface water and groundwater are recharged from atmospheric precipitation. The dominating order of cations and anions in groundwater appears to be Na+ > Mg2+ > Ca2+ > K+ and HCO3- > SO42- > Cl- > NO3- > F-, respectively. The groundwater hydrochemical facies are mainly characterized by HCO3-Ca-Mg and SO4-Cl-Na types. The chemical evolution of groundwater is dominated by water-rock interaction and cation exchange reactions. The major ions in groundwater are mainly controlled by various geogenic processes including halite, gypsum, calcite, dolomite, Glauber's salt, feldspar, and fluorite dissolution/precipitation. Furthermore, the abundant fluoride-bearing sediments, together with low Ca2+, promote the formation of high F- groundwater. Approximately 85.7% and 28.6% of groundwater samples exceeded the permissible limit for F- and NO3- respectively. Apart from geogenic F-, human interventions (i.e., industrial fluoride-containing wastewater discharge and agricultural phosphate fertilizer uses) also regulate the F- enrichment in the shallow groundwater. Nitrate pollution of the groundwater may be attributed to domestic waste and animal feces. Our findings could provide valuable information for the sustainable exploitation of groundwater in the study area and the development of effective management strategies by the authorities.

In-situ photoreduction strategy for synthesis of silver nanoparticle-loaded PVDF ultrafiltration membrane with high antibacterial performance and stability.

Ultrafiltration (UF) technology using polyvinylidene fluoride (PVDF) membrane has been widely applied to water and wastewater treatment due to its low cost and simple operation process. However, PVDF-based UF membrane always encountered the issue of membrane biofouling that greatly impacted the filtration performance. In this study, we prepare a silver nanoparticle (AgNP)-loaded PVDF (Ag/PVDF) UF membrane by an in-situ photoreduction method to mitigate the membrane biofouling. Different from the previously reported method, AgNPs were synthesized in-situ by a UV photoreduction process, in which Ag+ ions were reduced to zero-valent Ag nanoparticles by the photo-induced reducing radicals. Antibacterial experiments showed that the inhibition efficiency of Ag/PVDF membrane to Escherichia coli reached up to ~ 99% after antibacterial treatment for 24 h. In comparison with the pristine PVDF membrane, Ag/PVDF membrane possessed a lower water contact angle (83.7° vs. 38.1°), and its pure water flux increased by 23.7%, and a high bovine serum albumin (BSA) rejection efficiency was maintained. In addition, the high stability of the Ag/PVDF composite membrane was confirmed by the extremely low releasing amount of Ag. This study provides a novel strategy for the preparation of metal nanoparticle-incorporated Ag/PVDF ultrafiltration composite membrane showing favorable antibacterial performance and stability.

The effects of anthropomorphism and multimodal biometric authentication on the user experience of voice intelligence.

Voice intelligence is a revolutionary "zero-touch" type of human-machine interaction based on spoken language. There has been a recent increase in the number and variations of voice assistants and applications that help users to acquire information. The increased popularity of voice intelligence, however, has not been reflected in the customer value chain. Current research on the socio-technological aspects of human-technology interaction has emphasized the importance of anthropomorphism and user identification in the adoption of the technology. Prior research has also pointed out that user perception toward the technology is key to its adoption. Therefore, this research examines how anthropomorphism and multimodal biometric authentication influence the adoption of voice intelligence through user perception in the customer value chain. In this study we conducted a between-subjects online experiment. We designed a 2 × 2 factorial experiment by manipulating anthropomorphism and multimodal biometric authentication into four conditions, namely with and without a combination of these two factors. Subjects were recruited from Amazon MTurk platform and randomly assigned to one of the four conditions. The results drawn from the empirical study showed a significant direct positive effect of anthropomorphism and multimodal biometric authentication on user adoption of voice intelligence in the customer value chain. Moreover, the effect of anthropomorphism is partially mediated by users' perceived ease of use, perceived usefulness, and perceived security risk. This research contributes to the existing literature on human-computer interaction and voice intelligence by empirically testing the simultaneous impact of anthropomorphism and biometric authentication on users' experience of the technology. The study also provides practitioners who wish to adopt voice intelligence in the commercial environment with insights into the user interface design.

Current Status, Challenges, and Policy Recommendations of China's Marine Monitoring Systems for Coastal Persistent Organic Pollution Based on Experts' Questionnaire Analysis.

Persistent organic pollutants (POPs) monitoring and management in typical semi-enclosed bays is a major global environmental issue. This study concentrated on a questionnaire survey and analysis of marine environmental management and monitoring departments at all levels in China, and proposed suggestions on the construction and improvement of POPs monitoring and management system. Results show that POPs are initially involved in China's current marine environmental monitoring system, and the monitoring strength and capability still need to be continuously improved, mainly in the recognition, funding input, relevant standards, monitoring, and evaluation technical regulations of marine environmental POPs monitoring. Therefore, in order to gradually improve the monitoring and management system of China's offshore marine environment POPs, this study suggests starting from four directions: (1) Building POPs monitoring system of a marine ecological environment, and strengthening POPs monitoring in different environmental media; (2) strengthening land-based POPs emission and the related human activities' intensity survey, and establishing a POPs information sharing database; (3) optimizing POPs monitoring technology in the marine environment, and improving POPs supervision and management technical support system; and (4) participating in regional and international marine environment POPs monitoring and evaluation projects, and strengthening the construction of talent teams.

Simultaneous removal of concentrated organics, nitrogen and phosphorus nutrients by an oxygen-limited membrane bioreactor.

Simultaneous removal of organics, nitrogen and phosphorus was achieved in a bench-scale oxygen-limited membrane bioreactor (OLMBR). Due to the limited dissolved oxygen (~ 0.2 mg/L equilibrium concentration) and the increased sludge concentration associated with the hollow fiber membrane, the OLMBR was endowed with an excellent performance on the removal of multi-pollutants. The optimized removal efficiencies of COD, nitrogen (N), and total phosphorus (TP) were approximately 95.5%, 90.0% and 82.6%, respectively (COD/N/P = 500:10:1, influent loading = 5.0 kg COD·m-3·d-1, 35°C). Mass balance and bacterial community analysis indicated that the removal of organic carbon was mainly achieved by the methane production process (67.6%). Short-cut nitrification-denitrification (SCND) was observed as the primary denitrification process in the OLMBR, in which the concentrated organic compounds served as the electron donors for denitrification. Nitrosomonas was observed to be the predominant ammonium-oxidizing bacteria, while nitrite-oxidizing bacteria were almost absent in the microbial community as revealed by the high-throughput sequencing technique. In addition, Euryarchaeota and Candidatus, which were well associated with the process of denitrifying anaerobic methane oxidation, were also detected. Sludge absorption was the main route for TP removal in the OLMBR, and the production of PH3 gas also accounted for 19.4% of TP removal. This study suggested that the interception effect of hollow fiber membrane provided higher sludge concentration, therefore offering more bacteria for pollutant removal. The OLMBR can be used for simultaneous removal of highly concentrated organics and nutrients in livestock and poultry breeding wastewater.

Anthropogenic activities and coastal environmental quality: a regional quantitative analysis in southeast China with management implications.

Regional analysis of environmental issues has always been a hot topic in the field of sustainable development. Because the different levels of economic growth, urbanization, resource endowments, etc. in different regions generate apparently different ecological responses, a better description and comparison across different regions will provide more valuable implications for ecological improvement and policymaking. In this study, seven typical bays in southeast China that are a rapid developing area were selected to quantitatively analyze the relationship between socioeconomic development and coastal environmental quality. Based on the water quality data from 2007 to 2015, the multivariate statistical method was applied to analyze the potential environmental risks and to classify the seven bays based on their environmental quality status. The possible variation trends of environmental indices were predicted based on the cross-regional panel data by Environmental Kuznets Curve. The results showed that there were significant regional differences among the seven bays, especially Quanzhou, Xiamen, and Luoyuan Bays, suffered from severer artificial disturbances than other bays, despite their different development patterns. Socioeconomic development level was significantly associated with some water quality indices (pH, DIN, PO4-P); the association was roughly positive: the areas with higher GDP per capita have some worse water quality indices. In addition, the decreasing trend of pH values and the increasing trend of nutrient concentration in the seven bays will continue in the foreseeable future. In consideration of the variation trends, the limiting nutrient strategy should be implemented to mitigate the deterioration of the coastal environments.

[Effects of submarine topography and water depth on distribution of pelagic fish community in minnan-taiwan bank fishing ground].

According to the fishing record of the light-seine information vessel in Minnan-Taiwan bank ground during 1989 to 1999, the effects of submarine topography and water depth on distribution of pelagic fish community in Minnan-Taiwan bank fishing ground was studied. The results showed that the pelagic fish distributed concentratively, while the submarine topography and water depth varied widely, but in different fishing regions, the distribution of pelagic fishes was uneven. The distribution of fishing yield increased from north to south, and closed up from sides of the bank to south or north in the regions. Pelagic fish distributed mainly in mixed water in the southern Taiwan Strait, and in warm water in the Taiwan Strait. The central fishing grounds were at high salt regions. Close gathering regions of pelagic fish or central fishing ground would be varied with the seasonal variation of mixed water in the southern Taiwan Strait and warm water in the Taiwan Strait. Central fishing ground was not only related to submarine topography and water depth, but also related to wind direction, wind-power and various water systems. In the fishing ground, the gathering depth of pelagic fish was 30-60 m in spring and summer, and 40-80 m in autumn and winter.