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Wang C, Chang L, Zhang X, Chai H, Huang Y. Promoting oxygen vacancies utility for tetracycline degradation via peroxymonosulfate activation by reduced Mg-doped Co 3O 4: Kinetics and key role of electron transfer pathway. Environ Res 2024; 252:118892. [PMID: 38599451 DOI: 10.1016/j.envres.2024.118892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 03/19/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
Developing cobalt-based catalysts with a high abundance of oxygen vacancies (Vo) and exceptional Vo utility efficiency for the prompt removal of stubborn contaminants through peroxymonosulfate (PMS) activation poses a significant challenge. Herein, we reported the synthesis of the reduced Mg-doped Co3O4 nanosheets, i.e. Mg-doped Co3O4-r, via Mg doping and followed by NaBH4 reduction, aiming to degrade tetracycline (TC). Various characterization results illustrated that NaBH4 reduction imparted higher Vo utility efficiency to Mg-doped Co3O4-r, along with an ample presence of reduced Co2+ species and an increased surface area, thereby substantially elevating PMS activation capability. Notably, Mg-doped Co3O4-r achieved more than 97.9% degradation of 20 mg/L TC within 10 min, showing an over 8-fold increase in reaction rate relative to the Mg-doped Co3O4 (kobs: 0.3285 min-1 vs 0.0399 min-1). The high removal efficiency of TC was sustained across a broad pH range of 3-11, even in the presence of common anions and humic acid. Radical quenching trials, EPR outcomes, and electrochemical analysis indicated that neither radicals nor 1O2 were the primary active species. Instead, electron transfer pathway played a dominant role in TC degradation. The Mg-doped Co3O4-r displayed excellent recyclability and versatility. Even after the fifth cycle, it maintained an impressive 83.0% removal of TC. Furthermore, it exhibited rapid degradation capabilities for various pollutants, including levofloxacin, pefloxacin, ciprofloxacin, malachite green, and rhodamine B. The TC degradation pathway was proposed based on LC-MS determination of its degradation intermediates. This study showcases an innovative strategy for the rational design of an efficient cobalt-based activator, leveraging electron transfer pathways through PMS activation to degrade antibiotics effectively.
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Affiliation(s)
- Cheng Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Southwest University, Chongqing, 400715, China
| | - Lian Chang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing University, Chongqing, 400045, China
| | - Xiaodan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Southwest University, Chongqing, 400715, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing University, Chongqing, 400045, China.
| | - Yuming Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Southwest University, Chongqing, 400715, China.
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Chai H, Russ J, Vardhaman S, Lim CH, Zhang Y. A Bilayer Method for Measuring Toughness and Strength of Dental Ceramics. J Dent Res 2024; 103:419-426. [PMID: 38410925 DOI: 10.1177/00220345231225445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024] Open
Abstract
The ever-increasing usage of ceramic materials in restorative dentistry necessitates a simple and effective method to evaluate flexural strength σF and fracture toughness KC. We propose a novel method to determine these quantities using a bilayer specimen composed of a brittle plate adhesively bonded onto a transparent polycarbonate substrate. When this bilayer structure is placed under spherical indentation, tunneling radial cracks initiate and propagate in the lower surface of the brittle layer. The failure analysis is based on previous theoretical relationships, which correlate σF with the indentation force P and layer thickness d, and KC with P and mean length of radial cracks. This work examines the accuracy and limitations of this approach using a wide range of contemporary dental ceramic materials. The effect of layer thickness, indenter radius, load level, and length and number of radial cracks are carefully examined. The accuracy of the predicted σF and KC is similar to those obtained with other concurrent test methods, such as biaxial flexure and 3-point bending (σF), and bending specimens with crack-initiation flaws (KC). The benefits of the present approach include treatment for small and thin plates, elimination of the need to introduce a precrack, and avoidance of dealing with local material nonlinearity effects for the KC measurements. Finally, the bilayer configuration resembles occlusal loading of a ceramic restoration (brittle layer) bonded to a posterior tooth (compliant substrate).
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Affiliation(s)
- H Chai
- School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - J Russ
- School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - S Vardhaman
- Department of Preventive and Restorative Sciences, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA, USA
- College of Dental Medicine, Columbia University, New York, NY, USA
| | - C H Lim
- Department of Preventive and Restorative Sciences, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA, USA
| | - Y Zhang
- Department of Preventive and Restorative Sciences, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA, USA
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Kong Z, Song Y, Xu M, Yang Y, Wang X, Ma H, Zhi Y, Shao Z, Chen L, Yuan Y, Liu F, Xu Y, Ni Q, Hu S, Chai H. Multi-media interaction improves the efficiency and stability of the bioretention system for stormwater runoff treatment. Water Res 2024; 250:121017. [PMID: 38118254 DOI: 10.1016/j.watres.2023.121017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 11/21/2023] [Accepted: 12/11/2023] [Indexed: 12/22/2023]
Abstract
Bioretention systems are one of the most widely used stormwater control measures for urban runoff treatment. However, stable and effective dissolved nutrient treatment by bioretention systems is often challenged by complicated stormwater conditions. In this study, pyrite-only (PO), pyrite-biochar (PB), pyrite-woodchip (PW), and pyrite-woodchip-biochar mixed (M) bioretention systems were established to study the feasibility of improving both stability and efficiency in bioretention system via multi-media interaction. PB, PW, and M all showed enhanced dissolved nitrogen and/or phosphorus removal compared to PO, with M demonstrating the highest efficiency and stability under different antecedent drying durations (ADD), pollutant levels, and prolonged precipitation depth. The total dissolved nitrogen and dissolved phosphorus removal in M ranged between 64%-86% and 80%-95%, respectively, with limited organic matter and iron leaching. Pore water, microbial community, and material analysis collectively indicate that pyrite, woodchip, and biochar synergistically facilitated multiple nutrient treatment processes and protected each other against by-product leaching. Pyrite-woodchip interaction greatly increased nitrate removal by facilitating mixotrophic denitrification, while biochar further enhanced ammonium adsorption and expanded the denitrification area. The Fe3+ generated by pyrite aerobic oxidation was adsorbed on the biochar surface and potentially formed a Fe-biochar composite layer, which not only reduced Fe3+-induced pyrite excessive oxidation but also potentially increased organic matter adsorption. Fe (oxyhydr)oxides intermediate product formed by pyrite oxidation, in return, controlled the phosphorus and organic matter leaching from biochar and woodchip. Overall, this study demonstrates that multi-media interaction may enable bioretention systems to achieve stable and effective urban runoff treatment.
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Affiliation(s)
- Zheng Kong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Yunqian Song
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Mei Xu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yan Yang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China
| | - Xinyue Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yue Zhi
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Lei Chen
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yunsong Yuan
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Fujian Liu
- China Construction Installation Group Co. LTD, Nanjing, 210023, China
| | - Yanhong Xu
- China Construction Installation Group Co. LTD, Nanjing, 210023, China
| | - Qichang Ni
- China Construction Installation Group Co. LTD, Nanjing, 210023, China
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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Liu Y, Liu Y, Zhao T, He Y, Zhu T, Chai H, Peng L. Smaller Aerobic Granules Significantly Reduce N 2O Production by Ammonia-Oxidizing Bacteria: Evidences from Biochemical and Isotopic Analyses. Environ Sci Technol 2024; 58:545-556. [PMID: 38111342 DOI: 10.1021/acs.est.3c06246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
The mitigation of nitrous oxide (N2O) is of primary significance to offset carbon footprints in aerobic granular sludge (AGS) systems. However, a significant knowledge gap still exists regarding the N2O production mechanism and its pathway contribution. To address this issue, the impact of varying granule sizes, dissolved oxygen (DO), and nitrite (NO2-) levels on N2O production by ammonia-oxidizing bacteria (AOB) during nitrification in AGS systems was comprehensively investigated. Biochemical and isotopic experiments revealed that increasing DO or decreasing NO2- levels reduced N2O emission factors (by 13.8 or 19.5%) and production rates (by 0.08 or 0.35 mg/g VSS/h) via weakening the role of the AOB denitrification pathway since increasing DO competed for more electrons required for AOB denitrification. Smaller granules (0.5 mm) preferred to diminish N2O production via enhancing the role of NH2OH pathway (i.e., 59.4-100% in the absence of NO2-), while larger granules (2.0 mm) induced conspicuously higher N2O production via the AOB denitrification pathway (approximately 100% at higher NO2- levels). Nitrifying AGS systems with a unified size of 0.5 mm achieved 42% N2O footprint reduction compared with the system with mixed sizes (0.5-2.0 mm) under optimal conditions (DO = 3.0 mg-O2/L and NO2- = 0 mg-N/L).
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Affiliation(s)
- Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yingrui Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tianhang Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yanying He
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tingting Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Lai Peng
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
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Zhou T, Xiang Y, Liu S, Ma H, Shao Z, He Q, Chai H. Microbial community dynamics and metagenomics reveal the potential role of unconventional functional microorganisms in nitrogen and phosphorus removal biofilm system. Sci Total Environ 2023; 905:167194. [PMID: 37741388 DOI: 10.1016/j.scitotenv.2023.167194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/24/2023] [Accepted: 09/16/2023] [Indexed: 09/25/2023]
Abstract
The conventional functional microorganisms for nitrogen and phosphorus removal, such as Nitrosomonas, Nitrobacter, Nitrospira and Candidatus Accumulibacter, were hotspots in past research. However, the role of diverse unconventional functional microorganisms was neglected. In this study, a biofilm system was developed to explore the potential role of unconventional functional microorganisms in nutrients removal. According to the results of microbial community dynamics and metagenomics, complete ammonia oxidizing (comammox) bacteria was 20 times more abundant than ammonia-oxidizing bacteria (AOB) at day 121 and its abundance of amoA gene was almost the same as AOB. Although Nitrospira dominated the nitrite-oxidizing bacteria (NOB), diverse unconventional nxrB-containing microorganisms, particularly Chloroflexi, also significantly contributed to the nitrite oxidation. Binning analysis showed that Myxococcota-affiliated Haliangium had the necessary genes owns by phosphorus-accumulating organisms (PAO) and was likely to be the primary PAO since its abundance (6.38 %) was much higher than other conventional PAO (0.70 %). Comparing metagenome-assembled genomes of comammox bacteria with AOB and ammonia-oxidizing archaea (AOA), it possessed potential metabolic versatility in hydrogen and phosphorus, which may be the primary reason for the positive effect of the alternating anaerobic and aerobic conditions on the enrichment of comammox bacteria. Collectively, our findings broaden the understanding on the microbial mechanism of nitrogen and phosphorus removal in biofilm system.
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Affiliation(s)
- Tengzhi Zhou
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yu Xiang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; School of Architecture and Civil engineering, Xihua University, Chengdu 610039, China
| | - Shiyi Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Department of Microbiology, Radboud University, Heyendaalseweg 135, Nijmegen 6525 AJ, the Netherlands
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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Xiang Y, Zhou T, Deng S, Shao Z, Liu Y, He Q, Chai H. Nitrite improved nitrification efficiency and enriched ammonia-oxidizing archaea and bacteria in the simultaneous nitrification and denitrification process. Water Res X 2023; 21:100204. [PMID: 38098882 PMCID: PMC10719579 DOI: 10.1016/j.wroa.2023.100204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/18/2023] [Accepted: 10/02/2023] [Indexed: 12/17/2023]
Abstract
Simultaneous nitrification and denitrification (SND) is effective and energy-saving for wastewater treatment. As an inevitable intermediate product in the SND process, nitrite affects the efficiency of ammonia oxidation and the composition of nitrifiers. To investigate the impact of nitrite on ammonia oxidation efficiency, two reactors performing SND were respectively operated without nitrite (R1 as control) and with 20 mg N/L nitrite addition (R2 as experimental). The total nitrogen removal efficiency was 74.5% in R1 while 99.0% in R2. With nitrite addition (i.e., 20 mg N/L), the ammonia removal rate in R2 increased to 4.5 times of that in R1. The ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) contributed to respective around 46.9% and 41.8% ammonia removal in R2 based on the results of experiments with specific inhibitors. The number of respective AOA and AOB ammonia monooxygenase gene (amoA) copies increased by 280 and 30 times due to nitrite addition, according to the qPCR results. The high-throughput sequencing results illustrated the increase of dominant AOB species from 0.40% in R1 to 1.59% in R2 and the phylogenetic tree analysis revealed a close link to Nitrosospira multiformis. These results indicated that the ammonia removal efficiency was improved and AOA/AOB were enriched by nitrite addition. The specific nitrite reductases in AOA and AOB boosted the adaptation of nitrite addition. This study demonstrated the positive impacts of nitrite addition on the ammonia removal efficiency and rate in the SND process.
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Affiliation(s)
- Yu Xiang
- School of Architecture and Civil Engineering, Xihua University, Chengdu 610039, China
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Tengzhi Zhou
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Siping Deng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
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Yang Y, Kong Z, Ma H, Shao Z, Wang X, Shen Y, Chai H. Insights into the transport and bio-degradation of dissolved inorganic nitrogen in the biochar-pyrite amended stormwater biofilter using dynamic modeling. J Environ Manage 2023; 347:119152. [PMID: 37774660 DOI: 10.1016/j.jenvman.2023.119152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/04/2023] [Accepted: 09/23/2023] [Indexed: 10/01/2023]
Abstract
The stormwater biofilter is a prevailing green infrastructure for urban stormwater management, but it is less effective in dissolved nitrogen removal, especially for nitrate. The mechanism that governs the nitrate leaching and performance stability of stormwater biofilters is poorly understood. In this study, a water quality model was developed to predict the ammonium and nitrate dynamics in a biochar-pyrite amended stormwater biofilter. The transport of dissolved nitrogen species was described by advection-dispersion models. The kinetics of adsorption and pyrite-based autotrophic denitrification are included in the model and simulated with a steady-state saturated flow. The model was calibrated and validated using eleven storm events. The modeling results reveal that the contribution of pyrite-based autotrophic denitrification to nitrate leaching alleviation improves with the increased drying duration. The nitrate removal efficiency was affected by a series of design parameters. Pyrite filling rate has a minor effect on nitrate removal promotion. Service area ratio and submerged zone depth are the key parameters to prevent nitrate leaching, as they influence the emergence and discharge time of nitrate breakthrough. The high inflow volume (high service area ratio) and small submerged zone can lead to earlier and increased discharge of peak nitrate otherwise the peak nitrate could be retained in the submerged zone and denitrified during the drying period. The developed mechanistic model provides a useful tool to evaluate the treatment ability of stormwater biofilters under varying conditions and offers a guideline for biofilter design optimization.
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Affiliation(s)
- Yan Yang
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China; Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Zheng Kong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China; Australian Centre for Water and Environmental Biotechnology (ACWEB, Formerly AWMC), The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Xinyue Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Yu Shen
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China; Chongqing South-to-Thais Environmental Protection Technology Research Institute Co., Ltd., Chongqing, 400060, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
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Zhou T, Xiang Y, Liu S, Shao Z, Liu Y, Ma H, He Q, Chai H. Insights into simultaneous nitrogen and phosphorus removal in biofilm: The overlooked comammox Nitrospira and the positive role of glycogen-accumulating organisms. Sci Total Environ 2023; 887:164130. [PMID: 37182783 DOI: 10.1016/j.scitotenv.2023.164130] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/24/2023] [Accepted: 05/09/2023] [Indexed: 05/16/2023]
Abstract
Simultaneous nitrogen and phosphorus removal (SNPR) biofilm system is an effective wastewater treatment process. However, the understanding on the mechanism of functional microorganisms driving SNPR is still limited, especially the role of complete ammonia oxidation (comammox) Nitrospira and glycogen-accumulating organisms (GAO). In this study, a sequencing batch biofilm reactor (SBBR) performing SNPR was operated for 249 d. Based on the 16S rRNA gene, comammox amoA amplicon sequencing, metagenomics and batch experiment, we found that comammox Nitrospira was the main ammonia-oxidizing microorganisms (AOM) and provided nitrite for anaerobic ammonia oxidation (anammox) bacteria (AnAOB). Besides, GAO was dominated by the bacteria of genus Defluviicoccus and played a primary role in reducing nitrate rather than nitrite. Fluorescent in situ hybridization (FISH) analysis confirmed that Nitrospira was enriched in the inner layer of the biofilm. Thus, we put forward a novel insight into the mechanism of SNPR biofilm system. Comammox Nitrospira was responsible for nitrite and nitrate production in the inner biofilm, and AnAOB consumed the produced nitrite during the anammox process. While GAO reduced nitrate to nitrite and polyphosphate-accumulating organisms (PAO) converted nitrite to dinitrogen via denitrifying phosphorus removal in the outer biofilm. These findings provide a new understanding in SNPR biofilm system.
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Affiliation(s)
- Tengzhi Zhou
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yu Xiang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; School of Architecture and Civil engineering, Xihua University, Chengdu 610039, China
| | - Shiyi Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Department of Microbiology, RIBES, Radboud University, Heyendaalseweg 135, Nijmegen, AJ 6525, the Netherlands
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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Cheng C, Chang L, Zhang X, Deng Q, Chai H, Huang Y. Interface engineering-induced perovskite/spinel LaCoO 3/Co 3O 4 heterostructured nanocomposites for efficient peroxymonosulfate activation to degrade levofloxacin. Environ Res 2023; 229:115994. [PMID: 37105283 DOI: 10.1016/j.envres.2023.115994] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/09/2023] [Accepted: 04/24/2023] [Indexed: 05/05/2023]
Abstract
Conventional perovskite oxides (ABO3) tend to suffer from their inactive surfaces and limited active sites that reduce their catalytic activity and stability, while interface engineering is a facile modulating technique to boost the catalyst's inherent activity by constructing heterogeneous interfaces. In this study, perovskite/spinel LaCoO3/Co3O4 nanocomposites with heterogeneous interfaces were synthesized via sol-gel and in-situ gradient etching methods to activate peroxymonosulfate (PMS) for degrading levofloxacin (LEV). LaCoO3 on the surface was etched into spinel Co3O4, and LaCoO3/Co3O4 nanocomposites with two crystal structures of perovskite and spinel were successfully formed. The surface-modified LaCoO3/Co3O4 exhibited superior catalytic performance with a reaction rate constant more than 2 times that of the original LaCoO3, as well as excellent pH adaptability (3-11) and reusability (more than 6 recyclings) for LEV degradation. Besides, multiple characterization techniques were carried out to find that LaCoO3/Co3O4 possessed a larger specific surface area and richer oxygen vacancies after surface modification, which provided more active sites and accelerated mass transfer rate. The mechanism of reactive oxygen species involved in the reaction system was proposed that LaCoO3/Co3O4 not only reacted with PMS directly to produce SO4•- and •OH but also its surface hydroxyl group helped to form the [≡Co(Ⅲ)OOSO3]+ reactive complex with PMS to produce O2•- and 1O2. In addition, electrochemical experiments demonstrated that the surface electronic structure of LaCoO3/Co3O4 was effectively regulated, exhibiting a faster electron transfer rate and facilitating the redox process. By detecting and identifying degradation intermediates, three degradation pathways for LEV were proposed. Our work provided profound insights into the design of efficient and long-lasting catalysts for advanced oxidation processes.
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Affiliation(s)
- Cheng Cheng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Lian Chang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Xiaodan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China
| | - Qingchen Deng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
| | - Yuming Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China.
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10
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Weng Z, Ma H, Ma J, Kong Z, Shao Z, Yuan Y, Xu Y, Ni Q, Chai H. Corncob-pyrite bioretention system for enhanced dissolved nutrient treatment: Carbon source release and mixotrophic denitrification. Chemosphere 2022; 306:135534. [PMID: 35772517 DOI: 10.1016/j.chemosphere.2022.135534] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/07/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
Solid biomass waste amendment and substrates modification in bioretention systems have been increasingly used to achieve effective dissolved nutrients pollution control in stormwater runoff. However, the risk of excess chemical oxygen demand (COD) leaching from organic carbon sources is often overlooked on most occasions. Pyrite is an efficient electron donor for autotrophic denitrification, but little is known about the efficacy of autotrophic-heterotrophic synergistic effect between additional carbon source and pyrite in bioretention. Here, four bioretention columns (i.e., corncob column (C), pyrite column (P), the corncob-pyrite layered column (L-CP), and the corncob-pyrite mixed column (M-CP)) were designed and filled with soil, quartz sand, and modified media to reveal the synergistic effects. The results showed that the corncob-pyrite layered bioretention could maintain low COD effluent concentration with high stability and efficiency in treating dissolved nutrients. When the influent nitrogen and phosphorus concentrations were 8.46 mg/L and 0.94 mg/L, the average removal rates of ammonia nitrogen, total inorganic nitrogen, and phosphate were 83.6%, 70.52%, and 76.35%, respectively. The scouring experiment showed that placing the corncob in the mulch layer was beneficial to the sustained release of dissolved organic carbon (DOC). Erosion pits were found in the SEM images of used pyrite, indicating that autotrophic denitrifying bacteria in the bioretention could react with pyrite as an electron donor. The relative abundance of Thiobacillus in the submerged zone of the corncob-pyrite layered bioretention reached 38.39%, indicating that the carbon source in the mulch layer increased the relative abundance of Thiobacillus. Coexisting heterotrophic and autotrophic denitrification in this bioretention created a more abundant microbial community structure in the submerged zone. Overall, the corncob-pyrite layered bioretention is highly promising for stormwater runoff treatment, with effective pollution removal and minimal COD emission.
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Affiliation(s)
- Zhongshuai Weng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Jingchen Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zheng Kong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, QLD 4072, Australia
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Yunsong Yuan
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yanhong Xu
- China Construction Installation Group Co. Ltd, Nanjing 210023, China
| | - Qichang Ni
- China Construction Installation Group Co. Ltd, Nanjing 210023, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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11
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Kong Z, Ma H, Song Y, Wang X, Li L, Yuan Y, Shao Z, Chai H. A long term study elucidates the relationship between media amendment and pollutant treatment in the stormwater bioretention system: Stability or efficiency? Water Res 2022; 225:119124. [PMID: 36162295 DOI: 10.1016/j.watres.2022.119124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 08/22/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
Media amendment has been more and more frequently tested in stormwater bioretention systems for enhanced runoff pollutant treatment. However, few studies systematically evaluated the amended system over a long time span, which hindered the further optimization of the proposed amended media. In this study, biochar-pyrite system (PB), conventional sand system (SB), and biochar-woodchip system (WB) were established and operated for 26 months. Media amendment greatly enhanced the dissolved nutrient removal, the highest total dissolved nitrogen removal in PB and WB were 65.6±3.6% and 68.2±2.5%, respectively. Compared with PB, WB could maintain excellent nitrogen removal under long-term operation. In contrast, PB demonstrated stable and more effective total dissolved phosphorus removal during all stages (73.1±3.1%-80.3±4.1%). A high content of phosphorus and organic matter was leached in WB especially at initial operation, while the initial pollutant leaching in PB and SB is much lower, about one-third of WB. Microbial and metabolic function analysis indicated that the microbial community in the bioretention system is complicated and stable. Media amendment enhanced microbial diversity and the relative abundance of functional genera related to nitrogen (Nitrospira, Thauera, Denitratisoma, etc.), sulfur (Thiobacillus, Geobacter, Desulfovibrio, etc.), and carbon cycles (cellulomonas, saccharimonadales, and SBR1031, etc.), which well explained the enhanced pollutant removal and by-product leaching in different systems. Overall, the current study indicates that although media amendment is conducive to enhanced dissolved nutrient removal in bioretention systems, it can hardly maintain both stability and efficiency from initial set-up to long-term operation. In practical application, catchment characteristics, prioritized pollutants, meteorological factors, etc. should all be considered before choosing suitable amended media and its design factors, thereby maximising the stability and efficiency of the bioretention system.
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Affiliation(s)
- Zheng Kong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yunqian Song
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xinyue Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Liqing Li
- School of Environmental Science, China University of Geosciences, Wuhan 430074, China
| | - Yunsong Yuan
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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12
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Yang Y, Li M, Zheng X, Ma H, Nerenberg R, Chai H. Extracellular DNA plays a key role in the structural stability of sulfide-based denitrifying biofilms. Sci Total Environ 2022; 838:155822. [PMID: 35561912 DOI: 10.1016/j.scitotenv.2022.155822] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Sulfide-based biofilm processes are increasingly used for wastewater denitrification, yet little is known about the extracellular polymeric substance (EPS) composition of sulfide-oxidizing biofilms. This can have an important impact on biofilm mechanical strength and stability. In this research, the properties and roles of EPS components in biofilm stability were investigated. Weak biofilm stability characterized by high roughness and numerous "needle" structures was visualized by optical coherence tomography (OCT) and microscopy. A high abundance of extracellular DNA (eDNA) and a low protein to polysaccharide ratio were found in the biofilm. The roles of eDNA, protein and polysaccharide in biofilm cohesion and adhesion were identified through enzyme treatment and atomic force microscopy (AFM). The enzymatic hydrolysis of eDNA increased the elastic modulus of biofilms by 57 times and reduced the adhesion energy by 96%. The hydrolysis of proteins led to an increase of elastic modulus by 27 times and a loss of adhesion energy by 95.5%. The enzymatic hydrolysis of polysaccharides caused minimal changes in elastic modulus and adhesion energy. These results suggest that eDNA was the key EPS component for biofilm cohesion and adhesion, possibly because it provided special binding sites and can form strong cross-linking with magnesium or other multivalent cations. This study provided new insights into the role of eDNA in biofilm stability and shed light on the development of sulfide-based denitrifying biofilms.
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Affiliation(s)
- Yan Yang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Mengfei Li
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Xiong Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Haiyuan Ma
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Robert Nerenberg
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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13
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Yang Y, Perez Calleja P, Liu Y, Nerenberg R, Chai H. Assessing Intermediate Formation and Electron Competition during Thiosulfate-Driven Denitrification: An Experimental and Modeling Study. Environ Sci Technol 2022; 56:11760-11770. [PMID: 35921133 DOI: 10.1021/acs.est.2c03937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
There is increasing interest in thiosulfate-driven denitrification for low C/N wastewater treatment, but the denitrification performance varies with the thiosulfate oxidation pathways. Models have been developed to predict the products of denitrification, but few consider thiosulfate reduction to elemental sulfur (S0), an undesirable reaction that can intensify electron competition with denitrifying enzymes. In this study, the model using indirect coupling of electrons (ICE) was developed to predict S0 formation and electron competition during thiosulfate-driven denitrification. Kinetic data were obtained from sulfur-oxidizing bacteria (SOB) dominated by the branched pathway and were used to calibrate and validate the model. Electron competition was investigated under different operating conditions. Modeling results reveal that electrons produced in the first step of thiosulfate oxidation typically prioritize thiosulfate reduction, then nitrate reduction, and finally nitrite reduction. However, the electron consumption rate for S0 formation decreases sharply with the decline of thiosulfate concentration. Thus, a continuous feeding strategy was effective in alleviating the competition between thiosulfate reduction and denitrifying enzymes. Electron competition leads to nitrite accumulation, which could be a reliable substrate for anammox. The model was further evaluated with anammox integration. Results suggested that the branched pathway and continuous supply of thiosulfate are favorable to create a symbiotic relationship between SOB and anammox.
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Affiliation(s)
- Yan Yang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Patricia Perez Calleja
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China
| | - Robert Nerenberg
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
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14
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Chai H, Qing P. [A review of the influence of the 1956 Senior Teacher Training Program on Medical History]. Zhonghua Yi Shi Za Zhi 2022; 52:227-234. [PMID: 36008312 DOI: 10.3760/cma.j.cn112155-20210825-00101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The 1956 Senior Teacher Training Program on Medical History, hosted by the Institute of Traditional Chinese Medicine of the Ministry of Health, was the first teacher training program on the history of medicine in higher education in P. R. China. It was designed in the context of "Learning from the Soviet Union" for teaching reformation, "Integrating Western and Traditional Chinese Medicine" and performing the policy of "Blossom of Hundred Flowers and Contention of Hundred Schools of Thought" (by Mao Zedong for encouraging a variety of thinking conflicts) after the birth of the New China. The teaching management for the program was well organised, with a strong staff, and outcomes. A few of the trainees from this program were engaged in teaching and research of the history of medicine, and made outstanding academic achievements and promoted the teaching and research of the history of medicine in Chinese universities in the second half of the 20th century. This program also provides a valuable reference for teacher training programs as well as teaching and research of medical history today.
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Affiliation(s)
- H Chai
- West China School of Medicine / West China Hospital, Sichuan University, Chengdu 610041, China
| | - P Qing
- West China School of Medicine / West China Hospital, Sichuan University, Chengdu 610041, China
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15
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Cheng C, He Q, Zhang J, Chai H, Yang Y, Pavlostathis SG, Wu H. New insight into ammonium oxidation processes and mechanisms mediated by manganese oxide in constructed wetlands. Water Res 2022; 215:118251. [PMID: 35278914 DOI: 10.1016/j.watres.2022.118251] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/24/2022] [Accepted: 03/05/2022] [Indexed: 06/14/2023]
Abstract
Manganese oxide (MnOx) mediated ammonium (NH4+) oxidation in wetlands is receiving increased interest; however, the biochemical mechanisms of this process are vague due to only few studies have focused on terrestrial ecosystems. In this study, three subsurface flow constructed wetlands (CWs), high/low content of Mn-sand CW (HMn-CW/LMn-CW) and quartz sand CW (C-CWs), were set up to explore the extent of ammonium nitrogen (NH4+-N) removal and underlying mechanisms. According to the surface characteristics of Mn-sand, MnOx nanospheres were loaded as birnessite on the sand, while changes of the Mn/N contents indicated involvement of Mn-sand in NH4+-N removal. During the 120-day operation, higher extent of NH4+-N removal with decreased nitrous oxide (N2O) emission was achieved in the HMn-CW (76%) than in the LMn-CW (73%) and C-CW (67%). According to the distribution of nitrogen compounds and Mn2+, Mn-sand in the HMn-CW delayed oxidation of NH4+ and production of nitrate and nitrite. High abundance of Zooloea and Psychrobacter was observed in the Mn-sand layer of HMn-CW, corresponding to a higher observed NH4+-N removal. NH4+ oxidation to hydroxylamine and then to nitrite was enhanced in HMn-CW due to ammonia monooxygenase genes being promoted. The decrease of N2O emission was closely related to the genus TM7a, verified by Pearson correlation analysis. Our findings expand the knowledge of MnOx-mediated NH4+ oxidation in wetlands and support the potential application of manganese oxide for effective nitrogen removal in CWs.
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Affiliation(s)
- Cheng Cheng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China.
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Jian Zhang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, PR China; School of Environmental Science and Engineering, Shandong University, Qingdao 266237, PR China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Yujing Yang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Spyros G Pavlostathis
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Haiming Wu
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, PR China.
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16
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Liu Y, Zhu T, Ren S, Zhao T, Chai H, Xu Y, Peng L, Liu Y. Contribution of nitrification and denitrification to nitrous oxide turnovers in membrane-aerated biofilm reactors (MABR): A model-based evaluation. Sci Total Environ 2022; 806:151321. [PMID: 34743877 DOI: 10.1016/j.scitotenv.2021.151321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
As a novel and sustainable technology, membrane-aerated biofilm reactors (MABR) performing simultaneous nitrification and denitrification face the challenge of undesirable nitrous oxide (N2O) emission. Thereby, a comprehensive analysis of N2O turnover pathways and the affecting parameters in MABR are demanded for N2O mitigation strategies. In this work, a mathematical model describing three N2O turnovers pathways was studied to uncover the underlying mechanisms and the impacts of operational conditions on N2O turnovers in MABR system performing simultaneous nitrification and denitrification. The modeling results demonstrate that higher oxygen surface loading, longer hydraulic retention time (HRT) and lower influent chemical oxygen demand (COD) significantly induce higher N2O production factor (0.18%-3.3%). N2O turnovers are mainly regulated by the hydroxylamine (NH2OH) pathway and heterotrophic bacteria (HB) denitrification, accounting for 76%-87% and 10%-21%, respectively. In contrast, the thicker biofilm (i.e., 400-600 μm) causes lower N2O production factor (<0.13%), due to the shift of N2O turnover pathways to the ammonium oxidizing bacteria (AOB) denitrification pathway (7.1%-9.3%) and HB denitrification (90.7%-92.9%). Meanwhile, the result of in-biofilm N2O conversion rates shows that the NH2OH pathway and HB denitrification become the predominant N2O production pathway at the inner zone (0-160 μm) and the outer zone (290-350 μm) of the biofilm in MABR, respectively. The biofilm thickness at 160-280 μm can thus be regarded as an optimal zone to reduce N2O production in MABR, due to more electrons preferentially used for N2O reduction. The relatively low N2O production factor (<0.5%) together with >80% total nitrogen (TN) removal in MABR can be achieved by controlling the oxygen surface loading (1.821-3.641 g/m2/d) and influent COD concentrations (285-500 mg/L) within a certain range.
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Affiliation(s)
- Yingrui Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tingting Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Shuqi Ren
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tianhang Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yifeng Xu
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Lai Peng
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
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Shao Z, Xu L, Chai H, Yost SA, Zheng Z, Wu Z, He Q. A Bayesian-SWMM coupled stochastic model developed to reconstruct the complete profile of an unknown discharging incidence in sewer networks. J Environ Manage 2021; 297:113211. [PMID: 34284327 DOI: 10.1016/j.jenvman.2021.113211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 05/25/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Unknown illicit discharges from manufactories often contain toxic chemical matters that are detrimental to the receiving waterbody by deteriorating the performance of wastewater treatment plants. Numerical models that identify these sources and reconstruct the discharging profiles are highly desired for environment management purpose. In this study, a stochastic source identification model that couples Bayesian inference with SWMM is developed to reconstruct the profile of an instantaneous dumpling incidence in sewer networks. The unknown source parameters include location, dumping rate and time of the dumping incidence. Key factors that impact the convergence and performance of the model including walking step size, numbers of unknown source parameters and numbers of monitoring sites are investigated. Results show that the Bayesian-SWMM coupled model is effective and accurate in identifying the unknown sources parameters in an instantaneous dumping event. It is also found that walking step size is crucial for the results to converge to true solutions. Furthermore, it shows that the identified results are highly dependent on the numbers of unknown source parameters. More unknowns result to unsatisfying results. However, the study shows that this limitation could be significantly reduced by using more monitoring site data. One contribution of the study is that errors from measurements and numerical simulation are considered in the identification while results are presented in probabilities with all possible values revealed. This feature is highly practical and efficient when it comes to assist further field screening efforts to pinpoint the true sources.
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Affiliation(s)
- Zhiyu Shao
- Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area, Chongqing University, Chongqing, 400030, China; College of Environment and Ecology, Chongqing University, Chongqing, 400030, China.
| | - Lei Xu
- Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area, Chongqing University, Chongqing, 400030, China; College of Environment and Ecology, Chongqing University, Chongqing, 400030, China
| | - Hongxiang Chai
- Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area, Chongqing University, Chongqing, 400030, China; College of Environment and Ecology, Chongqing University, Chongqing, 400030, China
| | - Scott A Yost
- Department of Civil Engineering, University of Kentucky, Lexington, 40506, USA
| | - Zuole Zheng
- Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area, Chongqing University, Chongqing, 400030, China; College of Environment and Ecology, Chongqing University, Chongqing, 400030, China
| | - Zhengsong Wu
- Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area, Chongqing University, Chongqing, 400030, China; College of Environment and Ecology, Chongqing University, Chongqing, 400030, China
| | - Qiang He
- Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area, Chongqing University, Chongqing, 400030, China; College of Environment and Ecology, Chongqing University, Chongqing, 400030, China
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Kong Z, Song Y, Shao Z, Chai H. Biochar-pyrite bi-layer bioretention system for dissolved nutrient treatment and by-product generation control under various stormwater conditions. Water Res 2021; 206:117737. [PMID: 34637973 DOI: 10.1016/j.watres.2021.117737] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/27/2021] [Accepted: 09/30/2021] [Indexed: 06/13/2023]
Abstract
Bioretention system with modified media has been increasingly used to control dissolved nutrients in stormwater runoff. However, complicated removal processes and improper design have made most of them hardly achieve comprehensive dissolved nutrient removal and even show by-product generation problem, especially during extreme stormwater events. Here, a modified biochar-pyrite (FeS2) bi-layer bioretention system was developed and tested under various stormwater conditions with conventional sand-based and woodchip-based bioretention systems as controls. The modified system showed high stability and efficiency for dissolved nutrient treatment. The removal of dissolved organic nitrogen, ammonium, total dissolved nitrogen, and total dissolved phosphorus were 86.3-93.0%, 95.3-98.1%, 41.4-76.5%, and 69.7-88.2%, respectively. Stormwater conditions only influence nitrate removal which decreased with the increase of total received volume and increased with the extension of antecedent drying duration. Net sulfate and total iron generation were very low, less than 8 mg/L and 0.15 mg/L, respectively. Several microbiology, spectroscopy, and media related tests further demonstrated that the vadose zone and submerged zone showed synergy effects during operation. Biochar addition facilitated ammonium adsorption, nitrification, and in situ denitrification in the vadose zone. It also intercepted dissolved oxygen, which alleviated aerobic pyrite oxidation and created an anoxic condition for the submerged zone. Meanwhile, the pyrite-modified submerged zone achieved stable mixotrophic denitrification. The generated iron intermediate products further controlled phosphorus from both influent and vadose zone leaching into stable forms. Mixotrophic denitrification and potential sulfate reduction processes also reduce sulfate generation. Overall, the biochar-pyrite bi-layer bioretention is a highly promising technology for stormwater runoff treatment, with effective dissolved nutrient removal and minimal by-product generation in various stormwater conditions.
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Affiliation(s)
- Zheng Kong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yunqian Song
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zhiyu Shao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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Yang X, Xie X, Li S, Zhang W, Zhang X, Chai H, Huang Y. The POM@MOF hybrid derived hierarchical hollow Mo/Co bimetal oxides nanocages for efficiently activating peroxymonosulfate to degrade levofloxacin. J Hazard Mater 2021; 419:126360. [PMID: 34175702 DOI: 10.1016/j.jhazmat.2021.126360] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/05/2021] [Accepted: 06/05/2021] [Indexed: 06/13/2023]
Abstract
Herein, we reported the design and fabrication of polyoxometalates coupling metal-organic framework (POM@MOF) hybrids derived hierarchical hollow Mo/Co bimetal oxides nanocages (Mo/Co HHBONs) for the peroxymonosulfate (PMS) activation to degrade levofloxacin (Lev). The Mo/Co HHBONs are hollow nanocages with high specific-surface areas and hierarchical micropores, mesopores, and macropores. In addition to compositional modulation, polyoxometalate (H3PMo12O40·nH2O) exhibited striking effect on the textural properties of Mo/Co HHBONs. The Mo/Co HHBONs had outstanding catalytic activity with first order-kinetics that were 6 - 10 times higher those previously reported. They exhibited good adaptability over a pH range of 3 - 11, as well as excellent universality and reusability. By altering the surface porosity, electronic structure, and oxygen vacancies of Co3O4, hetero-metal Mo doping induced Mo/Co HHBONs significantly promote the generation of reactive oxygen species, including •OH, SO4•-, O2•-, and 1O2. Density functional theory indicated that Mo/Co HHBONs had better adsorption, enhanced electron-transfer abilities, and a longer O-O bond length than did Co3O4, for improved catalytic reactivity. This research provides a new strategy to design the POM@MOF hybrids derived hierarchical hollow nanocages with highly PMS activating capacity for the removal of antibiotics and other refractory contaminants.
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Affiliation(s)
- Xinlu Yang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xinyu Xie
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Siqi Li
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Wenxuan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xiaodan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Yuming Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
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Gao M, Li S, Zou H, Wen F, Cai A, Zhu R, Tian W, Shi D, Chai H, Gu L. Aged landfill leachate enhances anaerobic digestion of waste activated sludge. J Environ Manage 2021; 293:112853. [PMID: 34044237 DOI: 10.1016/j.jenvman.2021.112853] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 05/08/2021] [Accepted: 05/18/2021] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion (AD) is considered as a sustainable pathway to recover energy from organic wastes, but the digestive efficiency for waste activated sludge (WAS) is not as expected due to the limitations in WAS hydrolysis. This study proposes an effective strategy to simultaneously treat WAS and landfill leachate, aiming to promote WAS hydrolysis and enhance organics converting to methane. The effects of landfill leachate on the four stages (i.e., solubilization, hydrolysis, acidogenesis, and methanogenesis) of AD of WAS, as well as the effect mechanisms were investigated. Results showed that adding appropriate amounts of landfill leachate could promote the steps of solubilization, hydrolysis and acidogenesis of WAS, but had no-effect on methanogenesis. The hydrolysis and acidogenesis efficiency in the leachate added digesters were 2.0%-8.4% and 35.2%-72.7% higher than the control digester. Mechanism studies indicated that humic acid (HA) contained in the leachate was conducive to the processes of both hydrolysis and acidogenesis, but detrimental to the methanogenesis. Effects of heavy metals (HMs) on AD of WAS was also dose-dependent. Digestive performance was inhibited by excessive HMs but promoted by moderate dosages. Humic acid and metal ions tend to interact to form complexes, and thus relieve their each inhibition effects. It is also found that the stability of sludge flocs was reduced by the leachate through reducing both apparent activation energy (AAE) and median particle size (MPS) of the sludge. Microbial community and diversity results revealed that the relative abundance of microbes responsible for hydrolysis and acidogenesis increased when landfill leachate was present. This research provides a more technically and economically feasible approach to co-treating and co-utilizing WAS and landfill leachate.
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Affiliation(s)
- Meng Gao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Siqi Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Huijing Zou
- Hunan Architectural Design Institute Co., Ltd, Hunan, 410125, PR China
| | - Fushan Wen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Anrong Cai
- Chongqing Yuxi Water Co., Ltd, Chongqing, 400045, PR China
| | - Ruilin Zhu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Wenjing Tian
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Dezhi Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China.
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Liu Y, Zheng Z, Deng H, Ren Q, Zhou Z, Zhao C, Chai H. SYNTHESIS AND CHARACTERIZATION OF A NEW COMPOUND 4-(2-CHLOROBENZYL)IMIDAZO[1,2-a] QUINAZOLIN-5(4H)-ONE: DFT STUDY, CRYSTAL STRUCTURE, MEP, AND HOMO–LUMO VALUES. J STRUCT CHEM+ 2021. [DOI: 10.1134/s0022476621080163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Chen Y, Jiang Q, Zhu R, Shi J, Chai H, Li L, Ai H, Shi D, He Q, Gu L. Effects of green waste addition on waste activated sludge and fat, oil and grease co-digestion in mesophilic batch digester. Environ Technol 2021; 42:2870-2884. [PMID: 31941413 DOI: 10.1080/09593330.2020.1717641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 01/11/2020] [Indexed: 06/10/2023]
Abstract
Anaerobic digestion (AD) is regarded as an effective method to treat waste activated sludge (WAS) and fat, oil and grease (FOG). Co-digestion of WAS/FOG could promote the methane yield but it will cause acid and salinity inhibition. Green waste (GW) was added into the digesters, and its effects on co-digestion of WAS and FOG in the mesophilic batch digester were investigated. Digestive performances (such as hydrolysis, acidogenesis and methanogenesis) were studied emphatically. The results showed that digester L6 (WAS:FOG:GW = 1:2:1, VS basis) presented the highest specific methane yield (SMY, 341.5 mL/g VS). The results of kinetics study verified that there was a slower hydrolysis rate when GW was applied as a co-substrate, which could reduce the potential of acid inhibition. Volatile fatty acid (VFA) and electrical conductivity analysis showed that GW addition could keep moderate VFA concentrations and alleviate the negative effects of high-salinity substrates on the digestive systems. The microbial community and diversity analysis proved that GW addition was beneficial to keep the balance of hydrolytic bacteria, acidogens and acetogens. The results of this study indicated that GW addition could enhance the energy recovery and system stability in the WAS/FOG co-digestive system.
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Affiliation(s)
- Yongdong Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Qin Jiang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Ruilin Zhu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Jinghua Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Li Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Hainan Ai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Dezhi Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, People's Republic of China
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Yang Z, Huang P, Chen J, Chen Y, Gao T, Chai H, Zhao C. SYNTHESIS, CRYSTAL STRUCTURE, AND DFT STUDY OF 1-(2-BROMOBENZYL)-4-(4,4,5,5-TETRAMETHYL-1,3,2-DIOXABOROLAN-2-YL)-1H-PYRAZOLE. J STRUCT CHEM+ 2021. [DOI: 10.1134/s0022476621060123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Gao M, Zou H, Tian W, Shi D, Chai H, Gu L, He Q, Tang WZ. Co-digestive performance of food waste and hydrothermal pretreated corn cob. Sci Total Environ 2021; 768:144448. [PMID: 33434805 DOI: 10.1016/j.scitotenv.2020.144448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/03/2020] [Accepted: 12/05/2020] [Indexed: 06/12/2023]
Abstract
Anaerobic co-digestion of lignocellulosic biomass and food waste (FW) has been extensively applied. However, whether hydrothermal pretreatment (HTP) of lignocellulosic biomass can enhance the performance in co-digestion deserves further investigation. In this study, corn cob (CC) was adopted as a typical lignocellulosic biomass for co-digestion with FW at different VS ratios of 1:3 (S1-S4) and 1:6 (S5-S8), attempting to evaluate the effect of HTP of CC at different temperature gradients (125, 150 and 175 °C) on the co-digestion performance. The emphasis was placed on hydrolysis, acidification and methanogenesis for different feedstock conditions. Results illustrated that the HTP had a certain destroying effect on the lignocellulose structure in CC and the crystallinity of cellulose decreased, significantly facilitating its co-digestion with FW. For FW/CC co-digestion at the VS ratio of 1:3, the S3 group (CC was pretreated at 150 °C) reached the maximum cumulative biogas yield (CBY) of 4660 mL and the maximum specific methane yield (SMY) of 316.9 mL/g·VS. Moreover, at 1:6, S7 group (pretreated at 150 °C) exhibited the optimal CBY of 4100 mL while achieving the SMY of 277.6 mL/g·VS among the digesters, indicating that the co-digestion of pretreated CC and FW could achieve higher methane production, and 150 °C refers to the optimal pretreatment temperature. Moreover, the peak values of the accumulated VFAs in digesters S1-S4 (2000-3000 mg/L) is higher than that in digesters S5-S8 (800-1500 mg/L). As suggested from microbial community and diversity date, the HTP expedited the enrichment of system hydrolyzing and acidogenic bacteria. These results are significant and provide certain guidance for optimizing the co-digestion of FW and CC in actual engineering.
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Affiliation(s)
- Meng Gao
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Huijing Zou
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Wenjing Tian
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Dezhi Shi
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Hongxiang Chai
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Li Gu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China.
| | - Qiang He
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Walter Z Tang
- Environmental and Water Resources Engineering, Department of Civil and Environmental Engineering, Florida International University, 10555 W. Flagler Street, EC 3680, Miami, FL 33174, USA
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Wang H, Liu J, Yao J, He Q, Ma J, Chai H, Liu C, Hu X, Chen Y, Zou Y, Xiong J, Huangfu X. Transport of Tl(I) in water-saturated porous media: Role of carbonate, phosphate and macromolecular organic matter. Water Res 2020; 186:116325. [PMID: 32846385 DOI: 10.1016/j.watres.2020.116325] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
Understanding the transport behaviors of thallium (Tl) in porous media is of considerable interest for both natural soils and artificial filtration removal of Tl. In this context, the transport behaviors of Tl(I) in water-saturated sand columns under different conditions were systematically investigated. It was found that, in addition to the effects of pH and ionic strength (IS), the transport of Tl(I) depended on the carbonate, phosphate and macromolecular organic matter as well. Tl(I) broken the columns more difficultly under higher pH and lower IS conditions. Moreover, the adsorption of carbonate and phosphate on sand surfaces may increase the retention of Tl(I) in columns. As for macromolecular organic matter, humic acid (HA) facilitated Tl(I) transport, especially under neutral and alkaline conditions (7.0 and 9.8), which was possibly associated with Tl-complexes formation and competed adsorption between Tl(I) and HA. However, bovine serum albumin (BSA) impeded Tl(I) transport for the reason that deposited BSA might provide more adsorption sites for Tl(I), though Tl(I) had a slight effect on BSA transport. In order to evaluate the mechanisms of transport, a dual-sites non-equilibrium model was applied to fit the breakthrough curves of Tl(I). Retardation factor (R) values of individual Tl(I) transport from model calculations were found to be higher than that of Tl(I) transport with HA and lower than that of Tl(I) transport with BSA. The fraction of instantaneous sorption sites (β) was found to decrease with increasing pH, implying nonequilibrium sorption is a main sorption mechanism of Tl(I) with pH increasing. The fundamental data obtained herein demonstrated that carbonate, phosphate and macromolecular organic matter significantly influenced the Tl(I) migration and could lead to the leaking or bindings of Tl(I) at Tl-occurring sites.
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Affiliation(s)
- Hainan Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Juchao Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Jinni Yao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Caihong Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Xuebin Hu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Yao Chen
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Yijie Zou
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Jiaming Xiong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China
| | - Xiaoliu Huangfu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, China.
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Xia F, Yang H, Li L, Ren Y, Shi D, Chai H, Ai H, He Q, Gu L. Enhanced nitrate adsorption by using cetyltrimethylammonium chloride pre-loaded activated carbon. Environ Technol 2020; 41:3562-3572. [PMID: 31050606 DOI: 10.1080/09593330.2019.1615133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 03/20/2019] [Indexed: 06/09/2023]
Abstract
This paper used cetyltrimethylammonium chloride (CTAC) pre-loaded activated carbon (AC) to research nitrate adsorption. Effects of various parameters such as AC types, AC dosage as well as initial pH were studied. The results indicated that the ACs modified by CTAC can get higher nitrate removal. Even pH is neutral and basic, an accepted removal about 2.5 mg/g can be observed. The more CTAC pre-loaded on the AC surface, the higher nitrate adsorption capacity can be obtained. pH is regarded as a key factor affecting interactions between adsorbent and adsorbate, and the results confirmed that the nitrate adsorption on modified AC decreases gradually with the growth of initial pH. Besides, the acidic pH condition is much favoured for adsorption while the results gained a nitrate adsorption about 4.28 mg/g at pH = 3 condition. Sorption mechanism of nitrate on CTAC modified AC was investigated through two kinetic modellings including pseudo-second-order and Weber and Morris intra-particle diffusion model. The results imply that the generalized kinetic models tally well with experimental data. Additionally, interference of co-existing anions is examined, and the results showed that higher co-anions concentration would bring a heavier depression of the nitrate uptake due to its competing for adsorption sites.
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Affiliation(s)
- Fan Xia
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Haifeng Yang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Li Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Yang Ren
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Dezhi Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Hainan Ai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, People's Republic of China
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Xiang Y, Shao Z, Chai H, Ji F, He Q. Functional microorganisms and enzymes related nitrogen cycle in the biofilm performing simultaneous nitrification and denitrification. Bioresour Technol 2020; 314:123697. [PMID: 32593105 DOI: 10.1016/j.biortech.2020.123697] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/11/2020] [Accepted: 06/13/2020] [Indexed: 06/11/2023]
Abstract
Simultaneous nitrification and denitrification (SND) is a potential energy-saving process in wastewater treatment while the nitrogen removal mechanism is still unclear due to the lack of information about the functional microbes and enzymes. Sequencing batch biofilm reactors were implemented to achieve efficient SND. Eight nitrogen removal related microorganisms out of the top abundant 20 microbial community and reference species were used to construct a phylogenetic tree. Functional enzymes and modules analysis were investigated to reveal the SND pathway: in the aerobic part of the biofilm, ammonia oxidation was catalyzed by complete ammonia oxidizers while in the inner anoxic part, denitrification, dissimilatory nitrate reduction (DNRA) and nitrogen fixation (NF) cooperated to stimulate nitrate removal. These results provide a practical aeration control strategy to achieve SND and indicate that DNRA and NF are important nitrogen removal pathways that should not be ignored in the SND mechanism.
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Affiliation(s)
- Yu Xiang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China.
| | - Fangying Ji
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
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Yang Y, Lu H, Shao Z, Liu S, Zhang Y, Jiang D, Gu L, He Q, Chai H. Electron buffer formation through coupling thiosulfate-dependent denitratation with anammox in a single-stage sequencing batch reactor. Bioresour Technol 2020; 312:123560. [PMID: 32473471 DOI: 10.1016/j.biortech.2020.123560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/15/2020] [Accepted: 05/17/2020] [Indexed: 06/11/2023]
Abstract
The combination of thiosulfate-dependent denitratation and anammox in a single-stage reactor provides a feasible way to improve total nitrogen removal. The molar ratios of NH4+/NO3- and S2O32-/NO3- were confirmed to be two key factors affecting the reactor performance. The optimal total nitrogen removal efficiency of 99.4% was achieved at NH4+/NO3- of 0.75 and S2O32-/NO3- of 0.85. The multiple thiosulfate oxidation pathways contribute to electron buffers generated in the system. A novel isotope labeling method using 15N was applied to reveal N transformation pathways and a 3-step model was proposed. The nitrate was first converted to nitrite or nitric oxide (NO) by sulfur-oxidizing bacteria. In the second step, both nitrite and NO were utilized by anammox bacteria. Finally, the nitrate generated from anammox could be removed using sulfur deposits as electron donors. The findings provide a potential solution for mainstream nitrogen removal.
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Affiliation(s)
- Yan Yang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400045, China
| | - Hui Lu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China
| | - Zhiyu Shao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400045, China
| | - Shiyi Liu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400045, China
| | - Yuxin Zhang
- College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China
| | - Debin Jiang
- College of Environment and Resources, Chongqing Technology and Business University, Chongqing 400067, China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400045, China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400045, China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400045, China.
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Li W, Li S, Tang Y, Yang X, Zhang W, Zhang X, Chai H, Huang Y. Highly efficient activation of peroxymonosulfate by cobalt sulfide hollow nanospheres for fast ciprofloxacin degradation. J Hazard Mater 2020; 389:121856. [PMID: 31911017 DOI: 10.1016/j.jhazmat.2019.121856] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/06/2019] [Accepted: 12/08/2019] [Indexed: 06/10/2023]
Abstract
We reported a facile preparation of CoS2, Co3S4, and Co9S8 hollow nanospheres (HNSs) and their use as peroxymonosulfate (PMS) activators for ciprofloxacin (CIP) degradation. The CIP degradation efficiency follows the order of CoS2 > Co3S4 > Co9S8. The Co2+ is proved to be active site for PMS activation and reactive oxygen species generation. The effect of operating parameters on performance of CoS2 HNSs/PMS system was explored. CoS2 HNSs exhibited highly catalytic activity in a wide pH range of 3 - 10. Complete removal of 10 mg/L CIP was achieved by CoS2 HNSs in 3 min at initial pH of 8.0 with 62.6% CIP mineralization. Three other organic pollutants (rhodamine B, methylene blue and tetracycline) were also degraded to evaluate the universality of the CoS2 HNSs/PMS system. The catalytic performance dropped in the presence of chloride, phosphate, nitrate ions and humic acid. Above 97% CIP removal was achieved even in the sixth run. The degradation pathway of CIP was proposed based on HPLC-MS/MS analysis of CIP intermediates, and two new intermediates, namely, C15H18O4N3F (m/z 323) and C29H31O4N6F (m/z 546), were identified for the first time. Both OH and SO4- were generated and the latter played a key role in CIP degradation.
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Affiliation(s)
- Wenqian Li
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Siqi Li
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Yue Tang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xinlu Yang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Wenxuan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xiaodan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Yuming Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
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Tang Y, Chen Q, Li W, Xie X, Zhang W, Zhang X, Chai H, Huang Y. Engineering magnetic N-doped porous carbon with super-high ciprofloxacin adsorption capacity and wide pH adaptability. J Hazard Mater 2020; 388:122059. [PMID: 31951994 DOI: 10.1016/j.jhazmat.2020.122059] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 06/10/2023]
Abstract
We report a high performance magnetic N-doped nanoporous carbon (MNPC) adsorbent synthesized by a simple single-step pyrolysis protocol. Grinding the mixture of ZnO nanoparticles, cobalt hydroxide and 2-methylimidazole produced Zn/Co-ZIFs that were converted into MNPC following subsequent pyrolysis in N2 atmosphere. The optimized MNPC-700-0.4 adsorbent, obtained at 700 °C with Co/(Zn + Co) molar ratio of 0.4, is featured with super-high ciprofloxacin (CIP) adsorption capacity of 1563.7 mg g-1 at 25 °C, fast adsorption dynamics (1.5 h of adsorption equilibrium time), wide pH adaptability (almost unchanged CIP adsorption capacity in pH 4-10), and good magnetic property. The magnetic property and CIP adsorption performance can be easily regulated by modulating the molar ratio of Co/(Zn + Co) and the pyrolysis temperature. The optimal MNPC-700-0.4 was chosen to explore adsorption kinetics and isotherm. The effects of pH, ionic strength and humic acid on CIP adsorption were investigated. CIP adsorption obeyed pseudo-second-order kinetics and well fitted the Langmuir adsorption model. The favorable textural properties (high surface area and pore volume), riched nitrogen structure and large amounts of defects endow the MNPC-700-0.4 lots of sites for CIP adsorption. The CIP adsorption onto MNPC-700-0.4 was mainly controlled by the electrostatic interaction, hydrophobic interaction, π-π stacking and hydrogen bond.
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Affiliation(s)
- Yue Tang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Qiumeng Chen
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Wenqian Li
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xinyu Xie
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Wenxuan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xiaodan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Yuming Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
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Liang C, Tang Y, Zhang X, Chai H, Huang Y, Feng P. ZIF-mediated N-doped hollow porous carbon as a high performance adsorbent for tetracycline removal from water with wide pH range. Environ Res 2020; 182:109059. [PMID: 31884191 DOI: 10.1016/j.envres.2019.109059] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 12/08/2019] [Accepted: 12/17/2019] [Indexed: 06/10/2023]
Abstract
The N-doped porous carbon (NPC) and N-doped hollow porous carbons (NHPC-1 and NHPC-2) were fabricated using ZIF-8 and its composites (resorcinol and formaldehyde coated ZIF-8, ZIF-8@RF and tannic acid coated ZIF-8, ZIF-8@TA) as precursors via high-temperature pyrolysis and their applications for removing tetracycline (TC) from water were investigated. The various technologies, including SEM, TEM, FT-IR, Raman, N2 adsorption-desorption, XRD and XPS were used to characterize the morphology, textual property, phase and microstructure of three porous carbon materials. The adsorption isotherms and kinetics of TC on three porous carbon materials were fitted well with Langmuir model and pseudo-2nd order model, respectively. In terms of the Langmuir model, the maximum TC adsorption capacities on the NPC, NHPC-1 and NHPC-2 were 180.2, 284.9 and 518.1 mg g-1 at 25 °C, respectively. The excellent performance of NHPC-2 for TC removal is mainly attributed to the suitable pore size distribution and pore volume, high nitrogen contents and large amounts of defects. High TC adsorption was achieved in 3-10 pH range and hardly affected by humic acid. TC adsorption on NHPC-2 is spontaneous and endothermic process. The NHPC-2 kept excellent TC adsorption capacity even after eight cycles, showing its good repeatability. Our result indicates that the MOF-mediated N-doped hollow porous carbon is promising for the TC removal from aqueous media.
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Affiliation(s)
- Chunhong Liang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China
| | - Yue Tang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Xiaodan Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
| | - Yuming Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China.
| | - Ping Feng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China.
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Qin Y, Long D, Zhu X, Zhou Z, Chai H, Zhao C. Synthesis, Crystal Structure, and DFT Study of a New Compound 6-(2-Fluorophenyl)-N-(p-Tolyl)Imidazo[1,2-A]Pyridine-2-Carboxamide. J STRUCT CHEM+ 2020. [DOI: 10.1134/s0022476619120072] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zhao P, Lin Z, Wang Y, Chai H, Li Y, He L, Zhou J. Facilitating effects of plant hormones on biomass production and nutrients removal by Tetraselmis cordiformis for advanced sewage treatment and its mechanism. Sci Total Environ 2019; 693:133650. [PMID: 31377356 DOI: 10.1016/j.scitotenv.2019.133650] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 07/11/2019] [Accepted: 07/27/2019] [Indexed: 06/10/2023]
Abstract
Advanced sewage treatment by microalgae is regarded as a promising method for addressing eutrophication. To improve sewage treatment, three kinds of plant hormones including auxin (indole-3-acetic acid, IAA), cytokinin (Zeatin), and brassinosteroid, were chosen to measure the influence of plant hormones on nitrogen and phosphorus removal by Tetraselmis cordiformis and to analyze their mechanisms, including photosynthesis, nutrient metabolism, and gene transcription. The results indicated that the maximal removal efficiencies of total nitrogen and phosphate by T. cordiformis were elevated by the plant hormones by 184.3% and 53.2%, respectively. The chlorophyll a content was increased by 1.1 times by the plant hormones in comparison with the control. Moreover, after being stimulated by plant hormones, the activities of nitrate reductase (NR) and glutamine synthetase (GS) increased by 90.4% and 82.1%, respectively, in comparison with the control. Supplementation with plant hormones also significantly elevated the mRNA expression level of GS-related gene by 30.9%. This study demonstrated that plant hormones could significantly promote the nutrient removal of microalgae for sewage treatment in artificial laboratory conditions and provided theoretical support for its further practical full-scale application under variable conditions.
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Affiliation(s)
- Pengcheng Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Ziyuan Lin
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yingmu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yancheng Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Lei He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Jian Zhou
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China.
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Chai H, Chen Z, Shao Z, Deng S, Li L, Xiang Y, Li L, Hu X, He Q. Long-term pollutant removal performance and mitigation of rainwater quality deterioration with ceramsite and Cyperus alternifolius in mountainous cities of China. Environ Sci Pollut Res Int 2019; 26:32993-33003. [PMID: 31512121 DOI: 10.1007/s11356-019-06328-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
Rainwater harvesting brings various desired environmental and social benefits in urban development. Tanks in rainwater harvesting systems need low-maintenance and low-cost approaches to manage water quality, especially for scattered small rainwater tanks associated with complex terrains in mountainous cities. Four rain barrels were set up to store roof runoff at the campus of Chongqing University, Chongqing, China. Barrel 1 (B1) and barrel 2 (B2) stored the first-flush water and the roof runoff with first-flush water diverted, respectively, while barrel 3 (B3) was loaded with a biological ceramsite and barrel 4 (B4) used biological ceramsite as a substrate media and planted with Cyperus alternifolius (C. alternifolius) to treat the first-flush water. The performances of the rain barrels were evaluated as well as the variations in water quality parameters were examined. The removal efficiency of B3 was 48.2%, 76.0%, 44.3%, and 24.6% for COD, NH4+-N, TN, and TP, respectively, while B4 had removal efficiencies of 93.4%, 71.0%, 75.0%, and 76.5% for COD, NH4+-N, TN, and TP, respectively. B4 had BOD, NH4+-N, TN, and TP concentrations within the class III Chinese Standard requirement after a storage period of about 240 days. Furthermore, the turbidity in B4 kept dropping. Thus, B4 is a more promising alternative for water quality management in mountainous cities of China.
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Affiliation(s)
- Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Zi Chen
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Siping Deng
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Liang Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Yu Xiang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Li Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Xuebin Hu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
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Chen Y, Zhao Z, Zou H, Yang H, Sun T, Li M, Chai H, Li L, Ai H, Shi D, He Q, Gu L. Digestive performance of sludge with different crop straws in mesophilic anaerobic digestion. Bioresour Technol 2019; 289:121595. [PMID: 31203179 DOI: 10.1016/j.biortech.2019.121595] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/27/2019] [Accepted: 05/30/2019] [Indexed: 06/09/2023]
Abstract
This study evaluated the digestive performance of excess sludge and different crop straws. Methane production, hydrolytic and acidogenic performance of different substrates were specially focused. Results showed that wheat straw presented the highest experimental biochemical methane potential (BMP, 462.5 mL/g VSremoval). Corn cob-added digester obtained the highest VS removal (68.8%) and the lowest methane content due to its high hemicellulose content. Kinetic studies showed that addition of crop straws could shorten the lag phase and accelerate the hydrolysis of substrates. 3DEEM results indicated that lignocellulosic compositions play important roles in sludge hydrolysis, while FE-SEM analysis showed that the lignocellulosic textures of different crop straws determine their hydrolytic performances. Microbial community and diversity results showed that the crop straws in sludge provided abundant nutrients and their unique structures supplied attachment points for microorganisms, which ensured the efficient operation of digestive process.
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Affiliation(s)
- Yongdong Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Ziyan Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Huijing Zou
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Haifeng Yang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Tong Sun
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China; General Research Institute of Architecture & Planning Design Co. LTD., Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Mingxing Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China; General Research Institute of Architecture & Planning Design Co. LTD., Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Li Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Hainan Ai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Dezhi Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China.
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Chai H, Deng S, Zhou X, Su C, Xiang Y, Yang Y, Shao Z, Gu L, Xu X, Ji F, He Q. Nitrous oxide emission mitigation during low-carbon source wastewater treatment: effect of external carbon source supply strategy. Environ Sci Pollut Res Int 2019; 26:23095-23107. [PMID: 31183761 DOI: 10.1007/s11356-019-05516-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 05/17/2019] [Indexed: 06/09/2023]
Abstract
Nitrous oxide (N2O) generated during biological nitrogen removal in wastewater treatment processes has contributed an important proportion to the global warming effect. To evaluate the possibility of N2O emission mitigating by changing carbon source supply strategies, nitrogen transformation characteristics and N2O emissions with methanol one-time dosing and step dosing were investigated. Two sets of laboratory-scale sequencing batch biofilm reactors (SBBRs) were conducted to treat real domestic wastewater with low carbon source. The results revealed that reactors with methanol step dosing showed a lower N2O emission of 0.0402 ± 0.0016 mg/(L·h), together with a higher total nitrogen and ammonia nitrogen removal efficiencies of 83.30% ± 1.21 and 93.45% ± 1.20, respectively. While N2O emission from conventional one-time dosing reactors was 0.0741 ± 0.0025 mg/(L·h), total nitrogen and ammonia nitrogen removal efficiencies were 75.71% ± 0.54 and 88.45% ± 0.59, respectively. The N2O emission factor of SBBR was reduced from 6.26% ± 0.21 to 3.40% ± 0.14 with methanol step dosing. Moreover, nitrification rates in aerobic phases were reduced, while denitrification rates in anoxic phases were elevated. Hence, carbon source step dosing enhanced nitrogen removal and reduced N2O emission compared with one-time dosing, which is a simply achievable strategy for N2O emission reduction in highly automated systems like wastewater treatment plants.
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Affiliation(s)
- Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Siping Deng
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Xiaoyuan Zhou
- College of Physics, Chongqing University, Chongqing, 401331, People's Republic of China
| | - Chuanrong Su
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Yu Xiang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Yan Yang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Li Gu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Xuan Xu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Fangying Ji
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
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Zhao T, Chen Y, Yu Q, Shi D, Chai H, Li L, Ai H, Gu L, He Q. Enhancement of performance and stability of anaerobic co-digestion of waste activated sludge and kitchen waste by using bentonite. PLoS One 2019; 14:e0218856. [PMID: 31291286 PMCID: PMC6619994 DOI: 10.1371/journal.pone.0218856] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 06/11/2019] [Indexed: 11/18/2022] Open
Abstract
There are large amounts of waste activated sludge (WAS) and kitchen waste (KW) produced every year in China. It has been confirmed that anaerobic co-digestion is an effective method to solve this problem. The targets of the present study were optimizing the digestive performances and clearing of the mechanism of bentonite addition by adding bentonite into digestive system. Group M (WAS: KW = 1:2, based on VS) presented higher cumulative methane yield (CMY), where the CMY increased from 19.8 to 36.3 mL/g VS with the bentonite dosage from 0 to 2 g/g VS. After bentonite addition, the lag phase of every digester presented an obvious decrease from 15.1 to 1.4 d. Furthermore, and the moderating effects on microbial community by bentonite. The addition of bentonite improved methane production, and it can also reduce the lag phase of methane production in co-digestion. What's more, bentonite addition increased the speed of pH recovery from 4.2–4.8 to normal level (7.0–8.0) and thus enhanced the system stability. The conclusion of this study can be used to guide practical engineering.
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Affiliation(s)
- Ting Zhao
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Yongdong Chen
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Qing Yu
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Dezhi Shi
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Li Li
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Hainan Ai
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
- * E-mail:
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, PR China
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Li S, Hu X, Chen Q, Zhang X, Chai H, Huang Y. Introducing bifunctional metal-organic frameworks to the construction of a novel ratiometric fluorescence sensor for screening acid phosphatase activity. Biosens Bioelectron 2019; 137:133-139. [DOI: 10.1016/j.bios.2019.05.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 04/05/2019] [Accepted: 05/04/2019] [Indexed: 12/30/2022]
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Zhao P, Wang Y, Lin Z, Zhou J, Chai H, He Q, Li Y, Wang J. The alleviative effect of exogenous phytohormones on the growth, physiology and gene expression of Tetraselmis cordiformis under high ammonia-nitrogen stress. Bioresour Technol 2019; 282:339-347. [PMID: 30878885 DOI: 10.1016/j.biortech.2019.03.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/06/2019] [Accepted: 03/07/2019] [Indexed: 06/09/2023]
Abstract
In this study, the toxic effect of high ammonia on microalgae Tetraselmis cordiformis and the detoxification of phytohormones were researched. The growth, physiological changes, and gene transcription of T. cordiformis were examined. Malondialdehyde content was increased by 2.12 times compared with the control, suggesting the oxidative damage of T. cordiformis. However, the damaging effect of ammonia stress was significantly alleviated by exogenous phytohormones revealed by photosynthetic activity, antioxidant capacity, and nitrogen metabolism. Compared with cells exposed to 500 mg L-1 ammonia (NH4+-N), phytohormones increased the transcript abundance of photosynthesis-related gene (rbcL) by up to 10.95 times. Besides, after adding phytohormones, maximum activities of the antioxidant enzyme catalase (CAT) and nitrogen metabolism-related enzyme glutamine synthetase (GS) were 2.17 and 6.72 times that of the cells exposed to 500 mg L-1 NH4+-N. This study displayed the toxic mechanism of high ammonia on T. cordiformis, and also proved the detoxification of phytohormones.
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Affiliation(s)
- Pengcheng Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yingmu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Ziyuan Lin
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Jian Zhou
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China.
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yancheng Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Jiale Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
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Chai H, Xiang Y, Chen R, Shao Z, Gu L, Li L, He Q. Enhanced simultaneous nitrification and denitrification in treating low carbon-to-nitrogen ratio wastewater: Treatment performance and nitrogen removal pathway. Bioresour Technol 2019; 280:51-58. [PMID: 30754005 DOI: 10.1016/j.biortech.2019.02.022] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 06/09/2023]
Abstract
Simultaneous nitrification and denitrification (SND) is an energy-saving wastewater treatment process, however, the nitrogen removal pathways are not clear. An enhanced SND sequencing batch biofilm reactor with a SND ratio above 97.3% was built to treat low carbon to nitrogen ratio wastewater. When traditional nitrification was inhibited, ammonia removal efficiency still reached 45% in 8 h while the NO3- and NO2- concentration was less than 3 mg/L and 0.01 mg/L during the complete process, respectively. The pathways that could not be suppressed by the inhibitors (ATU and ClO3-) were stimulated by heterotrophic nitrifiers and aerobic denitrifiers with periplasmic nitrate reductase and contributed 55% of the total removed NH4+ and produced 51% of the emitted N2O. The contributions of different nitrogen removal pathways indicate that the unconventional pathways are important in wastewater treatment system and inhibitors should be carefully used in nitrogen removal pathway assays.
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Affiliation(s)
- Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, PR China.
| | - Yu Xiang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, PR China
| | - Rong Chen
- Xian University Architecture & Technology, Int Sci & Technol Cooperat Ctr Urban Alternat Wat, Key Lab Northwest Water Resource Environm & Ecol, MOE, Engn Technol Res Ctr Wastewater Treatment & R, 13 Yanta Rd, Xian 710055, Shanxi, PR China
| | - Zhiyu Shao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, PR China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, PR China
| | - Li Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, PR China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, PR China
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Li L, Huang J, Hu X, Zhang S, Dai Q, Chai H, Gu L. Activation of sodium percarbonate by vanadium for the degradation of aniline in water: Mechanism and identification of reactive species. Chemosphere 2019; 215:647-656. [PMID: 30347359 DOI: 10.1016/j.chemosphere.2018.10.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 09/29/2018] [Accepted: 10/07/2018] [Indexed: 06/08/2023]
Abstract
Sodium percarbonate (SPC)-based advanced oxidation process has been applied to the wastewater treatment in recent years. In the present study, a novel catalyst utilization of vanadium(V) was investigated for the activation of SPC for aniline degradation. The mechanism of SPC activation by V(IV) was demonstrated, and the major free radicals were identified through scavenging tests and electron paramagnetic resonance (EPR) analysis. The performance of aniline degradation was evaluated in the V(IV)/H2O2 and V(IV)/H2O2/Na2CO3 systems and compared with that of the V(IV)/SPC system. The influences of initial pH and effects of inorganic anions were also studied. The results show that aniline could be decomposed efficiently by SPC activated with V(IV) and the degradation efficiency increased with the increase in V(IV) and SPC dosage. O2-, CO3-, and OH were found to participate in aniline degradation, and O2- and CO3- were confirmed to be the predominant species. The decomposition of aniline was enhanced when equal amount of H2O2 was utilized instead of SPC under acidic condition while a comparative behavior was achieved in the V(IV)/H2O2/Na2CO3 system. Furthermore, aniline degradation was not impacted significantly by the initial pH and addition of Cl-, SO42- and NO3-, while HCO3- led to a betterment of aniline removal. These results indicate that the V(IV)/SPC system is an effective and promising approach for the removal of aniline from water for its feasibility and stability, which achieves eliminating contaminants by another waste.
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Affiliation(s)
- Li Li
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Jun Huang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Xuebin Hu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Sai Zhang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China.
| | - Qin Dai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Li Gu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing University, Chongqing 400045, China
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Chai H, Li W, Shao Z, Li L, He Q. Pollutant removal performance of an integrated system that combines a baffled vertical-flow wetland and a scenic water body. Environ Sci Pollut Res Int 2019; 26:269-281. [PMID: 30392174 DOI: 10.1007/s11356-018-3507-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 10/16/2018] [Indexed: 06/08/2023]
Abstract
Stormwater treatment requires effective control measures and development of low-cost and high-efficiency technologies. An integrated system is developed by combining a baffled vertical-flow constructed wetland (BVFCW) and a scenic water body for stormwater quality control purpose. The objectives of the study are to compare the pollutant removal performance of the full-scale integrated system with four groups of wetland-to-scenic water body area ratios (WSARs) including 1/11, 2/11, 3/11, 4/11 and investigate its treatment efficiency. Results show that the system performs better in the removal of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH4+-N), nitrate-nitrogen (NO3-N), and total phosphorus (TP) at the WSAR of 4/11 than that at 3/11 in sixteen-day operation, while it reaches the highest total nitrogen (TN) removal efficiency of 74.0% at the WSAR of 2/11 due to relatively rich carbon source and high influent TN concentration. The integrated system may prove the most effective COD removal at the WSAR of 4/11 for four-time aerobic/anaerobic alternating conditions, a longer flow path and more time to contact with substrates, although the influent COD is lower than that at 2/11 and 1/11. After sixteen-day operation, BVFCW achieved COD removal rate of 90.3%, NH4+-N removal rate of 85.7%, NO3-N removal rate of 68.6%, and TP removal rate of 52.5% at the WSAR of 4/11. At the WSAR of 1/11, effluent met the Class IV requirements in Chinese standards after one-week operation, while effluent met the Class III requirements under the rest conditions. Since effluent in all WSARs met the standards, WSARs of 1/11 and 2/11 were recommended.
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Affiliation(s)
- Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Wenqian Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Liang Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
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Yang Y, Zhang X, Chen Q, Li S, Chai H, Huang Y. Ultrasound-Assisted Removal of Tetracycline by a Fe/N-C Hybrids/H 2O 2 Fenton-like System. ACS Omega 2018; 3:15870-15878. [PMID: 31458233 PMCID: PMC6644124 DOI: 10.1021/acsomega.8b02581] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 11/08/2018] [Indexed: 05/22/2023]
Abstract
In this work, the degradation of tetracycline (TC) in water by the integrated ultrasound (US)-Fenton process was investigated. For this, a new composite Fe/N-C-x (x is the molar ratio of iron salt Fe(NO3)3·9H2O) catalyst was synthesized through simple carbonization of the mixture of glucose and iron salt Fe(NO3)3·9H2O in the presence of ammonium chloride as the nitrogen source. The resultant catalysts were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometer, and N2 adsorption-desorption, showing a typical graphite porous structure and good magnetic properties. The results indicated that the optimized Fe/N-C-2 catalyst prepared with a mole ratio of glucose/Fe(NO3)3·9H2O/NH4Cl of 5:2:16.8 exhibited the highest TC removal in the Fe/N-C-2/H2O2/US system at a wide pH range from 3.0 to 11.0. At an initial pH of 7.0, TC removal in the Fe/N-C-2/H2O2/TC/US system was 1.83, 18.69, and 28.75 times of that in Fe/N-C-2/TC/H2O2, H2O2/TC/US, and TC/H2O2 systems, showing a positive synergistic action between US and Fe/N-C-2. The effects of catalyst dosage, H2O2 concentration, ultrasonic power, humic acid, and coexisting anions on TC removal were investigated. The preliminary analysis suggested that the Fe-N species and the graphite N dispersed in the carbon matrix are responsible for the efficient catalytic activity. By a simple magnetic separation, the Fe/N-C-2 catalyst was easily recovered and used for the next degradation experiment. Above 88% catalytic ability of Fe/N-C-2 was retained even after six successive runs, suggesting its good reusability. The simple preparation strategy, good magnetic property, and good catalytic ability of the Fe/N-C-2 materials make them promising alternative Fenton-like catalysts for the antibiotics abatement in water.
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Affiliation(s)
- Yu Yang
- Key
Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry
of Education), College of Chemistry and Chemical Engineering, Southwest University,
Bebei, Chongqing 400715, China
| | - Xiaodan Zhang
- Key
Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry
of Education), College of Chemistry and Chemical Engineering, Southwest University,
Bebei, Chongqing 400715, China
| | - Qiumeng Chen
- Key
Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry
of Education), College of Chemistry and Chemical Engineering, Southwest University,
Bebei, Chongqing 400715, China
| | - Siqi Li
- Key
Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry
of Education), College of Chemistry and Chemical Engineering, Southwest University,
Bebei, Chongqing 400715, China
| | - Hongxiang Chai
- Key
Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry
of Education), School of Urban Construction and Environmental Engineering, Chongqing University,
Shapingba, Chongqing 400045, China
- E-mail: . Phone/Fax: +86-23-65127226 (H.C.)
| | - Yuming Huang
- Key
Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry
of Education), College of Chemistry and Chemical Engineering, Southwest University,
Bebei, Chongqing 400715, China
- E-mail: . Phone/Fax: +86-23-68254843 (Y.H.)
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Zou H, Chen Y, Shi J, Zhao T, Yu Q, Yu S, Shi D, Chai H, Gu L, He Q, Ai H. Mesophilic anaerobic co-digestion of residual sludge with different lignocellulosic wastes in the batch digester. Bioresour Technol 2018; 268:371-381. [PMID: 30096645 DOI: 10.1016/j.biortech.2018.07.129] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/24/2018] [Accepted: 07/25/2018] [Indexed: 06/08/2023]
Abstract
Co-digestion of residual sludge (RS) and different lignocellulosic wastes (LWs) including greening waste (GW), decocted Chinese herbs waste (DCHW) and sugarcane bagasse waste (SCBW) was investigated in batch digester. Results show that the application of GW presented the highest specific methane yield (161 mL CH4/g VSadded) due to its high carbohydrate fraction and more balanced C/N ratio in co-substrate mixture. Buswell equation was applied and it is found that biodegradability index (BI) for co-digestion varied from 68.1% to 74.2% (53.0% for RS mono-digestion) depending on the lignin fractions of the LWs. Variation of pH, VFAs, alkalinity and ammonia throughout the digestion were also examined. The addition of LWs induced VFAs formation, as well as their conversion to methane. The higher microbial diversity in RS/LWs co-digestion further confirmed the positive effect of LWs addition in co-digestion.
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Affiliation(s)
- Huijing Zou
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Yongdong Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Jinghua Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Ting Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Qing Yu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Shangke Yu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Dezhi Shi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Hongxiang Chai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China.
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Hainan Ai
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments, Ministry of Education, Institute of Urban Construction and Environmental Engineering, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
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Chai H. THE IMPACT OF UNPAID CAREGIVING ON THE LABOUR MARKET OUTCOMES IN CHINA. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- H Chai
- East China Normal University
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Lee S, Jun H, Joo S, Chai H, Sin N, Almeida D. THE INTERPLAY BETWEEN DAILY POSITIVE EVENTS AND DAILY STRESS SEVERITY ON INFLAMMATION IN ADULTHOOD. Innov Aging 2018. [DOI: 10.1093/geroni/igy031.3709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - H Jun
- . Yonsei University, Seoul, Republic of Korea
| | | | - H Chai
- The Pennsylvania State University
| | - N Sin
- University of British Columbia
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Kang J, Chai H, Sliwinski M, Almeida D. FAMILY SUPPORT MODERATES THE 10-YEAR ASSOCIATION BETWEEN HEART RATE RECOVERY AND COGNITIVE FUNCTION. Innov Aging 2018. [DOI: 10.1093/geroni/igy031.3472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- J Kang
- The Pennsylvania State University
| | - H Chai
- The Pennsylvania State University
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Chai H, Tang Y, Su X, Wang W, Lu H, Shao Z, He Q. Annual variation patterns of the effluent water quality from a green roof and the overall impacts of its structure. Environ Sci Pollut Res Int 2018; 25:30170-30179. [PMID: 30151789 DOI: 10.1007/s11356-018-3039-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/22/2018] [Indexed: 06/08/2023]
Abstract
To explore the optimal combination of vegetation type, substrate type, and substrate thickness in a green roof and the interannual variation patterns of the runoff quality, eight green roof units were constructed in Shenzhen, China. Runoff quality of the eight units was monitored for 3 years (24 rainfall events). The rainfall event mean concentrations (EMC) were used to evaluate runoff quality as well as annual pollutant load. An orthogonal L8(24) experiment was designed to verify the significance of different factors. An optimal level of significant factors was selected to determine the optimal design of green roof. The optimal vegetation was Ophiopogon japonicus. The optimal substrate was modified perlite, while optimal substrate thickness was 200 mm. A three-year interannual variation analysis was performed on the optimal green roof. It was found that the interannual variation of each runoff quality index is different. The concentrations of SS, COD, and NH4+-N in the runoff decreased with years. The concentration of NO3--N increased over time, while TP remained stable. The concentration of TN had certain volatility with no significant interannual variation. Overall, the runoff quality of the green roof improves over time. The optimal green roof's runoff quality in the third year including 11 rainfall events was monitored. Results showed that the effluent quality from the green roof was lower than that of precipitation. The average concentrations of SS, COD, NH4+-N, TN, and TP decreased respectively by 37.85%, 28.89%, 30.25%, 14.52%, and 12.93%, but NO3--N increased by 69.91% comparing to the traditional roof.
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Affiliation(s)
- Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Yue Tang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Xiaojie Su
- Key Laboratory of Dependable Service Computing in Cyber Physical Society (Chongqing University), Ministry of Education, Chongqing, 400044, People's Republic of China
- College of Automation, Chongqing University, Chongqing, 400044, People's Republic of China
| | - Weijie Wang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Hao Lu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
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Hu X, Liu X, Zhang X, Chai H, Huang Y. One-pot synthesis of the CuNCs/ZIF-8 nanocomposites for sensitively detecting H 2 O 2 and screening of oxidase activity. Biosens Bioelectron 2018; 105:65-70. [DOI: 10.1016/j.bios.2018.01.019] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 01/03/2018] [Accepted: 01/09/2018] [Indexed: 11/24/2022]
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Kang W, Chai H, Xiang Y, Chen W, Shao Z, He Q. Assessment of low concentration wastewater treatment operations with dewatered alum sludge-based sequencing batch constructed wetland system. Sci Rep 2017; 7:17497. [PMID: 29235527 PMCID: PMC5727494 DOI: 10.1038/s41598-017-17783-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 11/30/2017] [Indexed: 11/18/2022] Open
Abstract
Competition of volatile fatty acids between anoxic denitrification and anaerobic phosphorus release is prominent. Therefore, low concentration wastewater has restricted effects on nitrogen and phosphorus removal. The purpose of this study is to treat dormitory sewage with a biochemical oxygen demand (BOD) ranging from 50 to 150 mg/L using dewatered alum sludge-based sequencing batch constructed wetland system. Vegetation in the wetland system was chosen to be Phragmites australis. Three parallel cases were carried out to assess impacts due to different hydraulic retention time (HRT) and artificial aeration. The results showed that this system is effective in removing total nitrogen (TN), ammonia nitrogen (NH3-N) and total phosphorus (TP) under different HRT. However, nitrous oxide (N2O) emission poses to be the greatest challenge in the high HRT cases. Artificial aeration could reduce N2O emission but is associated with high operational cost. Results indicate that dewatered alum sludge-based sequencing batch constructed wetland system is a promising bio-measure in the treatment of low concentration wastewater.
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Affiliation(s)
- Wei Kang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, P.R. China.,National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, P.R. China
| | - Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, P.R. China. .,National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, P.R. China.
| | - Yu Xiang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, P.R. China.,National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, P.R. China
| | - Wei Chen
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, P.R. China.,National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, P.R. China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, P.R. China.,National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, P.R. China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, P.R. China.,National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400045, P.R. China
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