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Zheng Z, Su Y, Schmidt-Rohr K. Vinyl and methyl-ester groups in the insoluble polymer drug patiromer identified and quantified by solid-state NMR. J Pharm Biomed Anal 2024; 246:116228. [PMID: 38781726 DOI: 10.1016/j.jpba.2024.116228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/12/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024]
Abstract
Patiromer (Veltassa®) is a crosslinked, insoluble co-polymer drug used as a nonabsorbent potassium binder, approved for treatment of hyperkalemia. Quantitative solid-state 13C nuclear magnetic resonance (NMR) analysis with comprehensive peak assignment, component quantification, and calculation of mole and weight fractions of monomer units was performed on three doses of patiromer. The workflow is documented in detail. Spectrally edited solid-state 13C NMR spectra of patiromer show =CHn peaks of matching intensity at 116 and 141 ppm, characteristic of -CH=CH2 vinyl groups. Similar spectral features can be observed in earlier studies but were previously ignored. In this study, the vinyl signals are well-resolved in a 2-s direct polarization (DP) spectrum without and with dipolar dephasing, which confirms that these sp2-hybridized carbons are bonded to hydrogen and partially mobile, consistent with vinyl side groups from incompletely reacted divinyl crosslinkers. The vinyl groups account for 1.6% of all carbon, 3% of the monomer units, and nearly 1/3 of the crosslinkers. Furthermore, an unexpected OCH3 moiety accounting for ∼1.2% of all carbons was identified by spectral editing; its chemical shift of 54 ppm is more consistent with a methyl ester than with a methyl ether. It can originate from incomplete hydrolysis of ∼6% of methyl-2-fluoroacrylate, the main monomer of patiromer. Characteristic cross peaks in two-dimensional 1H-13C heteronuclear correlation NMR confirm the presence of the vinyl and OCH3 groups. Trace amounts of xanthan gum are also detected. The quantitative 13C NMR spectrum of patiromer has been matched in a simulation using a model with five monomer units.
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Affiliation(s)
- Zhaoxi Zheng
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
| | - Yongchao Su
- Analytical Research and Development, Merck & Co. Inc., Rahway, NJ 07065, USA; Pharmaceutical Sciences and Clinical Supply, Merck & Co. Inc., Rahway, NJ 07065, USA
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2
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Usuba J, Sun Z, Nguyen HPQ, Raju C, Schmidt-Rohr K, Han GGD. Mechanoactivated amorphization and photopolymerization of styryldipyryliums. COMMUNICATIONS MATERIALS 2024; 5:98. [PMID: 38859933 PMCID: PMC11162349 DOI: 10.1038/s43246-024-00539-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 06/02/2024] [Indexed: 06/12/2024]
Abstract
Conventional topochemical photopolymerization reactions occur exclusively in precisely-engineered photoactive crystalline states, which often produces high-insoluble polymers. To mitigate this, here, we report the mechanoactivation of photostable styryldipyrylium-based monomers, which results in their amorphization-enabled solid-state photopolymerization and produces soluble and processable amorphous polymers. A combination of solid-state nuclear magnetic resonance, X-ray diffraction, and absorption/fluorescence spectroscopy reveals the crucial role of a mechanically-disordered monomer phase in yielding polymers via photo-induced [2 + 2] cycloaddition reaction. Hence, mechanoactivation and amorphization can expand the scope of topochemical polymerization conditions to open up opportunities for generating polymers that are otherwise difficult to synthesize and analyze.
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Affiliation(s)
- Junichi Usuba
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453 USA
| | - Zhenhuan Sun
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453 USA
| | - Han P. Q. Nguyen
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453 USA
| | - Cijil Raju
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453 USA
| | - Klaus Schmidt-Rohr
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453 USA
| | - Grace G. D. Han
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453 USA
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3
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Li F, Li E, Samanta K, Zheng Z, Wu L, Chen AD, Farha OK, Staples RJ, Niu J, Schmidt-Rohr K, Ke C. Ortho-Alkoxy-benzamide Directed Formation of a Single Crystalline Hydrogen-bonded Crosslinked Organic Framework and Its Boron Trifluoride Uptake and Catalysis. Angew Chem Int Ed Engl 2023; 62:e202311601. [PMID: 37870901 DOI: 10.1002/anie.202311601] [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: 08/09/2023] [Revised: 10/23/2023] [Accepted: 10/23/2023] [Indexed: 10/24/2023]
Abstract
Boron trifluoride (BF3 ) is a highly corrosive gas widely used in industry. Confining BF3 in porous materials ensures safe and convenient handling and prevents its degradation. Hence, it is highly desired to develop porous materials with high adsorption capacity, high stability, and resistance to BF3 corrosion. Herein, we designed and synthesized a Lewis basic single-crystalline hydrogen-bond crosslinked organic framework (HC OF-50) for BF3 storage and its application in catalysis. Specifically, we introduced self-complementary ortho-alkoxy-benzamide hydrogen-bonding moieties to direct the formation of highly organized hydrogen-bonded networks, which were subsequently photo-crosslinked to generate HC OFs. The HC OF-50 features Lewis basic thioether linkages and electron-rich pore surfaces for BF3 uptake. As a result, HC OF-50 shows a record-high 14.2 mmol/g BF3 uptake capacity. The BF3 uptake in HC OF-50 is reversible, leading to the slow release of BF3 . We leveraged this property to reduce the undesirable chain transfer and termination in the cationic polymerization of vinyl ethers. Polymers with higher molecular weights and lower polydispersity were generated compared to those synthesized using BF3 ⋅ Et2 O. The elucidation of the structure-property relationship, as provided by the single-crystal X-ray structures, combined with the high BF3 uptake capacity and controlled sorption, highlights the molecular understanding of framework-guest interactions in addressing contemporary challenges.
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Affiliation(s)
- Fangzhou Li
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| | - Errui Li
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| | - Krishanu Samanta
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| | - Zhaoxi Zheng
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
| | - Lianqian Wu
- Department of Chemistry, Boston College, Chestnut Hill, MA 02467, USA
| | - Albert D Chen
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| | - Omar K Farha
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Richard J Staples
- Department of Chemistry, Michigan State University, East Lancing, MI 48824, USA
| | - Jia Niu
- Department of Chemistry, Boston College, Chestnut Hill, MA 02467, USA
| | | | - Chenfeng Ke
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
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4
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Zheng Z, Su Y, Schmidt-Rohr K. Corrected solid-state 13 C nuclear magnetic resonance peak assignment and side-group quantification of hydroxypropyl methylcellulose acetyl succinate pharmaceutical excipients. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:595-605. [PMID: 37649159 DOI: 10.1002/mrc.5390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 09/01/2023]
Abstract
Hydroxypropyl methylcellulose acetyl succinate (HPMCAS) is widely used as a pharmaceutical excipient, making a detailed understanding of its tunable structure important for formulation design. Several recently reported peak assignments in the solid-state 13 C NMR spectrum of HPMCAS have been corrected here using peak integrals in quantitative spectra, spectral editing, empirical chemical-shift predictions based on solution NMR, and full spectrum simulation analogous to deconvolution. Unlike in cellulose, the strong peak at 84 ppm must be assigned to C2 and C3 methyl ethers, instead of regular C4 of cellulose. The proposed assignment of signals at <65 ppm to OCH sites, including C5 of cellulose, could not be confirmed. CH2 spectral editing showed two resolved OCH2 bands, a more intense one from O-CH2 ethers of C6 at >69 ppm and a smaller one from its esters and possibly residual CH2 -OH groups, near 63 ppm. The strong intensities of resolved signals of acetyl, succinoyl, and oxypropyl substituents indicated the substitution of >85% of the OH groups in HPMCAS. The side-group concentrations in three different grades of HPMCAS were quantified.
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Affiliation(s)
- Zhaoxi Zheng
- Department of Chemistry, Brandeis University, Waltham, Massachusetts, USA
| | - Yongchao Su
- Analytical Research and Development, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Klaus Schmidt-Rohr
- Department of Chemistry, Brandeis University, Waltham, Massachusetts, USA
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5
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Gamage J, Voroney P, Gillespie A, Lo A, Longstaffe J. Evidence for the formation of fused aromatic ring structures in an organic soil profile in the early diagenesis. Sci Rep 2023; 13:12378. [PMID: 37524728 PMCID: PMC10390584 DOI: 10.1038/s41598-023-39181-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 07/20/2023] [Indexed: 08/02/2023] Open
Abstract
The presence of fused aromatic ring (FAR) structures in soil define the stability of the recalcitrant soil organic matter (RSOM). FAR are important skeletal features in RSOM that contribute to its extended residence time. During the early diagenesis, FAR structures are formed through condensation and polymerization of biomolecules produced during plant residue and microbial product decay. Molecular level characterization of the RSOM extracted from an organic soil profile gives important insights into the formation of FAR. Advanced solid-state 13C nuclear magnetic resonance (NMR) spectroscopy, including recoupled long-range C-H dipolar dephasing experiments on extracted humic acids (HA) showed that they contain diagenetically formed FAR different from charcoal and lignin. Peaks characteristic of FAR are observed at all depths in the soil profile, with a greater prevalence observed in the HA extracts from the clay soil layer at the bottom. In the clay soil layer, 78% of the aromatic carbon was non-protonated, and this was 2.2-fold higher than the topsoil. These data further strengthen our understanding of the humification process that could occur in early diagenesis and help explain the importance of incorporating diagenesis as an important phenomenon for long-term carbon sequestration in soil.
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Affiliation(s)
- Jeewan Gamage
- School of Environmental Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada.
| | - Paul Voroney
- School of Environmental Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - Adam Gillespie
- School of Environmental Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - Andy Lo
- Advanced Analysis Centre, NMR Centre, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - James Longstaffe
- School of Environmental Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
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Spellman CD, Da'Er S, Ikuma K, Silverman I, Goodwill JE. Sulfite-activated ferrate for water reuse applications. WATER RESEARCH 2022; 216:118317. [PMID: 35339053 DOI: 10.1016/j.watres.2022.118317] [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: 01/10/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
Ferrate is a promising, emerging water treatment technology. However, there has been limited research on the application of ferrate in a water reuse paradigm. Recent literature has shown that ferrate oxidation of target contaminants could be improved by "activation" with the addition of reductants or acid. This study examined the impact of sulfite-activated ferrate in laboratory water matrix and spiked municipal wastewater effluents with the goal of transforming organic contaminants of concern (e.g., 1,4-dioxane) and inactivating pathogenic organisms. Additionally, the formation of brominated disinfection byproducts by activated ferrate were examined and a proposed reaction pathway for byproduct formation is presented. In particular, the relative importance of reaction intermediates is discussed. This represents the first activated ferrate study to examine 1,4-dioxane transformation, disinfection, and brominated byproduct formation. Results presented show that the sub-stoichiometric ([Sulfite]:[Ferrate] = 0.5) activated ferrate treatment approach can oxidize recalcitrant contaminants by >50%, achieve >4-log inactivation of pathogens, and have relatively limited generation of brominated byproducts. However, stoichiometrically excessive ([Sulfite]:[Ferrate] = 4.0) activation showed decreased performance with decreased disinfection and increased risk of by-product formation. In general, our results indicate that sub-stoichiometric sulfite-activated ferrate seems a viable alternative technology for various modes of water reuse treatment.
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Affiliation(s)
- Charles D Spellman
- Department of Civil and Environmental Engineering, University of Rhode Island, Kingston, RI 02881, United States
| | - Sahar Da'Er
- Department of Civil, Construction and Environmental Engineering, Iowa State University, Ames, IA 50011, United States
| | - Kaoru Ikuma
- Department of Civil, Construction and Environmental Engineering, Iowa State University, Ames, IA 50011, United States
| | | | - Joseph E Goodwill
- Department of Civil and Environmental Engineering, University of Rhode Island, Kingston, RI 02881, United States.
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7
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Rudtanatip T, Pariwatthanakun C, Somintara S, Sakeaw W, Wongprasert K. Structural characterization, antioxidant activity, and protective effect against hydrogen peroxide-induced oxidative stress of chemically degraded Gracilaria fisheri sulfated galactans. Int J Biol Macromol 2022; 206:51-63. [PMID: 35218802 DOI: 10.1016/j.ijbiomac.2022.02.125] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 01/22/2022] [Accepted: 02/20/2022] [Indexed: 12/27/2022]
Abstract
Sulfated polysaccharides (SPs) possess an extensive range of biological activities, such as the inhibition of oxidation, correlated with their molecular weight (MW) and chemical structure. In this study, we used the trifluoroacetic acid (TFA) controlled degradation method to degrade sulfated galactans (SG) isolated from Gracilaria fisheri and evaluated the antioxidant and protective effects of the low molecular weight SG (LMSG) against H2O2 on fibroblast cells for the first time. Degradation of native SG (NSG) with an initial MW of 217.45 kDa using different concentrations of TFA resulted in five degraded NSG with MW of 97.23, 62.26, 30.74, 2.63, and 2.59 kDa. The reduction in MW was positively correlated with TFA concentrations. Chemical structure analyses using FTIR and NMR indicated that the TFA degradation process did not significantly change the LMSG polysaccharide main chain but did change the functional groups. LMSG exhibited higher scavenging activities and enhanced the cellular activities of GSH, CAT, and SOD enzymes. Moreover, LMSG activated Nrf-2/ARE signaling and increased expression of antioxidant genes CAT and SOD, which corresponded to increase protective effects against H2O2-induced ROS generation in fibroblast cells. The study reveals modification of NSG by acid TFA degradation resulted in the creation of LMSG, which showed greater antioxidant activity.
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Affiliation(s)
- Tawut Rudtanatip
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kean 40002, Thailand
| | | | - Somsuda Somintara
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kean 40002, Thailand
| | - Waraporn Sakeaw
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kean 40002, Thailand
| | - Kanokpan Wongprasert
- Department of Anatomy, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
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8
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He CS, Ding RR, Chen JQ, Zhou GN, Mu Y. Enhanced reductive reactivity of zero-valent iron (ZVI) for pollutant removal by natural organic matters (NOMs) under aerobic conditions: Correlation between NOM properties and ZVI activity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149812. [PMID: 34455275 DOI: 10.1016/j.scitotenv.2021.149812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/17/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
While ubiquitous natural organic matters (NOMs) are capable of enhancing zero-valent iron (ZVI) performance under aerobic conditions, there is limited understanding of how the properties of NOMs affect the reactivity of ZVI towards contaminants removal. Here, the corresponding activity of ZVI under aerobic conditions was investigated in the presence of humic acid (HA), fulvic acid (FA), bovine serum albumin (BSA). It was found that three models of NOMs were all effective in promoting diatrizoate (DTA) reduction via depassivating ZVI. Interestingly, fast adsorption of NOM onto ZVI surface initially caused inconspicuous impact or visible inhibition on hydrophilic DTA reduction depending on their hydrophobicity. However, subsequent exposure of more reactive sites with high hydrophilicity arising from the detachment of surfaced NOM-associated iron oxide finally contributed to the enhanced consumption of Fe0 with the ability: HA > FA ≈ BSA, and 1-2 times increase in DTA removal kinetic rate following the order: HA > FA > BSA. It further revealed that there were two key factors in determining DTA removal under aerobic conditions, including the ability of NOMs to boost Fe0 consumption as contributed by their aromaticity degree and amino groups, and the hydrophobicity of NOMs to initially affect the property of ZVI surfaces.
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Affiliation(s)
- Chuan-Shu He
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China; Department of Environmental Science and Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Rong-Rong Ding
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jia-Qi Chen
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Guan-Nan Zhou
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Yang Mu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
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9
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Liang T, Zhan ZW, Zou YR. Molecular Simulation of Resin and the Calculation of Molecular Bond Energy. ACS OMEGA 2021; 6:28254-28262. [PMID: 34723022 PMCID: PMC8552466 DOI: 10.1021/acsomega.1c04342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
In this study, average structural characteristics of amber were researched and used as an example to establish the three-dimensional (3D) average structure of resin. Two coal samples containing solid amber were collected from Fushun and Hunchun in Northeast China, from which pure amber samples were separated and resin was extracted. Solid-state nuclear magnetic resonance (13C NMR) spectroscopy was used to obtain structural information of amber, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry was performed on the resins to determine their molecular mass. The results of these studies revealed that the average structure of amber was dominated by cycloalkane, with a small amount of aromatic carbon, and there were almost no aliphatic chains in the structure. The molecular masses of the compounds in the resin were mainly in the range 99-750 Da, and the average molecular mass was ∼370 Da. To characterize the resin chemical structure, two 3D molecular models based on density functional theory were established taking amber as the example, and the relevant molecular bond energies were calculated. Based on these models, the interactions among the components in oil were studied, and the binding energies of the different molecules were calculated. In summary, in this study, amber was used as a medium to establish an accurate molecular model of resin and proved that compared to hydrocarbon compounds, resin molecules were more likely to interact with bitumen.
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Affiliation(s)
- Tian Liang
- State
Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Guangzhou 510640, China
- CAS
Center for Excellence in Deep Earth Science, Guangzhou 510640, China
- University
of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhao-Wen Zhan
- State
Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Guangzhou 510640, China
- CAS
Center for Excellence in Deep Earth Science, Guangzhou 510640, China
| | - Yan-Rong Zou
- State
Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Guangzhou 510640, China
- CAS
Center for Excellence in Deep Earth Science, Guangzhou 510640, China
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10
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Kikuchi J, Yamada S. The exposome paradigm to predict environmental health in terms of systemic homeostasis and resource balance based on NMR data science. RSC Adv 2021; 11:30426-30447. [PMID: 35480260 PMCID: PMC9041152 DOI: 10.1039/d1ra03008f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 08/31/2021] [Indexed: 12/22/2022] Open
Abstract
The environment, from microbial ecosystems to recycled resources, fluctuates dynamically due to many physical, chemical and biological factors, the profile of which reflects changes in overall state, such as environmental illness caused by a collapse of homeostasis. To evaluate and predict environmental health in terms of systemic homeostasis and resource balance, a comprehensive understanding of these factors requires an approach based on the "exposome paradigm", namely the totality of exposure to all substances. Furthermore, in considering sustainable development to meet global population growth, it is important to gain an understanding of both the circulation of biological resources and waste recycling in human society. From this perspective, natural environment, agriculture, aquaculture, wastewater treatment in industry, biomass degradation and biodegradable materials design are at the forefront of current research. In this respect, nuclear magnetic resonance (NMR) offers tremendous advantages in the analysis of samples of molecular complexity, such as crude bio-extracts, intact cells and tissues, fibres, foods, feeds, fertilizers and environmental samples. Here we outline examples to promote an understanding of recent applications of solution-state, solid-state, time-domain NMR and magnetic resonance imaging (MRI) to the complex evaluation of organisms, materials and the environment. We also describe useful databases and informatics tools, as well as machine learning techniques for NMR analysis, demonstrating that NMR data science can be used to evaluate the exposome in both the natural environment and human society towards a sustainable future.
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Affiliation(s)
- Jun Kikuchi
- Environmental Metabolic Analysis Research Team, RIKEN Center for Sustainable Resource Science 1-7-22 Suehiro-cho, Tsurumi-ku Yokohama 230-0045 Japan
- Graduate School of Bioagricultural Sciences, Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8601 Japan
- Graduate School of Medical Life Science, Yokohama City University 1-7-29 Suehiro-cho, Tsurumi-ku Yokohama 230-0045 Japan
| | - Shunji Yamada
- Environmental Metabolic Analysis Research Team, RIKEN Center for Sustainable Resource Science 1-7-22 Suehiro-cho, Tsurumi-ku Yokohama 230-0045 Japan
- Prediction Science Laboratory, RIKEN Cluster for Pioneering Research 7-1-26 Minatojima-minami-machi, Chuo-ku Kobe 650-0047 Japan
- Data Assimilation Research Team, RIKEN Center for Computational Science 7-1-26 Minatojima-minami-machi, Chuo-ku Kobe 650-0047 Japan
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11
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Zachariou A, Hawkins AP, Suwardiyanto, Collier P, Barrow N, Howe RF, Parker SF, Lennon D. New Spectroscopic Insight into the Deactivation of a ZSM‐5 Methanol‐to‐Hydrocarbons Catalyst. ChemCatChem 2021. [DOI: 10.1002/cctc.202100286] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Andrea Zachariou
- School of Chemistry University of Glasgow Joseph Black Building Glasgow G12 8QQ UK
- UK Catalysis Hub Research Complex at Harwell STFC Rutherford Appleton Laboratory Chilton, Oxon OX11 0FA UK
| | - Alexander P. Hawkins
- School of Chemistry University of Glasgow Joseph Black Building Glasgow G12 8QQ UK
- UK Catalysis Hub Research Complex at Harwell STFC Rutherford Appleton Laboratory Chilton, Oxon OX11 0FA UK
| | - Suwardiyanto
- Department of Chemistry University of Jember Jember 68121 East Java Indonesia
| | - Paul Collier
- Johnson Matthey Plc. Johnson Matthey Technology Centre Blounts Court Sonning Common Reading RG4 9NH UK
| | - Nathan Barrow
- Johnson Matthey Plc. Johnson Matthey Technology Centre Blounts Court Sonning Common Reading RG4 9NH UK
| | - Russell F. Howe
- Department of Chemistry University of Aberdeen Meston Building Aberdeen AB24 3UE UK
| | - Stewart F. Parker
- School of Chemistry University of Glasgow Joseph Black Building Glasgow G12 8QQ UK
- UK Catalysis Hub Research Complex at Harwell STFC Rutherford Appleton Laboratory Chilton, Oxon OX11 0FA UK
- ISIS Neutron and Muon Source ISIS Facility STFC Rutherford Appleton Laboratory Chilton, Oxon OX11 0QX UK
| | - David Lennon
- School of Chemistry University of Glasgow Joseph Black Building Glasgow G12 8QQ UK
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12
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Bi Y, Kuzyakov Y, Cai S, Zhao X. Accumulation of organic compounds in paddy soils after biochar application is controlled by iron hydroxides. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 764:144300. [PMID: 33401047 DOI: 10.1016/j.scitotenv.2020.144300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/29/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
Soil acidity is one of the vital factors that influence organic matter transformation and accumulation. Long-term studies on the mechanisms of biochar's effects on soil organic matter (SOM) accumulation dependent on pH values are lacking. A four-year column experiment was conducted without and with biochar application (11.3 Mg ha-1 crop-1) in acid (pH = 5.24) and alkaline (pH = 8.22) soils under paddy rice/wheat annual rotation. To explore organic matter accumulation mechanisms, SOM pools were extracted (physical-chemical fractionation) and their chemical structures were analyzed using advanced solid-state 13C nuclear magnetic resonance (13C NMR) techniques. Biochar increased the proportion of aromatic carbon (C) in all SOM pools, which led to an increased C content in two soils. The elevated pH after biochar application (∆pH = 1.03) increased Fe (III) oxidation and precipitation, and therefore, stimulated amorphous Fe content in 53-μm pool in the acid soil. This change increased the interaction between organic compounds and Fe (hydr)oxide, which impeded bacteria access to substrates, and in turn, promoted SOM accumulation in the acid soil. Conversely, low Fe (hydr)oxide availability resulted in the decomposition of the labile substrates (di-O-alkyl C, NCH, and OCH) in mobile humic acids via microbial respiration, thereby lowering the effect of SOM sequestration in the alkaline soil. Our study revealed that organic matter accumulation after biochar amendment is not solely dependent on the chemical recalcitrance of biochar, but also is controlled by the transformation of Fe (hydr)oxide in SOM pools.
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Affiliation(s)
- Yucui Bi
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, University of Göttingen, Germany; Agro-Technological Institute, RUDN University, 117198 Moscow, Russia
| | - Siyuan Cai
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xu Zhao
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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13
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Song G, Hayes MHB, Novotny EH. A two-year incubation study of transformations of crop residues into soil organic matter (SOM) and a procedure for the sequential isolation and the fractionation of components of SOM. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 763:143034. [PMID: 33139004 DOI: 10.1016/j.scitotenv.2020.143034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 10/09/2020] [Accepted: 10/10/2020] [Indexed: 06/11/2023]
Abstract
Maize (Zea mays) stover, with its natural 13C abundance, was incubated for two years in a gravelly brown earth sandy loam soil that had been under long term cultivation to wheat (Triticum aestivum) for more than 30 years. The relative abundances of 13C in the maize amendment allowed the contributions of the stover to be traced in the components of soil organic matter (SOM) isolated and fractionated using a sequential exhaustive extraction (SEE) process that gave 16 distinct fractions. These were caracterised using elemental, δ13C, FTIR, and 13C NMR analyses. Emphasis is placed on results for two years of incubation but to some extent data are compared with those for similar fractions taken after one year of incubation. Amounts of maize-derived organic carbon in the humic (HA) and fulvic (FA) isolates were more than twice those in the fractions after one year of incubation. The NMR results highlighted compositional differences between the fractions and showed increased contributions of lignin to the HAs and FAs (and especially in the cases of the HAs) as pH increased, and it was evident that humification was taking place after two years of incubation. The most recalcitrant humin fraction, isolated in the final solvent in the sequence, dimethylsulphoxide (DMSO) and sulfuric acid, is composed predominantly of methylene moieties, is compositionally and structurally very different from the humic and hydrophilic isolates, but identical to that which did not dissolve in the solvent. That suggests that exhaustively pre-extracting soil with the NaOH/urea solvent system used will allow a truly representative humin to be obtained using the DMSO/acid solvent system.
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Affiliation(s)
- Guixue Song
- Institute of Marine Science & Technology, Shandong University, Qingdao 266237, China.
| | - Michael H B Hayes
- Department of Chemical Sciences, University of Limerick, Limerick, Ireland.
| | - Etelvino H Novotny
- Embrapa Soils, Rua Jardim Botânico, 1024 CEP 22460-000 Rio de Janeiro, RJ, Brazil
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14
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Podgorski DC, Zito P, Kellerman AM, Bekins BA, Cozzarelli IM, Smith DF, Cao X, Schmidt-Rohr K, Wagner S, Stubbins A, Spencer RGM. Hydrocarbons to carboxyl-rich alicyclic molecules: A continuum model to describe biodegradation of petroleum-derived dissolved organic matter in contaminated groundwater plumes. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123998. [PMID: 33254831 DOI: 10.1016/j.jhazmat.2020.123998] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 08/17/2020] [Accepted: 09/13/2020] [Indexed: 06/12/2023]
Abstract
Relationships between dissolved organic matter (DOM) reactivity and chemical composition in a groundwater plume containing petroleum-derived DOM (DOMHC) were examined by quantitative and qualitative measurements to determine the source and chemical composition of the compounds that persist downgradient. Samples were collected from a transect down the core of the plume in the direction of groundwater flow. An exponential decrease in dissolved organic carbon concentration resulting from biodegradation along the transect correlated with a continuous shift in fluorescent DOMHC from shorter to longer wavelengths. Moreover, ultrahigh resolution mass spectrometry showed a shift from low molecular weight (MW) aliphatic, reduced compounds to high MW, unsaturated (alicyclic/aromatic), high oxygen compounds that are consistent with carboxyl-rich alicyclic molecules. The degree of condensed aromaticity increased downgradient, indicating that compounds with larger, conjugated aromatic core structures were less susceptible to biodegradation. Nuclear magnetic resonance spectroscopy showed a decrease in alkyl (particularly methyl) and an increase in aromatic/olefinic structural motifs. Collectively, data obtained from the combination of these complementary analytical techniques indicated that changes in the DOMHC composition of a groundwater plume are gradual, as relatively low molecular weight (MW), reduced, aliphatic compounds from the oil source were selectively degraded and high MW, alicyclic/aromatic, oxidized compounds persisted.
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Affiliation(s)
- David C Podgorski
- Pontchartrain Institute for Environmental Sciences, Department of Chemistry, Chemical Analysis & Mass Spectrometry Facility, University of New Orleans, New Orleans, LA 70148, USA.
| | - Phoebe Zito
- Pontchartrain Institute for Environmental Sciences, Department of Chemistry, Chemical Analysis & Mass Spectrometry Facility, University of New Orleans, New Orleans, LA 70148, USA
| | - Anne M Kellerman
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL, USA; National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | | | | | - Donald F Smith
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | - Xiaoyan Cao
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
| | | | - Sasha Wagner
- Department of Earth and Environmental Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA; Department of Chemistry and Chemical Biology, Department of Marine and Environmental Sciences, Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, USA
| | - Aron Stubbins
- Department of Chemistry and Chemical Biology, Department of Marine and Environmental Sciences, Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, USA
| | - Robert G M Spencer
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL, USA; National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
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15
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Duan P, Zhi B, Coburn L, Haynes CL, Schmidt-Rohr K. A molecular fluorophore in citric acid/ethylenediamine carbon dots identified and quantified by multinuclear solid-state nuclear magnetic resonance. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2020; 58:1130-1138. [PMID: 31880813 DOI: 10.1002/mrc.4985] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 11/17/2019] [Accepted: 12/16/2019] [Indexed: 06/10/2023]
Abstract
The composition of fluorescent polymer nanoparticles, commonly referred to as carbon dots, synthesized by microwave-assisted reaction of citric acid and ethylenediamine was investigated by 13 C, 13 C{1 H}, 1 H─13 C, 13 C{14 N}, and 15 N solid-state nuclear magnetic resonance (NMR) experiments. 13 C NMR with spectral editing provided no evidence for significant condensed aromatic or diamondoid carbon phases. 15 N NMR showed that the nanoparticle matrix has been polymerized by amide and some imide formation. Five small, resolved 13 C NMR peaks, including an unusual ═CH signal at 84 ppm (1 H chemical shift of 5.8 ppm) and ═CN2 at 155 ppm, and two distinctive 15 N NMR resonances near 80 and 160 ppm proved the presence of 5-oxo-1,2,3,5-tetrahydroimidazo[1,2-a]pyridine-7-carboxylic acid (IPCA) or its derivatives. This molecular fluorophore with conjugated double bonds, formed by a double cyclization reaction of citric acid and ethylenediamine as first shown by Y. Song, B. Yang, and coworkers in 2015, accounts for the fluorescence of the carbon dots. Cross-peaks in a 1 H─13 C HETCOR spectrum with brief 1 H spin diffusion proved that IPCA is finely dispersed in the polyamide matrix. From quantitative 13 C and 15 N NMR spectra, a high concentration (18 ± 2 wt%) of IPCA in the carbon dots was determined. A pronounced gradient in 13 C chemical-shift perturbations and peak widths, with the broadest lines near the COO group of IPCA, indicated at least partial transformation of the carboxylic acid of IPCA by amide or ester formation.
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Affiliation(s)
- Pu Duan
- Department of Chemistry, Brandeis University, Waltham, Massachusetts
| | - Bo Zhi
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota
| | - Luke Coburn
- Department of Chemistry, Brandeis University, Waltham, Massachusetts
| | - Christy L Haynes
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota
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16
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D'Acierno F, Hamad WY, Michal CA, MacLachlan MJ. Thermal Degradation of Cellulose Filaments and Nanocrystals. Biomacromolecules 2020; 21:3374-3386. [PMID: 32705869 DOI: 10.1021/acs.biomac.0c00805] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cellulose-derived materials, such as microcellulose and nanocellulose, are sustainable materials with a wide range of applications. Here, through a multi-analytical approach, we investigate the thermal degradation of microfibrillar cellulose filaments (CFs); acidic cellulose nanocrystals (CNC-H), containing sulfate half-ester groups on the surface; and neutralized cellulose nanocrystals (CNC-Na), where the protons are replaced by sodium ions. CFs have a simple degradation mechanism, associated with extensive dehydration, decarboxylation, and decarbonylation, and the highest thermal stability of the three (∼325 °C) despite the abundance of amorphous regions and inhomogeneous fibrous mass that make them structurally and morphologically less homogeneous than high-crystallinity CNCs. CNC-H decompose in a complex way below 200 °C, with large char fractions and evaporation of sulfur compounds at high temperatures, while sodium counterions in CNC-Na can improve the thermal stability up to 300 °C, where the pyrolysis leads to partial rehydration and formation of sodium hydroxide on the surface.
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Affiliation(s)
- Francesco D'Acierno
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.,Department of Physics and Astronomy, The University of British Columbia, 6224 Agricultural Rd., Vancouver, BC V6T 1Z1, Canada
| | - Wadood Y Hamad
- Transformation and Interfaces Group, Bioproducts Innovation Centre of Excellence, FPInnovations, 2665 East Mall, Vancouver, BC V6T 1Z4, Canada
| | - Carl A Michal
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.,Department of Physics and Astronomy, The University of British Columbia, 6224 Agricultural Rd., Vancouver, BC V6T 1Z1, Canada
| | - Mark J MacLachlan
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
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17
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McKay G. Emerging investigator series: critical review of photophysical models for the optical and photochemical properties of dissolved organic matter. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:1139-1165. [PMID: 32270849 DOI: 10.1039/d0em00056f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Optical measurements (absorbance and fluorescence) are widely used to track dissolved organic matter (DOM) quantity and quality in natural and engineered systems. Despite many decades of research on the optical properties of DOM, there is a lack of understanding with regards to the underlying photophysical model that is the basis for these optical properties. This review both summarizes advances to date on the photophysical properties of DOM and seeks to critically evaluate the photophysical models for DOM optical properties. Recent studies have refined the quantitative understanding of DOM photophysical properties such as excited state lifetimes and energies, rates of different photophysical processes, and quantum yields. Considering fundamental models, more clarity is needed on whether DOM photophysical processes are due to a superposition of non-interacting components (superposition model), or whether a portion of optical signals can be ascribed to electronically interacting moieties, for example in the form of electron donor-acceptor complexes (charge transfer model). Multiple studies over more than two decades have provided evidence for the charge transfer model. Questions have been raised, however, about the broad applicability of the charge transfer model. The charge transfer and superposition model are critically reviewed in light of this current research. Recommendations are given for future studies to help clarify the accuracy of these competing photophysical models.
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Affiliation(s)
- Garrett McKay
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX 77843, USA.
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18
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Yuan S, Duan P, Berthier DL, León G, Sommer H, Saint-Laumer JYD, Schmidt-Rohr K. Multinuclear solid-state NMR of complex nitrogen-rich polymeric microcapsules: Weight fractions, spectral editing, component mixing, and persistent radicals. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 106:101650. [PMID: 32044558 DOI: 10.1016/j.ssnmr.2020.101650] [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: 11/10/2019] [Revised: 01/22/2020] [Accepted: 01/22/2020] [Indexed: 06/10/2023]
Abstract
The molecular structure of a crosslinked nitrogen-rich resin made from melamine, urea, and aldehydes, and of microcapsules made from the reactive resin with multiple polymeric components in aqueous dispersion, has been analyzed by 13C, 13C{1H}, 1H-13C, 1H, 13C{14N}, and 15N solid-state NMR without isotopic enrichment. Quantitative 13C NMR spectra of the microcapsules and three precursor materials enable determination of the fractions of different components. Spectral editing of non-protonated carbons by recoupled dipolar dephasing, of CH by dipolar DEPT, and of C-N by 13C{14N} SPIDER resolves peak overlap and helps with peak assignment. It reveals that the N- and O-rich resin "imitates" the spectrum of polysaccharides such as chitin, cellulose, or Ambergum to an astonishing degree. 15N NMR can distinguish melamine from urea and guanazole, NC=O from COO, and primary from secondary amines. Such a comprehensive and quantitative analysis enables prediction of the elemental composition of the resin, to be compared with combustion analysis for validation. It also provides a reliable reference for iterative simulations of 13C NMR spectra from structural models. The conversion from quantitative NMR peak areas of structural components to the weight fractions of interest in industrial practice is derived and demonstrated. Upon microcapsule formation, 15N and 13C NMR consistently show loss of urea and aldehyde and an increase in primary amines while melamine is retained. NMR also made unexpected findings, such as imbedded crystallites in one of the resins, as well as persistent radicals in the microcapsules. The crystallites produce distinct sharp lines and are distinguished from liquid-like components by their strong dipolar couplings, resulting in fast dipolar dephasing. Fast 1H spin-lattice relaxation on the 35-ms time scale and characteristically non-exponential 13C spin-lattice relaxation indicate persistent radicals, confirmed by EPR. Through 1H spin diffusion, the mixing of components on the 5-nm scale was documented.
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Affiliation(s)
- Shichen Yuan
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA, 02453, USA
| | - Pu Duan
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA, 02453, USA
| | - Damien L Berthier
- Firmenich SA, Corporate Research Division, 1 Routes des Jeunes, 1211, Genève 8, Switzerland
| | - Géraldine León
- Firmenich SA, Corporate Research Division, 1 Routes des Jeunes, 1211, Genève 8, Switzerland
| | - Horst Sommer
- Firmenich SA, Corporate Research Division, 1 Routes des Jeunes, 1211, Genève 8, Switzerland
| | | | - Klaus Schmidt-Rohr
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA, 02453, USA.
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19
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Chen X, Ye X, Chu W, Olk DC, Cao X, Schmidt-Rohr K, Zhang L, Thompson ML, Mao J, Gao H. Formation of Char-Like, Fused-Ring Aromatic Structures from a Nonpyrogenic Pathway during Decomposition of Wheat Straw. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:2607-2614. [PMID: 32096642 DOI: 10.1021/acs.jafc.9b06037] [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] [Indexed: 06/10/2023]
Abstract
Fused-ring aromatics, important skeletal components of black carbon (BC), contribute to long-term carbon (C) sequestration in nature. They have previously been thought to be primarily formed by incomplete combustion of organic materials, whereas the nonpyrogenic origins are negligible. Using advanced solid-state 13C nuclear magnetic resonance (NMR), including recoupled long-range C-H dipolar dephasing, exchange with protonated and nonprotonated spectral editing (EXPANSE), and dipolar-dephased double-quantum/single-quantum (DQ/SQ) spectroscopy, we for the first time identify fused-ring aromatics that formed during the decomposition of wheat (Triticum sp.) straw in soil under aerobic, but not anaerobic conditions. The observed formation of polyaromatic units as plant litter decomposes provides direct evidence for humification. Moreover, the estimation of the annual flux of such nonpyrogenic BC could be equivalent to 3-12% of pyrogenic BC added to soils from all other sources. Our findings significantly extend the understanding of potential sources of fused-ring aromatic C and BC in soils as well as the global C cycle.
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Affiliation(s)
- Xi Chen
- Anhui Province Key Laboratory of Farmland Conservation and Pollution Prevention, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Xinxin Ye
- Anhui Province Key Laboratory of Farmland Conservation and Pollution Prevention, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Wenying Chu
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia 23529, United States
| | - Daniel C Olk
- USDA-ARS, National Laboratory for Agriculture and the Environment, Ames, Iowa 50011, United States
| | - Xiaoyan Cao
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Klaus Schmidt-Rohr
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Ligan Zhang
- Anhui Province Key Laboratory of Farmland Conservation and Pollution Prevention, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Michael L Thompson
- Agronomy Department, Iowa State University, Ames, Iowa 50011, United States
| | - Jingdong Mao
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia 23529, United States
| | - Hongjian Gao
- Anhui Province Key Laboratory of Farmland Conservation and Pollution Prevention, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
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20
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Li W, Wang Z, Xiao M, Miyoshi T, Yang X, Hu Z, Liu C, Chuang SSC, Shawkey MD, Gianneschi NC, Dhinojwala A. Mechanism of UVA Degradation of Synthetic Eumelanin. Biomacromolecules 2019; 20:4593-4601. [DOI: 10.1021/acs.biomac.9b01433] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Weiyao Li
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Zhao Wang
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Ming Xiao
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Toshikazu Miyoshi
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Xiaozhou Yang
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | | | - Cheng Liu
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Steven S. C. Chuang
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Matthew D. Shawkey
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, Ghent 9000, Belgium
| | - Nathan C. Gianneschi
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Ali Dhinojwala
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
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21
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Xu J, Zhao B, Li Z, Chu W, Mao J, Olk DC, Zhang J, Xin X, Wei W. Demonstration of Chemical Distinction among Soil Humic Fractions Using Quantitative Solid-State 13C NMR. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:8107-8118. [PMID: 31260291 DOI: 10.1021/acs.jafc.9b02269] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Humic substances (HS) are vital to soil fertility and carbon sequestration. Using multiple cross-polarization/magic-angle spinning (multiCP/MAS) NMR combined with dipolar dephasing, we quantitatively characterized humic fractions, i.e., fulvic acid (FA), humic acid (HA), and humin (HM), isolated from two representative soils (upland and paddy soils) in China under six long-term (>20 years) fertilizer treatments. Results indicate that each humic fraction showed chemical distinction between the upland and paddy soils, especially with much greater aromaticity of upland HMs than of paddy HMs. Fertilizer treatment exerted greater influence on chemical natures of upland HS than of paddy HS, although the effect was less than that of soil type. Organic manure application especially decreased the percentages of aromatic C in the upland HAs and HMs compared with the control. We concluded that humic fractions responded in chemical nature to environmental conditions, i.e., soil type/cropping system/soil aeration and fertilizer treatments.
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Affiliation(s)
- Jisheng Xu
- State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Science, Chinese Academy of Sciences , Nanjing 210008 , P. R. China
- University of Chinese Academy of Science , Beijing 100049 , P. R. China
| | - Bingzi Zhao
- State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Science, Chinese Academy of Sciences , Nanjing 210008 , P. R. China
| | - Zengqiang Li
- State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Science, Chinese Academy of Sciences , Nanjing 210008 , P. R. China
| | - Wenying Chu
- Department of Chemistry and Biochemistry , Old Dominion University , Norfolk , Virginia 23529 , United States
| | - Jingdong Mao
- Department of Chemistry and Biochemistry , Old Dominion University , Norfolk , Virginia 23529 , United States
| | - Dan C Olk
- USDA-ARS , National Laboratory for Agriculture and the Environment , Ames , Iowa 50011 , United States
| | - Jiabao Zhang
- State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Science, Chinese Academy of Sciences , Nanjing 210008 , P. R. China
| | - Xiuli Xin
- State Key Laboratory of Soil and Sustainable Agriculture , Institute of Soil Science, Chinese Academy of Sciences , Nanjing 210008 , P. R. China
| | - Wenxue Wei
- Institute of Subtropical Agriculture, Chinese Academy of Sciences , No. 1071 Yuandaer Road , Changsha 410125 , P. R. China
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22
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Xiao M, Chen W, Li W, Zhao J, Hong YL, Nishiyama Y, Miyoshi T, Shawkey MD, Dhinojwala A. Elucidation of the hierarchical structure of natural eumelanins. J R Soc Interface 2019. [PMID: 29514988 DOI: 10.1098/rsif.2018.0045] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Eumelanin is one of the most ubiquitous pigments in living organisms and plays an important role in coloration and UV protection. Because eumelanin is highly cross-linked and insoluble in solvents, the chemical structure is still not completely known. In this study, we used atomic force microscopy, X-ray photoelectron spectroscopy and solid-state nuclear magnetic resonance (NMR) to compare intact eumelanosomes (pigment granules mostly made of eumelanin) from four phylogentically distant species: cuttlefish (Sepia officinalis) inks, black fish crow (Corvus ossifragus) feathers, iridescent wild turkey (Melleagris gallopavo) feathers and black human hair. We found that eumelanosomes from all four species are composed of subunit nanoparticles with a length of 10-60 nm, consistent with earlier observations in eumelanosomes from the sepia ink and human hair. The solid-state NMR results indicate the presence of quinone methide tautomers in all four eumelanins. We also found clear differences in the UV absorbance, the ratio of 5,6-dihydroxyindole-2-carboxylic acid/5,6-dihydroxyindole and protonated aryl carbon ratios in sepia eumelanin relative to the other three. This comparison of natural eumelanin across a phylogenetically broad group of organisms provides insights into the change in the eumelanin structure over the evolutionary history and enables the production of synthetic eumelanin with properties that are similar to natural eumelanin.
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Affiliation(s)
- Ming Xiao
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Wei Chen
- State Key Lab of Pollution Control and Resource Reuse Study, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Weiyao Li
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Jiuzhou Zhao
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - You-Lee Hong
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.,RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama 230-0045, Japan
| | - Yusuke Nishiyama
- RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama 230-0045, Japan.,JEOL RESONANCE Inc., Tokyo 196-8558, Japan
| | - Toshikazu Miyoshi
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, Ghent 9000, Belgium
| | - Ali Dhinojwala
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
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23
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Zhou L, Yuan L, Zhao B, Li Y, Lin Z. Structural characteristics of humic acids derived from Chinese weathered coal under different oxidizing conditions. PLoS One 2019; 14:e0217469. [PMID: 31150428 PMCID: PMC6544225 DOI: 10.1371/journal.pone.0217469] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 05/13/2019] [Indexed: 11/18/2022] Open
Abstract
Humic acids derived from Chinese weathered coal were oxidized with hydrogen peroxide (H2O2) under various conditions, and their chemical composition and structure were examined. The raw material humic acids (HA) and oxidized humic acids (OHAs) were characterized by elemental analysis and ultraviolet visible (UV-Vis), Fourier transform infrared (FTIR), and solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Our results show that aromatic functional groups accounted for more than 70% of the HA and OHAs and there were significant differences in their structures and compositions. Compared to the HA, the average H and N contents of the OHAs decreased by 5.15% and 2.52%, respectively, and the average O content of those of the OHAs increased by 5.30%. The hydrophobicity index (HI) of HA is higher than those of the OHAs. Importantly, in the hypothesis test between the properties and preparation conditions of humic acid using SPSS, the partial η2 of the temperature, hydrogen peroxide concentration, liquid-solid ratio, and time were 0.809, 0.771, 0.748 and 0.729, respectively; thus, among the preparation conditions, temperature is the most important factor affecting the humic acids properties.
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Affiliation(s)
- Liping Zhou
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture and Rural Affairs / Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Liang Yuan
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture and Rural Affairs / Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Bingqiang Zhao
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture and Rural Affairs / Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
- * E-mail:
| | - Yanting Li
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture and Rural Affairs / Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhian Lin
- Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture and Rural Affairs / Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
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24
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Fritzsching KJ, Duan P, Alberts EM, Tibabuzo Perdomo AM, Kenny P, Wilker JJ, Schmidt-Rohr K. Silk-Like Protein with Persistent Radicals Identified in Oyster Adhesive by Solid-State NMR. ACS APPLIED BIO MATERIALS 2019; 2:2840-2852. [DOI: 10.1021/acsabm.9b00243] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Keith J. Fritzsching
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Pu Duan
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | | | | | - Paul Kenny
- Baruch Marine Field Laboratory, University of South Carolina, P.O. Box 1630, Georgetown, South Carolina 29442, United States
| | | | - Klaus Schmidt-Rohr
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
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25
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Yao SH, Zhang YL, Han Y, Han XZ, Mao JD, Zhang B. Labile and recalcitrant components of organic matter of a Mollisol changed with land use and plant litter management: An advanced 13C NMR study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 660:1-10. [PMID: 30634126 DOI: 10.1016/j.scitotenv.2018.12.403] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/26/2018] [Accepted: 12/26/2018] [Indexed: 06/09/2023]
Abstract
Soil organic matter (SOM) changes with land use and soil management, yet the controlling factors over the chemical composition of SOM are not fully understood. We applied quantitative 13C nuclear magnetic resonance and spectral editing techniques to measure chemical structures of SOM from different land use types. The land use types included a native grassland (nGL), a crop land with straw burning in the field (bCL), a restored grassland (rGL) and a cropland with straw removed out of the field (rCL) for 28years. The abundances of OCH groups from carbohydrates were higher in the SOMs of the nGL and rGL than in those of the rCL and bCL, while the abundances of OCH3 and aromatic CO groups from lignin were higher in the SOMs of the three-ever cultivated lands (rGL, rCL and bCL) than in that of the nGL. Although aromatic CC groups were most dominant in the Mollisols, they did not consistently decrease after the burnings of straw were ceased in the fields of the rCL and rGL compared to the bCL with continuous burning. In addition, the COO groups were bound with the aromatic CC groups in all the land use types, and the sizes of the aromatic clusters were affected by the land use types. The labile and recalcitrant components were correlated with SOC contents the mineral-associated and particular SOM in a contrasting way. Our results suggested that the chemical composition of SOM in the Mollisol depended on land use types, and that labile and recalcitrant components might be protected through mineral associations and aggregation, respectively. The most abundant aromatics in the Mollisols might not just be pyrogenic and could be oxidized to different extents, depending on field drainage conditions.
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Affiliation(s)
- Shui-Hong Yao
- National Engineering Laboratory for Improving Fertility of Arable Soils, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Yue-Ling Zhang
- National Engineering Laboratory for Improving Fertility of Arable Soils, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Ya Han
- National Engineering Laboratory for Improving Fertility of Arable Soils, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Xiao-Zeng Han
- Key Laboratory of Mollisols Agroecology, National Field Observation and Research Station of Hailun Agroecosystems, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin 150081, PR China
| | - Jing-Dong Mao
- Department of Chemistry and Biochemistry, Old Dominion University, 4541 Hampton Blvd, Norfolk, VA 23529, USA
| | - Bin Zhang
- National Engineering Laboratory for Improving Fertility of Arable Soils, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
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Chen Z, Droste J, Zhai G, Zhu J, Yang J, Hansen MR, Zhuang X. Sulfur-anchored azulene as a cathode material for Li–S batteries. Chem Commun (Camb) 2019; 55:9047-9050. [DOI: 10.1039/c9cc04413b] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A benzene-free and vinyl-free molecule, azulene, is used to polymerize with sulfur for new cathode material based Li–S batteries.
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Affiliation(s)
- Zhenying Chen
- The Soft2D Lab
- State Key Laboratory of Metal Matrix Composites & Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
| | - Jörn Droste
- Institute for Physical Chemistry
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Guangqun Zhai
- Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials
- School of Materials Science and Engineering
- Changzhou University
- Changzhou 213164
- China
| | - Jinhui Zhu
- The Soft2D Lab
- State Key Laboratory of Metal Matrix Composites & Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
| | - Jun Yang
- The Soft2D Lab
- State Key Laboratory of Metal Matrix Composites & Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
| | - Michael Ryan Hansen
- Institute for Physical Chemistry
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Xiaodong Zhuang
- The Soft2D Lab
- State Key Laboratory of Metal Matrix Composites & Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
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27
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Li FS, Phyo P, Jacobowitz J, Hong M, Weng JK. The molecular structure of plant sporopollenin. NATURE PLANTS 2019; 5:41-46. [PMID: 30559416 DOI: 10.1038/s41477-018-0330-7] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 11/15/2018] [Indexed: 05/22/2023]
Abstract
Sporopollenin is a ubiquitous and extremely chemically inert biopolymer that constitutes the outer wall of all land-plant spores and pollen grains1. Sporopollenin protects the vulnerable plant gametes against a wide range of environmental assaults, and is considered a prerequisite for the migration of early plants onto land2. Despite its importance, the chemical structure of plant sporopollenin has remained elusive1. Using a newly developed thioacidolysis degradative method together with state-of-the-art solid-state NMR techniques, we determined the detailed molecular structure of pine sporopollenin. We show that pine sporopollenin is primarily composed of aliphatic-polyketide-derived polyvinyl alcohol units and 7-O-p-coumaroylated C16 aliphatic units, crosslinked through a distinctive dioxane moiety featuring an acetal. Naringenin was also identified as a minor component of pine sporopollenin. This discovery answers the long-standing question about the chemical make-up of plant sporopollenin, laying the foundation for future investigations of sporopollenin biosynthesis and for the design of new biomimetic polymers with desirable inert properties.
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Affiliation(s)
- Fu-Shuang Li
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Pyae Phyo
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joseph Jacobowitz
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jing-Ke Weng
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
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28
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Li FS, Phyo P, Jacobowitz J, Hong M, Weng JK. The molecular structure of plant sporopollenin. NATURE PLANTS 2019. [PMID: 30559416 DOI: 10.1038/s41477-018-0330-337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Sporopollenin is a ubiquitous and extremely chemically inert biopolymer that constitutes the outer wall of all land-plant spores and pollen grains1. Sporopollenin protects the vulnerable plant gametes against a wide range of environmental assaults, and is considered a prerequisite for the migration of early plants onto land2. Despite its importance, the chemical structure of plant sporopollenin has remained elusive1. Using a newly developed thioacidolysis degradative method together with state-of-the-art solid-state NMR techniques, we determined the detailed molecular structure of pine sporopollenin. We show that pine sporopollenin is primarily composed of aliphatic-polyketide-derived polyvinyl alcohol units and 7-O-p-coumaroylated C16 aliphatic units, crosslinked through a distinctive dioxane moiety featuring an acetal. Naringenin was also identified as a minor component of pine sporopollenin. This discovery answers the long-standing question about the chemical make-up of plant sporopollenin, laying the foundation for future investigations of sporopollenin biosynthesis and for the design of new biomimetic polymers with desirable inert properties.
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Affiliation(s)
- Fu-Shuang Li
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Pyae Phyo
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joseph Jacobowitz
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jing-Ke Weng
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
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29
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Agrawal V, Sharma S. Improved Kerogen Models for Determining Thermal Maturity and Hydrocarbon Potential of Shale. Sci Rep 2018; 8:17465. [PMID: 30504862 PMCID: PMC6269451 DOI: 10.1038/s41598-018-35560-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 11/07/2018] [Indexed: 11/09/2022] Open
Abstract
Kerogen is the insoluble component of organic-rich shales that controls the type and amount of hydrocarbons generated in conventional and unconventional reservoirs. Significant progress has recently been made in developing structural models of kerogen. However, there is still a large gap in understanding the evolution of the molecular components of kerogen with thermal maturation and their hydrocarbon (HC) generative potential. Here, we determine the variations in different molecular fragments of kerogen from a Marcellus Shale maturity series (with VRo ranging from 0.8 to 3) using quantitative 13C MultiCP/MAS NMR and MultiCP NMR/DD (dipolar dephasing). These molecular variations provide insight into the (1) evolution of the molecular structure of kerogen with increasing thermal maturity and, (2) the primary molecular contributors to HC generation. Our results also indicate that old model equations based on structural parameters of kerogen underestimate the thermal maturity and overestimate the HC generation potential of Marcellus Shale samples. This could primarily be due to the fact that the kerogen samples used to reconstruct old models were mostly derived from immature shales (VRo <1) acquired from different basins with varying depositional environments. We utilized the kerogen molecular parameters determined from the Marcellus maturity series samples to develop improved models for determining thermal maturity and HC potential of Marcellus Shale. The models generated in this study could also potentially be applied to other shales of similar maturity range and paleo-depositional environments.
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Affiliation(s)
- Vikas Agrawal
- Department of Geology and Geography, West Virginia University, Morgantown, WV, United States
| | - Shikha Sharma
- Department of Geology and Geography, West Virginia University, Morgantown, WV, United States.
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30
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Shikhov I, Thomas DS, Rawal A, Yao Y, Gizatullin B, Hook JM, Stapf S, Arns CH. Application of low-field, 1H/ 13C high-field solution and solid state NMR for characterisation of oil fractions responsible for wettability change in sandstones. Magn Reson Imaging 2018; 56:77-85. [PMID: 30316982 DOI: 10.1016/j.mri.2018.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/05/2018] [Accepted: 10/06/2018] [Indexed: 11/18/2022]
Abstract
Asphaltene adsorption on solid surfaces is a standing problem in petroleum industry. It has an adverse effect on reservoir production and development by changing rock wettability, plugging pore throats, and affects oil transport through pipelines. Asphaltene chemistry constitutes important part of the ageing process as part of petrophysical studies and core analysis. The mechanisms and contribution of various oil components to adsorption processes is not fully understood. To investigate the kinetics of the ageing process and address the relative contribution of different oil components, we prepared three sets of sandstone core plugs aged in different oil mixtures over various time intervals. Cores were then re-saturated with decane to evaluate their wetting state using low-field NMR relaxometry by monitoring a change of surface relaxivity. Adsorbed deposits were then extracted from cores for solution-state NMR analysis. Their 1H and 1H-13C correlation spectra obtained using heteronuclear single quantum coherence (HSQC) technique were matched to spectra of four SARA (saturates, aromatics, resins and asphaltenes) components of oil mixtures to deduce components of deposits and inter-component interactions. We notice that wettability reversal of rock is inversely proportional to initial asphaltene concentration. Analysis of deposits reveals an increase in their aliphatic content over ageing time, which is accompanied by a change of the morphology of the pore space due to cluster aggregates forming a network. Results suggest that the ageing process in respect to the wetting state of rock samples consists of three distinctive stages: (i) an early-time period, when the fraction of most polar asphaltenes creates a discontinuous layer corresponding to mixed-wet state; (ii) an intermediate-time interval, at which the full grain coverage may be achieved (at favourable chemical environment) corresponding to strong oil-wetting; (iii) a late-time stage, where intense macro-aggregates accumulation occurs, changing the pore space integrity. It is likely asphaltene-aliphatic interactions leading to growth of sub-micron size macro-aggregates.
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Affiliation(s)
- Igor Shikhov
- School of Mineral and Energy Resources Engineering, The University of New South Wales, Sydney, 2052 NSW, Australia.
| | - Donald S Thomas
- Nuclear Magnetic Resonance Facility, UNSW Mark Wainwright Analytical Centre, Sydney, 2052 NSW, Australia
| | - Aditya Rawal
- Nuclear Magnetic Resonance Facility, UNSW Mark Wainwright Analytical Centre, Sydney, 2052 NSW, Australia
| | - Yin Yao
- Electron Microscopy Unit, UNSW Mark Wainwright Analytical Centre, Sydney, 2052 NSW, Australia
| | - Bulat Gizatullin
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| | - James M Hook
- Nuclear Magnetic Resonance Facility, UNSW Mark Wainwright Analytical Centre, Sydney, 2052 NSW, Australia
| | - Siegfried Stapf
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| | - Christoph H Arns
- School of Mineral and Energy Resources Engineering, The University of New South Wales, Sydney, 2052 NSW, Australia
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31
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Protective Carbon Overlayers from 2,3-Naphthalenediol Pyrolysis on Mesoporous SiO₂ and Al₂O₃ Analyzed by Solid-State NMR. MATERIALS 2018; 11:ma11060980. [PMID: 29890759 PMCID: PMC6025365 DOI: 10.3390/ma11060980] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/01/2018] [Accepted: 06/05/2018] [Indexed: 11/28/2022]
Abstract
Hydrothermally stable carbon overlayers can protect mesoporous oxides (SiO2 and Al2O3) from hydrolysis during aqueous-phase catalysis. Overlayers made at 800 °C by pyrolysis of 2,3-naphthalenediol deposited out of acetone solution were analyzed by solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Power absorption due to sample conductivity was prevented by diluting the sample in nonconductive and background-free tricalcium phosphate. While pyrolysis on SiO2 produced a predominantly aromatic carbon film, at least 15% of nonaromatic carbon (sp3-hybridized C as well as C=O) was observed on γ-Al2O3. These species were not derived from residual solvent, according to spectra of the same material treated at 400 °C. The sp3-hybridized C exhibited weak couplings to hydrogen, short spin-lattice relaxation times, and unusually large shift anisotropies, which are characteristics of tetrahedral carbon with high concentrations of unpaired electrons. Moderate heat treatment at 400 °C on SiO2 and Al2O3 resulted in yellow-brown and nearly black samples, respectively, but the darker color on Al2O3 did not correspond to more extensive carbonization. Aromatic carbon bonded to hydrogen remained predominant and the peaks of naphthalenediol were still recognizable; however, some of the chemical shifts differed by up to 5 ppm, indicating significant differences in local structure. On SiO2, additional sharp peaks were detected and attributed to 1/3 of the 2,3-naphthalene molecules undergoing fast, nearly isotropic motions.
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Duan P, Li X, Wang T, Chen B, Juhl SJ, Koeplinger D, Crespi VH, Badding JV, Schmidt-Rohr K. The Chemical Structure of Carbon Nanothreads Analyzed by Advanced Solid-State NMR. J Am Chem Soc 2018; 140:7658-7666. [PMID: 29808673 DOI: 10.1021/jacs.8b03733] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Carbon nanothreads are a new type of one-dimensional sp3-carbon nanomaterial formed by slow compression and decompression of benzene. We report characterization of the chemical structure of 13C-enriched nanothreads by advanced quantitative, selective, and two-dimensional solid-state nuclear magnetic resonance (NMR) experiments complemented by infrared (IR) spectroscopy. The width of the NMR spectral peaks suggests that the nanothread reaction products are much more organized than amorphous carbon. In addition, there is no evidence from NMR of a second phase such as amorphous mixed sp2/sp3-carbon. Spectral editing reveals that almost all carbon atoms are bonded to one hydrogen atom, unlike in amorphous carbon but as is expected for enumerated nanothread structures. Characterization of the local bonding structure confirms the presence of pure fully saturated "degree-6" carbon nanothreads previously deduced on the basis of crystal packing considerations from diffraction and transmission electron microscopy. These fully saturated threads comprise between 20% and 45% of the sample. Furthermore, 13C-13C spin exchange experiments indicate that the length of the fully saturated regions of the threads exceeds 2.5 nm. Two-dimensional 13C-13C NMR spectra showing bonding between chemically nonequivalent sites rule out enumerated single-site thread structures such as polytwistane or tube (3,0) but are consistent with multisite degree-6 nanothreads. Approximately a third of the carbon is in "degree-4" nanothreads with isolated double bonds. The presence of doubly unsaturated degree-2 benzene polymers can be ruled out on the basis of 13C-13C NMR with spin exchange rate constants tuned by rotational resonance and 1H decoupling. A small fraction of the sample consists of aromatic rings within the threads that link sections with mostly saturated bonding. NMR provides the detailed bonding information necessary to refine solid-state organic synthesis techniques to produce pure degree-6 or degree-4 carbon nanothreads.
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Affiliation(s)
- Pu Duan
- Department of Chemistry , Brandeis University , Waltham , Massachusetts 02453 , United States
| | | | | | - Bo Chen
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States
| | | | | | | | | | - Klaus Schmidt-Rohr
- Department of Chemistry , Brandeis University , Waltham , Massachusetts 02453 , United States
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33
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Concepts and Misconceptions of Humic Substances as the Stable Part of Soil Organic Matter: A Review. AGRONOMY-BASEL 2018. [DOI: 10.3390/agronomy8050076] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Kikuchi J, Ito K, Date Y. Environmental metabolomics with data science for investigating ecosystem homeostasis. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 104:56-88. [PMID: 29405981 DOI: 10.1016/j.pnmrs.2017.11.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 11/19/2017] [Accepted: 11/19/2017] [Indexed: 05/08/2023]
Abstract
A natural ecosystem can be viewed as the interconnections between complex metabolic reactions and environments. Humans, a part of these ecosystems, and their activities strongly affect the environments. To account for human effects within ecosystems, understanding what benefits humans receive by facilitating the maintenance of environmental homeostasis is important. This review describes recent applications of several NMR approaches to the evaluation of environmental homeostasis by metabolic profiling and data science. The basic NMR strategy used to evaluate homeostasis using big data collection is similar to that used in human health studies. Sophisticated metabolomic approaches (metabolic profiling) are widely reported in the literature. Further challenges include the analysis of complex macromolecular structures, and of the compositions and interactions of plant biomass, soil humic substances, and aqueous particulate organic matter. To support the study of these topics, we also discuss sample preparation techniques and solid-state NMR approaches. Because NMR approaches can produce a number of data with high reproducibility and inter-institution compatibility, further analysis of such data using machine learning approaches is often worthwhile. We also describe methods for data pretreatment in solid-state NMR and for environmental feature extraction from heterogeneously-measured spectroscopic data by machine learning approaches.
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Affiliation(s)
- Jun Kikuchi
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Graduate School of Bioagricultural Sciences, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya, Aichi 464-0810, Japan.
| | - Kengo Ito
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Yasuhiro Date
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
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35
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Huo J, Duan P, Pham HN, Chan YJ, Datye AK, Schmidt-Rohr K, Shanks BH. Improved hydrothermal stability of Pd nanoparticles on nitrogen-doped carbon supports. Catal Sci Technol 2018. [DOI: 10.1039/c8cy00947c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Carbon supports have been shown to provide better hydrothermal stability than alumina or silica supports, thus attracting more attention for aqueous-phase biomass conversion reactions.
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Affiliation(s)
- Jiajie Huo
- Department of Chemical and Biological Engineering
- Ames
- USA
- Center for Biorenewable Chemicals
- Iowa State University
| | - Pu Duan
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemistry
| | - Hien N. Pham
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemical and Biological Engineering and Center for Microengineered Materials
| | - Yee Jher Chan
- Department of Chemical and Biological Engineering
- Ames
- USA
| | - Abhaya K. Datye
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemical and Biological Engineering and Center for Microengineered Materials
| | - Klaus Schmidt-Rohr
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemistry
| | - Brent H. Shanks
- Department of Chemical and Biological Engineering
- Ames
- USA
- Center for Biorenewable Chemicals
- Iowa State University
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36
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Huo J, Johnson RL, Duan P, Pham HN, Mendivelso-Perez D, Smith EA, Datye AK, Schmidt-Rohr K, Shanks BH. Stability of Pd nanoparticles on carbon-coated supports under hydrothermal conditions. Catal Sci Technol 2018. [DOI: 10.1039/c7cy02098h] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrothermal stability is one of the major challenges facing heterogeneous catalysis in biomass conversion to chemicals or fuels.
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Affiliation(s)
- Jiajie Huo
- Department of Chemical and Biological Engineering
- Ames
- USA
- Center for Biorenewable Chemicals
- Iowa State University
| | - Robert L. Johnson
- Department of Chemical and Biological Engineering
- Ames
- USA
- Center for Biorenewable Chemicals
- Iowa State University
| | - Pu Duan
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemistry
| | - Hien N. Pham
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemical and Biological Engineering
| | - Deyny Mendivelso-Perez
- Ames Laboratory
- U.S. Department of Energy
- Department of Chemistry
- Iowa State University
- Ames
| | - Emily A. Smith
- Ames Laboratory
- U.S. Department of Energy
- Department of Chemistry
- Iowa State University
- Ames
| | - Abhaya K. Datye
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemical and Biological Engineering
| | - Klaus Schmidt-Rohr
- Center for Biorenewable Chemicals
- Iowa State University
- Ames
- USA
- Department of Chemistry
| | - Brent H. Shanks
- Department of Chemical and Biological Engineering
- Ames
- USA
- Center for Biorenewable Chemicals
- Iowa State University
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37
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Xu J, Zhao B, Chu W, Mao J, Olk DC, Xin X, Zhang J. Altered humin compositions under organic and inorganic fertilization on an intensively cultivated sandy loam soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 601-602:356-364. [PMID: 28570970 DOI: 10.1016/j.scitotenv.2017.05.205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 05/22/2017] [Accepted: 05/23/2017] [Indexed: 06/07/2023]
Abstract
Humin is the most recalcitrant fraction of soil organic matter (SOM). However, little is known about quantitative structural information on humin and the roles of soil mircoorganisms involved in the humin formation. We applied advanced solid-state 13C nuclear magnetic resonance (NMR) spectroscopy to provide deep insights into humin structural changes in response to long-term balanced fertilization on a Calcaric Fluvisol in the North China plain. The relationships between humin structure and microbiological properties such as microbial biomass, microbial quotient (qmic) and metabolic quotient (qCO2) were also studied. The humins had a considerable (35-44%) proportion of aromatic C being nonprotonated and the vast majority of O-alkyl and anomeric C being protonated. Alkyl (24-27% of all C), aromatic C (17-28%) and O-alkyl (13-20%) predominated in humins. Long-term fertilization promoted the aliphatic nature of humins, causing increases in O-alkyl, anomeric and NCH functional groups and decreases in aromatic C and aromatic CO groups. All these changes were more prominent for treatments of organic fertilizer (OF) and combined mineral NPK fertilizer with OF (NPKOF) relative to the Control and NPK treatments. Fertilization also decreased the alkyl/O-alkyl ratio, aromaticity and hydrophobic characteristics of humins, suggesting a more decomposed and humified state of humin in the Control soil. Moreover, the soil microbiological properties had strong correlations with functional groups of humins. Particularly, microbial biomass C was a relatively sensitive indicator, having positive correlations with oxygen-containing functional groups, i.e., COO/NCO and protonated O-alkyl C, and negative correlations with nonprotonated aromatic C. The qmic and qCO2 were also significantly positively correlated with NCH and aromatic CO, respectively. Our results deepen our understanding of how long-term fertilization impacts the structure of humin, and highlight a linkage between microbiological properties and recalcitrant fraction of SOM besides labile fraction.
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Affiliation(s)
- Jisheng Xu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Science, Beijing 100049, China
| | - Bingzi Zhao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Wenying Chu
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, United States
| | - Jingdong Mao
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, United States
| | - Dan C Olk
- USDA-ARS, National Laboratory for Agriculture and the Environment, Ames, IA 50011, USA
| | - Xiuli Xin
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Jiabao Zhang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
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Duan P, Schmidt-Rohr K. Composite-pulse and partially dipolar dephased multiCP for improved quantitative solid-state 13C NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 285:68-78. [PMID: 29121512 DOI: 10.1016/j.jmr.2017.10.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 10/22/2017] [Accepted: 10/24/2017] [Indexed: 05/22/2023]
Abstract
Improved multiple cross polarization (multiCP) pulse sequences for quickly acquiring quantitative 13C NMR spectra of organic solids are presented. Loss of 13C magnetization due to imperfect read-out and storage pulses in multiCP has been identified as a significant mechanism limiting polarization enhancement for 13C sites with weak couplings to 1H. This problem can be greatly reduced by composite 90° pulses with non-orthogonal phases that flip the magnetization onto the spin-lock field and back to the longitudinal direction for the 1H repolarization period; the observed loss is <3% for over ±10 kHz resonance offset and up to 20% flip-angle error. This composite-pulse multiCP (ComPmultiCP) sequence consistently provides performance superior to that of conventional multiCP, without any trade-off. The longer total CP time enabled by the composite pulses allows for a wider amplitude ramp during CP, which decreases the sensitivity to Hartmann-Hahn mismatch by a factor of two, with a <7% root-mean-square deviation within a 1-dB range for Boc-alanine. In samples with very short T1ρ, under-polarization of non-protonated carbons can be compensated by slight dipolar dephasing of CHn signals resulting from relatively weak decoupling during the Hahn spin echo period before detection. Quantitative spectra have been obtained by ComPmultiCP for low-crystallinity branched polyethylene at 4.5 kHz MAS, and in combination with partial dipolar dephasing for soil organic matter at 14 kHz MAS.
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Affiliation(s)
- Pu Duan
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
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Huang J, Yu Z, Gao H, Yan X, Chang J, Wang C, Hu J, Zhang L. Chemical structures and characteristics of animal manures and composts during composting and assessment of maturity indices. PLoS One 2017; 12:e0178110. [PMID: 28604783 PMCID: PMC5467826 DOI: 10.1371/journal.pone.0178110] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 05/06/2017] [Indexed: 11/19/2022] Open
Abstract
Changes in physicochemical characteristics, chemical structures and maturity of swine, cattle and chicken manures and composts during 70-day composting without addition of bulking agents were investigated. Physicochemical characteristics were measured by routine analyses and chemical structures by solid-state 13C NMR and FT-IR. Three manures were of distinct properties. Their changes in physicochemical characteristics, chemical structures, and maturity were different not only from each other but also from those with addition of bulking agents during composting. Aromaticity in chicken manure composts decreased at first, and then increased whereas that in cattle and swine manure composts increased. Enhanced ammonia volatilization occurred without addition of bulking agents. NMR structural information indicated that cattle and chicken composts were relatively stable at day 36 and 56, respectively, but swine manure composts were not mature up to day 70. Finally, the days required for three manures to reach the threshold values of different maturity indices were different.
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Affiliation(s)
- Jieying Huang
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, Hefei, Anhui, People’s Republic of China
| | - Zixuan Yu
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China
| | - Hongjian Gao
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, Hefei, Anhui, People’s Republic of China
| | - Xiaoming Yan
- Institute of Agro-Products Processing Science and Technology, Anhui Academy of Agricultural Sciences, Hefei, Anhui, People’s Republic of China
| | - Jiang Chang
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China
| | - Chengming Wang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China
| | - Jingwei Hu
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China
| | - Ligan Zhang
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, Hefei, Anhui, People’s Republic of China
- * E-mail:
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Mao J, Cao X, Olk DC, Chu W, Schmidt-Rohr K. Advanced solid-state NMR spectroscopy of natural organic matter. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2017; 100:17-51. [PMID: 28552171 DOI: 10.1016/j.pnmrs.2016.11.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 11/15/2016] [Accepted: 11/28/2016] [Indexed: 06/07/2023]
Abstract
Solid-state NMR is essential for the characterization of natural organic matter (NOM) and is gaining importance in geosciences and environmental sciences. This review is intended to highlight advanced solid-state NMR techniques, especially a systematic approach to NOM characterization, and their applications to the study of NOM. We discuss some basics of how to acquire high-quality and quantitative solid-state 13C NMR spectra, and address some common technical mistakes that lead to unreliable spectra of NOM. The identification of specific functional groups in NOM, primarily based on 13C spectral-editing techniques, is described and the theoretical background of some recently-developed spectral-editing techniques is provided. Applications of solid-state NMR to investigating nitrogen (N) in NOM are described, focusing on limitations of the widely used 15N CP/MAS experiment and the potential of improved advanced NMR techniques for characterizing N forms in NOM. Then techniques used for identifying proximities, heterogeneities and domains are reviewed, and some examples provided. In addition, NMR techniques for studying segmental dynamics in NOM are reviewed. We also briefly discuss applications of solid-state NMR to NOM from various sources, including soil organic matter, aquatic organic matter, organic matter in atmospheric particulate matter, carbonaceous meteoritic organic matter, and fossil fuels. Finally, examples of NMR-based structural models and an outlook are provided.
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Affiliation(s)
- Jingdong Mao
- Department of Chemistry and Biochemistry, Old Dominion University, 4541 Hampton Blvd., Norfolk, VA 23529, United States.
| | - Xiaoyan Cao
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, United States.
| | - Dan C Olk
- National Laboratory for Agriculture and the Environment, 1015 N. University Blvd., Ames, IA 50011, United States.
| | - Wenying Chu
- Department of Chemistry and Biochemistry, Old Dominion University, 4541 Hampton Blvd., Norfolk, VA 23529, United States.
| | - Klaus Schmidt-Rohr
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, United States.
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Miller JJ, Beasley BW, Hazendonk P, Drury CF, Chanasyk DS. Influence of Long-term Application of Feedlot Manure Amendments on Water Repellency of a Clay Loam Soil. JOURNAL OF ENVIRONMENTAL QUALITY 2017; 46:667-675. [PMID: 28724097 DOI: 10.2134/jeq2017.02.0074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Long-term application of feedlot manure to cropland may increase the quantity of soil organic carbon (C) and change its quality, which may influence soil water repellency. The objective was to determine the influence of feedlot manure type (stockpiled vs. composted), bedding material (straw [ST] vs. woodchips [WD]), and application rate (13, 39, or 77 Mg ha) on repellency of a clay loam soil after 17 annual applications. The repellency was determined on all 14 treatments using the water repellency index ( index), the water drop penetration time (WDPT) method, and molarity of ethanol (MED) test. The C composition of particulate organic matter in soil of five selected treatments after 16 annual applications was also determined using C nuclear magnetic resonance-direct polarization with magic-angle spinning (NMR-DPMAS). Manure type had no significant ( > 0.05) effect on index and WDPT, and MED classification was similar. Mean index and WDPT values were significantly greater and MED classification more hydrophobic for WD than ST. Application rate had no effect on the index, but WDPT was significantly greater and MED classification more hydrophobic with increasing application rate. Strong ( > 0.7) but nonsignificant positive correlations were found between index and WDPT versus hydrophobic (alkyl + aromatic) C, lignin at 74 ppm (O-alkyl), and unspecified aromatic compounds at 144 ppm. Specific aromatic compounds also contributed more to repellency than alkyl, O-alkyl, and carbonyl compounds. Overall, all three methods consistently showed that repellency was greater for WD- than ST-amended clay loam soil, but manure type had no effect.
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Xu J, Zhao B, Chu W, Mao J, Zhang J. Chemical nature of humic substances in two typical Chinese soils (upland vs paddy soil): A comparative advanced solid state NMR study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 576:444-452. [PMID: 27792959 DOI: 10.1016/j.scitotenv.2016.10.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 10/11/2016] [Accepted: 10/17/2016] [Indexed: 06/06/2023]
Abstract
Knowledge of the structural features of humic substances (HSs) is essential for elucidating the mechanisms of humification in different soil environments and realizing their profound roles in environmental issues. The aim of this work was to investigate the chemical structures of fulvic acid (FA), humic acid (HA) and humin (HM) fractions isolated from an upland soil (Fluvisol) and a paddy soil (Anthrosol) typical in China using advanced solid-state 13C nuclear magnetic resonance (NMR) techniques. The results revealed that there were great structural differences of HSs between the two soils. The two FAs showed distinct quantitative differences in aliphatics with more polysaccharides in the FA from the upland soil than from the paddy soil. The HM from the upland soil differed from the paddy soil HM in having more proteins/peptides (23% vs 20%), total aromatics (21% vs 12%) as well as fewer lipids (24% vs 35%) and polysaccharides (27% vs 31%). The HM fractions represented the most different components of organic matter between the two soils. The degree of difference between the two HAs fell in between that of FAs and HM fractions. In particular, the HA from the upland soil had relatively greater degree of aromaticity. Our study indicated that the upland soil exhibited a higher degree of humification compared with the paddy soil. Among the three humic fractions, the FAs featured COO/N-CO groups, and the HAs were more enriched in protonated aromatic C for both soils. In contrast, the two HM fractions contained more O-alkyl C and fewer aromatics than did the other humic fractions, being closer to the original organic materials in soils. We speculate that the evolutionary route of HSs is likely to be the transformation of original organic materials into HM, followed by increased degradation, further oxidization and conversion into HA, and then into FA.
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Affiliation(s)
- Jisheng Xu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Graduate School of the Chinese Academy of Science, Beijing 100049, China
| | - Bingzi Zhao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Wenying Chu
- Department of Chemistry and Biochemistry, Old Dominion University, 4541 Hampton Boulevard, Norfolk, VA 23529, United States
| | - Jingdong Mao
- Department of Chemistry and Biochemistry, Old Dominion University, 4541 Hampton Boulevard, Norfolk, VA 23529, United States
| | - Jiabao Zhang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
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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: 25] [Impact Index Per Article: 3.6] [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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Liu X, Makita Y, Hong YL, Nishiyama Y, Miyoshi T. Chemical Reactions and Their Kinetics of atactic-Polyacrylonitrile As Revealed by Solid-State 13C NMR. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b02239] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xiaoran Liu
- Department of Polymer
Science, The University of Akron, Akron, Ohio 44325-3909, United States
| | - Yuta Makita
- Department of Polymer
Science, The University of Akron, Akron, Ohio 44325-3909, United States
| | - You-lee Hong
- RIKEN CLST-JEOL
Collaboration Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan
| | - Yusuke Nishiyama
- RIKEN CLST-JEOL
Collaboration Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan
- JEOL RESONANCE Inc., Akishima, Tokyo 196-8558, Japan
| | - Toshikazu Miyoshi
- Department of Polymer
Science, The University of Akron, Akron, Ohio 44325-3909, United States
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45
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Fu XB, Yang LY, Ma JQ, Yang G, Yao YF, Chen Q. Revealing structure and dynamics in host–guest supramolecular crystalline polymer electrolytes by solid-state NMR: Applications to β-CD-polyether/Li+ crystal. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.10.041] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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46
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Zhang D, Duan D, Huang Y, Yang Y, Ran Y. Novel Phenanthrene Sorption Mechanism by Two Pollens and Their Fractions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:7305-7314. [PMID: 27322011 DOI: 10.1021/acs.est.6b00046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A pair of pollens (Nelumbo nucifera and Brassica campestris L.) and their fractions were characterized by elemental analysis and advanced solid-state (13)C NMR techniques and used as biosorbents for phenanthrene (Phen). Their constituents were largely aliphatic components (including sporopollenin), carbohydrates, protein, and lignin as estimated by (13)C NMR spectra of the investigated samples and the four listed biochemical classes. The structure of each nonhydrolyzable carbon (NHC) fraction is similar to that of sporopollenin. The sorption capacities are highly negatively related to polar groups largely derived from carbohydrates and protein but highly positively related to alkyl carbon, poly(methylene) carbon, and aromatic carbon largely derived from sporopollenin and lignin. The sorption capacities of the NHC fractions are much higher than previously reported values, suggesting that they are good sorbents for Phen. The Freundlich n values significantly decrease with increasing concentrations of poly(methylene) carbon, alkyl C, aromatic moieties, aliphatic components, and the lignin of the pollen sorbents, suggesting that aliphatic and aromatic structures and constituents jointly contribute to the increasing nonlinearity. To our knowledge, this is the first investigation of the combined roles of alkyl and aromatic moiety domains, composition, and accessibility on the sorption of Phen by pollen samples.
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Affiliation(s)
- Dainan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
| | - Dandan Duan
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
| | - Youda Huang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
- University of Chinese Academy of Sciences , Beijing 100049, China
| | - Yu Yang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
| | - Yong Ran
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
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Fu H, Liu H, Mao J, Chu W, Li Q, Alvarez PJJ, Qu X, Zhu D. Photochemistry of Dissolved Black Carbon Released from Biochar: Reactive Oxygen Species Generation and Phototransformation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:1218-26. [PMID: 26717492 DOI: 10.1021/acs.est.5b04314] [Citation(s) in RCA: 167] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Dissolved black carbon (BC) released from biochar can be one of the more photoactive components in the dissolved organic matter (DOM) pool. Dissolved BC was mainly composed of aliphatics and aromatics substituted by aromatic C-O and carboxyl/ester/quinone moieties as determined by solid-state nuclear magnetic resonance. It underwent 56% loss of absorbance at 254 nm, almost complete loss of fluorescence, and 30% mineralization during a 169 h simulated sunlight exposure. Photoreactions preferentially targeted aromatic and methyl moieties, generating CH2/CH/C and carboxyl/ester/quinone functional groups. During irradiation, dissolved BC generated reactive oxygen species (ROS) including singlet oxygen and superoxide. The apparent quantum yield of singlet oxygen was 4.07 ± 0.19%, 2-3 fold higher than many well-studied DOM. Carbonyl-containing structures other than aromatic ketones were involved in the singlet oxygen sensitization. The generation of superoxide apparently depended on electron transfer reactions mediated by silica minerals in dissolved BC, in which phenolic structures served as electron donors. Self-generated ROS played an important role in the phototransformation. Photobleaching of dissolved BC decreased its ability to further generate ROS due to lower light absorption. These findings have significant implications on the environmental fate of dissolved BC and that of priority pollutants.
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Affiliation(s)
- Heyun Fu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing, Jiangsu 210023, China
| | - Huiting Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing, Jiangsu 210023, China
| | - Jingdong Mao
- Department of Chemistry and Biochemistry, Old Dominion University , Norfolk Virginia 23529, United States
| | - Wenying Chu
- Department of Chemistry and Biochemistry, Old Dominion University , Norfolk Virginia 23529, United States
| | - Qilin Li
- Department of Civil and Environmental Engineering, Rice University , Houston Texas 77005, United States
| | - Pedro J J Alvarez
- Department of Civil and Environmental Engineering, Rice University , Houston Texas 77005, United States
| | - Xiaolei Qu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing, Jiangsu 210023, China
| | - Dongqiang Zhu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing, Jiangsu 210023, China
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Jung C, Phal N, Oh J, Chu KH, Jang M, Yoon Y. Removal of humic and tannic acids by adsorption-coagulation combined systems with activated biochar. JOURNAL OF HAZARDOUS MATERIALS 2015; 300:808-814. [PMID: 26340547 DOI: 10.1016/j.jhazmat.2015.08.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 08/12/2015] [Accepted: 08/13/2015] [Indexed: 05/28/2023]
Abstract
Despite recent interest in transforming biomass into bio-oil and syngas, there is inadequate information on the compatibility of byproducts (e.g., biochar) with agriculture and water purification infrastructures. A pyrolysis at 300°C yields efficient production of biochar, and its physicochemical properties can be improved by chemical activation, resulting in a suitable adsorbent for the removal of natural organic matter (NOM), including hydrophobic and hydrophilic substances, such as humic acids (HA) and tannic acids (TA), respectively. In this study, the adsorption affinities of different HA and TA combinations in NOM solutions were evaluated, and higher adsorption affinity of TA onto activated biochar (AB) produced in the laboratory was observed due to its superior chemisorption tendencies and size-exclusion effects compared with that of HA, whereas hydrophobic interactions between adsorbent and adsorbate were deficient. Assessment of the AB role in an adsorption-coagulation hybrid system as nuclei for coagulation in the presence of aluminum sulfate (alum) showed a synergistic effect in a HA-dominated NOM solution. An AB-alum hybrid system with a high proportion of HA in the NOM solution may be applicable as an end-of-pipe solution.
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Affiliation(s)
- Chanil Jung
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA; Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA
| | - Narong Phal
- Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA
| | - Jeill Oh
- Department of Civil and Environmental Engineering, Chung-Ang University, 84Heukseok-ro, Dongjak-gu, Seoul 156756, South Korea
| | - Kyoung Hoon Chu
- Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA
| | - Min Jang
- Department of Civil Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Yeomin Yoon
- Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA.
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Qian S, Ding W, Li Y, Liu G, Sun J, Ding Q. Characterization of humic acids derived from Leonardite using a solid-state NMR spectroscopy and effects of humic acids on growth and nutrient uptake of snap bean. CHEMICAL SPECIATION & BIOAVAILABILITY 2015. [DOI: 10.1080/09542299.2015.1118361] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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50
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Johnson RL, Schwartz TJ, Dumesic JA, Schmidt-Rohr K. Methionine bound to Pd/γ-Al2O3 catalysts studied by solid-state (13)C NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 72:64-72. [PMID: 26422257 DOI: 10.1016/j.ssnmr.2015.09.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 09/07/2015] [Accepted: 09/11/2015] [Indexed: 06/05/2023]
Abstract
The chemisorption and breakdown of methionine (Met) adsorbed on Pd/γ-Al2O3 catalysts were investigated by solid-state NMR. (13)C-enriched Met (ca. 0.4mg) impregnated onto γ-Al2O3 or Pd/γ-Al2O3 gives NMR spectra with characteristic features of binding to γ-Al2O3, to Pd nanoparticles, and oxidative or reductive breakdown of Met. The SCH3 groups of Met showed characteristic changes in chemical shift on γ-Al2O3 (13ppm) vs. Pd (19ppm), providing strong evidence for preferential binding to Pd, while the NC carbon generates a small resonance at 96ppm assigned to a distinct nonprotonated species bound to O or Pd. Additionally, NMR shows that the SCH3 groups of Met are mobile on γ-Al2O3 but immobilized by binding to Pd particles; on small Pd particles (ca. 4nm), the NCH groups undergo large-amplitude motions. In a reducing environment, Met breaks down by C-S bond cleavage followed by formation of C2-C4 organic acids. The SCH3 signal shifts to 22ppm, which is likely the signature of the principal species responsible for strong catalyst inhibition. These experiments demonstrate that solid-state magic-angle spinning NMR of (13)C-enriched Met can be a sensitive probe to investigate catalyst surfaces and characterize catalyst inhibition both before reaction and postmortem.
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Affiliation(s)
- Robert L Johnson
- Department of Chemistry, Iowa State University, Ames, IA 50011, United States
| | - Thomas J Schwartz
- Department of Chemical and Biological Engineering, University of Wisconsin, Madison, WI 53706, United States
| | - James A Dumesic
- Department of Chemical and Biological Engineering, University of Wisconsin, Madison, WI 53706, United States
| | - Klaus Schmidt-Rohr
- Department of Chemistry, Iowa State University, Ames, IA 50011, United States; Department of Chemistry, Brandeis University, Waltham, MA 02453, United States.
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