1
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Tong Y, Xiang H, Jiang J, Chen W. Interfacial interactions between minerals and organic matter: Mechanisms and characterizations. CHEMOSPHERE 2024; 359:142383. [PMID: 38768785 DOI: 10.1016/j.chemosphere.2024.142383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/15/2024] [Accepted: 05/17/2024] [Indexed: 05/22/2024]
Abstract
Minerals and organic matter are essential components of soil, with minerals acting as the "bone" and organic matter as the "skin". The interfacial interactions between minerals and organic matter result in changes in their chemical composition, structure, functional groups, and physical properties, possessing a significant impact on soil properties, functions, and biogeochemical cycles. Understanding the interfacial interactions of minerals and organic matter is imperative to advance soil remediation technologies and carbon targets. Consequently, there is a growing interest in the physicochemical identification of the interfacial interactions between minerals and organic matter in the academic community. This review provides an overview of the mechanisms underlying these interactions, including adsorption, co-precipitation, occlusion, redox, catalysis and dissolution. Moreover, it surveys various methods and techniques employed to characterize the mineral-organic matter interactions. Specifically, the up-to-date spectroscopic techniques for chemical information and advanced microscopy techniques for physical information are highlighted. The advantages and limitations of each method are also discussed. Finally, we outline future research directions for interfacial interactions and suggests areas for improvement and development of characterization techniques to better understand the mechanisms of mineral-organic matter interactions.
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Affiliation(s)
- Yang Tong
- School of Metallurgy and Environment, Central South University, Changsha, 410083, PR China
| | - Huiqin Xiang
- School of Metallurgy and Environment, Central South University, Changsha, 410083, PR China
| | - Jun Jiang
- School of Metallurgy and Environment, Central South University, Changsha, 410083, PR China
| | - Wei Chen
- School of Metallurgy and Environment, Central South University, Changsha, 410083, PR China.
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2
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Haddad L, Vincent AG, Giesler R, Schleucher J. Small molecules dominate organic phosphorus in NaOH-EDTA extracts of soils as determined by 31P NMR. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 931:172496. [PMID: 38636859 DOI: 10.1016/j.scitotenv.2024.172496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/11/2024] [Accepted: 04/13/2024] [Indexed: 04/20/2024]
Abstract
Understanding the composition of organic phosphorus (P) in soils is relevant to various disciplines, from agricultural sciences to ecology. Despite past efforts, the precise nature of soil organic P remains an enigma, especially that of the orthophosphate monoesters, which dominate 31P NMR spectra of NaOH-EDTA extracts of soils worldwide. The monoester region often exhibits an unidentified, broad background believed to represent high molecular weight (MW) P. We investigated this monoester background using 1D 31P NMR and 2D 1H31P NMR, as well as 31P transverse relaxation (T2) measurements to calculate its intrinsic linewidth and relate it to MW. Analyzing seven soils from different ecosystems, we observed linewidths of 0.5 to 3 Hz for resolved monoester signals and the background, indicating that it consists of many, possibly >100, sharp signals associated with small (<1.5 kDa) organic P molecules. This result was further supported by 2D 1H31P NMR spectra revealing signals not resolved in the 1D spectra. Our findings align with 31P NMR studies detecting background signals in soil-free samples and modern evidence that alkali-soluble soil organic matter consists of self-assemblies of small organic compounds mimicking large molecules.
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Affiliation(s)
- Lenny Haddad
- Department of Medical Biochemistry and Biophysics, Umeå University, 90817 Umeå, Sweden.
| | - Andrea G Vincent
- Escuela de Biología, Universidad de Costa Rica, San José 2060, Costa Rica
| | - Reiner Giesler
- Department of Ecology and Environmental Sciences, Climate Impacts Research Centre, Umeå University, Umeå, Sweden
| | - Jürgen Schleucher
- Department of Medical Biochemistry and Biophysics, Umeå University, 90817 Umeå, Sweden
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3
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Zhang Z, Miller LM, He H, Nadagouda MN, Borch T, O'Shea KE, Dionysiou DD. Molecular insights into the bonding mechanisms between selenium and dissolved organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 915:169429. [PMID: 38123086 DOI: 10.1016/j.scitotenv.2023.169429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/11/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023]
Abstract
Natural organic matter (NOM) plays a critical role in the mobilization and bioavailability of metals and metalloids in the aquatic environment. Selenium (Se), an environmental contaminant of aquatic systems, has drawn increasing attention over the years. While Se is a vital micronutrient to human beings, animals and plants, excess Se intake may pose serious long-term risks. However, the interaction between Se and dissolved organic matter (DOM) remains relatively unexplored, especially the reaction mechanisms and interactions of specific NOM components of certain molecular weight and the corresponding functional group change. Herein, we report an investigation on the interactions between Se and DOM by focusing on the mass distribution profile change of operationally defined molecular weight fractions of humic acid (HA) and fulvic acid (FA). The results showed that across all molecular weights studied, HA fractions were more prone to enhanced aggregation upon introduction of Se into the system. For FA, the presence of Se species results in aggregation, dissociation, and redox reactions with the first two being the major mechanisms. Total organic carbon analysis (TOC), UV-vis spectroscopy (UV-vis), and Orbitrap MS data showed that [10, 30] kDa MW fraction had the largest aromatic decrease (CRAM-like, lignin-like and tannin-like) upon addition of SeO2 via dissociation as the dominant mechanism. Fourier transform infrared spectroscopy (FT-IR) revealed that Se based bridging or chelation of functional groups from individual DOM components through hydrogen bonding in the form of SeO⋯H and possibly Se⋯H and/or attractive electrostatic interactions lead to aggregated DOM1⋯Se⋯DOM2. It was concluded from two-dimensional correlation analyses of excitation emission matrix (EEM) and FT-IR that the preferred Se-binding follows lipid ➔ peptide ➔ tannin ➔ aromatic functionalities. These results provide new understanding of Se interactions with various NOM components in aquatic environments and provide insight for Se assessing health risk and/or treatment of Se contaminated water.
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Affiliation(s)
- Zhe Zhang
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (DCEE), University of Cincinnati, OH 45221, USA
| | - Lance M Miller
- Department of Chemical Engineering, Purdue University, IN 47907, USA
| | - Huan He
- Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Mallikarjuna N Nadagouda
- The U.S. Environmental Protection Agency, ORD, CESER, WID, CMTB, 26 W. Martin Luther King Jr. Drive, Cincinnati, OH 45268, USA
| | - Thomas Borch
- Department of Soil and Crop Sciences and Department of Chemistry, Colorado State University, 1170 Campus Delivery, Fort Collins, CO 80523, USA
| | - Kevin E O'Shea
- Department of Chemistry and Biochemistry, Florida International University, University Park, Miami, FL 33199, USA.
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (DCEE), University of Cincinnati, OH 45221, USA.
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4
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Liu L, Li C, Li H. Long-term microbial community succession and mechanisms of regulation of dissolved organic matter derivation in livestock manure fermentation system. CHEMOSPHERE 2023; 329:138588. [PMID: 37019405 DOI: 10.1016/j.chemosphere.2023.138588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 01/19/2023] [Accepted: 04/01/2023] [Indexed: 05/03/2023]
Abstract
Industrial-scale aerobic fermentation was conducted with livestock manures. Microbial inoculation promoted the growth of Bacillaceae and consolidated its position as the dominant microorganism. Microbial inoculation substantially influenced dissolved organic matter (DOM) derivation and variations of related components in the fermentation system. The relative abundance of humic acid-like substances of DOM increased from 52.19% to 78.27% in microbial inoculation system, resulting in a high humification level. Moreover, lignocellulose degradation and microbial utilization were the important factors influencing DOM content in fermentation systems. The fermentation system was regulated by microbial inoculation, thus achieving a high level of fermentation maturity.
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Affiliation(s)
- Le Liu
- National and Local Joint Engineering Research Center of Biomass Resource Utilization, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Cheng Li
- National and Local Joint Engineering Research Center of Biomass Resource Utilization, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Haixiao Li
- College of Environmental Science and Engineering, Hubei Polytechnic University, Huangshi, 435003, China.
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5
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Cheng K, Zhang L, McKay G. Evaluating the Microheterogeneous Distribution of Photochemically Generated Singlet Oxygen Using Furfuryl Amine. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7568-7577. [PMID: 37130219 PMCID: PMC10853930 DOI: 10.1021/acs.est.3c01726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 05/04/2023]
Abstract
Singlet oxygen (1O2) is an important reactive species in natural waters produced during photolysis of dissolved organic matter (DOM). Prior studies have demonstrated that 1O2 exhibits a microheterogeneous distribution, with [1O2] in the interior of DOM macromolecules ∼30 to 1000-fold greater than in bulk solution. The [1O2] profile for DOM-containing solutions has been determined mainly by the use of hydrophobic probes, which are not commercially available. In this study, we employed a dual-probe method combining the widely used hydrophilic 1O2 probe furfuryl alcohol (FFA) and its structural analogue furfuryl amine (FFAm). FFAm exists mainly as a cation at pH <9 and was therefore hypothesized to have an enhanced local concentration in the near-DOM phase, whereas FFA will be distributed homogeneously. The probe pair was used to quantify apparent [1O2] in DOM samples from different isolation procedures (humic acid, fulvic acid, reverse osmosis) and diverse origins (aquatic and terrestrial) as a function of pH and ionic strength, and all samples studied exhibited enhanced reactivity of FFAm relative to FFA, especially at pH 7 and 8. To quantify the spatial distribution of [1O2], we combined electrostatic models with Latch and McNeill's three-phase distribution model. Modeling results for Suwannee River humic acid (SRHA) yield a surface [1O2] of ∼60 pM, which is ∼96-fold higher than the aqueous-phase [1O2] measured with FFA. This value is in agreement with prior reports that determined 1-3 orders of magnitude higher [1O2] in the DOM phase compared to bulk solution. Overall, this work expands the knowledge base of DOM microheterogeneous photochemistry by showing that diverse DOM isolates exhibit this phenomenon. In addition, the dual-probe approach and electrostatic modeling offer a new way to gain mechanistic insight into the spatial distribution of 1O2 and potentially other photochemically produced reactive intermediates.
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Affiliation(s)
- Kai Cheng
- Zachry
Department of Civil & Environmental Engineering, Texas A&M University, 3131 TAMU, College Station, Texas 77845, United States
| | - Lizhong Zhang
- Department
of Physics, University of California, Santa
Barbara, Santa
Barbara, California 93106, United States
| | - Garrett McKay
- Zachry
Department of Civil & Environmental Engineering, Texas A&M University, 3131 TAMU, College Station, Texas 77845, United States
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Yang F, Fu Q, Antonietti M. Anthropogenic, Carbon-Reinforced Soil as a Living Engineered Material. Chem Rev 2023; 123:2420-2435. [PMID: 36633446 PMCID: PMC9999422 DOI: 10.1021/acs.chemrev.2c00399] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In recent years, the simple synthesis of artificial humic substances (A-HS) by alkaline hydrothermal processing of waste biomass was described. This A-HS was shown to support water and mineral binding, to change soil structure, to avoid fertilizer mineralization, and to support plant growth. Many of the observed macroscopic effects could, however, not be directly related to the minute amounts of A-HS which have been added, and an A-HS stimulated microbiome was found to be the key for understanding. In this review, we describe such anthropogenic soil in the language of the modern concept of living engineered materials and identify natural and artificial HS as the enabler to set up the interactive microbial system along the interfaces of the mineral grains. In that, old chemical concepts as surface activity, redox mediation, and pH buffering are the base of the system structure build-up and the complex self-adaptability of biological systems. The resulting chemical/biological hybrid system has the potential to address world problems as soil fertility, nutrition of a growing world population, and climate change.
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Affiliation(s)
- Fan Yang
- School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China.,Joint Laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China
| | - Qiang Fu
- School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Markus Antonietti
- Department of Colloid Chemistry,Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
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7
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Ye Q, Ding Y, Ding Z, Li R, Shi Z. Unified Modeling Approach for Quantifying the Proton and Metal Binding Ability of Soil Dissolved Organic Matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:831-841. [PMID: 36574384 DOI: 10.1021/acs.est.2c08482] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Soil dissolved organic matter (DOM) is composed of a mass of complex organic compounds in soil solutions and significantly affects a range of (bio)geochemical processes in soil environment. However, how the chemical complexity (i.e., heterogeneity and chemodiversity) of soil DOM molecules affects their proton and metal binding ability remains unclear, which limits our ability for predicting the environmental behavior of DOM and metals. In this study, we developed a unified modeling approach for quantifying the proton and metal binding ability of soil DOM based on Cu titration experiments, Fourier transform ion cyclotron resonance mass spectrometry data, and molecular modeling method. Although soil DOM samples from different regions have enormously heterogeneous and diverse properties, we found that the molecules of soil DOM can be divided into three representative groups according to their Cu binding capacity. Based on the molecular models for individual molecular groups and the relative contributions of each group in each soil DOM, we were able to further develop molecular models for all soil DOM to predict their molecular properties and proton and metal binding ability. Our results will help to develop mechanistic models for predicting the reactivity of soil DOM from various sources.
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Affiliation(s)
- Qianting Ye
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong510006, People's Republic of China
| | - Yang Ding
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong510006, People's Republic of China
| | - Zecong Ding
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong510006, People's Republic of China
| | - Rong Li
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong510006, People's Republic of China
| | - Zhenqing Shi
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong510006, People's Republic of China
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8
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Zhu X, Liu J, Li L, Zhen G, Lu X, Zhang J, Liu H, Zhou Z, Wu Z, Zhang X. Prospects for humic acids treatment and recovery in wastewater: A review. CHEMOSPHERE 2023; 312:137193. [PMID: 36370766 DOI: 10.1016/j.chemosphere.2022.137193] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/26/2022] [Accepted: 11/05/2022] [Indexed: 06/16/2023]
Abstract
Clean water shortages require the reuse of wastewater. The presence of organic substances such as humic acids in wastewater makes the water treatment process more difficult. Humic acids can significantly affect the removal of heavy metals and other such toxins. Humic acids is formed by the decomposition and transformation of animal and plant remains by microorganisms, and naturally exists in soil and water. It is necessary to degrade and remove humic acids from wastewater. As it seriously human health, effective technologies for removing humic acids from wastewater have attracted great interest over the past decades. This study compared existing techniques for removing humic acids from wastewater, as well as their limitations. Physicochemical treatments including filtration and oxidation are basic and key approaches to removing humic acids. Biological treatments including enzyme and fungi-mediated humic acids degradation are economically feasible but require some scalability. In conclusion, the integrated treatment processes are more significant options for the effective removal of humic acids from wastewater. In addition, humic acids have rich utilization values. It can improve the soil, increase crop yields, and promote the removal of pollutants.
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Affiliation(s)
- Xuefeng Zhu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China.
| | - Jiadong Liu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Liang Li
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Guangyin Zhen
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, PR China
| | - Xueqin Lu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, PR China
| | - Jie Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China
| | - Hongbo Liu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China.
| | - Zhen Zhou
- College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai, 200090, PR China
| | - Zhichao Wu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China
| | - Xuedong Zhang
- Department of Environmental Engineering, Faculty of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, PR China.
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9
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Ye Q, Ding Z, Li R, Shi Z. Kinetics of cadmium (Cd), nickel (Ni), and lead (Pb) release from fulvic acid: Role of re-association reactions and quantitative models. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156996. [PMID: 35772564 DOI: 10.1016/j.scitotenv.2022.156996] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 05/30/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
Dissolved organic matter (DOM), a ubiquitous ligand for heavy metals, plays a crucial role in regulating the bioavailability and fate of heavy metals in the environment. However, owing to complex structure and heterogeneity of DOM, it is still challenging to develop kinetics models to predict the rates of heavy metal reactions with DOM. In this study, we investigated the kinetics of Cd, Ni, and Pb release from a typical fulvic acid (FA) under a wide range of experimental conditions using a competing ligand exchange (CLE) method. Among three metals, Cd showed the fastest release from FA while Ni and Pb had slower release rates. Reaction pH also had different impact on the release rates of the three metals, presumably attributed to different proton/metal exchange ratios for the metal ion complexation with FA. We formulated a kinetics model for Cd, Ni, and Pb release from FA by considering metal ions dissociation from FA, re-association of metal ions with FA, and metal ion uptake by the resin in the CLE experiments. The chemical speciation model WHAM 7 was used to predict the local equilibrium status that the kinetic reactions were away from, which help to derive the kinetic parameters based on the equilibrium parameters. For both Cd and Pb, model calculations were sensitive to the re-association rates, especially at high pH, while for Ni, the impact of the re-association rates was less significant. Based on the model parameters obtained in this study, our model simulations have also demonstrated that metal-FA complexes may undergo different rates of dissociation in the environment, affecting the dynamic speciation and transfer of metals to other biological processes. This work has provided a quantitative tool for predicting metal release from DOM, which would be useful for predicting the bioavailability and fate of heavy metals in the environment.
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Affiliation(s)
- Qianting Ye
- School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Zecong Ding
- School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Rong Li
- School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Zhenqing Shi
- School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, Guangdong 510006, People's Republic of China.
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10
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Di Iorio E, Circelli L, Angelico R, Torrent J, Tan W, Colombo C. Environmental implications of interaction between humic substances and iron oxide nanoparticles: A review. CHEMOSPHERE 2022; 303:135172. [PMID: 35649442 DOI: 10.1016/j.chemosphere.2022.135172] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 05/17/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Goethite, hematite, ferrihydrite, and other iron oxides bind through various sorption reactions with humic substances (HS) in soils creating nano-, micro-, and macro-aggregates with a specific nature and stability. Long residence times of soil organic matter (SOM) have been attributed to iron-humic substance (Fe-HS) complexes due to physical protection and chemical stabilization at the organic-mineral interface. Humic acids (HA) and fulvic acids (FA) contain many acidic functional groups that interact with Fe oxides through different mechanisms. Due to the numerous interactions between mineral Fe and natural SOM, much research has led into a better identification and definition of HS. In this review, we first focus on the surface colloidal properties of Fe oxides and their reactivity toward HS. These minerals can be efficiently identified by usual techniques, such as XRD, FTIR spectroscopy, XAS, Mössbauer, diffuse reflectance spectroscopies (DRS), HRTEM, ATM, NanoSIMS. Second, we present the recent state of art regarding the adsorption/precipitation of HS onto iron mineral surfaces and their effects on binding metalloid and trace elements. Finally, we consider future research directions based on recent scientific literature, with particular focus on the ability of Fe nano-particles to increase Fe bioavailability, improve carbon sequestration, reduce greenhouse gas emissions, and decrease the impact of persistent organic and inorganic pollutants. The methodology in this field has rapidly developed over the last decade. However, new procedures to estimate the nature of Fe-HA bonds will be important contributions in clarifying the role of natural iron oxides in soil for carbon stabilization.
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Affiliation(s)
- Erika Di Iorio
- Department of Agricultural, Environmental and Food Sciences (DIAAA), University of Molise, V. De Sanctis, I-86100, Campobasso (CB), Italy.
| | - Luana Circelli
- Department of Agricultural, Environmental and Food Sciences (DIAAA), University of Molise, V. De Sanctis, I-86100, Campobasso (CB), Italy
| | - Ruggero Angelico
- Department of Agricultural, Environmental and Food Sciences (DIAAA), University of Molise, V. De Sanctis, I-86100, Campobasso (CB), Italy
| | - José Torrent
- Departamento de Agronomía, Universidad de Córdoba. Edificio C4, Campus de Rabanales, 14071, Córdoba, Spain
| | - Wenfeng Tan
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Claudio Colombo
- Department of Agricultural, Environmental and Food Sciences (DIAAA), University of Molise, V. De Sanctis, I-86100, Campobasso (CB), Italy
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11
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Menezes O, Kocaman K, Wong S, Rios-Valenciana EE, Baker EJ, Hatt JK, Zhao J, Madeira CL, Krzmarzick MJ, Spain JC, Sierra-Alvarez R, Konstantinidis KT, Field JA. Quinone Moieties Link the Microbial Respiration of Natural Organic Matter to the Chemical Reduction of Diverse Nitroaromatic Compounds. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:9387-9397. [PMID: 35704431 DOI: 10.1021/acs.est.2c01329] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Insensitive munitions compounds (IMCs) are emerging nitroaromatic contaminants developed by the military as safer-to-handle alternatives to conventional explosives. Biotransformation of nitroaromatics via microbial respiration has only been reported for a limited number of substrates. Important soil microorganisms can respire natural organic matter (NOM) by reducing its quinone moieties to hydroquinones. Thus, we investigated the NOM respiration combined with the abiotic reduction of nitroaromatics by the hydroquinones formed. First, we established nitroaromatic concentration ranges that were nontoxic to the quinone respiration. Then, an enrichment culture dominated by Geobacter anodireducens could indirectly reduce a broad array of nitroaromatics by first respiring NOM components or the NOM surrogate anthraquinone-2,6-disulfonate (AQDS). Without quinones, no nitroaromatic tested was reduced except for the IMC 3-nitro-1,2,4-triazol-5-one (NTO). Thus, the quinone respiration expanded the spectrum of nitroaromatics susceptible to transformation. The system functioned with very low quinone concentrations because NOM was recycled by the nitroaromatic reduction. A metatranscriptomic analysis demonstrated that the microorganisms obtained energy from quinone or NTO reduction since respiratory genes were upregulated when AQDS or NTO was the electron acceptor. The results indicated microbial NOM respiration sustained by the nitroaromatic-dependent cycling of quinones. This process can be applied as a nitroaromatic remediation strategy, provided that a quinone pool is available for microorganisms.
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Affiliation(s)
- Osmar Menezes
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Kumru Kocaman
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Stanley Wong
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Erika E Rios-Valenciana
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Eliot J Baker
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Janet K Hatt
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jianshu Zhao
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30318, United States
| | - Camila L Madeira
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Mark J Krzmarzick
- School of Civil and Environmental Engineering, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Jim C Spain
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
- Center for Environmental Diagnostics & Bioremediation, University of West Florida, Pensacola, Florida 32514, United States
| | - Reyes Sierra-Alvarez
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Konstantinos T Konstantinidis
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jim A Field
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
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12
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Lan T, Wu P, Liu Z, Stroet M, Liao J, Chai Z, Mark AE, Liu N, Wang D. Understanding the Effect of pH on the Solubility and Aggregation Extent of Humic Acid in Solution by Combining Simulation and the Experiment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:917-927. [PMID: 34981918 DOI: 10.1021/acs.est.1c05938] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Molecular dynamics (MD) simulations were performed to investigate the dynamics of humic acid (HA) in an aqueous solution and the influence of pH, temperature, and HA concentration. The HA model employed in MD simulations was chosen and validated using experimental chemical composition data and Fourier transform infrared (FTIR) spectra. The simulations showed that the HA molecule has a strong propensity to adopt a compact conformation in water independent of pH, while the aggregation of HA was found to be pH-dependent. At high pH, the ionized HAs assembled into a thread-like structure, maximizing contact with water. At low pH, the neutral HAs formed a droplet-like aggregate, minimizing contact with the solvent. The simulation results are consistent with experimental data from dynamic light scattering (DLS) measurements and transmission electron microscopy (TEM) imaging. This work provides new insight into the folding and aggregation of HA as a function of pH and a molecular-level understanding of the relationship between the acidity and the structure, solubility, and aggregation of HA, with direct implications for HA-based remediation strategies of contaminated sites.
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Affiliation(s)
- Tu Lan
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, P. R. China
| | - Peng Wu
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, P. R. China
| | - Ziyi Liu
- School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Martin Stroet
- School of Chemistry & Molecular Biosciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Jiali Liao
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, P. R. China
| | - Zhifang Chai
- State Key Laboratory of Radiation Medicine and Protection, and School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Suzhou 215123, P. R. China
| | - Alan E Mark
- School of Chemistry & Molecular Biosciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Ning Liu
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, P. R. China
| | - Dongqi Wang
- School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
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13
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Venezia V, Pota G, Silvestri B, Vitiello G, Di Donato P, Landi G, Mollo V, Verrillo M, Cangemi S, Piccolo A, Luciani G. A study on structural evolution of hybrid humic Acids-SiO 2 nanostructures in pure water: Effects on physico-chemical and functional properties. CHEMOSPHERE 2022; 287:131985. [PMID: 34454229 DOI: 10.1016/j.chemosphere.2021.131985] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 08/20/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Humic acids (HA) are considered a promising and inexpensive source for novel multifunctional materials for a huge range of applications. However, aggregation and degradation phenomena in aqueous environment prevent from their full exploitation. A valid strategy to address these issues relies on combining HA moieties at the molecular scale with an inorganic nanostructured component, leading to more stable hybrid nanomaterials with tunable functionalities. Indeed, chemical composition of HA can determine their interactions with the inorganic constituent in the hybrid nanoparticles and consequently affect their overall physico-chemical properties, including their stability and functional properties in aqueous environment. As a fundamental contribution to HA materials-based technology, this study aims at unveiling this aspect. To this purpose, SiO2 nanoparticles have been chosen as a model platform and three different HAs extracted from composted biomasses, manure (HA_Man), artichoke residues (HA_Art) and coffee grounds (HA_Cof), were employed to synthetize hybrid HA-SiO2 nanoparticles through in-situ sol-gel synthesis. Prepared samples were submitted to aging in water to assess their stability. Furthermore, antioxidant properties and physico-chemical properties of both as prepared and aged samples in aqueous environment were assessed through Scanning Electron Microscopy (SEM), N2 physisorption, Simultaneous Thermogravimetric (TGA) and Differential Scanning Calorimetric (DSC) Analysis, Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR), Electron Paramagnetic Resonance (EPR) spectroscopies. The experimental results highlighted that hybrid HA-SiO2 nanostructures acted as dynamic systems which exhibit structural supramolecular reorganization during aging in aqueous environment with marked effects on physico-chemical and functional properties, including improved antioxidant activity. Obtained results enlighten a unique aspect of interactions between HA and inorganic nanoparticles that could be useful to predict their behavior in aqueous environment. Furthermore, the proposed approach traces a technological route for the exploitation of organic biowaste in the design of hybrid nanomaterials, providing a significant contribution to the development of waste to wealth strategies based on humic substances.
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Affiliation(s)
- Virginia Venezia
- Department of Chemical, Materials and Production Engineering, University of Naples "Federico II", p.le V. Tecchio 80, 80125, Naples, Italy.
| | - Giulio Pota
- Department of Chemical, Materials and Production Engineering, University of Naples "Federico II", p.le V. Tecchio 80, 80125, Naples, Italy.
| | - Brigida Silvestri
- Department of Chemical, Materials and Production Engineering, University of Naples "Federico II", p.le V. Tecchio 80, 80125, Naples, Italy.
| | - Giuseppe Vitiello
- Department of Chemical, Materials and Production Engineering, University of Naples "Federico II", p.le V. Tecchio 80, 80125, Naples, Italy; CSGI, Center for Colloids and Surface Science, via della Lastruccia 3, 50019, Florence, Italy.
| | - Paola Di Donato
- Department of Science and Technology, University of Naples "Parthenope", Centro Direzionale Isola C4, 80143, Naples, Italy.
| | - Gianluca Landi
- Institute of Sciences and Technologies for Sustainable Energy and Mobility-CNR, P.le V. Tecchio 80, 80125, Naples, Italy.
| | - Valentina Mollo
- Center for Advanced Biomaterials for Health Care, Istituto Italiano di Tecnologia@CABHC, Largo Barsanti e Matteucci 53, 80125, Naples, Italy.
| | - Mariavittoria Verrillo
- Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l'Ambiente, l'Agroalimentare ed i Nuovi Materiali (CERMANU), University of Naples "Federico II", Via Università 100, 80055, Portici, Italy.
| | - Silvana Cangemi
- Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l'Ambiente, l'Agroalimentare ed i Nuovi Materiali (CERMANU), University of Naples "Federico II", Via Università 100, 80055, Portici, Italy.
| | - Alessandro Piccolo
- Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l'Ambiente, l'Agroalimentare ed i Nuovi Materiali (CERMANU), University of Naples "Federico II", Via Università 100, 80055, Portici, Italy.
| | - Giuseppina Luciani
- Department of Chemical, Materials and Production Engineering, University of Naples "Federico II", p.le V. Tecchio 80, 80125, Naples, Italy.
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14
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Rizzuto S, Jones KC, Zhang H, Baho DL, Leu E, Nizzetto L. Critical assessment of an equilibrium-based method to study the binding of waterborne organic contaminants to natural dissolved organic matter (DOM). CHEMOSPHERE 2021; 285:131524. [PMID: 34329125 DOI: 10.1016/j.chemosphere.2021.131524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/08/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Dissolved organic matter (DOM) can play a major role in determining availability of pollutants to aquatic biota. Equilibrium dialysis is the most commonly used method to assess the interaction between DOM and organic contaminants. However, results obtained through this method can be affected by confounding factors linked to the diffusion of DOM through the membrane or the interaction of DOM and/or the compounds with the membrane itself. In this study, we propose an improved experimental approach, where highly hydrophilic cellulose-ester membranes with small molecular cut-off (100-500 Da) were used to overcome some of these hindrances. The performance of the method to determine the binding of a commonly used moderately hydrophobic herbicide (Isoproturon - ISU) with natural DOM was critically evaluated through a set of quality assurance criteria, across a range of DOM concentrations and pH conditions. DOM trans-membrane diffusion was prevented by the smaller pore size of the dialysis membrane. Good measurement reproducibility, mass balance closure, and successful trans-membrane equilibrium of ISU were obtained. ISU showed relatively low affinity with DOM (log KDOC 1-2 L g-1), which was significantly influenced by varying pH and DOM concentration. An alternative membrane may be needed for higher pH conditions as the greater adsorption effect blurred the observation of trans-membrane equilibrium and confounding mass balance closure. The paper makes recommendations on how to avoid measurement artefacts, while considering criteria for the expected mass distribution of compounds at equilibrium and for sorption onto the membrane and surfaces of the experimental units.
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Affiliation(s)
- Simone Rizzuto
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK
| | - Kevin C Jones
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK.
| | - Hao Zhang
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK.
| | - Didier L Baho
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349, Oslo, Norway
| | - Eva Leu
- Akvaplan-niva, CIENS, Science Park, Gaustadalléen 21, 0349, Oslo, Norway
| | - Luca Nizzetto
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349, Oslo, Norway; RECETOX, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
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15
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Wen Z, Song K, Shang Y, Lyu L, Tao H, Liu G. Natural and anthropogenic impacts on the DOC characteristics in the Yellow River continuum. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 287:117231. [PMID: 34000672 DOI: 10.1016/j.envpol.2021.117231] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 03/24/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
The Yellow River is the second largest river in China. Carbon transport by the Yellow River has significant influence on riverine carbon cycles in Asia. During the wet season, the riverine carbon was mainly found in dissolved form, i.e., dissolved organic carbon (DOC), along the entire course of the river. The distinct spatial variations of DOC concentration were observed at different reaches of the mainstream (p < 0.01), while the highest mean DOC concentration was generally observed at midstream (4.13 ± 0.91 mg/L). Carbon stable isotope analysis δ13C and C: N ratio of DOC, evidenced the sources of DOC in headwater and upstream were primarily the terrestrial plants (94% and 61%), but it was changed to soil organic matter (SOM) in mid- and downstream (36% and 37%), and the contribution of sewage to DOC were also increased to 17% and 18%. In the whole mainstream of the Yellow River, water temperature (WT) had a significant impact on DOC concentration, and it could explain 67% of the DOC variance. However, in a large catchment, the driving mechanisms on the DOC variations in headwaters will not necessarily be those controlling DOC trends in downstream. The study firstly quantified, in headwater and upstream, the natural factors explained as much as 65% and 73% of the DOC variations, respectively. In mid- and downstream areas, DOC was significantly influenced by the amount of wastewater discharged by the industry and the use of chemical fertilizers (p < 0.05). These findings may facilitate a better assessment of global riverine carbon cycling and may help to reveal the importance of the balance between development and environmental sustainability with the changing DOC transport features in the Yellow River due to human disturbances.
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Affiliation(s)
- Zhidan Wen
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Kaishan Song
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; School of Environment and Planning, Liaocheng University, Liaocheng, 252000, China
| | - Yingxin Shang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Lili Lyu
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hui Tao
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ge Liu
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China.
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16
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Murillo-Gelvez J, Di Toro DM, Allen HE, Carbonaro RF, Chiu PC. Reductive Transformation of 3-Nitro-1,2,4-triazol-5-one (NTO) by Leonardite Humic Acid and Anthraquinone-2,6-disulfonate (AQDS). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:12973-12983. [PMID: 34533928 DOI: 10.1021/acs.est.1c03333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
3-Nitro-1,2,4-triazol-5-one (NTO) is a major and the most water-soluble constituent in the insensitive munition formulations IMX-101 and IMX-104. While NTO is known to undergo redox reactions in soils, its reaction with soil humic acid has not been evaluated. We studied NTO reduction by anthraquinone-2,6-disulfonate (AQDS) and Leonardite humic acid (LHA) reduced with dithionite. Both LHA and AQDS reduced NTO to 3-amino-1,2,4-triazol-5-one (ATO), stoichiometrically at alkaline pH and partially (50-60%) at pH ≤ 6.5. Due to NTO and hydroquinone speciation, the pseudo-first-order rate constants (kObs) varied by 3 orders of magnitude from pH 1.5 to 12.5 but remained constant from pH 4 to 10. This distinct pH dependency of kObs suggests that NTO reactivity decreases upon deprotonation and offsets the increasing AQDS reactivity with pH. The reduction of NTO by LHA deviated continuously from first-order behavior for >600 h. The extent of reduction increased with pH and LHA electron content, likely due to greater reactivity of and/or accessibility to hydroquinone groups. Only a fraction of the electrons stored in LHA was utilized for NTO reduction. Electron balance analysis and LHA redox potential profile suggest that the physical conformation of LHA kinetically limited NTO access to hydroquinone groups. This study demonstrates the importance of carbonaceous materials in controlling the environmental fate of NTO.
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Affiliation(s)
- Jimmy Murillo-Gelvez
- Department of Civil and Environmental Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Dominic M Di Toro
- Department of Civil and Environmental Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Herbert E Allen
- Department of Civil and Environmental Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Richard F Carbonaro
- Department of Chemical Engineering, Manhattan College, Riverdale, New York 10471, United States
- Mutch Associates LLC, Ramsey, New Jersey 07446, United States
| | - Pei C Chiu
- Department of Civil and Environmental Engineering, University of Delaware, Newark, Delaware 19716, United States
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17
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Li Q, Bao X, Chen P, Jiao Y, Gu S. Available acid consumption capacity of sediments in six water bodies in the Yangtze River Basin in China. WATER RESEARCH 2021; 203:117565. [PMID: 34418643 DOI: 10.1016/j.watres.2021.117565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 07/27/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Acid-base reactivity is a fundamental property of sediments and is responsible for sediments' multiple roles in aquatic ecosystems. However, little information currently exists about the composition, magnitude, and change of the available acid consumption capacity (AACC) of sediments. To optimize reaction conditions, we developed operational procedures to determine AACC using base titration to recover surplus acid in suspensions. We characterized the sediment AACC of Dianchi Lake (DL), Daduhe River (DR), Tuojiang River (TR), Honghu Lake (HL), Wuhan Donghu Lake (DhL), and Taihu Lake (TL) in the Yangtze River Basin, China. The procedure demonstrated that reacting 40 mL 0.1 M HCl with fresh sediments equivalent to 1.0 g dry weight for 4 h and recovering surplus acid in the suspension by NaOH titration to an endpoint pH of 3.0 could determine sediment AACC. Sediment AACC in the Yangtze River Basin had high regional variability. The mean magnitude of AACC among sites was ranked DL > DR > DhL > TR > HL > TL, which is extremely similar to their geographical location from the upper to lower reaches of the Yangtze River Basin. Qualitative results from acid titration curves showed that more components contributed to AACC in DL, DR, TR, and DhL sediments than to those in HL and TL sediments. The correlation between AACC and the total amount of multivalent cations released indicated that AACC depended significantly on labile acid-soluble minerals that contain multivalent cations (Fe3+, Fe2+, Ca2+, Al3+, Mg2+, and Mn2+) (p < 0.01). Based on the contribution percentages of multivalent cations to AACC, sediment AACC of six water bodies were divided into two types: Ca-Mg dominated (DL, DR, and TR) and Fe-Al dominated (HL, DhL, and TL). We suggest that sediment AACC complexing with pH can contribute to a better description of the acid-base characteristics of sediments.
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Affiliation(s)
- Qingman Li
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, China
| | - Xu Bao
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Peng Chen
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, China; College of Fisheries and Life Sciences, Dalian Ocean University, Dalian 116023, China
| | - Yang Jiao
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, China
| | - Sen Gu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, China.
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18
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Rizzuto S, Baho DL, Jones KC, Zhang H, Leu E, Nizzetto L. Binding of waterborne pharmaceutical and personal care products to natural dissolved organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 784:147208. [PMID: 34088045 DOI: 10.1016/j.scitotenv.2021.147208] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/13/2021] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
Information on how key environmental conditions such as natural dissolved organic matter (DOM) and water pH alter the possible risks posed by pharmaceuticals (PPCPs) is still scarce. In our previous study, the presence of natural DOM at high pH reduced the toxicity of a mix of waterborne PPCPs to algae. DOM-complexation and pH effect on speciation of the more hydrophobic and neutral compounds of the mix was suggested to be driving this behaviour. However, the study design did not allow the verification of this hypothesis. Here, the DOM- PPCPs interaction at different pH was investigated for 6 PPCPs through equilibrium dialysis, under the same conditions of DOM and pH as our previous study. Association with DOM was confirmed for the more hydrophobic PPCPs at high pH. The results suggest the binding was driven by i) the presence of carboxylic groups of PPCPs, ii) high pH shifting the structural configuration of DOM, making it more suited to bind some of the PPCPs. A non-linear change of binding capacity with increasing DOM concentration was also observed among the tested PPCPs.
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Affiliation(s)
- Simone Rizzuto
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Didier L Baho
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden; Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway
| | - Kevin C Jones
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
| | - Hao Zhang
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
| | - Eva Leu
- Akvaplan-niva, CIENS, Science Park, Gaustadalléen 21, 0349 Oslo, Norway
| | - Luca Nizzetto
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway; RECETOX, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic
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19
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Yang F, Tang C, Antonietti M. Natural and artificial humic substances to manage minerals, ions, water, and soil microorganisms. Chem Soc Rev 2021; 50:6221-6239. [PMID: 34027951 DOI: 10.1039/d0cs01363c] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The chemistry of humic substances (HSs) occurs hidden from our sight, but is of key importance to agriculture and the environment, and nowadays even to medicine and technology. HSs are nowadays not only natural, but extracted and engineered, and in the past 20 years such products have been widely used in soil improvement and environment governance. In this review, we collate and summarize the applications and working principles of such HSs in agriculture and environmental ecology, mainly to elaborate the multiple roles of this functional polymer along with physical chemical quantification. Then several of the latest synthesis technologies, including hydrothermal humification technology (HTH), hydrothermal carbonization technology (HTC) and hydrogen peroxide oxidation technology (HOT) are presented, which were introduced to prepare artificial humic substances (A-HSs). The availability of reproducible and tunable synthetic A-HSs is a new chemical tool, and effects such as solubilization of insoluble phosphorus minerals, recovery of phosphorus, improvement of soil fertility for crop growth and reduction of toxicity of typical pollutants, can now be analyzed in detail and quantified. As a result, we can provide an effective chemical technology for utilizing biomass side products ("biowaste") to generate A-HSs of different types, thus realizing improvement in agricultural production and control of environmental pollution by the macro-synthesis of A-HSs-.
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Affiliation(s)
- Fan Yang
- Joint Laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China. and School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Chunyu Tang
- Joint Laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China. and School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Markus Antonietti
- Max Planck Institute of Colloids and Interfaces, Department of Colloid Chemistry, 14476 Potsdam, Germany.
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20
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Tang C, Li Y, Song J, Antonietti M, Yang F. Artificial humic substances improve microbial activity for binding CO 2. iScience 2021; 24:102647. [PMID: 34466779 PMCID: PMC8387571 DOI: 10.1016/j.isci.2021.102647] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/21/2021] [Accepted: 05/20/2021] [Indexed: 12/20/2022] Open
Abstract
Humic substances (HS) are an indicator of fertile soils, but more and more soils keep losing there humic matter. This is mostly due to anthropogenic over-cultivation. Artificial humic acid (A-HA) and artificial fulvic acid were synthesized from agricultural litter, with high similarity to natural HS extracted from soil. These samples were added to black soils, and soil activity and nutrients availability were analyzed. The results demonstrate that the content of dissolved organic matter and total organic carbon (TOC) largely increased. The increase in TOC 28 days after addition of A-HA was 21.4 g/kg. This was much higher than the amount of the added A-HA carbon, which was 0.3 g/kg. As a "secondary" benefit, nutrient availability is increased, promoting the growth of plants. Using high-throughput sequencing we revealed that A-HA strongly supports the growth of photosynthetic Rubrivivax gelatinosus, which induced the carbon sequestration. Thus, application of artificial HS shows potential for biologically amplified carbon sequestration within black soils.
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Affiliation(s)
- Chunyu Tang
- Joint laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China.,School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Yuelei Li
- Joint laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China.,School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Jingpeng Song
- Joint laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China.,School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Markus Antonietti
- Max Planck Institute of Colloids and Interfaces Department of Colloid Chemistry, 14476 Potsdam, Germany
| | - Fan Yang
- Joint laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces (NEAU-MPICI), Harbin 150030, China.,School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
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21
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4D imaging reveals mechanisms of clay-carbon protection and release. Nat Commun 2021; 12:622. [PMID: 33504777 PMCID: PMC7840981 DOI: 10.1038/s41467-020-20798-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/07/2020] [Indexed: 11/09/2022] Open
Abstract
Soil absorbs about 20% of anthropogenic carbon emissions annually, and clay is one of the key carbon-capture materials. Although sorption to clay is widely assumed to strongly retard the microbial decomposition of soil organic matter, enhanced degradation of clay-associated organic carbon has been observed under certain conditions. The conditions in which clay influences microbial decomposition remain uncertain because the mechanisms of clay-organic carbon interactions are not fully understood. Here we reveal the spatiotemporal dynamics of carbon sorption and release within model clay aggregates and the role of enzymatic decomposition by directly imaging a transparent smectite clay on a microfluidic chip. We demonstrate that clay-carbon protection is due to the quasi-irreversible sorption of high molecular-weight sugars within clay aggregates and the exclusion of bacteria from these aggregates. We show that this physically-protected carbon can be enzymatically broken down into fragments that are released into solution. Further, we suggest improvements relevant to soil carbon models.
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22
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Yang W, Zhang T, Han C, Tang N, Yang H, Xue X. Photoenhanced heterogeneous reaction of O 3 with humic acid: Focus on O 3 uptake and changes in the composition and optical property. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 268:115696. [PMID: 33010673 DOI: 10.1016/j.envpol.2020.115696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 09/15/2020] [Accepted: 09/16/2020] [Indexed: 06/11/2023]
Abstract
Heterogeneous photochemical reaction of O3 with humic acid (HA) under simulated sunlight was performed using a flow tube reactor coupled to an O3 analyzer at ambient pressure. It was confirmed that light significantly enhanced the uptake of O3 on HA. The initial uptake coefficient (γi) and the steady-state uptake coefficient (γss) of O3 under irradiation increased by 1.6 and 3.8 times compared to those in the dark, respectively. The γi and γss on HA varied in the range of 0.76-2.77 × 10-5 and 1.50-9.55 × 10-6, respectively, which were dependent on various environmental factors including HA mass, total irradiance, initial O3 concentration, O2 content, temperature, relative humidity (RH) and HA solution pH. Both γi and γss showed linear dependence on the total irradiance (0-2.07 × 1016 photons/(cm2⋅s)) of the light source, and increased with the HA mass (0-3.2 μg/cm2), temperature (278-298 K) and HA solution pH (4.0-9.6). However, they showed negative correlations with the initial O3 concentration and O2 content. The γi remained constant in the RH range of 7%-60%, while γss exhibited the maximum value at RH = 20%. During the ozonization of HA under irradiation, some functional groups were consumed, including CH2, CH3, aromatic CC, OH, CO, COOH and COO-. HA aged by O3 exhibited a decrease in the mass absorption efficiency (MAE) and a small increase in the absorption Ångström exponent between 300 and 600 nm wavelength (AAE300,600), which was ascribed to changes in the composition of HA during the photochemical ozonization process.
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Affiliation(s)
- Wangjin Yang
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
| | - Tingting Zhang
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
| | - Chong Han
- School of Metallurgy, Northeastern University, Shenyang, 110819, China.
| | - Ning Tang
- Institute of Nature and Environmental Technology, Kanazawa University, Kanazawa, 920-1192, Japan
| | - He Yang
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
| | - Xiangxin Xue
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
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23
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Audette Y, Smith DS, Parsons CT, Chen W, Rezanezhad F, Van Cappellen P. Phosphorus binding to soil organic matter via ternary complexes with calcium. CHEMOSPHERE 2020; 260:127624. [PMID: 32683029 DOI: 10.1016/j.chemosphere.2020.127624] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 07/03/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
Soil organic matter (SOM) is known to exert a major control on the mobility and bioavailability of cationic nutrients. However, the role of SOM in the fate of anionic nutrients, especially phosphorus (P), is less well characterized. The objectives of this study were to (1) compare the formation of binary complexes of calcium (Ca) with humic acids (HA) extracted from two contrasting soils, and (2) determine if binary HA-Ca complexes could incorporate P by forming ternary HA-Ca-P complexes. The Ca binding capacities of the HA extracted from an agricultural organic soil (AOS) and a pristine riparian soil (RS) were measured via potentiometric titrations; the formation of ternary complexes was analyzed by size fractionation using MWCO tubes. Proton and Ca binding capacities of RS-HA were higher than AOS-HA, and pH had a weaker effect on Ca binding to RS-HA. These differences are consistent with lower proportions of aromatic groups, and a higher proportion of alkyl groups derived from 13C NMR spectroscopy. Together, the NMR, titration and MWCO data indicate that Ca binds to RS-HA through monodentate complexes and electrostatic attraction that are capable of binding P producing ternary complexes. In contrast, at pH 8.5 Ca forms bidentate complexes with AOS-HA, which do not provide bridging positions to incorporate P. Overall, our results imply that the formation of HA-Ca and HA-Ca-P complexes depend on the structure of the HA, and that complexation to HA may play an important role in the fate of P in terrestrial and aquatic environments.
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Affiliation(s)
- Yuki Audette
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada; School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
| | - D Scott Smith
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - Christopher T Parsons
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada
| | - Weibin Chen
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - Fereidoun Rezanezhad
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada
| | - Philippe Van Cappellen
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada
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24
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Tan W, Liu N, Dang Q, Cui D, Xi B, Yu H. Insights into the removal efficiencies of aged polycyclic aromatic hydrocarbons in humic acids of different soil aggregate fractions by various oxidants. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 264:114678. [PMID: 32375091 DOI: 10.1016/j.envpol.2020.114678] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/05/2020] [Accepted: 04/25/2020] [Indexed: 06/11/2023]
Abstract
Chemically oxidative removal of polycyclic aromatic hydrocarbons (PAHs) in soil is related to their occurrence state. Whether the heterogeneity of natural organic matter has an effect on the occurrence of PAHs in soil and, if there is an effect, on the oxidative removal efficiency of PAHs remains unknown. In this study, the removal efficiencies of 16 priority PAHs aged in humic acids (HAs) of different soil aggregate fractions by various oxidants were investigated by combining soil fractionation and microreaction experiments. Results showed that the accumulations of PAHs in particulate HA (P-HA) and microaggregate occluded HA (MO-HA) mainly occurred in the early period of the aging time frame. In contrast, PAH accumulation in non-aggregated silt and clay associated HA (NASCA-HA) was relatively slow and tended to saturate in the late period of the aging time frame. The cumulative contents of PAHs throughout the entire aging period in MO-HA and NASCA-HA were significantly greater than that in P-HA. The aged PAHs in P-HA and NASCA-HA exhibited the highest and lowest removal efficiencies, respectively. This ranking was mainly governed by the molecular size and polarity of HAs. Sodium persulfate and potassium permanganate had the highest removal efficiencies in total PAHs in HAs, with average efficiencies of 85.8% and 79.1%, respectively, in P-HA. Hydrogen peroxide had the lowest degradation efficiency in PAHs. In particular, the degradation efficiency of total PAHs in NASCA-HA was lowered to 31.0%. PAH congeners in HAs showed a large difference in oxidative removal efficiency. Low-ring PAH was more easily degraded than medium- and high-ring PAHs, and in most treatments, fluoranthene and pyrene in the medium ring and benzo[a]pyrene in the high ring demonstrated higher efficiencies than other PAHs with the same number of rings. Our findings are useful in promoting the accurate and green remediation of PAH-contaminated soils.
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Affiliation(s)
- Wenbing Tan
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Niankai Liu
- Department of the History of Science, Tsinghua University, Beijing, 100084, China
| | - Qiuling Dang
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Dongyu Cui
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Beidou Xi
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Hong Yu
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
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25
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Zhou N, Liu Y, Cao S, Guo R, Ma Y, Chen J. Biodegradation of bisphenol compounds in the surface water of Taihu Lake and the effect of humic acids. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 723:138164. [PMID: 32392677 DOI: 10.1016/j.scitotenv.2020.138164] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/18/2020] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
Bisphenol analogues (BPs) pollution in the aquatic environment is increasingly a worldwide concern. There is an urgent need to understand the fate of BPs in the aquatic environment. In this study, we studied the biodegradation of eight BPs in Taihu Lake and discussed the effect of humic acid (HA), which was extracted from Taihu Lake sediment, on the disappearance of BPs. Under aerobic conditions, bisphenol AF (BPAF) and bisphenol S (BPS) were recalcitrant to biodegradation in the lake water. The half-lives for bisphenol F (BPF), bisphenol A (BPA), bisphenol B (BPB), bisphenol E (BPE), bisphenol Z (BPZ), and bisphenol M (BPM) ranged from 34 to 75 days in the Taihu Lake water collected in October 2018 and 12-72 days in that collected in May 2019. The biodegradation of BPs in summer was significantly higher than that in autumn. The presence of HA promoted the disappearance of BPs from Taihu Lake water by adsorbing and binding BPs. The disappearance rate of BPs accelerated with increasing concentrations of HA. However, the presence of HA decreased the biodegradation of BPs. When the concentration of HA was 10 mg/L, the single-adsorption capacities for BPS, BPA, BPB, BPM and BPAF were 3.18-10.33 mg/g in the Taihu Lake water with little desorption. BP adsorption and desorption in the BP mixtures were different from that in the single BPs. Competitive desorption occurred among the mixtures. The results of this study are the first to indicate the biodegradation of eight BPs in natural lake water and the possible effect of HA on the fate of BPs in the environment.
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Affiliation(s)
- Nan Zhou
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China; State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Yanhua Liu
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China
| | - Siqi Cao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Ruixin Guo
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China
| | - Yini Ma
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Jianqiu Chen
- School of Engineering, China Pharmaceutical University, Nanjing 210009, China.
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26
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Cao Y, Xin M, Wang B, Lin C, Liu X, He M, Lei K, Xu L, Zhang X, Lu S. Spatiotemporal distribution, source, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in the urbanized semi-enclosed Jiaozhou Bay, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 717:137224. [PMID: 32062240 DOI: 10.1016/j.scitotenv.2020.137224] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 06/10/2023]
Abstract
Coastal contamination by polycyclic aromatic hydrocarbons (PAHs) is a worldwide issue. Nevertheless, the spatiotemporal distribution of PAHs in the urbanized semi-enclosed bays in China remains relatively uncharacterized. Here we present measurements of 15 priority PAHs in the water and sediment of the Jiaozhou Bay, as well the assessment of their spatiotemporal distribution, sources and ecological risk. The total PAH (ΣPAH) concentrations ranged from 23.6 to 86.2 ng L -1 in the water and from 37.7 to 290.9 ng g-1 in the sediment. The average ΣPAH concentration in the water was significantly higher in the winter (52.8 ng L -1) than in the spring (30.4 ng L -1) (α = 0.05 level). Average concentration of phenanthrene in the water was 8.9 ng L-1 in the spring and 15.7 ng L-1 in the winter and the highest of PAHs, contributing about 29.4% to ΣPAHs. Compared with three-ring PAHs, four- and five-ring PAHs were more tended to accumulate in the sediment, and the partitioning into sediment was influenced by the water salinity. The spatial distribution of ΣPAH concentrations in the water were controlled by water exchange capability. Organic matter content and sediment texture played important roles in determining the spatial distribution of ΣPAHs in the sediment. Molecular diagnostic ratio analysis indicated that pyrogenic source was the main source for PAHs in the Bay. Specifically, the positive matrix factorization (PMF) model indicated that vehicle emission, biomass combustion, coal combustion, and petrogenic sources contributed for 41.6, 20.2, 20, and 18.2% of ΣPAHs, respectively. The risk assessment by sediment quality guidelines suggested that adverse biological effects are expected to occur rarely in the sediment.
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Affiliation(s)
- Yuanxin Cao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Ming Xin
- The First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao 266061, China
| | - Baodong Wang
- The First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao 266061, China
| | - Chunye Lin
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Xitao Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Mengchang He
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Kai Lei
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Ling Xu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Xuan Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Shuang Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
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27
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Hakim A, Suzuki T, Kobayashi M. Strength of Humic Acid Aggregates: Effects of Divalent Cations and Solution pH. ACS OMEGA 2019; 4:8559-8567. [PMID: 31459946 PMCID: PMC6648436 DOI: 10.1021/acsomega.9b00124] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 05/07/2019] [Indexed: 05/25/2023]
Abstract
Aggregation-dispersion, charging, and aggregate strength of Leonardite humic acid (LHA) were investigated in CaCl2 and MgCl2 solutions as a function of pH and ionic strength (I). The strength or the withstanding force of aggregates of humic substances (HSs) against breakage is important because this force influences the transport and distribution of pollutants and nutrients along with HSs through the change in the size of HS aggregates as a transport unit. We observed the dominancy of aggregation of LHA at high pH than at low pH in every case of CaCl2 and MgCl2 solutions. This observation suggests the higher binding efficiency of these divalent ions at high pH, though there was no obvious relation with electrophoretic mobility and aggregation of LHA. Further, we first revealed the numerical value of the strength of HS aggregates by using a simple experimental setup of aggregate breakup under laminar converging flow through a capillary tube. The obtained values of the strength of LHA aggregates were higher in the presence of CaCl2 solution than MgCl2 solution, and the strength increased with pH. The highest strengths of LHA aggregates in 30 mM (I) CaCl2 and MgCl2 solutions were around 5.8 and 2.4 nN, respectively, at pH around 9.
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Affiliation(s)
- Azizul Hakim
- Graduate
School of Life and Environmental Sciences and Faculty of Life and Environmental
Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8572, Ibaraki, Japan
- Department
of Soil Science, University of Chittagong, Chittagong 4331, Bangladesh
| | - Tomoharu Suzuki
- Graduate
School of Life and Environmental Sciences and Faculty of Life and Environmental
Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8572, Ibaraki, Japan
| | - Motoyoshi Kobayashi
- Graduate
School of Life and Environmental Sciences and Faculty of Life and Environmental
Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8572, Ibaraki, Japan
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28
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John C, Kishimoto M, Johzaki T, Higashiguchi T, Kakunaka N, Matsumoto Y, Hasegawa N, Nishikino M, Ejima T, Sunahara A, Endo T, Namba S. Enhancement of water-window soft x-ray emission from laser-produced Au plasma under low-pressure nitrogen atmosphere. OPTICS LETTERS 2019; 44:1439-1442. [PMID: 30874670 DOI: 10.1364/ol.44.001439] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 02/21/2019] [Indexed: 06/09/2023]
Abstract
To generate bright water-window (WW) soft x rays (2.3-4.4 nm), gold slab targets were irradiated with laser pulses (1064 nm, 7 ns, 1 J). Emission spectroscopy showed that the introduction of low-pressure nitrogen enhanced the soft x-ray yield emitted from the laser-produced Au plasma. The intensity of the WW x-ray transported in a 400-Pa N2 atmosphere from the laser-produced plasma increased by 3.8 times over that in vacuum. Considering a strong x-ray absorption, the x-ray yield emitted directly from the Au plasma in the N2 gas was evaluated to be 13 times higher than that in vacuum. Although similar measurements were made for various gases, only N2 gas causes an increase in a soft x-ray yield. The processes leading to this enhancement mechanism were revealed by using hydrodynamic simulation and atomic structure codes.
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29
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Kleber M, Lehmann J. Humic Substances Extracted by Alkali Are Invalid Proxies for the Dynamics and Functions of Organic Matter in Terrestrial and Aquatic Ecosystems. JOURNAL OF ENVIRONMENTAL QUALITY 2019; 48:207-216. [PMID: 30951127 DOI: 10.2134/jeq2019.01.0036] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The conceptual rigor of using organic materials extracted from soil by alkali, called , as proxies for soil organic matter has been questioned for almost 180 years. However, the humic substances paradigm, i.e., the understanding that alkali-extracted humic substances are newly synthesized materials with unique properties that are distinct from non-humic organic matter, continues to be propagated throughout the literature. Here, we revisit the mechanistic background of the extraction process to show that alkaline extraction is unable to discriminate for the chemical history of a compound. For this reason, alkaline extraction cannot distinguish between (i) materials that have undergone secondary synthesis or humification ("humic" substances), and (ii) materials that are decorated with ionizable functional groups for other reasons, such as oxidative depolymerization ("non-humic" substances). While this mechanistic consideration alone renders invalid a distinction between humic substances and non-humic substances based on alkaline extraction, we further show that the evidence available to date does not support the assumption that processes of secondary synthesis create quantitatively significant proportions of "chemically reactive, yet recalcitrant" materials in natural environments. Any definition of humic substances that invokes both alkaline extraction and secondary synthesis is thus flawed on at least two accounts: (i) alkaline extraction is unable to achieve its purpose of separating humic from non-humic substances, and (ii) the assertion that the extracted materials have unique molecular properties as a consequence of secondary synthesis cannot be proven because alkaline extraction cannot separate materials created by secondary synthesis from other, ionizable organic compounds. Finally, we point out that since the definition of humic substances is tied to the alkaline-extraction procedure, neither the existence of operationally defined humic substances in the environment nor their chemical integrity during the course of alkaline extraction can be independently verified. We conclude that organic materials extracted by alkali require appropriate nomenclature and rigorous definition to merit consideration in teaching, research, and application.
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30
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Li Q, Xie L, Jiang Y, Fortner JD, Yu K, Liao P, Liu C. Formation and stability of NOM-Mn(III) colloids in aquatic environments. WATER RESEARCH 2019; 149:190-201. [PMID: 30447524 DOI: 10.1016/j.watres.2018.10.094] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 10/25/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
Soluble Mn(III) species stabilized by natural organic matter (NOM) plays a crucial role in a number of biogeochemical processes. To date, current understanding of these phenomena has been primarily concerned on the occurrence and chemistry of soluble NOM-Mn(III) complexes; much less is known regarding the formation and stability of NOM-Mn(III) colloids in the environment. This presents a critical knowledge gap with regard to biogeochemical cycling of manganese and associated carbon, and for predicting the fate and transport of colloid-associated contaminants, nutrients, and trace metals. In this work, we have characterized the chemical and physical properties of humic acid based (HA)-Mn(III) colloids formed over a range of environmentally relevant conditions and quantified their subsequent aggregation and stability behaviors. Results show that molar C/Mn ratios and HA types (Aldrich HA (AHA) and Pahokee peat soil HA (PPSHA)) are critical factors influencing HA-Mn(III) colloidal properties. Both the amount and the stability of HA-Mn(III) colloids increased with increasing initial molar C/Mn ratios, regardless of HA type. The correlation between the critical coagulation concentration (CCC) and zeta potential (R2 > 0.97) suggests that both Derjaguin-Landau-Verwey-Overbeek (DLVO) type and non-DLVO interactions are responsible for enhanced stability of HA-Mn(III) colloids. For a given C/Mn ratio, PPSHA-Mn(III) colloids are significantly more stable against aggregation than AHA-Mn(III) colloids, which is likely due to stronger electrostatic interactions, hydration interactions, and steric hindrance. Further examination in real-world waters indicates that the HA-Mn(III) colloids are highly stable in surface river water, but become unstable (i.e. extensive aggregation) in solutions representing a groundwater-seawater interaction zone. Overall, this study provides new insights into the formation and stability of NOM-Mn(III) colloids which are critical for understanding Mn-based colloidal behavior(s), and thus Mn cycling processes, in aquatic systems.
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Affiliation(s)
- Qianqian Li
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, 1088 Xueyuan Road, Shenzhen, 518055, PR China
| | - Lin Xie
- Department of Physics, Southern University of Science and Technology, 1088 Xueyuan Road, Shenzhen, 518055, PR China
| | - Yi Jiang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - John D Fortner
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Kai Yu
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, 1088 Xueyuan Road, Shenzhen, 518055, PR China
| | - Peng Liao
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, 1088 Xueyuan Road, Shenzhen, 518055, PR China.
| | - Chongxuan Liu
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, 1088 Xueyuan Road, Shenzhen, 518055, PR China.
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31
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González-Márquez LC, Hansen AM, González-Farias FA. Effect of mono and divalent salts on the conformation and composition of a humic acid and on atrazine adsorption. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:17509-17518. [PMID: 29658067 DOI: 10.1007/s11356-018-1939-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 04/03/2018] [Indexed: 06/08/2023]
Abstract
We investigated the effects of sodium and calcium chlorides on the conformation and composition of a purified Aldrich humic acid (PAHA), as well as on the adsorption of atrazine. The PAHA was treated with 1, 10, and 100 mM NaCl, CaCl2, or a mixture of NaCl and CaCl2 (molar ratio 5:1) at pH 7.5 and 8.5. The conformation of treated PAHA was characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM) and spectral changes of functional groups of PAHA by Fourier transform infrared spectroscopy (FTIR). AFM and TEM images showed an increase in the aggregation of the PAHA as salinity increased. FTIR spectra revealed that changes in the aggregation of the PAHA were principally due to the formation of bridged interactions between calcium and carboxylate groups in the PAHA. The adsorption of atrazine on > 0.45 μm PAHA decreased as salt concentrations and pH increased. This reduction of atrazine adsorption was explained by the decrease in available adsorption sites due to agglomeration of PAHA.
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Affiliation(s)
| | - Anne M Hansen
- Instituto Mexicano de Tecnología del Agua, Paseo Cuauhnáhuac 8532, 62550, Jiutepec, Morelos, Mexico.
| | - Fernando A González-Farias
- Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Mexico City, Mexico
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32
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Zhang F, Yang L, Liu X, Li Y, Fang H, Wang X, Alharbi NS, Li J. Sorption of 17β-estradiol to the dissolved organic matter from animal wastes: effects of composting and the role of fulvic acid-like aggregates. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16875-16884. [PMID: 29619641 DOI: 10.1007/s11356-018-1402-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/25/2018] [Indexed: 06/08/2023]
Abstract
Steroid estrogens, such as 17β-estradiol (E2), in animal manure pose a potential threat to the aquatic environment. The transport and estrogenicity of estrogens influence the sorption of estrogens to dissolved organic matter (DOM) in animal manure, and composting treatment alters the structure and composition of the manure. The objectives of the present study were to identify the contribution of the molecular composition of DOM of composted manure to the sorption of E2 and then elucidate the dominant mechanisms involved in the interaction of E2 with manure-derived DOM. The excitation-emission matrix (EEM) spectra and atomic force microscopy (AFM) showed that composting significantly altered the chemical composition and structure of DOM. A decrease in the atomic ratios of oxygen (O)/carbon (C) occurred in conjunction with the formation of DOM aggregates in the composted manure, indicating that the hydrophilicity and polarity of the DOM decreased after composting. Composting increased the sorption coefficients (KDOC-E2) for E2 to DOM, and KDOC-E2 was positively correlated with the proportion of the fulvic acid (FA)-like fraction and molecular weight (MW) fractions of the DOM (range of 1.0 × 103-7.0 × 103 Da and 7.0 × 103-1.4 × 104 Da). Specifically, E2 showed a tendency for sorption to medium-sized FA-like molecules of DOM aggregates in composted manure. Hydrophobic forces and π-π binding appeared to be the main mechanisms underlying the aforementioned interaction.
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Affiliation(s)
- Fengsong Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Linsheng Yang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xia Liu
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031, China
| | - Yanxia Li
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Huajun Fang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xingrun Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Njud S Alharbi
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Jiaxing Li
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031, China.
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Swiech WM, Hamerton I, Zeng H, Watson DJ, Mason E, Taylor SE. Water-based fractionation of a commercial humic acid. Solid-state and colloidal characterization of the solubility fractions. J Colloid Interface Sci 2017; 508:28-38. [PMID: 28818654 DOI: 10.1016/j.jcis.2017.08.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 08/09/2017] [Accepted: 08/10/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND HYPOTHESIS Humic acid (HA) is of considerable environmental significance, being a major component of soil, as well as being considered for application in other technological areas. However, its structure and colloidal properties continue to be the subject of debate, largely owing to its molecular complexity and association with other humic substances and mineral matter. As a class, HA is considered to comprise supramolecular assemblies of heterogeneous species, and herein we consider a simple route for the separation of some HA sub-fractions. EXPERIMENTS A commercial HA sample from Sigma-Aldrich has been fractionated into two soluble (S1, S2) and two insoluble (I1, I2) fractions by successive dissolution in deionized water at near-neutral pH. These sub-fractions have been characterized by solution and solid-state approaches. FINDINGS Using this simple approach, the HA has been shown to contain non-covalently bonded species with different polarity and water solubility. The soluble and insoluble fractions have very different chemical structures, as revealed particularly by their solid-state properties (13C NMR and IR spectroscopy, and TGA); in particular, S1 and S2 are characterized by higher carbonyl and aromatic contents, compared with I1 and I2. As shown by solution SAXS measurements and AFM, the soluble fractions behave as hydrophilic colloidal aggregates of at least 50nm diameter.
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Affiliation(s)
- Weronika M Swiech
- Centre for Petroleum and Surface Chemistry, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Ian Hamerton
- Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Huang Zeng
- BP America, Upstream Technology, 501 Westlake Blvd., Houston, TX 77079, USA
| | - David J Watson
- Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Eleonore Mason
- Department of Chemistry, University of Reading, Reading RG6 6AD, UK
| | - Spencer E Taylor
- Centre for Petroleum and Surface Chemistry, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK.
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Han C, Yang W, Yang H, Xue X. Enhanced photochemical conversion of NO 2 to HONO on humic acids in the presence of benzophenone. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 231:979-986. [PMID: 28888942 DOI: 10.1016/j.envpol.2017.08.107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/14/2017] [Accepted: 08/30/2017] [Indexed: 06/07/2023]
Abstract
The photochemical conversion of NO2 to HONO on humic acids (HA) in the presence of benzophenone (BP) was investigated using a flow tube reactor coupled to a NOx analyzer at ambient pressure. BP significantly enhanced the reduction of NO2 to HONO on HA under simulated sunlight, as shown by the increase of NO2 uptake coefficient (γ) and HONO yield with the mass ratio of BP to HA. The γ and HONO yield on the mixtures of HA and BP obviously depended on the environmental conditions. Both γ and HONO yield increased with the increase of irradiation intensity and temperature, whereas they decreased with pH. The γ exhibited a negative dependence on the NO2 concentration, which had slight influences on the HONO yield. There were maximum values for the γ and HONO yield at relative humidity (RH) of 22%. Finally, atmospheric implications about the photochemical reaction of NO2 and HA in the presence of photosensitive species were discussed.
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Affiliation(s)
- Chong Han
- School of Metallurgy, Northeastern University, Shenyang, 110819, China.
| | - Wangjin Yang
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
| | - He Yang
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
| | - Xiangxin Xue
- School of Metallurgy, Northeastern University, Shenyang, 110819, China
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35
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Antifouling ceramic membrane electrode modified by Magnéli Ti 4 O 7 for electro-microfiltration of humic acid. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.05.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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36
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Li P, Wu H, Liang J, Yin Z, Pan D, Fan Q, Xu D, Wu W. Sorption of Eu(III) at feldspar/water interface: effects of pH, organic matter, counter ions, and temperature. RADIOCHIM ACTA 2017. [DOI: 10.1515/ract-2017-2797] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The sorption of Eu(III) on potassium feldspar (K-feldspar) was studied under various physicochemical conditions such as pH, temperature, counter ions and organic matter. The results showed that the sorption of Eu(III) on K-feldspar significantly increased with the increase of pH, and high Eu(III) concentration can inhibit such immobility to some extent. The presence of humic acid (HA) can increase the sorption of Eu(III) on K-feldspar in low pH range; while inhibit to a large extent under alkaline conditions. It is very interesting that at pH ~6.5, high ionic strength can promote the sorption of Eu(III) on K-feldspar in the presence of HA. In contrast, Eu(III) sorption was restricted obviously by NaCl in the absence of HA. The sorption procedure was involved with ion exchange and/or outer-sphere complexation as well as inner-sphere complexation. The presence of F− and PO4
3− dramatically enhanced Eu(III) sorption on K-feldspar, whereas both SO4
2− and CO3
2− had negative effects on Eu(III) sorption. X-ray photoelectron spectroscopy analysis indicated that Eu(III) tended to form hydrolysates at high initial concentration (3×10−4 mol/L) and high temperature (338 K).
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Affiliation(s)
- Ping Li
- Key Laboratory of Petroleum Resources , Gansu Province/CAS Key Laboratory of Petroleum Resources Research , Institute of Geology and Geophysics, Chinese Academy of Sciences , Lanzhou 730000 , China
| | - Hanyu Wu
- Key Laboratory of Petroleum Resources , Gansu Province/CAS Key Laboratory of Petroleum Resources Research , Institute of Geology and Geophysics, Chinese Academy of Sciences , Lanzhou 730000 , China
- Radiochemistry Laboratory , School of Nuclear Science and Technology , Lanzhou University , Lanzhou 730000 , China
| | - Jianjun Liang
- Key Laboratory of Petroleum Resources , Gansu Province/CAS Key Laboratory of Petroleum Resources Research , Institute of Geology and Geophysics, Chinese Academy of Sciences , Lanzhou 730000 , China
| | - Zhuoxin Yin
- Radiochemistry Laboratory , School of Nuclear Science and Technology , Lanzhou University , Lanzhou 730000 , China
| | - Duoqiang Pan
- Radiochemistry Laboratory , School of Nuclear Science and Technology , Lanzhou University , Lanzhou 730000 , China
| | - Qiaohui Fan
- Key Laboratory of Petroleum Resources , Gansu Province/CAS Key Laboratory of Petroleum Resources Research , Institute of Geology and Geophysics, Chinese Academy of Sciences , Lanzhou 730000 , China
| | - Di Xu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences , Nanjing 210008 , China , Tel.: +86-931-4960831,
| | - Wangsuo Wu
- Radiochemistry Laboratory , School of Nuclear Science and Technology , Lanzhou University , Lanzhou 730000 , China
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Song G, Li Y, Hu S, Li G, Zhao R, Sun X, Xie H. Photobleaching of chromophoric dissolved organic matter (CDOM) in the Yangtze River estuary: kinetics and effects of temperature, pH, and salinity. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2017; 19:861-873. [PMID: 28548140 DOI: 10.1039/c6em00682e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The kinetics and temperature-, pH- and salinity-dependences of photobleaching of chromophoric dissolved organic matter (CDOM) in the Yangtze River estuary (YRE) were evaluated using laboratory solar-simulated irradiation and compared to those of Suwannee River humic substances (SRHSs). Nearly all CDOM in water at the head of the estuary (headwater herein) was photobleachable in both summer and winter, while significant fractions of CDOM (13-29%) were resistant to photobleaching in saltier waters. The photobleaching rate constant in the headwater was 25% higher in summer than that in winter. The absorbed photon-based photobleaching efficiency (PE) increased with temperature following the linear Arrhenius equation. For a 20 °C increase in temperature, PE increased by ∼45% in the headwater and by 70-81% in the saltier waters. PE for YRE samples exhibited minima at pH from 6 to 7 and increased with both lower and higher pH values, contrasting the consistent increase in PE with pH shown by SRHSs. No consistent effect of salinity on PE was observed for both SRHSs and YRE samples. Photobleaching increased the spectral slope coefficient between 275 nm and 295 nm in summer, consistent with the behavior of SRHSs, but decreased it in winter, implying a difference in the molecular composition of chromophores between the two seasons. Temperature, salinity, and pH modified the photoalteration of the spectral shape but their effects varied spatially and seasonally. This study demonstrates that CDOM quality, temperature, and pH should be incorporated into models involving quantification of photobleaching.
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Affiliation(s)
- Guisheng Song
- College of Marine and Environmental Sciences, Tianjin University of Science & Technology, Tianjin 300457, China
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Liu J, Li X, Chen S, Zhang S, Xie S, Xu C, Chen Y, Deng B, Mao C. Nanofabrication and characterization of a grating-based condenser for uniform illumination with hard X-rays. JOURNAL OF SYNCHROTRON RADIATION 2017; 24:595-599. [PMID: 28452750 DOI: 10.1107/s1600577517002247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 02/09/2017] [Indexed: 06/07/2023]
Abstract
In the development of full-field transmission X-ray microscopy for basic study in science and technology, a condenser capable of providing intense illumination with high uniformity and stability on tested specimens in order to achieve high-quality images is essential. The latest design of a square-shaped condenser based on diffractive gratings has demonstrated promising uniformity in illumination. This paper describes in more detail the development of such a beam shaper for hard X-rays at 10 keV with regard to its design, manufacture and optical characterization. The effect of the grating profile on the diffracted intensity has been theoretically predicted by numerical simulation using the finite-difference time-domain method. Based on this, the limitations of the grating-based condenser are discussed.
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Affiliation(s)
- Jianpeng Liu
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Xin Li
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Shuo Chen
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Sichao Zhang
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Shanshan Xie
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Chen Xu
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yifang Chen
- Nanolithography and Application Research Group, State Key Laboratory of ASIC and System, School of Information Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Biao Deng
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China
| | - Chenwen Mao
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China
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39
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Vadasarukkai YS, Gagnon GA. Influence of the Mixing Energy Consumption Affecting Coagulation and Floc Aggregation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:3480-3489. [PMID: 28206742 DOI: 10.1021/acs.est.6b06281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The operational significance of energy-intensive rapid mixing processes remains unaddressed in coagulation and flocculation of insoluble precipitates (flocs), which play an important role in the removal of impurities from drinking water supplies. In this study, the influence of rapid mixing and associated mixing energy on floc aggregation was examined for a surface water source characterized by a high fraction of aquatic humic matter. Infrared spectral analyses showed that the colloidal complexes resulting from ligand exchange between iron and dissolved natural organic matter (DOM) were not substantially influenced by the mixing energy input. This signified that DOM removal by coagulation can be achieved at lower mixing intensity, thereby reducing energy consumption. In contrast, macroscopic investigations showed the coagulation mixing energy affected floc size distributions during the slow mixing stage in flocculation and, to some extent, their settling characteristics. The results from analysis of floc properties clearly showed that more mixing energy was expended than necessary in coagulation, which is typically designed at a high mixing intensity range of 600-1000 s-1 in treatment plants. The key findings from this study have practical implications to water utilities to strategically meet water quality goals while reducing energy demands.
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40
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Al-Faiyz YS. CPMAS 13 C NMR characterization of humic acids from composted agricultural Saudi waste. ARAB J CHEM 2017. [DOI: 10.1016/j.arabjc.2012.12.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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41
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Liao P, Li W, Wang D, Jiang Y, Pan C, Fortner JD, Yuan S. Effect of reduced humic acid on the transport of ferrihydrite nanoparticles under anoxic conditions. WATER RESEARCH 2017; 109:347-357. [PMID: 27926882 DOI: 10.1016/j.watres.2016.11.069] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 11/27/2016] [Accepted: 11/30/2016] [Indexed: 06/06/2023]
Abstract
Humic acid (HA) occurs ubiquitously in the subsurface environments and is well-known to play a critical role in the fate and transport of ferrihydrite nanoparticles (NPs) and NPs-associated contaminants. Under anoxic conditions, HA can readily be reduced by microorganisms or geochemical reducing species, and the mechanisms and kinetics of ferrihydrite reduction by reduced HA (HAred) are well-documented; however, the role of these redox reactions on the transport of ferrihydrite NPs is largely underestimated. This study provides new knowledge regarding the role of HA (both reduced HA (HAred) and oxidized HA (HAox)) of environmentally relevant concentrations (0-50 mg C/L) on the transport of ferrihydrite NPs in anoxic sand columns. Our findings show that, regardless of the redox state, the presence of a low concentration of HA (3 mg C/L) inhibited ferrihydrite NP's transport due to enhanced aggregation (and deposition) between positively charged ferrihydrite NPs and negatively charged HA molecules. In contrast, higher HA (both HAred and HAox) concentration (≥10 mg C/L) significantly enhanced the mobility of ferrihydrite NPs, primarily due to the enhanced electrostatic and steric stabilization originating from excessively adsorbed HA molecules. Interestingly, the transport of ferrihydrite NPs is substantially lower in the presence of HAred than in the presence of HAox. This distinct effect (HAred vs. HAox) on the particle transport is attributed to the fact that reductive dissolution of ferrihydrite NPs occurs in the presence of HAred (ferrihydrite dissolves and thus total breakthrough decreases), but not in the presence of HAox. Furthermore, the abatement extent of ferrihydrite NPs transport triggered by the presence of HAred is dependent on dissolved HAred concentration. Taken together, our findings provide direct, and much needed insights into the distinct roles of redox state of HA on the transport of redox-sensitive metal-bearing NPs in porous media.
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Affiliation(s)
- Peng Liao
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan, 430074, PR China
| | - Wenlu Li
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, 63130, United States
| | - Dengjun Wang
- Department of Plant and Soil Sciences, University of Delaware, Newark, DE, 19716, United States
| | - Yi Jiang
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, 63130, United States
| | - Chao Pan
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, 63130, United States
| | - John D Fortner
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, 63130, United States
| | - Songhu Yuan
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan, 430074, PR China.
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42
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Saleh NB, Milliron DJ, Aich N, Katz LE, Liljestrand HM, Kirisits MJ. Importance of doping, dopant distribution, and defects on electronic band structure alteration of metal oxide nanoparticles: Implications for reactive oxygen species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:926-932. [PMID: 27350094 DOI: 10.1016/j.scitotenv.2016.06.145] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 06/18/2016] [Accepted: 06/18/2016] [Indexed: 05/10/2023]
Abstract
Metal oxide nanoparticles (MONPs) are considered to have the potency to generate reactive oxygen species (ROS), one of the key mechanisms underlying nanotoxicity. However, the nanotoxicology literature demonstrates a lack of consensus on the dominant toxicity mechanism(s) for a particular MONP. Moreover, recent literature has studied the correlation between band structure of pristine MONPs to their ability to introduce ROS and thus has downplayed the ROS-mediated toxicological relevance of a number of such materials. On the other hand, material science can control the band structure of these materials to engineer their electronic and optical properties and thereby is constantly modulating the pristine electronic structure. Since band structure is the fundamental material property that controls ROS-producing ability, band tuning via introduction of dopants and defects needs careful consideration in toxicity assessments. This commentary critically evaluates the existing material science and nanotoxicity literature and identifies the gap in our understanding of the role of important crystal structure features (i.e., dopants and defects) on MONPs' electronic structure alteration as well as their ROS-generation capability. Furthermore, this commentary provides suggestions on characterization techniques to evaluate dopants and defects on the crystal structure and identifies research needs for advanced theoretical predictions of their electronic band structures and ROS-generation abilities. Correlation of electronic band structure and ROS will not only aid in better mechanistic assessment of nanotoxicity but will be impactful in designing and developing ROS-based applications ranging from water disinfection to next-generation antibiotics and even cancer therapeutics.
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Affiliation(s)
- Navid B Saleh
- Department of Civil, Architectural, and Environmental Engineering, University of Texas, Austin, TX 78712, United States.
| | - Delia J Milliron
- McKetta Department of Chemical Engineering, University of Texas, Austin, TX 78712, United States
| | - Nirupam Aich
- Department of Civil, Structural and Environmental Engineering, University at Buffalo, The State University of New York, Buffalo, NY, 14260, United States
| | - Lynn E Katz
- Department of Civil, Architectural, and Environmental Engineering, University of Texas, Austin, TX 78712, United States
| | - Howard M Liljestrand
- Department of Civil, Architectural, and Environmental Engineering, University of Texas, Austin, TX 78712, United States
| | - Mary Jo Kirisits
- Department of Civil, Architectural, and Environmental Engineering, University of Texas, Austin, TX 78712, United States
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44
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Tong F, Gu X, Gu C, Xie J, Xie X, Jiang B, Wang Y, Ertunc T, Schäffer A, Ji R. Stimulation of Tetrabromobisphenol A Binding to Soil Humic Substances by Birnessite and the Chemical Structure of the Bound Residues. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:6257-6266. [PMID: 27223831 DOI: 10.1021/acs.est.5b06265] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Studies have shown the main fate of the flame retardant tetrabromobisphenol A (TBBPA) in soils is the formation of bound residues, and mechanisms on it are less-understood. This study investigated the effect of birnessite (δ-MnO2), a naturally occurring oxidant in soils, on the formation of bound residues. (14)C-labeled TBBPA was used to investigate the pH dependency of TBBPA bound-residue formation to two soil humic acids (HAs), Elliott soil HA and Steinkreuz soil HA, in the presence of δ-MnO2. The binding of TBBPA and its transformation products to both HAs was markedly increased (3- to 17-fold) at all pH values in the presence of δ-MnO2. More bound residues were formed with the more aromatic Elliott soil HA than with Steinkreuz soil HA. Gel-permeation chromatography revealed a uniform distribution of the bound residues within Steinkreuz soil HA and a nonuniform distribution within Elliott soil HA. (13)C NMR spectroscopy of (13)C-TBBPA residues bound to (13)C-depleted HA suggested that in the presence of δ-MnO2, binding occurred via ester and ether and other types of covalent bonds besides HA sequestration. The insights gained in this study contribute to an understanding of the formation of TBBPA bound residues facilitated by δ-MnO2.
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Affiliation(s)
| | | | | | | | | | | | | | - Tanya Ertunc
- Institute for Environmental Research, RWTH Aachen University , D-52056 Aachen, Germany
| | - Andreas Schäffer
- Institute for Environmental Research, RWTH Aachen University , D-52056 Aachen, Germany
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He W, Chen M, Schlautman MA, Hur J. Dynamic exchanges between DOM and POM pools in coastal and inland aquatic ecosystems: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 551-552:415-428. [PMID: 26881732 DOI: 10.1016/j.scitotenv.2016.02.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/03/2016] [Accepted: 02/04/2016] [Indexed: 06/05/2023]
Abstract
Dynamic exchanges between dissolved organic matter (DOM) and particulate organic matter (POM) plays a critical role in organic carbon cycling in coastal and inland aquatic ecosystems, interactions with aquatic organisms, mobility and bioavailability of pollutants, among many other ecological and geochemical phenomena. Although DOM-POM exchange processes have been widely studied from different aspects, little to no effort has been made to date to provide a comprehensive, mechanistic, and micro-spatial schema for understanding various exchange processes occurring in different aquatic ecosystems in a unified way. The phenomena occurring between DOM and POM were explained here with the homogeneous and heterogeneous mechanisms. In the homogeneous mechanism, the participating components are only organic matter (OM) constituents themselves with aggregation and dissolution involved, whereas OM is associated with other components such as minerals and particulate colloids in the heterogeneous counterpart. Besides the generally concerned processes of aggregation/dissolution and adsorption/desorption, other ecological factors such as sunlight and organisms can also participate in DOM-POM exchanges through altering the chemical nature of OM. Despite the limitation of current analytical technologies, many unknown and/or unquantified processes need to be identified to unravel the complicated exchanges of OM between its dissolved and particulate states. Based on the review of several previous mathematical models, we proposed a unified conceptual model to describe all major dynamic exchange mechanisms on the basis of exergy theory. More knowledge of dynamic DOM-POM exchanges is warranted to overcome the potential problems arising from a simple division of OM into dissolved versus particulate states and to further develop more sophisticated mathematic models.
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Affiliation(s)
- Wei He
- Department of Environment and Energy, Sejong University, Seoul 143-747, South Korea
| | - Meilian Chen
- Department of Environment and Energy, Sejong University, Seoul 143-747, South Korea
| | - Mark A Schlautman
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625-6510, United States
| | - Jin Hur
- Department of Environment and Energy, Sejong University, Seoul 143-747, South Korea.
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Zhu X, He J, Su S, Zhang X, Wang F. Concept model of the formation process of humic acid-kaolin complexes deduced by trichloroethylene sorption experiments and various characterizations. CHEMOSPHERE 2016; 151:116-123. [PMID: 26933902 DOI: 10.1016/j.chemosphere.2016.02.068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/10/2016] [Accepted: 02/16/2016] [Indexed: 06/05/2023]
Abstract
To explore the interactions between soil organic matter and minerals, humic acid (HA, as organic matter), kaolin (as a mineral component) and Ca(2+) (as metal ions) were used to prepare HA-kaolin and Ca-HA-kaolin complexes. These complexes were used in trichloroethylene (TCE) sorption experiments and various characterizations. Interactions between HA and kaolin during the formation of their complexes were confirmed by the obvious differences between the Qe (experimental sorbed TCE) and Qe_p (predicted sorbed TCE) values of all detected samples. The partition coefficient kd obtained for the different samples indicated that both the organic content (fom) and Ca(2+) could significantly impact the interactions. Based on experimental results and various characterizations, a concept model was developed. In the absence of Ca(2+), HA molecules first patched onto charged sites of kaolin surfaces, filling the pores. Subsequently, as the HA content increased and the first HA layer reached saturation, an outer layer of HA began to form, compressing the inner HA layer. As HA loading continued, the second layer reached saturation, such that an outer-third layer began to form, compressing the inner layers. In the presence of Ca(2+), which not only can promote kaolin self-aggregation but can also boost HA attachment to kaolin, HA molecules were first surrounded by kaolin. Subsequently, first and second layers formed (with inner layer compression) via the same process as described above in the absence of Ca(2+), except that the second layer continued to load rather than reach saturation, within the investigated conditions, because of enhanced HA aggregation caused by Ca(2+).
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Affiliation(s)
- Xiaojing Zhu
- School of Water Resources and Environment, and Beijing Key Laboratory of Water Resources and Environment Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China.
| | - Jiangtao He
- School of Water Resources and Environment, and Beijing Key Laboratory of Water Resources and Environment Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China.
| | - Sihui Su
- School of Water Resources and Environment, and Beijing Key Laboratory of Water Resources and Environment Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China
| | - Xiaoliang Zhang
- School of Water Resources and Environment, and Beijing Key Laboratory of Water Resources and Environment Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China
| | - Fei Wang
- School of Water Resources and Environment, and Beijing Key Laboratory of Water Resources and Environment Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China
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Emmerton CA, St Louis VL, Humphreys ER, Gamon JA, Barker JD, Pastorello GZ. Net ecosystem exchange of CO2 with rapidly changing high Arctic landscapes. GLOBAL CHANGE BIOLOGY 2016; 22:1185-1200. [PMID: 26279166 DOI: 10.1111/gcb.13064] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/25/2015] [Indexed: 06/04/2023]
Abstract
High Arctic landscapes are expansive and changing rapidly. However, our understanding of their functional responses and potential to mitigate or enhance anthropogenic climate change is limited by few measurements. We collected eddy covariance measurements to quantify the net ecosystem exchange (NEE) of CO2 with polar semidesert and meadow wetland landscapes at the highest latitude location measured to date (82°N). We coupled these rare data with ground and satellite vegetation production measurements (Normalized Difference Vegetation Index; NDVI) to evaluate the effectiveness of upscaling local to regional NEE. During the growing season, the dry polar semidesert landscape was a near-zero sink of atmospheric CO2 (NEE: -0.3 ± 13.5 g C m(-2) ). A nearby meadow wetland accumulated over 300 times more carbon (NEE: -79.3 ± 20.0 g C m(-2) ) than the polar semidesert landscape, and was similar to meadow wetland NEE at much more southerly latitudes. Polar semidesert NEE was most influenced by moisture, with wetter surface soils resulting in greater soil respiration and CO2 emissions. At the meadow wetland, soil heating enhanced plant growth, which in turn increased CO2 uptake. Our upscaling assessment found that polar semidesert NDVI measured on-site was low (mean: 0.120-0.157) and similar to satellite measurements (mean: 0.155-0.163). However, weak plant growth resulted in poor satellite NDVI-NEE relationships and created challenges for remotely detecting changes in the cycling of carbon on the polar semidesert landscape. The meadow wetland appeared more suitable to assess plant production and NEE via remote sensing; however, high Arctic wetland extent is constrained by topography to small areas that may be difficult to resolve with large satellite pixels. We predict that until summer precipitation and humidity increases enough to offset poor soil moisture retention, climate-related changes to productivity on polar semideserts may be restricted.
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Affiliation(s)
- Craig A Emmerton
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
| | - Vincent L St Louis
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
| | - Elyn R Humphreys
- Department of Geography and Environmental Studies, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - John A Gamon
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
- Department of Earth & Atmospheric Sciences, University of Alberta, Edmonton, AB, T6G 2E3, Canada
| | - Joel D Barker
- School of Earth Sciences, Ohio State University, Marion, OH, 43210, USA
| | - Gilberto Z Pastorello
- Computational Research Division, Lawrence Berkeley National Lab, Berkeley, CA, 94720-8150, USA
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48
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She Q, Wang R, Fane AG, Tang CY. Membrane fouling in osmotically driven membrane processes: A review. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2015.10.040] [Citation(s) in RCA: 525] [Impact Index Per Article: 65.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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The contentious nature of soil organic matter. Nature 2015; 528:60-8. [DOI: 10.1038/nature16069] [Citation(s) in RCA: 1630] [Impact Index Per Article: 181.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 10/08/2015] [Indexed: 01/24/2023]
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Vadasarukkai YS, Gagnon GA. Application of low-mixing energy input for the coagulation process. WATER RESEARCH 2015; 84:333-341. [PMID: 26275637 DOI: 10.1016/j.watres.2015.07.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 07/15/2015] [Accepted: 07/30/2015] [Indexed: 06/04/2023]
Abstract
Rapid-mixing tanks with mechanical mixers are a common design used in treatment plants. Yet, the role of such rapid-mixing systems on the effectiveness of the coagulation performance is unclear. This study looked at optimizing the direct energy used in the coagulation process for removal of natural dissolved organic matter (DOM). The role of coagulation mixing intensity (G-value) on total organic carbon (TOC) and turbidity removal was examined for the water types with high organic content, with a specific ultraviolet absorbance (SUVA) of at least 2-2.5 units of m(-1) of absorbance per mg/L. A standard jar test using ferric sulfate coagulant was performed to optimize the chemical condition in coagulation for removal of dissolved organics as well as particles. The jar test analysis at an acidic pH (4.5 ± 0.3) required an iron dose <0.3 mM to arrive at an optimal coagulant concentration and resulted in above 75% of TOC removal. The influence of coagulation mixing on TOC and turbidity removal was evaluated at G varying from 0 to 1500 s(-1) at the optimized coagulant dose and pH conditions for enhanced coagulation. In this study, a combined effective removal of TOC and turbidity was achieved at a low-mixing intensity range of 110 s(-1) < G < 450 s(-1). Coagulation operated at G greater than 450 s(-1) showed negligible improvement in TOC removal. Minimizing energy consumption in enhanced coagulation is feasible at the proposed mixing intensity range (i.e., 110 s(-1) < G < 450 s(-1)), without sacrificing the effectiveness of DOM removal by coagulation. These findings represent an opportunity for energy savings for the water industry without sacrificing quality.
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Affiliation(s)
- Yamuna S Vadasarukkai
- Department of Civil & Resource Engineering, Dalhousie University, Halifax, NS, Canada
| | - Graham A Gagnon
- Department of Civil & Resource Engineering, Dalhousie University, Halifax, NS, Canada.
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