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Kratochvílová R, Kráčalík M, Smilková M, Sedláček P, Pekař M, Bradt E, Smilek J, Závodská P, Klučáková M. Functional Hydrogels for Agricultural Application. Gels 2023; 9:590. [PMID: 37504469 PMCID: PMC10378905 DOI: 10.3390/gels9070590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 07/29/2023] Open
Abstract
Ten different hydrogels were prepared and analyzed from the point of view of their use in soil. FT-IR spectra, morphology, swelling ability, and rheological properties were determined for their characterization and appraisal of their stability. The aim was to characterize prepared materials containing different amounts of NPK as mineral fertilizer, lignohumate as a source of organic carbon, and its combination. This study of stability was focused on utility properties in their application in soil-repeated drying/re-swelling cycles and possible freezing in winter. Lignohumate supported the water absorbency, while the addition of NPK caused a negative effect. Pore sizes decreased with NPK addition. Lignohumate incorporated into polymers resulted in a much miscellaneous structure, rich in different pores and voids of with a wide range of sizes. NPK fertilizer supported the elastic character of prepared materials, while the addition of lignohumate shifted their rheological behavior to more liquid. Both dynamic moduli decreased in time. The most stable samples appeared to contain only one fertilizer constituent (NPK or lignohumate). Repeated re-swelling resulted in an increase in elastic character, which was connected with the gradual release of fertilizers. A similar effect was observed with samples that were frozen and defrosted, except samples containing a higher amount of NPK without lignohumate. A positive effect of acrylamide on superabsorbent properties was not confirmed.
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Affiliation(s)
- Romana Kratochvílová
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
| | - Milan Kráčalík
- Institute of Polymer Science, Johannes Kepler University, Altenberger Strasse 69, 4040 Linz, Austria
| | - Marcela Smilková
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
| | - Petr Sedláček
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
| | - Miloslav Pekař
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
| | - Elke Bradt
- Institute of Polymer Science, Johannes Kepler University, Altenberger Strasse 69, 4040 Linz, Austria
| | - Jiří Smilek
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
| | - Petra Závodská
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
| | - Martina Klučáková
- Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, CZ-61200 Brno, Czech Republic
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Maqbool T, Jiang D. Electrokinetic remediation leads to translocation of dissolved organic matter/nutrients and oxidation of aromatics and polysaccharides. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162703. [PMID: 36906032 DOI: 10.1016/j.scitotenv.2023.162703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/03/2023] [Accepted: 03/03/2023] [Indexed: 06/18/2023]
Abstract
Dissolved organic matter (DOM) in the sediment matrix affects contaminant remediation through consumption of oxidants and binding with contaminants. Yet the change in DOM during remediation processes, particularly during electrokinetic remediation (EKR), remains under-investigated. In this work, we elucidated the fate of sediment DOM in EKR using multiple spectroscopic tools under abiotic and biotic conditions. We found that EKR led to significant electromigration of the alkaline-extractable DOM (AEOM) toward the anode, followed by transformation of the aromatics and mineralization of the polysaccharides. The AEOM remaining in the cathode (largely polysaccharides) was resistant to reductive transformation. Limited difference was noted between abiotic and biotic conditions, indicating the dominance of electrochemical processes when relatively high voltages were applied (1-2 V/cm). The water-extractable organic matter (WEOM), in contrast, showed an increase at both electrodes, which was likely attributable to pH-driven dissociations of humic substances and amino acid-type constituents at the cathode and the anode, respectively. Nitrogen migrated with the AEOM toward the anode, but phosphorus remained immobilized. Understanding the redistribution and transformation of DOM could inform studies on contaminant degradation, carbon and nutrient availability, and sediment structural changes in EKR.
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Affiliation(s)
- Tahir Maqbool
- Department of Civil, Construction, and Environmental Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Daqian Jiang
- Department of Civil, Construction, and Environmental Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA.
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Qin X, Wang Z, Guo C, Guo R, Lv Y, Li M. Fulvic acid degradation in Fenton-like system with bimetallic magnetic carbon aerogel Cu-Fe@CS as catalyst: Response surface optimization, kinetic and mechanism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 306:114500. [PMID: 35051814 DOI: 10.1016/j.jenvman.2022.114500] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 01/04/2022] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
In this study, Cu-Fe bimetallic magnetic chitosan carbon aerogel catalyst (Cu-Fe@CS) was prepared by the sol-gel method to degrade Fulvic acid (FA) in Fenton-like system. Degradation experiment results showed bimetallic catalyst Cu-Fe@CS can degrade more FA than monometallic catalysts (Cu@CS and Fe@CS) due to the synergistic effect between the copper and iron. Plackett Buiman (PB) design showed that pH and temperature exhibited significant influence on FA degradation. The significant factors were optimized by Central Composite Design (CCD), the results revealed that the maximum FA removal reached 96.59% under the conditions of pH 4.07 and temperature 93.77 °C, the corresponding TOC removal reached 77.7%. The kinetic analysis implied that the reaction followed pseudo-first order kinetic with correlation coefficient (R2) = 0.9939. The Arrhenius fitting analysis revealed that Cu-Fe@CS had a lower activation energy (Ea) than Cu@CS and Fe@CS, meaning that reaction was easier to occur in Fenten-like system with Cu-Fe@CS. Catalyst still remained the higher FA and TOC removals of 96.28% and 77.33% after six runs, respectively. The FA removal was reduced by 65.53% with 12 mmol tertiary butanol (TBA) as scavenger, indicating that •OH played an important role in FA degradation. Finally, the catalytic degradation mechanism was proposed.
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Affiliation(s)
- Xia Qin
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China.
| | - Ziyuan Wang
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Chengrui Guo
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Rui Guo
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Yue Lv
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Mingran Li
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China
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Jarukas L, Ivanauskas L, Kasparaviciene G, Baranauskaite J, Marksa M, Bernatoniene J. Determination of Organic Compounds, Fulvic Acid, Humic Acid, and Humin in Peat and Sapropel Alkaline Extracts. Molecules 2021; 26:molecules26102995. [PMID: 34069989 PMCID: PMC8157823 DOI: 10.3390/molecules26102995] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/14/2021] [Accepted: 05/14/2021] [Indexed: 12/03/2022] Open
Abstract
Black, brown, and light peat and sapropel were analyzed as natural sources of organic and humic substances. These specific substances are applicable in industry, agriculture, the environment, and biomedicine with well-known and novel approaches. Analysis of the organic compounds fulvic acid, humic acid, and humin in different peat and sapropel extracts from Lithuania was performed in this study. The dominant organic compound was bis(tert-butyldimethylsilyl) carbonate, which varied from 6.90% to 25.68% in peat extracts. The highest mass fraction of malonic acid amide was in the sapropel extract; it varied from 12.44% to 26.84%. Significant amounts of acetohydroxamic, lactic, and glycolic acid derivatives were identified in peat and sapropel extracts. Comparing the two extraction methods, it was concluded that active maceration was more efficient than ultrasound extraction in yielding higher amounts of organic compounds. The highest amounts of fulvic acid (1%) and humic acid and humin (15.3%) were determined in pure brown peat samples. This research on humic substances is useful to characterize the peat of different origins, to develop possible aspects of standardization, and to describe potential of the chemical constituents.
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Affiliation(s)
- Laurynas Jarukas
- Department of Analytical and toxicological chemistry, Lithuanian University of Health Science, Kaunas, Sukileliu av. 13, LT-50161 Kaunas, Lithuania; (L.J.); (L.I.); (J.B.); (M.M.)
| | - Liudas Ivanauskas
- Department of Analytical and toxicological chemistry, Lithuanian University of Health Science, Kaunas, Sukileliu av. 13, LT-50161 Kaunas, Lithuania; (L.J.); (L.I.); (J.B.); (M.M.)
| | - Giedre Kasparaviciene
- Department of Drug Technology and Social Pharmacy, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania;
- Correspondence: ; Tel.: +37-067191512
| | - Juste Baranauskaite
- Department of Analytical and toxicological chemistry, Lithuanian University of Health Science, Kaunas, Sukileliu av. 13, LT-50161 Kaunas, Lithuania; (L.J.); (L.I.); (J.B.); (M.M.)
| | - Mindaugas Marksa
- Department of Analytical and toxicological chemistry, Lithuanian University of Health Science, Kaunas, Sukileliu av. 13, LT-50161 Kaunas, Lithuania; (L.J.); (L.I.); (J.B.); (M.M.)
| | - Jurga Bernatoniene
- Department of Drug Technology and Social Pharmacy, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania;
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Klučáková M. Mean Activity Coefficients of Humic Acids as Physicochemical Characteristics of Their Behavior in Water Environment. ACS OMEGA 2020; 5:31518-31524. [PMID: 33344803 PMCID: PMC7745220 DOI: 10.1021/acsomega.0c03311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 09/30/2020] [Indexed: 06/12/2023]
Abstract
In this work, the dissociation of humic acids is investigated from the point of view of their mean activity coefficients. They are determined on the basis of two different concepts: sparingly soluble substance and multistep mechanism. It was found that the mean activity coefficients are generally higher, if the traditional concept is applied to the data, excepting the HA-A sample. Both the used concepts provide the mean activity coefficients dependent on the ionic strength, the amount of dissolved humic acids, and the types of electrolyte added in the studied suspensions. Their values based on the concept of a multistep mechanism and determined for humic acids in NaCl and NaI form a continuous curve and the individual character of their ions did not assert. It means that activity coefficients were affected only by the ionic strength and valence factor of the electrolytes irrespective of their chemical composition. The mean activity coefficients obtained for humic acids in HCl are lower in comparison with NaCl and NaI due to the common ion H+. Comparing the results obtained for individual humic acids, we can state that the results obtained for the HA-E sample are very different from those of other samples. It seems that its solubility is very high, but the majority of the dissolved particles remained in the molecular form and only a small amount of ions is formed.
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Klučáková M. Size and Charge Evaluation of Standard Humic and Fulvic Acids as Crucial Factors to Determine Their Environmental Behavior and Impact. Front Chem 2018; 6:235. [PMID: 30027090 PMCID: PMC6041962 DOI: 10.3389/fchem.2018.00235] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 06/04/2018] [Indexed: 11/22/2022] Open
Abstract
In this work, the size and charge of humic and fulvic standards purchased from the International Humic Substances Society are presented and discussed. The secondary structure of humic substances in water environment as well as the size and shape of the dissolved humic species and their changes are ill-defined, very dynamic and can be strongly affected by environmental conditions as the concentration, pH, and ionic strength. They have a strong propensity to aggregate which control their interactions with other components, mobility, and functioning in the environment. Particle size distributions were determined by means of dynamic light scattering, zeta potential by Doppler electrophoresis. The intensity, volume, and number particle size distribution were obtained. Two or three different size fractions were detected in the studied systems. Large macroparticles (>1 μm) were observed in the majority of them, mainly in the case of more concentrated solutions. Medium fractions of fulvic submicroparticles had higher average diameters (500–1,200 nm) than those in humic acids (300–600 nm). Small nanoparticles (<100 nm) were detected mainly in alkaline solutions. Fulvic acids with more functional groups (active sites) can form more easily bigger particles mainly in medium concentration region. Alkaline conditions supported the expansion of humic and fulvic coils and liberation of small particles from them. The colloidal stability, indicated by more negative zeta potentials, was higher for humic acids. In the case of fulvic acids, the colloidal stability increased with increasing pH as a result of the dissociation of their functional groups. The increase of particle size corresponded usually with higher stability.
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Affiliation(s)
- Martina Klučáková
- Faculty of Chemistry, Materials Research Centre, Brno University of Technology, Brno, Czechia
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El Fallah R, Rouillon R, Vouvé F. Spectral characterization of the fluorescent components present in humic substances, fulvic acid and humic acid mixed with pure benzo(a)pyrene solution. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 199:71-79. [PMID: 29571093 DOI: 10.1016/j.saa.2018.03.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 02/09/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
The fate of benzo(a)pyrene (BaP), a ubiquitous contaminant reported to be persistent in the environment, is largely controlled by its interactions with the soil organic matter. In the present study, the spectral characteristics of fluorophores present in the physical fractions of the soil organic matter were investigated in the presence of pure BaP solution. After extraction of humic substances (HSs), and their fractionation into fluvic acid (FA) and humic acid (HA), two fluorescent compounds (C1 and C2) were identified and characterized in each physical soil fraction, by means of fluorescence excitation-emission matrices (FEEMs) and Parallel Factor Analysis (PARAFAC). Then, to each type of fraction having similar DOC content, was added an increasing volume of pure BaP solution in attempt to assess the behavior of BaP with the fluorophores present in each one. The application of FEEMs-PARAFAC method validated a three-component model that consisted of the two resulted fluorophores from HSs, FA and HA (C1 and C2) and a BaP-like fluorophore (C3). Spectral modifications were noted for components C2HSs (C2 in humic substances fraction) (λex/λem: 420/490-520 nm), C2FA (C2 in fulvic acid fraction) (λex/λem: 400/487(517) nm) and C1HA (C1 in humic acid fraction) (λex/λem: 350/452(520) nm). We explored the impact of increasing the volume of the added pure BaP solution on the scores of the fluorophores present in the soil fractions. It was found that the scores of C2HSs, C2FA, and C1HA increased when the volume of the added pure BaP solution increased. Superposition of the excitation spectra of these fluorophores with the emission spectrum of BaP showed significant overlaps that might explain the observed interactions between BaP and the fluorescent compounds present in SOM physical fractions.
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Affiliation(s)
- Rawa El Fallah
- Univ. Perpignan Via Domitia, Biocapteurs-Analyses-Environnement, 66860 Perpignan, France; Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR 3579 Sorbonne Universités (UPMC) Paris 6 et CNRS Observatoire Océanologique, 66650 Banyuls-sur-Mer, France
| | - Régis Rouillon
- Univ. Perpignan Via Domitia, Biocapteurs-Analyses-Environnement, 66860 Perpignan, France; Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR 3579 Sorbonne Universités (UPMC) Paris 6 et CNRS Observatoire Océanologique, 66650 Banyuls-sur-Mer, France
| | - Florence Vouvé
- Univ. Perpignan Via Domitia, Biocapteurs-Analyses-Environnement, 66860 Perpignan, France; Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR 3579 Sorbonne Universités (UPMC) Paris 6 et CNRS Observatoire Océanologique, 66650 Banyuls-sur-Mer, France.
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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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Zhang S, Yuan L, Li W, Lin Z, Li Y, Hu S, Zhao B. Characterization of pH-fractionated humic acids derived from Chinese weathered coal. CHEMOSPHERE 2017; 166:334-342. [PMID: 27700997 DOI: 10.1016/j.chemosphere.2016.09.095] [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: 07/12/2016] [Revised: 09/20/2016] [Accepted: 09/21/2016] [Indexed: 06/06/2023]
Abstract
To reduce the compositional and structural heterogeneity of humic acids (HAs) and achieve better use of HA resources, in this study, we report a new sequential dissolution method for HAs derived from Chinese weathered coal. This method was used to separate HAs into seven fractions by adjusting the pH (3-10) of the extraction solution. The results showed that the HA fractions derived from Chinese weathered coal were concentrated up to 90.31% in the lower pH solutions (3-7). The compositional and structural characteristics of the HA fractions were determined by elemental analysis; ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), and solid-state 13C-nuclear magnetic resonance (NMR) spectroscopies; and other techniques. The results showed significant differences among the HA fractions. The concentrations of the total acidic groups and the carboxyl groups decreased with the increasing pH of the extraction solution. However, the HA fractions derived from extraction solutions with pH 3-4 had relatively lower aromaticity but a higher protonated carbon content. The HA fractions derived from extraction solutions with pH 6-7 had the highest aromaticity and the greatest abundance of COO/N-C=O. This study demonstrated that adjusting the pH of the extraction solution is one way to fractionate HAs from Chinese weathered coal and to obtain HA fractions with compositions and structures that could serve as useful material for study and utilization.
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Affiliation(s)
- Shuiqin Zhang
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Liang Yuan
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wei Li
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhian Lin
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yanting Li
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Shuwen Hu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Bingqiang Zhao
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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