"Towards a pollution-free planet"is one of the three strategic objectives proposed in United Nations Environment Programme(UNEP)'s Medium-Term Strategy for 2022-2025 which framed UNEP's contribution in the context of the 2030 Agenda for Sustainable Development and the Decade of Action to deliver the Sustainable Development Goals and beyond.

In this study, we investigated the degradation of surfactant sodium dodecyl benzene sulfonate (SDBS) in aqueous solution using electron beam radiation. The removal efficiency of SDBS approached nearly 100%, achieving a COD removal rate of 7-20% with an absorbed dose of 5.0 kGy. Upon irradiation, several notable changes in SDBS micelles were observed. The absolute value of zeta potential and the average diameter size decreased. SEM observations revealed that the clustered aggregates of SDBS micelles fragmented into irregular filamentous pieces. Moreover, the interfacial tension increased remarkably and approached the level of pure water at 2.5 kGy for SDBS in a pure water solution and 5.0 kGy for SDBS in a brine water solution. The foaming power disappeared for SDBS in pure water and decreased to 20 mm for SDBS in brine water at 10 kGy. The defoaming rate of SDBS solution increased incrementally from an initial range of 1-2 mm/min to 3.0-5.6 mm/min at 5.0 kGy. In summary, when SDBS is decomposed, new system is created with new properties. Electron beam radiation offers a clean and sustainable approach to degrade SDBS in wastewater.

Acidic partial nitritation (PN) is a promising technology to achieve low-cost and energy-efficient shortcut nitrogen removal from wastewater. However, a comprehensive understanding of the acidic PN under dynamic changes of pH in a sequencing batch reactor (SBR) is still lacking. In this study, we successfully established acidic PN (NO2- accumulation ratio >80%) under dynamic pH variation from 7.0 to 4.5 in a lab-scale SBR. By accumulating in situ free nitrous acid (FNA) generation based on the dynamic pH change, acidic PN maintained stability even at a low NH4+ concentration of 100 mg N L-1. The microbial community analysis revealed that two ammonium-oxidizing bacteria (AOB) genera, Nitrosospira and Nitrosomonas, successfully coexisted and cooperated during acidic PN. None of the species of nitrite-oxidizing bacteria (NOB) showed adaptation to intermittent inhibition of in situ FNA even under high DO conditions (>4.0 mg O-2 L-1). Furthermore, we innovatively incorporated the classic nitrification model with the growth and decay of different nitrifying bacterial species and their inhibition by pH, FNA, and free ammonia (FA) to predict the nitrifying microbial communities shifting for establishing acidic PN. The extended model was calibrated by using short-term batch experiments and was validated by using long-term dynamic data of the nitrifying microbial community during SBR operation. The validated model was further used to identify feasible influent conditions for the SBR PN process, including influent HCO3- concentration, NH4+ concentration and molar ratio (HCO3/NH4+). Outcomes from this study support the optimal design of acidic PN-based short-cut nitrogen removal processes for future application.

Although the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been widely detected in wastewater in many countries to track the COVID-19 pandemic development, it is still a lack of clear understanding of the persistence of SARS-CoV-2 in raw sewage, especially after the end of the COVID-19 pandemic event. To fill this knowledge gap, this study conducted a field trial on the SARS-CoV-2 presence in various wastewater facilities after the end of the COVID-19 epidemics in Beijing. The result showed that the wastewater treatment facility is a large SARS-CoV-2 repository. The viral RNA was still present in hospital sewage for 15 days and was continually detected in municipal WWTPs for more than 19 days after the end of the local COVID-19 epidemics. The T90 values of the SARS-CoV-2 RNA in raw wastewater were 17.17-8.42 days in the wastewater at 4 degrees C and 26 degrees C, respectively, meaning that the decay rates of low titer viruses in raw sewage were much faster. The results confirmed that the SARS-CoV-2 RNA could persist in wastewater for more than two weeks, especially at lower temperatures. The sewage systems would be a virus repository and prolong the presence of the residual SARS-CoV-2 RNA. The study could enhance further understanding of the presence of SARS-CoV-2 RNA in raw wastewater.

水资源是人类生产、生活、乃至生命中不可或缺的重要资源.但工业革命以来,世界各国先后出现严重的水污染,大大加重了水资源短缺的问题,并对人类和生物造成了严重的健康危害,中国也不例外. 早在20世纪50年代初,中国就注意到了水污染防治的重要性,采取了很多措施,做了不少工作,半个多世纪以来取得了一定的成就.但应该看到,我们面临的水污染形势还十分严峻,一方面传统的有机污染和氮、磷污染还没有得到完全控制,另一方面随着工业废水排放中的重金属、持久性(难降解)有机物日益增多,在传统的污水处理厂很难得到完善的处理,对人体健康造成了严重的威胁.

In this article, we introduce and analyze an emerging polycentric governance model for addressing wastewater challenges in textile industrial parks in China. Unlike the conventional two-tier model with government and polluters only, the emerging model emphasizes multi-actor participation and presents new possibilities in enhancing the cost-effectiveness and alleviating the compliance deficiency. We introduce the model through a case study of the Binhai textile industrial park. The features of the model include levering the subject of monitoring, allowing collaborative wastewater treatment, employing the administrative power of local governing bodies, and engaging multiple local actors. To explain its formation, we adopt event sequence analysis, and point out the important role of local government as a facilitator and a regulator in the externally generated collaborative governance. We identified its success factors with pattern matching based on polycentric governance theories. We find the involvement of varied actors in the decision-making process of internal wastewater emission standard could lead to applicable policy making with high acceptance, which contributes to the environmental performance. To initiate the transition towards the new model, three conditions are required, including policy support from the government, the establishment of monitoring systems, and capacity building for actors.

In this letter, fully convolutional denoising approximate message passing (FCDAMP) algorithm is proposed by combining fully convolutional denoising networks with learned approximate message passing networks in millimeter-wave massive MIMO system. In particular, an asymmetric neural network architecture is considered that can learn channel structure and extract noise characteristics. Simulation and analysis show that the proposed FCDAMP algorithm satisfies the lower estimation error and the higher achievable sum rate especially in the low SNR. Moreover, the performance can be further improved by increasing the antenna array in massive MIMO system.

Through the survey of employee from environmental monitoring industry, the common used project in environmental monitoring industry was indentified. Based on the survey, the system of monitoring experimental course in applied university was redesigned, so as to promote the operational ability of students and increase the applicability and locality of the course. It aimed to improve the competitiveness of the graduates from applied university in the local industrial environment. Besides, the set of environmental monitoring experimental course in Taizhou University was introduced, including the experimental project, the quantity and schedule of the experimental course. The implementation effect of the system was also analyzed preliminarily.

Linking microbial community structure to physiology and ecological processes is a critical focus of microbial ecology. To understand the microbial functional gene patterns related to soil greenhouse gas [carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O)] emissions under oil contamination, we used functional gene array (GeoChip 5.0) analysis and network methods to investigate the feedback responses of soil microbial functional gene patterns and identify keystone genes in Shengli Oilfield, China. The microbial functional gene number, relative abundance and diversity involved in carbon degradation and nitrogen cycling decreased consistently with the reduced CO2 and N2O flux in oil contaminated soils, whereas the gene number and relative abundance of methane-production related genes increased with contamination. Functional molecular ecological networks were built based on random matrix theory, where network structures and properties showed significantly variation between oil contaminated and uncontaminated soils (P<0.05). Network nodes, connectivity and complexity all reduced under oil contamination. The sensitive and the highest connective genes in the network were identified as keystone genes, based on Mann-Whitney U tests and network analysis. Our findings improved the understanding of the microbe-mediated mechanisms affecting soil greenhouse gas emissions.

Residents’ participation in classification and recycling of urban household solid waste (HSW) is a critical factor for the success of municipal solid waste management. The aim of this study is to investigate the decision-making mechanism of residents’ HSW disposal behaviors by merging the theory of planned behavior and the Attitude-Behavior-Condition theory. In this study, based on the survey data of 709 residents in Suzhou, China and structural equation modeling method, the main factors that affect residents’ HSW disposal behaviors and their degree of influence were analyzed, followed by discussion on decision-making mechanisms. The findings show that residents’ behavioral selection has been significantly related to four intrinsic subjective factors and seven external objective factors, and the combined effect of the latter ones is nearly twice of that of the former ones. Moreover, the convenient of environmental facilities and services are most effective at promoting residents’ participation in HSW classification and recycling. Specifically, the observed variables of publicity and education, accessibility to recycling facilities, accessibility to classification facilities, willingness to participation of classification and residents' environmental awareness are the five most significant factors. The impact of laws and regulations is not significant; however, this may be because that there was no mandatory laws, regulations and incentive mechanisms on HSW classification and recycling in Suzhou in this period, and there is still a big gap and room for improvement in this aspect in mainland China. Finally, the study put forward relevant policy recommendations for the comprehensive management of urban HSW classification and recycling.

Crude oil exploration and related activities cause severe soil contamination and land degradation. However, how soil CH4 and CO2 fluxes respond to oil contamination is poorly understood. To address this question, we conducted in situ investigation of CH4 and CO2 emissions in the Shengli Oilfield, China. CH4 emissions from contaminated soils were 60–1,800 μg·m−2·hr−1, much higher than those from uncontaminated soils (29–33 μg·m−2·hr−1). CO2 fluxes of 2–78 mg·m−2·hr−1 were lower from contaminated soils compared with uncontaminated controls (78–104 mg·m−2·hr−1). The variance of CH4 and CO2 fluxes could be explained to 78.0% by soil properties and oil well age (p < .001) as suggested by the redundancy analysis and the variance partitioning analysis. On the basis of the Illumina MiSeq sequencing of the archaeal 16S rRNA gene, the relative abundance of methanogens over archaea increased by 8 times in contaminated soils compared with that in the uncontaminated soils, suggesting enhanced methanogenesis processes. The proportion of hydrogenotrophic methanogens over the total methanogens increased from 35% in the uncontaminated soil to 43% in the contaminated soils, consistent with the higher apparent fractionation factor (αC) in the stable isotope analysis. Both microbial and isotopic results suggested that the hydrogenotrophic methanogenesis relatively enhanced with the oil contamination, with less dominance of the acetoclastic methanogenesis. The dramatically increased CH4 emissions under oil contamination call for great attention as a potentially important anthropogenic source of CH4 in the atmosphere.

Along with the commercialization of offshore wind energy in China, the South China Sea has been identified as ideal for constructing offshore wind farms, especially for farms consisting of floating wind turbines over deep waters. Since the wind profiles and wave spectra are somewhat primitive for the design of an offshore wind turbine, engineering models describing the wind and wave characteristics in the South China Sea area are necessary for the offshore wind energy exploitation given the meteorological, hydrological, and geographical differences between the South China Sea and the North/Norwegian Sea, where the commonly used wind profile and wave spectrum models were designated. In the present study; a series of numerical simulations were conducted to reveal the wave characteristics in the South China Sea under both typhoon and non-typhoon conditions. By analyzing the simulation results; the applicability of the Joint North Sea Wave Project (JONSWAP) spectrum model; in terms of characterizing the wind-induced wave fields in the South China Sea; was discussed. In detail; the key parameters of the JONSWAP spectrum model; such as the Phillips constant; spectral width parameter; peak-enhancement factor, and high frequency tail decay; were investigated in the context of finding suitable values.

High solid anaerobic digestion (HSAD) is a rapidly developed anaerobic digestion technique for treating municipal sludge, and has been widely used in Europe and Asia. Recently, the enhanced HSAD process with thermal treatment showed its advantages in both methane production and VS reduction. However, the understanding of the microbial community is still poor. This study investigated microbial communities in a pilot enhanced two-stage HSAD system that degraded waste activated sludge at 9% solid content. The system employed process “thermal pre-treatment (TPT) at 70 °C, thermophilic anaerobic digestion (TAD), and mesophilic anaerobic digestion (MAD)”. Hydrogenotrophic methanogens Methanothermobacter spp. dominated the system with relative abundance up to about 100% in both TAD and MAD. Syntrophic acetate oxidation (SAO) bacteria were discovered in TAD, and they converted acetate into H2 and CO2 to support hydrogenotrophic methanogenesis. The microbial composition and conversion route of this system are derived from the high solid content and protein content in raw sludge, as well as the operational conditions. This study could facilitate the understanding of the enhanced HSAD process, and is of academic and industrial importance.

A planar waveguide-based array immunosensor (PWAI) was described, allowing measurements of up to twenty-four analytes in eight separate channels rapidly, sensitively and simultaneously. In this system, a linear laser light created by a line generator was coupled into a planar optical waveguide via a beveled angle, forming eight individual total internal reflection (TIR) lines. A multi-channel microfluidics cell was employed to isolate the parallel TIR lines physically so as to form eight independent flow channels on the same chip, avoiding the cross-reactivity of antibodies and supporting various bioassay conditions. By employing fluorescent detection with fluorophore-labeled antibodies binding to the surface of the waveguide with the analyte derivative covalently attached, the array immunoassays can realize the multi-analyte biosensing. A model was proposed to guide the design of such a planar waveguide-based evanescent wave biosensor. The proposed system was confirmed with the comparable sensitivity with previously reported waveguide biosensor. In addition to being a multi-channel analytical device for the highly sensitive detection of contaminants, the proposed evanescent wave PWAI can provide the dynamic surface-based biomolecular interaction information regarding the affinity and kinetics with high sensitivity.

High-solid anaerobic digestion (HSAD) of sludge has several advantages like smaller reactor, lower energy consumption and less digestate. However, the understanding about the mechanism especially the microbial mechanism is still limited. In this study, microbial communities of a pilot-scale sludge HSAD system at steady state were investigated with 16S rRNA clone library technology. The system employed an enhanced two-phase anaerobic digestion process, i. e. 'hyperthermophilic acidogenesis (70℃, 3 d)-thermophilic methanogenesis (55℃, 12.5 d)' to treat waste activated sludge with a solid content of about 9%. The volatile solid (VS) removal rate was 35.7% and methane yield (CH4/VSremoved) was 0.648 m3·kg-1. The bacterial compositions of the two phases were significantly different:there were plenty of proteolytic bacteria in hyperthermophilic acidogenesis phase; and the bacteria degrading polysaccharides like cellulose and the bacteria utilizing long-chain fatty acids were found in thermophilic methanogenesis phase; some bacteria degrading simple saccharides existed in both phases. In both phases, the dominant archaea were Methanothermobacter. Especially, 100% of the retrieved archaea in the thermophilic methanogenesis phase belonged to genus Methanothermobacter. This indicated that hydrogenotrophic methanogenesis was the predominant methanogenesis pathway in this system since methane was only detected in the methanogenesis phase.