1
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Frank N, Nugent J, Shire BR, Pickford HD, Rabe P, Sterling AJ, Zarganes-Tzitzikas T, Grimes T, Thompson AL, Smith RC, Schofield CJ, Brennan PE, Duarte F, Anderson EA. Synthesis of meta-substituted arene bioisosteres from [3.1.1]propellane. Nature 2022; 611:721-726. [PMID: 36108675 DOI: 10.1038/s41586-022-05290-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/30/2022] [Indexed: 11/08/2022]
Abstract
Small-ring cage hydrocarbons are popular bioisosteres (molecular replacements) for commonly found para-substituted benzene rings in drug design1. The utility of these cage structures derives from their superior pharmacokinetic properties compared with their parent aromatics, including improved solubility and reduced susceptibility to metabolism2,3. A prime example is the bicyclo[1.1.1]pentane motif, which is mainly synthesized by ring-opening of the interbridgehead bond of the strained hydrocarbon [1.1.1]propellane with radicals or anions4. By contrast, scaffolds mimicking meta-substituted arenes are lacking because of the challenge of synthesizing saturated isosteres that accurately reproduce substituent vectors5. Here we show that bicyclo[3.1.1]heptanes (BCHeps), which are hydrocarbons for which the bridgehead substituents map precisely onto the geometry of meta-substituted benzenes, can be conveniently accessed from [3.1.1]propellane. We found that [3.1.1]propellane can be synthesized on a multigram scale, and readily undergoes a range of radical-based transformations to generate medicinally relevant carbon- and heteroatom-substituted BCHeps, including pharmaceutical analogues. Comparison of the absorption, distribution, metabolism and excretion (ADME) properties of these analogues reveals enhanced metabolic stability relative to their parent arene-containing drugs, validating the potential of this meta-arene analogue as an sp3-rich motif in drug design. Collectively, our results show that BCHeps can be prepared on useful scales using a variety of methods, offering a new surrogate for meta-substituted benzene rings for implementation in drug discovery programmes.
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Affiliation(s)
- Nils Frank
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Jeremy Nugent
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Bethany R Shire
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Helena D Pickford
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Patrick Rabe
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Alistair J Sterling
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Tryfon Zarganes-Tzitzikas
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine, Oxford, UK
| | - Thomas Grimes
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine, Oxford, UK
| | - Amber L Thompson
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Russell C Smith
- Abbvie Drug Discovery Science & Technology (DDST), North Chicago, IL, USA
| | | | - Paul E Brennan
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine, Oxford, UK
| | - Fernanda Duarte
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Edward A Anderson
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK.
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2
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Zhao JX, Chang YX, He C, Burke BJ, Collins MR, Del Bel M, Elleraas J, Gallego GM, Montgomery TP, Mousseau JJ, Nair SK, Perry MA, Spangler JE, Vantourout JC, Baran PS. 1,2-Difunctionalized bicyclo[1.1.1]pentanes: Long-sought-after mimetics for ortho/ meta-substituted arenes. Proc Natl Acad Sci U S A 2021; 118:e2108881118. [PMID: 34244445 PMCID: PMC8285974 DOI: 10.1073/pnas.2108881118] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The development of a versatile platform for the synthesis of 1,2-difunctionalized bicyclo[1.1.1]pentanes to potentially mimic ortho/meta-substituted arenes is described. The syntheses of useful building blocks bearing alcohol, amine, and carboxylic acid functional handles have been achieved from a simple common intermediate. Several ortho- and meta-substituted benzene analogs, as well as simple molecular matched pairs, have also been prepared using this platform. The results of in-depth ADME (absorption, distribution, metabolism, and excretion) investigations of these systems are presented, as well as computational studies which validate the ortho- or meta-character of these bioisosteres.
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Affiliation(s)
- Jin-Xin Zhao
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China
| | - Yu-Xuan Chang
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
| | - Chi He
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
| | - Benjamin J Burke
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | - Michael R Collins
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121;
| | - Matthew Del Bel
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | - Jeff Elleraas
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | - Gary M Gallego
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | - T Patrick Montgomery
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | - James J Mousseau
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research, Development and Medical, Groton, CT 06340
| | - Sajiv K Nair
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | - Matthew A Perry
- Discovery Sciences, Medicine Design, Pfizer Worldwide Research, Development and Medical, Groton, CT 06340
| | - Jillian E Spangler
- Oncology Medicinal Chemistry, Pfizer Worldwide Research, Development and Medical, San Diego, CA 92121
| | | | - Phil S Baran
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037;
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3
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Abstract
In the development of dermal drug formulations and cosmetics, understanding the penetration properties of the active ingredients is crucial. Given that widespread methods, including tape stripping, lack in spatial resolution, while being time- and labour-intensive, Confocal Raman Microscopy is a promising alternative. In optimizing topically applied formulations, or the development of generic formulations, comparative in-situ measurements have a huge potential of saving time and resources. In this work, we show our approach to in-situ skin penetration analysis by confocal Raman Microscopy. To analyse feasibility of the approach, we used caffeine solutions as model vehicles and tested the effectiveness of 1,2-pentanediol as a penetration enhancer for delivery to the skin.
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Affiliation(s)
| | - Dominique Lunter
- Department of Pharmaceutical Technology, Eberhard Karls University, Auf der Morgenstelle 8, 72076 Tuebingen, Germany;
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4
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Sun J, Shen Z, Zhang Y, Zhang Z, Zhang Q, Zhang T, Niu X, Huang Y, Cui L, Xu H, Liu H, Cao J, Li X. Urban VOC profiles, possible sources, and its role in ozone formation for a summer campaign over Xi'an, China. Environ Sci Pollut Res Int 2019; 26:27769-27782. [PMID: 31338768 DOI: 10.1007/s11356-019-05950-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
To insight the urban volatile organic compound (VOC) profiles and its contribution to ozone, four-time per day (8:00-9:00, 15:00-16:00, 19:00-20:00, and 23:00-24:00) off-line VOC samples were collected from 16th July to 28th July 2018 for a summer investigation campaign over Xi'an, China. The diurnal variation was significant that the lowest TVOC concentrations were observed in the midnight period (28.4 ± 25.6 ppbv) while the highest was shown in the morning (49.6 ± 40.1 ppbv). The differences of total non-methane VOCs (TVOCs) between weekdays and weekend were also significant that the weekend showed significantly high VOC levels than weekdays (p < 0.05) but did not lead to significant ambient O3 increase (p > 0.05). Isopentane, a general marker for vehicle exhaust, showed descending concentrations from morning to midnight and good correlation with vehicle numbers on road, indicating a potential source to the VOCs at this site. The results from PMF proved that vehicular exhaust was the largest source to the VOCs in this study (64.4%). VOC categories showed a reverse sequence in abundance of concentrations and OFP contributions that alkenes showed the highest OFPs although with the lowest abundance in TOVCs due to their high reactivity in photochemical reactions. High OFPs from ethylene and isopentane indicated that vehicular emissions could be the largest potential OFP source in this site. OFPs from isoprene (from 1.85 to 13.4 ppbv) indicated that biogenic VOCs should not be negligible in urban Xi'an city when controlling O3 pollutants. Comparison of two OFP methods was conducted and MIR method was proved to be more reasonable and scientific in summer Xi'an. Therefore, vehicular emission, the largest contributor to ambient VOCs and also OFPs, as well as biological source should be priority controlled in guiding VOC emissions and reducing O3 control policies.
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Affiliation(s)
- Jian Sun
- School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Zhenxing Shen
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China.
| | - Yue Zhang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Zhou Zhang
- Changsha Center for Mineral Resources Exploration, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Changsha, China
| | - Qian Zhang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Tian Zhang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Xinyi Niu
- The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China
| | - Yu Huang
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710049, China
| | - Long Cui
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710049, China
| | - Hongmei Xu
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Hongxia Liu
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Junji Cao
- Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710049, China
| | - Xuxiang Li
- School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
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5
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Arashiro M, Lin YH, Zhang Z, Sexton KG, Gold A, Jaspers I, Fry RC, Surratt JD. Effect of secondary organic aerosol from isoprene-derived hydroxyhydroperoxides on the expression of oxidative stress response genes in human bronchial epithelial cells. Environ Sci Process Impacts 2018; 20:332-339. [PMID: 29292423 DOI: 10.1039/c7em00439g] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Isoprene-derived secondary organic aerosol (SOA), which comprise a large portion of atmospheric fine particulate matter (PM2.5), can be formed through various gaseous precursors, including isoprene epoxydiols (IEPOX), methacrylic acid epoxide (MAE), and isoprene hydroxyhydroperoxides (ISOPOOH). The composition of the isoprene-derived SOA affects its reactive oxygen species (ROS) generation potential and its ability to alter oxidative stress-related gene expression. In this study we assess effects of isoprene SOA derived solely from ISOPOOH oxidation on human bronchial epithelial cells by measuring the gene expression changes in 84 oxidative stress-related genes. In addition, the thiol reactivity of ISOPOOH-derived SOA was measured through the dithiothreitol (DTT) assay. Our findings show that ISOPOOH-derived SOA alter more oxidative-stress related genes than IEPOX-derived SOA but not as many as MAE-derived SOA on a mass basis exposure. More importantly, we found that the different types of SOA derived from the various gaseous precursors (MAE, IEPOX, and ISOPOOH) have unique contributions to changes in oxidative stress-related genes that do not total all gene expression changes seen in exposures to atmospherically relevant compositions of total isoprene-derived SOA mixtures. This study suggests that amongst the different types of known isoprene-derived SOA, MAE-derived SOA are the most potent inducer of oxidative stress-related gene changes but highlights the importance of considering isoprene-derived SOA as a total mixture for pollution controls and exposure studies.
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Affiliation(s)
- Maiko Arashiro
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
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6
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Califano V, Bloisi F, Perretta G, Aronne A, Ausanio G, Costantini A, Vicari L. Frozen Microemulsions for MAPLE Immobilization of Lipase. Molecules 2017; 22:molecules22122153. [PMID: 29206163 PMCID: PMC6149894 DOI: 10.3390/molecules22122153] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/26/2017] [Accepted: 11/27/2017] [Indexed: 11/16/2022] Open
Abstract
Candida rugosa lipase (CRL) was deposited by matrix assisted pulsed laser evaporation (MAPLE) in order to immobilize the enzyme with a preserved native conformation, which ensures its catalytic functionality. For this purpose, the composition of the MAPLE target was optimized by adding the oil phase pentane to a water solution of the amino acid 3-(3,4-dihydroxyphenyl)-2-methyl-l-alanine (m-DOPA), giving a target formed by a frozen water-lipase-pentane microemulsion. Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) were used to investigate the structure of MAPLE deposited lipase films. FTIR deconvolution of amide I band indicated a reduction of unfolding and aggregation, i.e., a better preserved lipase secondary structure in the sample deposited from the frozen microemulsion target. AFM images highlighted the absence of big aggregates on the surface of the sample. The functionality of the immobilized enzyme to promote transesterification was determined by thin layer chromatography, resulting in a modified specificity.
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Affiliation(s)
| | - Francesco Bloisi
- CNR-SPIN and Department of Physics "Ettore Pancini", University of Naples Federico II, Piazzale V. Tecchio 80, 80125 Napoli, Italy.
| | | | - Antonio Aronne
- Department of Chemical Engineering, Materials and Industrial Production, University of Naples Federico II, Piazzale V. Tecchio 80, 80125 Napoli, Italy.
| | - Giovanni Ausanio
- CNR-SPIN and Department of Physics "Ettore Pancini", University of Naples Federico II, Piazzale V. Tecchio 80, 80125 Napoli, Italy.
| | - Aniello Costantini
- Department of Chemical Engineering, Materials and Industrial Production, University of Naples Federico II, Piazzale V. Tecchio 80, 80125 Napoli, Italy.
| | - Luciano Vicari
- CNR-SPIN and Department of Physics "Ettore Pancini", University of Naples Federico II, Piazzale V. Tecchio 80, 80125 Napoli, Italy.
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7
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Abstract
Isoprene units derived from dimethylallyl diphosphate (DMAPP) are an important motif in many natural products including terpenoids, carotenoids, steroids, and natural rubber. Understanding the chemical characteristics of DMAPP is an important topic in natural products chemistry, organic chemistry, and biochemistry. We have developed a direct bioinspired indole prenylation reaction using DMAPP or its equivalents as the electrophile in homogeneous aqueous acidic media in the absence of enzyme to provide prenylated indole products. After establishing the bioinspired indole prenylation reaction, this was then used to achieve the synthesis of a series of natural products, namely, N-prenylcyclo-l-tryptophyl-l-proline, tryprostatins, rhinocladins, and terezine D.
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Affiliation(s)
- Satomi Tanaka
- Department of Chemistry, Graduate School of Science and Technology, Kumamoto University , 2-39-1, Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Shinya Shiomi
- Department of Chemistry, Graduate School of Science and Technology, Kumamoto University , 2-39-1, Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Hayato Ishikawa
- Department of Chemistry, Graduate School of Science and Technology, Kumamoto University , 2-39-1, Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
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8
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Ricci G, Boccia AC, Leone G, Pierro I, Zanchin G, Scoti M, Auriemma F, De Rosa C. Isotactic and Syndiotactic Alternating Ethylene/Propylene Copolymers Obtained Through Non-Catalytic Hydrogenation of Highly Stereoregular cis-1,4 Poly(1,3-diene)s. Molecules 2017; 22:molecules22050755. [PMID: 28481242 PMCID: PMC6154095 DOI: 10.3390/molecules22050755] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/02/2017] [Accepted: 05/03/2017] [Indexed: 12/02/2022] Open
Abstract
The homogeneous non-catalytic hydrogenation of cis-1,4 poly(isoprene), isotactic cis-1,4 poly(1,3-pentadiene) and syndiotactic cis-1,4 poly(1,3-pentadiene) with diimide, formed by thermal decomposition of para-toluenesulfonylhydrazide, is examined. Perfectly alternating ethylene/propylene copolymers having different tacticity (i.e., isotactic and syndiotactic), which are difficult to synthesize by stereospecific copolymerization of the corresponding monomers, are obtained. Both isotactic and syndiotactic alternating ethylene/propylene copolymers are amorphous, with very low glass transition temperatures.
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Affiliation(s)
- Giovanni Ricci
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), Via A. Corti 12, I-20133 Milano, Italy.
| | | | - Giuseppe Leone
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), Via A. Corti 12, I-20133 Milano, Italy.
| | - Ivana Pierro
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), Via A. Corti 12, I-20133 Milano, Italy.
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy.
| | - Giorgia Zanchin
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), Via A. Corti 12, I-20133 Milano, Italy.
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, I-20133 Milano, Italy.
| | - Miriam Scoti
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy.
| | - Finizia Auriemma
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy.
| | - Claudio De Rosa
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy.
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9
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Brentzel ZJ, Barnett KJ, Huang K, Maravelias CT, Dumesic JA, Huber GW. Chemicals from Biomass: Combining Ring-Opening Tautomerization and Hydrogenation Reactions to Produce 1,5-Pentanediol from Furfural. ChemSusChem 2017; 10:1351-1355. [PMID: 28277620 DOI: 10.1002/cssc.201700178] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 02/08/2017] [Indexed: 05/16/2023]
Abstract
A process for the synthesis of 1,5-pentanediol (1,5-PD) with 84 % yield from furfural is developed, utilizing dehydration/hydration, ring-opening tautomerization, and hydrogenation reactions. Although this process has more reaction steps than the traditional direct hydrogenolysis of tetrahydrofurfuryl alcohol (THFA), techno-economic analyses demonstrate that this process is the economically preferred route for the synthesis of biorenewable 1,5-PD. 2-Hydroxytetrahydropyran (2-HY-THP) is the key reaction pathway intermediate that allows for a decrease in the minimum selling price of 1,5-PD. The reactivity of 2-HY-THP is 80 times greater than that of THFA over a bimetallic hydrogenolysis catalyst. This enhanced reactivity is a result of the ring-opening tautomerization to 5-hydoxyvaleraldehyde and subsequent hydrogenation to 1,5-PD.
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Affiliation(s)
- Zachary J Brentzel
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Kevin J Barnett
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Kefeng Huang
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Christos T Maravelias
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - James A Dumesic
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - George W Huber
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
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10
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Dai T, Li C, Zhang B, Guo H, Pan X, Li L, Wang A, Zhang T. Selective Production of Toluene from Biomass-Derived Isoprene and Acrolein. ChemSusChem 2016; 9:3434-3440. [PMID: 27885809 DOI: 10.1002/cssc.201601267] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 10/17/2016] [Indexed: 06/06/2023]
Abstract
Toluene is a basic chemical that is currently produced from petroleum resources. In this paper, we report a new route for the effective synthesis of toluene from isoprene and acrolein, two reactants readily available from biomass, through a simple two-step reaction. The process includes Diels-Alder cycloaddition of isoprene and acrolein in a Zn-containing ionic liquid at room temperature to produce methylcyclohex-3-enecarbaldehydes (MCHCAs) as intermediates, followed by M (M=Pt, Pd, Rh)/Al2 O3 -catalyzed consecutive dehydrogenation-decarbonylation of the MCHCAs at 573 K to generate toluene with an overall yield up to 90.7 %. Model reactions indicated that a synergistic inductive effect of the C=C double bond and the aldehyde group in MCHCA plays a key role in initiating the consecutive dehydrogenation-decarbonylation, and that methyl benzaldehydes are the key intermediates in the gas-phase transformation of MCHCAs. Microcalorimetric adsorption of CO on different catalysts showed that decarbonylation of the substrate occurs more likely on the strong adsorption sites. To the best of our knowledge, it is the first report of Pt/Al2 O3 -catalyzed consecutive dehydrogenation-decarbonylation of a given compound in one reactor. This work provides a highly efficient and environmental friendly route to toluene by utilizing two compounds that can be prepared from biomass.
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Affiliation(s)
- Tao Dai
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Changzhi Li
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
| | - Bo Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
| | - Haiwei Guo
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Xiaoli Pan
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
| | - Lin Li
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
| | - Aiqin Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
| | - Tao Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P.R. China
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11
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da Silva CM, da Silva LL, Corrêa SM, Arbilla G. Kinetic and mechanistic reactivity. Isoprene impact on ozone levels in an urban area near Tijuca Forest, Rio de Janeiro. Bull Environ Contam Toxicol 2016; 97:781-785. [PMID: 27738711 DOI: 10.1007/s00128-016-1949-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 10/07/2016] [Indexed: 06/06/2023]
Abstract
Volatile organic compounds (VOCs) play a central role in atmospheric chemistry. In this work, the kinetic and mechanistic reactivities of VOCs are analyzed, and the contribution of the organic compounds emitted by anthropogenic and natural sources is estimated. VOCs react with hydroxyl radicals and other photochemical oxidants, such as ozone and nitrate radicals, which cause the conversion of NO to NO2 in various potential reaction paths, including photolysis, to form oxygen atoms, which generate ozone. The kinetic reactivity was evaluated based on the reaction coefficients for hydroxyl radicals with VOCs. The mechanistic reactivity was estimated using a detailed mechanism and the incremental reactivity scale that Carter proposed. Different scenarios were proposed and discussed, and a minimum set of compounds, which may describe the tropospheric reactivity in the studied area, was determined. The role of isoprene was analyzed in terms of its contribution to ozone formation.
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Affiliation(s)
- Cleyton Martins da Silva
- Centro de Tecnologia, Instituto de Química, Universidade Federal do Rio de Janeiro, Bloco A, Sala 402A, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21949-900, Brazil
- Faculdade de Tecnologia, Universidade do Estado do Rio de Janeiro, Rodovia Presidente Dutra, km 298, Resende, RJ, 27537-000, Brazil
| | - Luane Lima da Silva
- Centro de Tecnologia, Instituto de Química, Universidade Federal do Rio de Janeiro, Bloco A, Sala 402A, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21949-900, Brazil
| | - Sergio Machado Corrêa
- Faculdade de Tecnologia, Universidade do Estado do Rio de Janeiro, Rodovia Presidente Dutra, km 298, Resende, RJ, 27537-000, Brazil
| | - Graciela Arbilla
- Centro de Tecnologia, Instituto de Química, Universidade Federal do Rio de Janeiro, Bloco A, Sala 402A, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21949-900, Brazil.
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12
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Cash JM, Heal MR, Langford B, Drewer J. A review of stereochemical implications in the generation of secondary organic aerosol from isoprene oxidation. Environ Sci Process Impacts 2016; 18:1369-1380. [PMID: 27762408 DOI: 10.1039/c6em00354k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The atmospheric reactions leading to the generation of secondary organic aerosol (SOA) from the oxidation of isoprene are generally assumed to produce only racemic mixtures, but aspects of the chemical reactions suggest this may not be the case. In this review, the stereochemical outcomes of published isoprene-degradation mechanisms contributing to high amounts of SOA are evaluated. Despite evidence suggesting isoprene first-generation oxidation products do not contribute to SOA directly, this review suggests the stereochemistry of first-generation products may be important because their stereochemical configurations may be retained through to the second-generation products which form SOA. Specifically, due to the stereochemistry of epoxide ring-opening mechanisms, the outcome of the reactions involving epoxydiols of isoprene (IEPOX), methacrylic acid epoxide (MAE) and hydroxymethylmethyl-α-lactone (HMML) are, in principle, stereospecific which indicates the stereochemistry is predefined from first-generation precursors. The products from these three epoxide intermediates oligomerise to form macromolecules which are proposed to form chiral structures within the aerosol and are considered to be the largest contributors to SOA. If conditions in the atmosphere such as pH, aerosol water content, relative humidity, pre-existing aerosol, aerosol coatings and aerosol cation/anion content (and other) variables acting on the reactions leading to SOA affect the tacticity (arrangement of chiral centres) in the SOA then they may influence its physical properties, for example its hygroscopicity. Chamber studies of SOA formation from isoprene encompass particular sets of controlled conditions of these variables. It may therefore be important to consider stereochemistry when upscaling from chamber study data to predictions of SOA yields across the range of ambient atmospheric conditions. Experiments analysing the stereochemistry of the reactions under varying conditions of the above variables would help elucidate whether there is stereoselectivity in SOA formation from isoprene and if the rates of SOA formation are affected.
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Affiliation(s)
- James M Cash
- NERC Centre for Ecology and Hydrology, Bush Estate, Penicuik, EH26 0QB, UK. and School of Chemistry, The University of Edinburgh, David Brewster Rd, Edinburgh EH9 3FJ, UK
| | - Mathew R Heal
- School of Chemistry, The University of Edinburgh, David Brewster Rd, Edinburgh EH9 3FJ, UK
| | - Ben Langford
- NERC Centre for Ecology and Hydrology, Bush Estate, Penicuik, EH26 0QB, UK.
| | - Julia Drewer
- NERC Centre for Ecology and Hydrology, Bush Estate, Penicuik, EH26 0QB, UK.
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13
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Shi LL, Ma GX, Gao HC, Chen QC, Yang JS, Jia XG, Zhang J. Diarylpentanol constituents from the aerial part of Stelleropsis tianschanica. J Asian Nat Prod Res 2016; 18:885-890. [PMID: 27170544 DOI: 10.1080/10286020.2016.1171759] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 03/22/2016] [Indexed: 06/05/2023]
Abstract
Five diarylpentanol derivatives including two new compounds stellerasme A (1), stellerasme B (2) were isolated from the aerial parts of Stelleropsis tianschanica. Their structures were elucidated by various spectroscopic techniques (UV, IR, MS, CD, 1D and 2D NMR). All compounds were evaluated for their cytotoxicity activity against HeLa and KB cell lines, and compound 1 showed selective activities against HeLa cell line with an IC50 value of 7.4 μM.
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Affiliation(s)
- Lei-Ling Shi
- a Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education , Institute of Medicinal Plant Development , Beijing 100193 , China
- b Department of Natural Medicinal Chemistry , Xinjiang Institute of Chinese and Ethnic Medicine , Urumqi 830002 , China
| | - Guo-Xu Ma
- a Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education , Institute of Medicinal Plant Development , Beijing 100193 , China
- b Department of Natural Medicinal Chemistry , Xinjiang Institute of Chinese and Ethnic Medicine , Urumqi 830002 , China
| | - Hua-Chun Gao
- d School of Pharmaceutical Sciences , Xiamen University , Xiamen 361102 , China
| | - Quan-Cheng Chen
- d School of Pharmaceutical Sciences , Xiamen University , Xiamen 361102 , China
| | - Jun-Shan Yang
- a Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education , Institute of Medicinal Plant Development , Beijing 100193 , China
| | - Xiao-Guang Jia
- b Department of Natural Medicinal Chemistry , Xinjiang Institute of Chinese and Ethnic Medicine , Urumqi 830002 , China
| | - Jing Zhang
- c College of Chinese Medicinal Material , Jilin Agricultural University , Changchun 130118 , China
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14
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Millet DB, Baasandorj M, Hu L, Mitroo D, Turner J, Williams BJ. Nighttime Chemistry and Morning Isoprene Can Drive Urban Ozone Downwind of a Major Deciduous Forest. Environ Sci Technol 2016; 50:4335-4342. [PMID: 27010702 DOI: 10.1021/acs.est.5b06367] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Isoprene is the predominant non-methane volatile organic compound emitted to the atmosphere and shapes tropospheric composition and biogeochemistry through its effects on ozone, other oxidants, aerosols, and the nitrogen cycle. Isoprene is emitted naturally by vegetation during daytime, when its photo-oxidation is rapid, and in the presence of nitrogen oxides (NOx) produces ozone and degrades air quality in polluted regions. Here, we show for a city downwind of an isoprene-emitting forest (St. Louis, MO) that isoprene actually peaks at night; ambient levels then endure, owing to low nighttime OH radical concentrations. Nocturnal chemistry controls the fate of that isoprene and the likelihood of a high-ozone episode the following day. When nitrate (NO3) radicals are suppressed, high isoprene persists through the night, providing photochemical fuel upon daybreak and leading to a dramatic late-morning ozone peak. On nights with significant NO3, isoprene is removed before dawn; days with low morning isoprene then have lower ozone with a more typical afternoon peak. This biogenic-anthropogenic coupling expands the daily high-ozone window and likely has an opposite O3-NOx response to what would otherwise be expected, with implications for exposure and air-quality management in cities that, like St. Louis, are downwind of major isoprene-emitting forests.
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Affiliation(s)
- Dylan B Millet
- University of Minnesota , St. Paul, Minnesota 55108, United States
| | | | - Lu Hu
- University of Minnesota , St. Paul, Minnesota 55108, United States
| | - Dhruv Mitroo
- Washington University in St. Louis , St. Louis, Missouri 63130, United States
| | - Jay Turner
- Washington University in St. Louis , St. Louis, Missouri 63130, United States
| | - Brent J Williams
- Washington University in St. Louis , St. Louis, Missouri 63130, United States
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15
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Pawlicki A, Avery E, Jurow M, Ewers B, Vilan A, Drain CM, Batteas J. Studies of the structure and phase transitions of nano-confined pentanedithiol and its application in directing hierarchical molecular assemblies on Au(1 1 1). J Phys Condens Matter 2016; 28:094013. [PMID: 26872125 DOI: 10.1088/0953-8984/28/9/094013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Directing molecular devices into pre-designed integrated electronic circuits while enforcing selectivity and hierarchy is an inherent challenge for molecular electronics. Here we explore ways to direct the assembly of electrically-active molecular monolayers into specific locations as well as controlling their internal organization. We have accomplished this by two consecutive surface reactions: (1) forming pentanedithiol (C5DT) domains within an inert alkanethiol self-assembled monolayer (SAM) on Au; and (2) selectively binding porphyrin derivatives to the C5DT domains. The C5DT domains were fabricated by phase segregation during co-adsorption from a mixed C5DT/dodecanethiol (C12) solution and nanografting with Atomic Force Microscopy (AFM). AFM revealed that co-absorbed and nanografted C5DT domains were in a standing-up phase and scanning tunneling microscopy (STM) showed that their molecular organization within about 5 nm, 40 nm, 50 nm and 120 nm domains, was dependent upon the size of the domain, such that structure of the C5DT transitions from (√3 × √3) R30°, to (2 × 2), and ultimately to a disordered phase with increasing domain size. This is due to the varying degrees of influence of the surrounding C12; providing sufficient van der Waals interactions as well as a geometric confinement to stabilize the standing-up phase of the C5DT. Understanding the molecular configuration of dithiol SAMs affords their use as a reactive template to subsequently bind active head groups. As a proof of principle, porphyrins with a pendant pentafluorophenyl ring were attached to the C5DT domains by a 'click' reaction between the fluorinated ring and the free thiol on the surface. From AFM and STM, these porphyrin derivatives reacted selectively with the C5DT domains with some porphyrins binding directly to the C5DT, subsequently allowing additional localized porphyrin deposition through pi-stacking.
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Affiliation(s)
- Alison Pawlicki
- Departments of Chemistry and Materials Science and Engineering, Texas A&M University, College Station, TX 77843, USA
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16
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Lopez-Hilfiker FD, Mohr C, D'Ambro EL, Lutz A, Riedel TP, Gaston CJ, Iyer S, Zhang Z, Gold A, Surratt JD, Lee BH, Kurten T, Hu WW, Jimenez J, Hallquist M, Thornton JA. Molecular Composition and Volatility of Organic Aerosol in the Southeastern U.S.: Implications for IEPOX Derived SOA. Environ Sci Technol 2016; 50:2200-9. [PMID: 26811969 DOI: 10.1021/acs.est.5b04769] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present measurements as part of the Southern Oxidant and Aerosol Study (SOAS) during which atmospheric aerosol particles were comprehensively characterized. We present results utilizing a Filter Inlet for Gases and AEROsol coupled to a chemical ionization mass spectrometer (CIMS). We focus on the volatility and composition of isoprene derived organic aerosol tracers and of the bulk organic aerosol. By utilizing the online volatility and molecular composition information provided by the FIGAERO-CIMS, we show that the vast majority of commonly reported molecular tracers of isoprene epoxydiol (IEPOX) derived secondary organic aerosol (SOA) is derived from thermal decomposition of accretion products or other low volatility organics having effective saturation vapor concentrations <10(-3) μg m(-3). In addition, while accounting for up to 30% of total submicrometer organic aerosol mass, the IEPOX-derived SOA has a higher volatility than the remaining bulk. That IEPOX-SOA, and more generally bulk organic aerosol in the Southeastern U.S. is comprised of effectively nonvolatile material has important implications for modeling SOA derived from isoprene, and for mechanistic interpretations of molecular tracer measurements. Our results show that partitioning theory performs well for 2-methyltetrols, once accretion product decomposition is taken into account. No significant partitioning delays due to aerosol phase or viscosity are observed, and no partitioning to particle-phase water or other unexplained mechanisms are needed to explain our results.
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Affiliation(s)
- F D Lopez-Hilfiker
- Department of Atmospheric Sciences, University of Washington , Seattle, Washington 98195, United States
| | - C Mohr
- Department of Atmospheric Sciences, University of Washington , Seattle, Washington 98195, United States
| | - E L D'Ambro
- Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
| | - A Lutz
- Department of Chemistry and Molecular Biology, University of Gothenburg , 41296 Gothenburg, Sweden
| | - T P Riedel
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27516, United States
| | - C J Gaston
- Department of Atmospheric Sciences, University of Washington , Seattle, Washington 98195, United States
| | - S Iyer
- Department of Chemistry, University of Helsinki , Helsinki, Finland
| | - Z Zhang
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27516, United States
| | - A Gold
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27516, United States
| | - J D Surratt
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27516, United States
| | - B H Lee
- Department of Atmospheric Sciences, University of Washington , Seattle, Washington 98195, United States
| | - T Kurten
- Department of Chemistry, University of Helsinki , Helsinki, Finland
| | - W W Hu
- Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado 80309, United States
| | - J Jimenez
- Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado 80309, United States
| | - M Hallquist
- Department of Chemistry and Molecular Biology, University of Gothenburg , 41296 Gothenburg, Sweden
| | - J A Thornton
- Department of Atmospheric Sciences, University of Washington , Seattle, Washington 98195, United States
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17
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Pye HOT, Luecken DJ, Xu L, Boyd CM, Ng NL, Baker KR, Ayres BR, Bash JO, Baumann K, Carter WPL, Edgerton E, Fry JL, Hutzell WT, Schwede DB, Shepson PB. Modeling the Current and Future Roles of Particulate Organic Nitrates in the Southeastern United States. Environ Sci Technol 2015; 49:14195-203. [PMID: 26544021 DOI: 10.1021/acs.est.5b03738] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Organic nitrates are an important aerosol constituent in locations where biogenic hydrocarbon emissions mix with anthropogenic NOx sources. While regional and global chemical transport models may include a representation of organic aerosol from monoterpene reactions with nitrate radicals (the primary source of particle-phase organic nitrates in the Southeast United States), secondary organic aerosol (SOA) models can underestimate yields. Furthermore, SOA parametrizations do not explicitly take into account organic nitrate compounds produced in the gas phase. In this work, we developed a coupled gas and aerosol system to describe the formation and subsequent aerosol-phase partitioning of organic nitrates from isoprene and monoterpenes with a focus on the Southeast United States. The concentrations of organic aerosol and gas-phase organic nitrates were improved when particulate organic nitrates were assumed to undergo rapid (τ = 3 h) pseudohydrolysis resulting in nitric acid and nonvolatile secondary organic aerosol. In addition, up to 60% of less oxidized-oxygenated organic aerosol (LO-OOA) could be accounted for via organic nitrate mediated chemistry during the Southern Oxidants and Aerosol Study (SOAS). A 25% reduction in nitrogen oxide (NO + NO2) emissions was predicted to cause a 9% reduction in organic aerosol for June 2013 SOAS conditions at Centreville, Alabama.
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Affiliation(s)
- Havala O T Pye
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Deborah J Luecken
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Lu Xu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
| | - Christopher M Boyd
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
| | - Nga L Ng
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
| | - Kirk R Baker
- Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Benjamin R Ayres
- Department of Chemistry, Reed College , Portland, Oregon 97202, United States
| | - Jesse O Bash
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Karsten Baumann
- Atmospheric Research and Analysis, Inc., Cary, North Carolina 27513, United States
| | - William P L Carter
- College of Engineering, Center for Environmental Research and Technology, University of California at Riverside , Riverside, California 92512, United States
| | - Eric Edgerton
- Atmospheric Research and Analysis, Inc., Cary, North Carolina 27513, United States
| | - Juliane L Fry
- Department of Chemistry, Reed College , Portland, Oregon 97202, United States
| | - William T Hutzell
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Donna B Schwede
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Paul B Shepson
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
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18
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Li YJ, Liu P, Gong Z, Wang Y, Bateman AP, Bergoend C, Bertram AK, Martin ST. Chemical Reactivity and Liquid/Nonliquid States of Secondary Organic Material. Environ Sci Technol 2015; 49:13264-74. [PMID: 26465059 DOI: 10.1021/acs.est.5b03392] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The reactivity of secondary organic material (SOM) of variable viscosity, ranging from nonliquid to liquid physical states, was studied. The SOM, produced in aerosol form from terpenoid and aromatic precursor species, was reacted with ammonia at variable relative humidity (RH). The ammonium-to-organic mass ratio (MNH4+/MOrg) increased monotonically from <5% RH to a limiting value at a threshold RH, implicating a transition from particle reactivity limited by diffusion at low RH to one limited by other factors at higher RH. For the studied size distributions and reaction times, the transition corresponded to a diffusivity above 10-17.5 ± 0.5 m2 s-1. The threshold RH values for the transition were <5% RH for isoprene-derived SOM, 35-45% RH for SOM derived from α-pinene, toluene, m-xylene, and 1,3,5-trimethylbenzene, and >90% for β-caryophyllene-derived SOM. The transition RH for reactivity differed in all cases from the transition RH of a nonliquid to a liquid state. For instance, for α-pinene-derived SOM the transition for chemical reactivity of 35-45% RH can be compared to the nonliquid to liquid transition of 65-90% RH. These differences imply that chemical transport models of atmospheric chemistry should not use the SOM liquid to nonliquid phase transition as one-to-one surrogates of SOM reactivity.
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Affiliation(s)
- Yong Jie Li
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau , Avenida da Universidade, Taipa, Macau, China
| | - Pengfei Liu
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
| | - Zhaoheng Gong
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
| | - Yan Wang
- Department of Environmental Health, Harvard T.H. Chan School of Public Health , Boston, Massachusetts 02115, United States
| | - Adam P Bateman
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
| | - Clara Bergoend
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
- Department of Energy and Environment, National Institute of Applied Science of Lyon , Villeurbanne 69100, France
| | - Allan K Bertram
- Department of Chemistry, University of British Columbia , Vancouver, British Columbia V6T 1Z1, Canada
| | - Scot T Martin
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
- Department of Earth and Planetary Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
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19
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Ciuraru R, Fine L, Pinxteren MV, D’Anna B, Herrmann H, George C. Unravelling New Processes at Interfaces: Photochemical Isoprene Production at the Sea Surface. Environ Sci Technol 2015; 49:13199-205. [PMID: 26355365 PMCID: PMC4652275 DOI: 10.1021/acs.est.5b02388] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Isoprene is an important reactive gas that is produced mainly in terrestrial ecosystems but is also produced in marine ecosystems. In the marine environment, isoprene is produced in the seawater by various biological processes. Here, we show that photosensitized reactions involving the sea-surface microlayer lead to the production of significant amounts of isoprene. It is suggested that H-abstraction processes are initiated by photochemically excited dissolved organic matter which will the degrade fatty acids acting as surfactants. This chemical interfacial processing may represent a significant abiotic source of isoprene in the marine boundary layer.
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Affiliation(s)
- Raluca Ciuraru
- Université
de Lyon 1, Lyon, F-69626, France
- CNRS, UMR5256,
IRCELYON, Institut de Recherches sur la Catalyse et
l′Environnement de Lyon, Villeurbanne, F-69626, France
| | - Ludovic Fine
- Université
de Lyon 1, Lyon, F-69626, France
- CNRS, UMR5256,
IRCELYON, Institut de Recherches sur la Catalyse et
l′Environnement de Lyon, Villeurbanne, F-69626, France
| | - Manuela van Pinxteren
- Leibniz-Institut
für Troposphärenforschung e.V. (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany
| | - Barbara D’Anna
- Université
de Lyon 1, Lyon, F-69626, France
- CNRS, UMR5256,
IRCELYON, Institut de Recherches sur la Catalyse et
l′Environnement de Lyon, Villeurbanne, F-69626, France
| | - Hartmut Herrmann
- Leibniz-Institut
für Troposphärenforschung e.V. (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany
| | - Christian George
- Université
de Lyon 1, Lyon, F-69626, France
- CNRS, UMR5256,
IRCELYON, Institut de Recherches sur la Catalyse et
l′Environnement de Lyon, Villeurbanne, F-69626, France
- E-mail: . Phone: +33 4 72 44 54 92
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20
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Wong JPS, Lee AKY, Abbatt JPD. Impacts of Sulfate Seed Acidity and Water Content on Isoprene Secondary Organic Aerosol Formation. Environ Sci Technol 2015; 49:13215-13221. [PMID: 26460477 DOI: 10.1021/acs.est.5b02686] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The effects of particle-phase water and the acidity of pre-existing sulfate seed particles on the formation of isoprene secondary organic aerosol (SOA) was investigated. SOA was generated from the photo-oxidation of isoprene in a flow tube reactor at 70% relative humidity (RH) and room temperature in the presence of three different sulfate seeds (effloresced and deliquesced ammonium sulfate and ammonium bisulfate) under low NOx conditions. High OH exposure conditions lead to little isoprene epoxydiol (IEPOX) SOA being generated. The primary result is that particle-phase water had the largest effect on the amount of SOA formed, with 60% more SOA formation occurring with deliquesced ammonium sulfate seeds as compared to that on effloresced ones. The additional organic material was highly oxidized. Although the amount of SOA formed did not exhibit a dependence on the range of seed particle acidity examined, perhaps because of the low amount of IEPOX SOA, the levels of high-molecular-weight material increased with acidity. While the uptake of organics was partially reversible under drying, the results nevertheless indicate that particle-phase water enhanced the amount of organic aerosol material formed and that the RH cycling of sulfate particles may mediate the extent of isoprene SOA formation in the atmosphere.
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Affiliation(s)
- Jenny P S Wong
- Department of Chemistry, University of Toronto , 80 St. George Street , Toronto, Ontario, Canada M5S 3H6
| | - Alex K Y Lee
- Department of Chemistry, University of Toronto , 80 St. George Street , Toronto, Ontario, Canada M5S 3H6
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto , 80 St. George Street , Toronto, Ontario, Canada M5S 3H6
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21
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Muramoto S, Matsubara Y, Mwenda CM, Koeduka T, Sakami T, Tani A, Matsui K. Glutathionylation and Reduction of Methacrolein in Tomato Plants Account for Its Absorption from the Vapor Phase. Plant Physiol 2015; 169:1744-1754. [PMID: 26169680 PMCID: PMC4634080 DOI: 10.1104/pp.15.01045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 07/12/2015] [Indexed: 06/04/2023]
Abstract
A large portion of the volatile organic compounds emitted by plants are oxygenated to yield reactive carbonyl species, which have a big impact on atmospheric chemistry. Deposition to vegetation driven by the absorption of reactive carbonyl species into plants plays a major role in cleansing the atmosphere, but the mechanisms supporting this absorption have been little examined. Here, we performed model experiments using methacrolein (MACR), one of the major reactive carbonyl species formed from isoprene, and tomato (Solanum lycopersicum) plants. Tomato shoots enclosed in a jar with MACR vapor efficiently absorbed MACR. The absorption efficiency was much higher than expected from the gas/liquid partition coefficient of MACR, indicating that MACR was likely metabolized in leaf tissues. Isobutyraldehyde, isobutyl alcohol, and methallyl alcohol (MAA) were detected in the headspace and inside tomato tissues treated with MACR vapor, suggesting that MACR was enzymatically reduced. Glutathione (GSH) conjugates of MACR (MACR-GSH) and MAA (MAA-GSH) were also detected. MACR-GSH was essentially formed through spontaneous conjugation between endogenous GSH and exogenous MACR, and reduction of MACR-GSH to MAA-GSH was likely catalyzed by an NADPH-dependent enzyme in tomato leaves. Glutathionylation was the metabolic pathway most responsible for the absorption of MACR, but when the amount of MACR exceeded the available GSH, MACR that accumulated reduced photosynthetic capacity. In an experiment simulating the natural environment using gas flow, MACR-GSH and MAA-GSH accumulation accounted for 30% to 40% of the MACR supplied. These results suggest that MACR metabolism, especially spontaneous glutathionylation, is an essential factor supporting MACR absorption from the atmosphere by tomato plants.
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Affiliation(s)
- Shoko Muramoto
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
| | - Yayoi Matsubara
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
| | - Cynthia Mugo Mwenda
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
| | - Takao Koeduka
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
| | - Takuya Sakami
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
| | - Akira Tani
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
| | - Kenji Matsui
- Department of Biological Chemistry, Faculty of Agriculture, and Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan (S.M., Y.M. C.M.M., T.K., K.M.); andInstitute for Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan (T.S., A.T.)
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Kiminami H, Takeuchi K, Nakamura K, Abe Y, Lauwers P, Dierick W, Yoshino K, Suzuki S. Low Leachable Container System Consisting of a Polymer-Based Syringe with Chlorinated Isoprene Isobutene Rubber Plunger Stopper. PDA J Pharm Sci Technol 2015; 69:713-724. [PMID: 26659102 DOI: 10.5731/pdajpst.2015.01080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
UNLABELLED A 36 month leachable study on water for injection in direct contact within a polymer-based prefillable syringe consisting of a cyclo olefin polymer barrel, a chlorinated isoprene isobutene rubber plunger stopper, a polymer label attached on the barrel, and a secondary packaging was conducted at 25 ± 2 °C and 60 ± 5% relative humidity. Through the various comparison studies, no difference in the leachable amounts was observed between this polymer-based prefilled syringe and a glass bottle as a blank sample reference by 36 months. No influence on the leachables study outcome was noted from the printed label and/or label adhesive or from the secondary packaging. In an additional study, no acrylic acid used as the label adhesive leachable was detected by an extended storage for 45 months at 25 ± 2 °C and 60 ± 5% relative humidity as a worst case. To obtain more details, a comparison extractable study was conducted between a cyclo olefin polymer barrel and a glass barrel. In addition, chlorinated isoprene isobutene rubber and bromo isoprene isobutene rubber were compared. As a result, no remarkable difference was found in the organic extractables for syringe barrels. On the other hand, in the case of element extractable analysis, the values for the cyclo olefin polymer barrel were lower than that for the glass barrel. For the plunger stoppers, the chlorinated isoprene isobutene rubber applied in this study was showing a lower extractable profile as compared to the bromo isoprene isobutene rubber, both for organic and element extractables. In conclusion, the proposed polymer-based prefillable syringe system has great potential and represents a novel alternative that can achieve very low level extractable profiles and can bring additional value to the highly sensitive biotech drug market. LAY ABSTRACT A 36 month leachable study on water for injection in direct contact within a cyclo olefin polymer barrel and chlorinated isoprene isobutene rubber plunger stopper that has a polymer label attached to the barrel and is wrapped into a secondary packaging was conducted at 25 °C and 60% relative humidity. Through the various comparison studies, no difference in the leachable amounts was observed between polymer-based prefilled syringes and a glass bottle as a blank sample reference by 36 months. No influences on the leachables study outcome were noted from the secondary packaging. To obtain more details, a comparison extractable study was conducted between the cyclo olefin polymer and the glass barrel. In addition, chlorinated isoprene isobutene rubber and bromo isoprene isobutene rubber plunger stoppers were compared as well. As a result, no remarkable difference was found in the organic extractables for barrels. As for element extractable analysis, the values for the cyclo olefin polymer barrel were lower than that for the glass barrel. For the plunger stoppers, the chlorinated isoprene isobutene rubber applied in this study was showing a lower extractable profile as compared to the bromo isoprene isobutene rubber, both for organic and element extractables. In conclusion, the proposed polymer-based prefillable syringe system has great potential and represents a novel alternative that can achieve very low level extractable profiles and can bring additional value to the highly sensitive biotech drug market.
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Affiliation(s)
- Hideaki Kiminami
- Terumo Corporation, R&D Center, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan; and
| | - Katsuyuki Takeuchi
- Terumo Corporation, R&D Center, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan; and
| | - Koji Nakamura
- Terumo Corporation, R&D Center, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan; and
| | - Yoshihiko Abe
- Terumo Corporation, R&D Center, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan; and
| | | | | | - Keisuke Yoshino
- Terumo Corporation, R&D Center, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan; and
| | - Shigeru Suzuki
- Terumo Corporation, R&D Center, Nakai-machi, Ashigarakami-gun, Kanagawa, Japan; and
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23
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Boone EJ, Laskin A, Laskin J, Wirth C, Shepson PB, Stirm BH, Pratt KA. Aqueous Processing of Atmospheric Organic Particles in Cloud Water Collected via Aircraft Sampling. Environ Sci Technol 2015; 49:8523-30. [PMID: 26068538 DOI: 10.1021/acs.est.5b01639] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Cloudwater and below-cloud atmospheric particle samples were collected onboard a research aircraft during the Southern Oxidant and Aerosol Study (SOAS) over a forested region of Alabama in June 2013. The organic molecular composition of the samples was studied to gain insights into the aqueous-phase processing of organic compounds within cloud droplets. High resolution mass spectrometry (HRMS) with nanospray desorption electrospray ionization (nano-DESI) and direct infusion electrospray ionization (ESI) were utilized to compare the organic composition of the particle and cloudwater samples, respectively. Isoprene and monoterpene-derived organosulfates and oligomers were identified in both the particles and cloudwater, showing the significant influence of biogenic volatile organic compound oxidation above the forested region. While the average O:C ratios of the organic compounds were similar between the atmospheric particle and cloudwater samples, the chemical composition of these samples was quite different. Specifically, hydrolysis of organosulfates and formation of nitrogen-containing compounds were observed for the cloudwater when compared to the atmospheric particle samples, demonstrating that cloud processing changes the composition of organic aerosol.
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Affiliation(s)
- Eric J Boone
- †Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Alexander Laskin
- ‡Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Julia Laskin
- §Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | | | | | - Brian H Stirm
- ∇Department of Aviation Technology, Purdue University, West Lafayette, Indiana 47907, United States
| | - Kerri A Pratt
- †Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
- ○Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
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24
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Kipnusu WK, Elmahdy MM, Mapesa EU, Zhang J, Böhlmann W, Smilgies DM, Papadakis CM, Kremer F. Structure and Dynamics of Asymmetric Poly(styrene-b-1,4-isoprene) Diblock Copolymer under 1D and 2D Nanoconfinement. ACS Appl Mater Interfaces 2015; 7:12328-12338. [PMID: 25660102 DOI: 10.1021/am506848s] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The impact of 1- and 2-dimensional (2D) confinement on the structure and dynamics of poly(styrene-b-1,4-isoprene) P(S-b-I) diblock copolymer is investigated by a combination of Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Grazing-Incidence Small-Angle X-ray Scattering (GISAXS), and Broadband Dielectric Spectroscopy (BDS). 1D confinement is achieved by spin coating the P(S-b-I) to form nanometric thin films on silicon substrates, while in the 2D confinement, the copolymer is infiltrated into cylindrical anodized aluminum oxide (AAO) nanopores. After dissolving the AAO matrix having mean pore diameter of 150 nm, the SEM images of the exposed P(S-b-I) show straight nanorods. For the thin films, GISAXS and AFM reveal hexagonally packed cylinders of PS in a PI matrix. Three dielectrically active relaxation modes assigned to the two segmental modes of the styrene and isoprene blocks and the normal mode of the latter are studied selectively by BDS. The dynamic glass transition, related to the segmental modes of the styrene and isoprene blocks, is independent of the dimensionality and the finite sizes (down to 18 nm) of confinement, but the normal mode is influenced by both factors with 2D geometrical constraints exerting greater impact. This reflects the considerable difference in the length scales on which the two kinds of fluctuations take place.
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Affiliation(s)
- Wycliffe K Kipnusu
- †Institute of Experimental Physics I, University of Leipzig, Linnéstraße 5, 04103 Leipzig, Germany
| | - Mahdy M Elmahdy
- †Institute of Experimental Physics I, University of Leipzig, Linnéstraße 5, 04103 Leipzig, Germany
- ‡Department of Physics, Mansoura University, Mansoura 35516, Egypt
| | - Emmanuel U Mapesa
- †Institute of Experimental Physics I, University of Leipzig, Linnéstraße 5, 04103 Leipzig, Germany
| | - Jianqi Zhang
- ¶Physik-Department, Physik weicher Materie, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
| | - Winfried Böhlmann
- §Institute for Experimental Physics II, University of Leipzig, Linnéstraße 5, 04103 Leipzig, Germany
| | - Detlef-M Smilgies
- ∥Cornell High Energy Synchrotron Source (CHESS), Wilson Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Christine M Papadakis
- ¶Physik-Department, Physik weicher Materie, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
| | - Friedrich Kremer
- †Institute of Experimental Physics I, University of Leipzig, Linnéstraße 5, 04103 Leipzig, Germany
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25
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Okamoto K, Hiramatsu M, Hino T, Otake T, Okamoto T, Miyamoto H, Honma M, Watanabe N. Evaporation characteristics of ETBE-blended gasoline. J Hazard Mater 2015; 287:151-161. [PMID: 25644031 DOI: 10.1016/j.jhazmat.2015.01.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 01/07/2015] [Accepted: 01/08/2015] [Indexed: 06/04/2023]
Abstract
To reduce greenhouse gas emissions, which contribute to global warming, production of gasoline blended with ethyl tert-buthyl ether (ETBE) is increasing annually. The flash point of ETBE is higher than that of gasoline, and blending ETBE into gasoline will change the flash point and the vapor pressure. Therefore, it is expected that the fire hazard caused by ETBE-blended gasoline would differ from that caused by normal gasoline. The aim of this study was to acquire the knowledge required for estimating the fire hazard of ETBE-blended gasoline. Supposing that ETBE-blended gasoline was a two-component mixture of gasoline and ETBE, we developed a prediction model that describes the vapor pressure and flash point of ETBE-blended gasoline in an arbitrary ETBE blending ratio. We chose 8-component hydrocarbon mixture as a model gasoline, and defined the relation between molar mass of gasoline and mass loss fraction. We measured the changes in the vapor pressure and flash point of gasoline by blending ETBE and evaporation, and compared the predicted values with the measured values in order to verify the prediction model. The calculated values of vapor pressures and flash points corresponded well to the measured values. Thus, we confirmed that the change in the evaporation characteristics of ETBE-blended gasoline by evaporation could be predicted by the proposed model. Furthermore, the vapor pressure constants of ETBE-blended gasoline were obtained by the model, and then the distillation curves were developed.
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Affiliation(s)
- Katsuhiro Okamoto
- National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan.
| | - Muneyuki Hiramatsu
- Yamanashi Prefectural Police H.Q., 312-4 Kubonakajima, Isawa-cho, Usui, Yamanashi 406-0036, Japan
| | - Tomonori Hino
- Metropolitan Police Department, 2-1-1 Kasumigaseki, Chiyoda-ku, Tokyo 100-8929, Japan
| | - Takuma Otake
- Metropolitan Police Department, 2-1-1 Kasumigaseki, Chiyoda-ku, Tokyo 100-8929, Japan
| | - Takashi Okamoto
- National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan
| | - Hiroki Miyamoto
- National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan
| | - Masakatsu Honma
- National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan
| | - Norimichi Watanabe
- National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan
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Vural M, Behrens AM, Ayyub OB, Ayoub JJ, Kofinas P. Sprayable elastic conductors based on block copolymer silver nanoparticle composites. ACS Nano 2015; 9:336-44. [PMID: 25491507 PMCID: PMC4310637 DOI: 10.1021/nn505306h] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 12/09/2014] [Indexed: 05/18/2023]
Abstract
Block copolymer silver nanoparticle composite elastic conductors were fabricated through solution blow spinning and subsequent nanoparticle nucleation. The reported technique allows for conformal deposition onto nonplanar substrates. We additionally demonstrated the ability to tune the strain dependence of the electrical properties by adjusting nanoparticle precursor concentration or localized nanoparticle nucleation. The stretchable fiber mats were able to display electrical conductivity values as high as 2000 ± 200 S/cm with only a 12% increase in resistance after 400 cycles of 150% strain. Stretchable elastic conductors with similar and higher bulk conductivity have not achieved comparable stability of electrical properties. These unique electromechanical characteristics are primarily the result of structural changes during mechanical deformation. The versatility of this approach was demonstrated by constructing a stretchable light emitting diode circuit and a strain sensor on planar and nonplanar substrates.
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Affiliation(s)
- Mert Vural
- Department of Materials Science and Engineering and Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Adam M. Behrens
- Department of Materials Science and Engineering and Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Omar B. Ayyub
- Department of Materials Science and Engineering and Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Joseph J. Ayoub
- Department of Materials Science and Engineering and Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Peter Kofinas
- Department of Materials Science and Engineering and Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
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Wang Z, Jiang F, Zhang Y, You Y, Wang Z, Guan Z. Bioinspired design of nanostructured elastomers with cross-linked soft matrix grafting on the oriented rigid nanofibers to mimic mechanical properties of human skin. ACS Nano 2015; 9:271-8. [PMID: 25551474 DOI: 10.1021/nn506960f] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Human skin exhibits highly nonlinear elastic properties that are essential to its physiological functions. It is soft at low strain but stiff at high strain, thereby protecting internal organs and tissues from mechanical trauma. However, to date, the development of materials to mimic the unique mechanical properties of human skin is still a great challenge. Here we report a bioinspired design of nanostructured elastomers combining two abundant plant-based biopolymers, stiff cellulose and elastic polyisoprene (natural rubber), to mimic the mechanical properties of human skin. The nanostructured elastomers show highly nonlinear mechanical properties closely mimicking that of human skin. Importantly, the mechanical properties of these nanostructured elastomers can be tuned by adjusting cellulose content, providing the opportunity to synthesize materials that mimic the mechanical properties of different types of skins. Given the simplicity, efficiency, and tunability, this design may provide a promising strategy for creating artificial skin for both general mechanical and biomedical applications.
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Affiliation(s)
- Zhongkai Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China , Hefei, Anhui Province 230026, P.R. China
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28
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Liu Y, Kuwata M, Strick BF, Geiger FM, Thomson RJ, McKinney KA, Martin ST. Uptake of epoxydiol isomers accounts for half of the particle-phase material produced from isoprene photooxidation via the HO2 pathway. Environ Sci Technol 2015; 49:250-8. [PMID: 25375412 DOI: 10.1021/es5034298] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The oxidation of isoprene is a globally significant source of secondary organic material (SOM) of atmospheric particles. The relative importance of different parallel pathways, however, remains inadequately understood and quantified. SOM production from isoprene photooxidation was studied under hydroperoxyl-dominant conditions for <5% relative humidity and at 20 °C in the presence of highly acidic to completely neutralized sulfate particles. Isoprene photooxidation was separated from SOM production by using two continuously mixed flow reactors connected in series and operated at steady state. Two online mass spectrometers separately sampled the gas and particle phases in the reactor outflow. The loss of specific gas-phase species as contributors to the production of SOM was thereby quantified. The produced SOM mass concentration was directly proportional to the loss of isoprene epoxydiol (IEPOX) isomers from the gas phase. IEPOX isomers lost from the gas phase accounted for (46 ± 11)% of the produced SOM mass concentration. The IEPOX isomers comprised (59 ± 21)% (molecular count) of the loss of monitored gas-phase species. The implication is that for the investigated reaction conditions the SOM production pathways tied to IEPOX isomers accounted for half of the SOM mass concentration.
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Affiliation(s)
- Yingjun Liu
- School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
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29
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Srivastva N, Shukla AK, Singh RS, Upadhyay SN, Dubey SK. Characterization of bacterial isolates from rubber dump site and their use in biodegradation of isoprene in batch and continuous bioreactors. Bioresour Technol 2015; 188:84-91. [PMID: 25662189 DOI: 10.1016/j.biortech.2015.01.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 01/05/2015] [Accepted: 01/06/2015] [Indexed: 05/07/2023]
Abstract
Bacterial isolates from contaminated soil of a waste rubber dumping site were isolated and characterized using biochemical and molecular approaches. Isoprene degradation kinetics in batch mode (isoprene concentration: 100-1000 ppm) revealed the degradation efficiency of isolates as: Pseudomonas sp. (83%)>Alcaligenes sp. (70%)>Klebsiella sp. (68.5%). The most efficient isolate Pseudomonas sp. was finally inoculated in a specifically designed bioreactor system comprising a bioscrubber and a biofilter packed with polyurethane foam connected in series. The bioscrubber and biofilter units when operated in a series showed more than 90% removal efficiency up to the inlet loading rate (IL) of 371.1g/m(3)/h. Maximum elimination capacity (EC) of biofilter was found to be an order of magnitude greater than that for bioscrubber. Oxidative cleavage of the double bond of isoprene has been revealed through IR spectra of the leachate.
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Affiliation(s)
- Navnita Srivastva
- Department of Botany, Faculty of Science, Banaras Hindu University, Varanasi 221005, India
| | - Awadhesh Kumar Shukla
- Department of Botany, Faculty of Science, Banaras Hindu University, Varanasi 221005, India
| | - Ram Sharan Singh
- Department of Chemical Engineering and Technology, Institute of Technology, Banaras Hindu University, Varanasi 221005, India
| | - Siddh Nath Upadhyay
- Department of Chemical Engineering and Technology, Institute of Technology, Banaras Hindu University, Varanasi 221005, India
| | - Suresh Kumar Dubey
- Department of Botany, Faculty of Science, Banaras Hindu University, Varanasi 221005, India.
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Barlow A, Butler A, Mason S, Zero D. Exploratory Randomized Clinical Trial of an Experimental Gel-to-Foam Fluoride Dentifrice Formulation Using an In Situ Caries Model. J Clin Dent 2015; 26:33-38. [PMID: 26349123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To evaluate the in situ caries performance and safety of two experimental fluoride dentifrice formulations (1450 ppm fluoride) with and without 2% isopentane as an excipient, in comparison to a positive control, currently marketed dentifrice (1450 ppm fluoride) and a negative control dentifrice (0 ppm fluoride). METHODS This was a single-center, examiner-blind, randomized, controlled, four-treatment cross-over study. During each treatment period, the subject wore a modified mandibular partial denture fitted with two gauze-covered, partially demineralized human enamel specimens, and brushed at home for one timed minute, twice daily, for two weeks. At the end of each treatment period, the enamel specimens were removed from the dentures for analysis. During the week between treatment periods, subjects returned to their usual dental hygiene practices for four to five days, received a dental prophylaxis, and used a study-designated non-fluoride dentifrice for two to three days before starting the next treatment. Treatment effect on enamel specimen remineralization was assessed by surface microhardness (SMH). Enamel fluoride uptake was assessed using microdrill enamel biopsy. RESULTS All fluoride-containing dentifrices demonstrated significant, superior SMH recovery and levels of fluoride uptake compared to the negative control dentifrice. No significant differences were observed for either efficacy variable between the experimental dentifrice formulations and the positive control dentifrice. No significant difference was observed between the 2% isopentane dentifrice and the 0% isopentane dentifrice for SMH recovery. CONCLUSION The addition of 2% isopentane did not positively or negatively affect fluoride efficacy in this model.
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Huang R, Liu HY, Zhang BS, Sun XY, Liang CH, Su DS, Zong BN, Rong JF. Phosphate-modified carbon nanotubes in the oxidative dehydrogenation of isopentanes. ChemSusChem 2014; 7:3476-3482. [PMID: 25213438 DOI: 10.1002/cssc.201402457] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Indexed: 06/03/2023]
Abstract
Ketonic/quinonic C=O groups on the surface of a carbon matrix are capable of abstracting hydrogen in C=H bonds from hydrocarbons and enable them to selectively convert into corresponding unsaturated hydrocarbons; this process is the oxidative dehydrogenation (ODH) reaction. However, a variety of inevitable defects or graphene edges and other oxygen-containing groups on the carbon matrix are detrimental to the selective production of alkenes due to their high activity towards overoxidation. Herein, we show that phosphate can not only impede the total oxidation but also cover the selective C=O groups, hence allowing its use as a modulator to defects and oxygen-containing functional groups on the multiwalled carbon nanotubes, regulating the distribution of active sites and related catalytic targets.
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Affiliation(s)
- Rui Huang
- Lab of Advanced Materials & Catalytic Engineering, Dalian University of Technology, No. 2 Linggong Road, Dalian 116024 (PR China); Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Science, No. 72 Wenhua Road, Shenyang 110016 (PR China)
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32
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Genard-Zielinski AC, Ormeño E, Boissard C, Fernandez C. Isoprene emissions from downy oak under water limitation during an entire growing season: what cost for growth? PLoS One 2014; 9:e112418. [PMID: 25383554 PMCID: PMC4226567 DOI: 10.1371/journal.pone.0112418] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 10/15/2014] [Indexed: 12/02/2022] Open
Abstract
Increases in the production of terpene- and phenolic-like compounds in plant species under abiotic stress conditions have been interpreted in physiological studies as a supplementary defense system due to their capacity to limit cell oxidation. From an ecological perspective however, these increases are only expected to confer competitive advantages if they do not imply a significant cost for the plant, that is, growth reduction. We investigated shifts of isoprene emissions, and to a lesser extent phenolic compound concentration, of Quercus pubescens Willd. from early leaf development to leaf senescence under optimal watering (control: C), mild and severe water stress (MS, SS). The impact of water stress was concomitantly assessed on plant physiological (chlorophyll fluorescence, stomatal conductance, net photosynthesis, water potential) functional (relative leaf water content, leaf mass per area ratio) and growth (aerial and root biomass) traits. Growth changes allowed to estimate the eventual costs related to the production of isoprene and phenolics. The total phenolic content was not modified under water stress whereas isoprene emissions were promoted under MS over the entire growing cycle despite the decline of Pn by 35%. Under SS, isoprene emissions remained similar to C all over the study despite the decline of Pn by 47% and were thereby clearly uncoupled to Pn leading to an overestimation of the isoprene emission factor by 44%. Under SS, maintenance of isoprene emissions and phenolic compound concentration resulted in very significant costs for the plants as growth rates were very significantly reduced. Under MS, increases of isoprene emission and maintenance of phenolic compound concentration resulted in moderate growth reduction. Hence, it is likely that investment in isoprene emissions confers Q. pubescens an important competitive advantage during moderate but not severe periods of water scarcity. Consequences of this response for air quality in North Mediterranean areas are also discussed.
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Affiliation(s)
- Anne-Cyrielle Genard-Zielinski
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) Aix Marseille Université, CNRS, IRD, Avignon Université, Technopôle Arbois-Méditerranée, France
- Laboratoire des Sciences du Climat et de l’Environnement (LSCE-IPSL), Unité Mixte CEA-CNRS-UVSQ (Commissariat à l’Energie Atomique, Centre National de la Recherche Scientifique, Université de Versailles Saint-Quentin-en-Yvelines), Gif-sur-Yvette, France
| | - Elena Ormeño
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) Aix Marseille Université, CNRS, IRD, Avignon Université, Technopôle Arbois-Méditerranée, France
| | - Christophe Boissard
- Laboratoire des Sciences du Climat et de l’Environnement (LSCE-IPSL), Unité Mixte CEA-CNRS-UVSQ (Commissariat à l’Energie Atomique, Centre National de la Recherche Scientifique, Université de Versailles Saint-Quentin-en-Yvelines), Gif-sur-Yvette, France
| | - Catherine Fernandez
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) Aix Marseille Université, CNRS, IRD, Avignon Université, Technopôle Arbois-Méditerranée, France
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Lin YH, Budisulistiorini SH, Chu K, Siejack RA, Zhang H, Riva M, Zhang Z, Gold A, Kautzman KE, Surratt JD. Light-absorbing oligomer formation in secondary organic aerosol from reactive uptake of isoprene epoxydiols. Environ Sci Technol 2014; 48:12012-21. [PMID: 25226366 DOI: 10.1021/es503142b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Secondary organic aerosol (SOA) produced from reactive uptake and multiphase chemistry of isoprene epoxydiols (IEPOX) has been found to contribute substantially (upward of 33%) to the fine organic aerosol mass over the Southeastern U.S. Brown carbon (BrC) in rural areas of this region has been linked to secondary sources in the summer when the influence of biomass burning is low. We demonstrate the formation of light-absorbing (290 < λ < 700 nm) SOA constituents from reactive uptake of trans-β-IEPOX onto preexisting sulfate aerosols as a potential source of secondary BrC. IEPOX-derived BrC generated in controlled chamber experiments under dry, acidic conditions has an average mass absorption coefficient of ∼ 300 cm(2) g(-1). Chemical analyses of SOA constituents using UV-visible spectroscopy and high-resolution mass spectrometry indicate the presence of highly unsaturated oligomeric species with molecular weights separated by mass units of 100 (C5H8O2) and 82 (C5H6O) coincident with the observations of enhanced light absorption, suggesting such oligomers as chromophores, and potentially explaining one source of humic-like substances (HULIS) ubiquitously present in atmospheric aerosol. Similar light-absorbing oligomers were identified in fine aerosol collected in the rural Southeastern U.S., supporting their atmospheric relevance and revealing a previously unrecognized source of oligomers derived from isoprene that contributes to ambient fine aerosol mass.
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Affiliation(s)
- Ying-Hsuan Lin
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States
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34
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Gao YQ, Zhang S, Wang P, Xu S, Wu K, Mou W. Construction and characterization on composite electrospinning fibers doped with iridium complex owing fluorine atoms in its auxiliary ligand. Spectrochim Acta A Mol Biomol Spectrosc 2014; 131:518-525. [PMID: 24840494 DOI: 10.1016/j.saa.2014.04.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/14/2014] [Accepted: 04/22/2014] [Indexed: 06/03/2023]
Abstract
The authors synthesized a fluorine-containing Ir(III) complex Ir(PTZ)2(HFD) and the corresponding composite electrospinning fibers PVP@Ir(PTZ)2(HFD), where PTZ, HFD and PVP stood for 2-phenylbenzo[d]thiazole, 1,1,1,5,5,5-hexafluoropentane-2,4-dione and poly(vinylpyrrolidone), respectively. The molecular structure of the Ir(III) complex was confirmed by its single crystal analysis, which suggested that Ir(PTZ)2(HFD) molecules crystallized as monoclinic system with two molecules in each unit cell. Density functional theory calculation on the crystal revealed that the onset electronic transitions possessed a mixed character of metal-to-ligand-charge-transfer (MLCT) and ligand-to-ligand-charge-transfer (LLCT). Ir(PTZ)2(HFD) was then doped into electrospinning fibers so that the photophysical comparison between bulk Ir(PTZ)2(HFD) and composite samples could be performed. It was found that both face-to-face π-π attraction in crystal and the immobilization in PVP host could improve photoluminescence performance by restraining the geometric relaxation of MLCT excited state, showing emission blue shift, longer excited state lifetime and improved photostability.
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Affiliation(s)
- Yu-Qian Gao
- College of Life Sciences, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China; Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Henan Agriculture University, Henan 450002, China
| | - Shimin Zhang
- College of Life Sciences, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China; Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Henan Agriculture University, Henan 450002, China
| | - Pengju Wang
- College of Life Sciences, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China; Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Henan Agriculture University, Henan 450002, China
| | - Shuxia Xu
- College of Life Sciences, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China; Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Henan Agriculture University, Henan 450002, China
| | - Kun Wu
- College of Life Sciences, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China; Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Henan Agriculture University, Henan 450002, China.
| | - Wanzhi Mou
- College of Chemistry and Molecular Engineering, Tsinghua University, Beijing 100871, China
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35
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Abstract
Although Maillard reaction plays a pivotal role during preparation of food, only few investigations concerning the role of carbohydrate degradation in beer aging have been carried out. The formation of Maillard specific precursor structures and their follow-up products during degradation of low molecular carbohydrate dextrins in the presence of proline and lysine was studied in model incubations and in beer. Twenty-one α-dicarbonyl compounds were identified and quantitated as reactive intermediates. The oxidative formation of 3-deoxypentosone as the precursor of furfural from oligosaccharides was verified. N-Carboxymethylproline and N-formylproline were established as novel proline derived Maillard advanced glycation end products. Formation of N-carboxymethylproline and furfural responded considerably to the presence of oxygen and was positively correlated to aging of Pilsner type beer. The present study delivers an in-depth view on the mechanisms behind the formation of beer relevant aging parameters.
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Affiliation(s)
- Stefan Rakete
- Food Chemistry, Institute of Chemistry, Martin-Luther-University Halle-Wittenberg , Kurt-Mothes-Straße 2, 06120 Halle/Saale, Germany
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36
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Gaston CJ, Riedel TP, Zhang Z, Gold A, Surratt JD, Thornton JA. Reactive uptake of an isoprene-derived epoxydiol to submicron aerosol particles. Environ Sci Technol 2014; 48:11178-86. [PMID: 25207961 DOI: 10.1021/es5034266] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The reactive uptake of isoprene-derived epoxydiols (IEPOX) is thought to be a significant source of atmospheric secondary organic aerosol (SOA). However, the IEPOX reaction probability (γIEPOX) and its dependence upon particle composition remain poorly constrained. We report measurements of γIEPOX for trans-β-IEPOX, the predominant IEPOX isomer, on submicron particles as a function of composition, acidity, and relative humidity (RH). Particle acidity had the strongest effect. γIEPOX is more than 500 times greater on ammonium bisulfate (γ ∼ 0.05) than on ammonium sulfate (γ ≤ 1 × 10(-4)). We could accurately predict γIEPOX using an acid-catalyzed, epoxide ring-opening mechanism and a high Henry's law coefficient (1.7 × 10(8) M/atm). Suppression of γIEPOX was observed on particles containing both ammonium bisulfate and poly(ethylene glycol) (PEG-300), likely due to diffusion and solubility limitations within a PEG-300 coating, suggesting that IEPOX uptake could be self-limiting. Using the measured uptake kinetics, the predicted atmospheric lifetime of IEPOX is a few hours in the presence of highly acidic particles (pH < 0) but is greater than 25 h on less acidic particles (pH > 3). This work highlights the importance of aerosol acidity for accurately predicting the fate of IEPOX and anthropogenically influenced biogenic SOA formation.
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Affiliation(s)
- Cassandra J Gaston
- Department of Atmospheric Sciences, University of Washington , Seattle, Washington 98195 United States
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37
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He QF, Ding X, Wang XM, Yu JZ, Fu XX, Liu TY, Zhang Z, Xue J, Chen DH, Zhong LJ, Donahue NM. Organosulfates from pinene and isoprene over the Pearl River Delta, South China: seasonal variation and implication in formation mechanisms. Environ Sci Technol 2014; 48:9236-9245. [PMID: 25072510 DOI: 10.1021/es501299v] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Biogenic organosulfates (OSs) are important markers of secondary organic aerosol (SOA) formation involving cross reactions of biogenic precursors (terpenoids) with anthropogenic pollutants. Until now, there has been rare information about biogenic OSs in the air of highly polluted areas. In this study, fine particle (PM2.5) samples were separately collected in daytime and nighttime from summer to fall 2010 at a site in the central Pearl River Delta (PRD), South China. Pinene-derived nitrooxy-organosulfates (pNOSs) and isoprene-derived OSs (iOSs) were quantified using a liquid chromatograph (LC) coupled with a tandem mass spectrometer (MS/MS) operated in negative electrospray ionization (ESI) mode. The pNOSs with MW 295 exhibited higher levels in fall (151 ± 86.9 ng m(-3)) than summer (52.4 ± 34.0 ng m(-3)), probably owing to the elevated levels of NOx and sulfate in fall when air masses mainly passed through city clusters in the PRD and biomass burning was enhanced. In contrast to observations elsewhere where higher levels occurred at nighttime, pNOS levels in the PRD were higher during the daytime in both seasons, indicating that pNOS formation was likely driven by photochemistry over the PRD. This conclusion is supported by several lines of evidence: the specific pNOS which could be formed through both daytime photochemistry and nighttime NO3 chemistry exhibited no day-night variation in abundance relative to other pNOS isomers; the production of the hydroxynitrate that is the key precursor for this specific pNOS was found to be significant through photochemistry but negligible through NO3 chemistry based on the mechanisms in the Master Chemical Mechanism (MCM). For iOSs, 2-methyltetrol sulfate ester which could be formed from isoprene-derived epoxydiols (IEPOX) under low-NOx conditions showed low concentrations (below the detection limit to 2.09 ng m(-3)), largely due to the depression of IEPOX formation by the high NOx levels over the PRD.
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Affiliation(s)
- Quan-Fu He
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
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38
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Vickers CE, Bongers M, Liu Q, Delatte T, Bouwmeester H. Metabolic engineering of volatile isoprenoids in plants and microbes. Plant Cell Environ 2014; 37:1753-75. [PMID: 24588680 DOI: 10.1111/pce.12316] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 02/18/2014] [Accepted: 02/18/2014] [Indexed: 05/09/2023]
Abstract
The chemical properties and diversity of volatile isoprenoids lends them to a broad variety of biological roles. It also lends them to a host of biotechnological applications, both by taking advantage of their natural functions and by using them as industrial chemicals/chemical feedstocks. Natural functions include roles as insect attractants and repellents, abiotic stress protectants in pathogen defense, etc. Industrial applications include use as pharmaceuticals, flavours, fragrances, fuels, fuel additives, etc. Here we will examine the ways in which researchers have so far found to exploit volatile isoprenoids using biotechnology. Production and/or modification of volatiles using metabolic engineering in both plants and microorganisms are reviewed, including engineering through both mevalonate and methylerythritol diphosphate pathways. Recent advances are illustrated using several case studies (herbivores and bodyguards, isoprene, and monoterpene production in microbes). Systems and synthetic biology tools with particular utility for metabolic engineering are also reviewed. Finally, we discuss the practical realities of various applications in modern biotechnology, explore possible future applications, and examine the challenges of moving these technologies forward so that they can deliver tangible benefits. While this review focuses on volatile isoprenoids, many of the engineering approaches described here are also applicable to non-isoprenoid volatiles and to non-volatile isoprenoids.
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Affiliation(s)
- Claudia E Vickers
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland, 4072, Australia
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39
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Potosnak MJ. Including the interactive effect of elevated CO₂ concentration and leaf temperature in global models of isoprene emission. Plant Cell Environ 2014; 37:1723-1726. [PMID: 24934668 DOI: 10.1111/pce.12385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- Mark J Potosnak
- Department of Environmental Science and Studies, DePaul University, Chicago, IL, 60614, USA
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40
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Sharkey TD, Monson RK. The future of isoprene emission from leaves, canopies and landscapes. Plant Cell Environ 2014; 37:1727-40. [PMID: 24471530 DOI: 10.1111/pce.12289] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 05/09/2023]
Abstract
Isoprene emission from plants plays a dominant role in atmospheric chemistry. Predicting how isoprene emission may change in the future will help predict changes in atmospheric oxidant, greenhouse gas and secondary organic aerosol concentrations in the future atmosphere. At the leaf-scale, an increase in isoprene emission with increasing temperature is offset by a reduction in isoprene emission rate caused by increased CO₂. At the canopy scale, increased leaf area index in elevated CO₂ can offset the reduction in leaf-scale isoprene emission caused by elevated CO₂. At the landscape scale, a reduction in forest coverage may decrease, while forest fertilization and community composition dynamics are likely to cause an increase in the global isoprene emission rate. Here we review the potential for changes in the isoprene emission rate at all of these scales. When considered together, it is likely that these interacting effects will result in an increase in the emission of the most abundant plant volatile, isoprene, from the biosphere to the atmosphere in the future.
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Affiliation(s)
- Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
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41
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Choi JH, Suzuki T, Okumura H, Noguchi K, Kondo M, Nagai K, Hirai H, Kawagishi H. Endoplasmic reticulum stress suppressive compounds from the edible mushroom Mycoleptodonoides aitchisonii. J Nat Prod 2014; 77:1729-1733. [PMID: 24988471 DOI: 10.1021/np500075m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Two novel compounds, 1 and 7, along with six known compounds (2-6 and 8), were isolated from the edible mushroom Mycoleptodonoides aitchisonii (bunaharitake in Japanese). The structures of the new compounds were determined by the interpretation of spectroscopic data. Compounds 1-4 and 6-8 showed protective activity against endoplasmic reticulum stress-dependent cell death.
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Affiliation(s)
- Jae-Hoon Choi
- Research Institute of Green Science and Technology, Shizuoka University , 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
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42
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Ramos KRM, Valdehuesa KNG, Liu H, Nisola GM, Lee WK, Chung WJ. Combining De Ley-Doudoroff and methylerythritol phosphate pathways for enhanced isoprene biosynthesis from D-galactose. Bioprocess Biosyst Eng 2014; 37:2505-13. [PMID: 24928200 DOI: 10.1007/s00449-014-1228-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 05/25/2014] [Indexed: 01/17/2023]
Abstract
An engineered Escherichia coli strain was developed for enhanced isoprene production using D-galactose as substrate. Isoprene is a valuable compound that can be biosynthetically produced from pyruvate and glyceraldehyde-3-phosphate (G3P) through the methylerythritol phosphate pathway (MEP). The Leloir and De Ley-Doudoroff (DD) pathways are known existing routes in E. coli that can supply the MEP precursors from D-galactose. The DD pathway was selected as it is capable of supplying equimolar amounts of pyruvate and G3P simultaneously. To exclusively direct D-galactose toward the DD pathway, an E. coli ΔgalK strain with blocked Leloir pathway was used as the host. To obtain a fully functional DD pathway, a dehydrogenase encoding gene (gld) was recruited from Pseudomonas syringae to catalyze D-galactose conversion to D-galactonate. Overexpressions of endogenous genes known as MEP bottlenecks, and a heterologous gene, were conducted to enhance and enable isoprene production, respectively. Growth test confirmed a functional DD pathway concomitant with equimolar generation of pyruvate and G3P, in contrast to the wild-type strain where G3P was limiting. Finally, the engineered strain with combined DD-MEP pathway exhibited the highest isoprene production. This suggests that the equimolar pyruvate and G3P pools resulted in a more efficient carbon flux toward isoprene production. This strategy provides a new platform for developing improved isoprenoid producing strains through the combined DD-MEP pathway.
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Affiliation(s)
- Kristine Rose M Ramos
- Department of Energy and Biotechnology (DEB), Energy and Environment Fusion Technology Center (E2FTC), Myongji University, 116 Myongji-ro, Cheoin-gu, Yongin-si, Gyeonggi-do, 449-728, Republic of Korea
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43
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Guseva DV, Komarov PV, Lyulin AV. Molecular-dynamics simulations of thin polyisoprene films confined between amorphous silica substrates. J Chem Phys 2014; 140:114903. [PMID: 24655202 DOI: 10.1063/1.4868231] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- D V Guseva
- Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
| | - P V Komarov
- Department of Theoretical Physics, Tver State University, Sadovyj per. 35, 170002 Tver, Russia and Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova st. 28, 119991 Moscow, Russia
| | - Alexey V Lyulin
- Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
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44
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Xu L, Kollman MS, Song C, Shilling JE, Ng NL. Effects of NOx on the volatility of secondary organic aerosol from isoprene photooxidation. Environ Sci Technol 2014; 48:2253-62. [PMID: 24471688 DOI: 10.1021/es404842g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effects of NOx on the volatility of the secondary organic aerosol (SOA) formed from isoprene photooxidation are investigated in environmental chamber experiments. Two types of experiments are performed. In HO2-dominant experiments, organic peroxy radicals (RO2) primarily react with HO2. In mixed experiments, RO2 reacts through multiple pathways, including with NO, NO2, and HO2. The volatility and oxidation state of isoprene SOA are sensitive to and exhibit a nonlinear dependence on NOx levels. Depending on the NOx levels, the SOA formed in mixed experiments can be of similar or lower volatility compared to that formed in HO2-dominant experiments. The dependence of SOA yield, volatility, and oxidation state on the NOx level likely arises from gas-phase RO2 chemistry and succeeding particle-phase oligomerization reactions. The NOx level also plays a strong role in SOA aging. While the volatility of SOA in mixed experiments does not change substantially over time, SOA becomes less volatile and more oxidized as oxidation progresses in HO2-dominant experiments.
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Affiliation(s)
- Lu Xu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States
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45
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Packard E, Pascoe DD, Maddaluno J, Gonçalves TP, Harrowven DC. Organoytterbium ate complexes extend the value of cyclobutenediones as isoprene equivalents. Angew Chem Int Ed Engl 2013; 52:13076-9. [PMID: 24155206 PMCID: PMC4285119 DOI: 10.1002/anie.201307193] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Indexed: 11/17/2022]
Abstract
Changing course: While organolithium and Grignard reagents favor addition to C1 of A (R=Me), the corresponding organoytterbium reagents add to C2 (R=tBu). Computational studies provide insights into the nature of organoytterbium species and their reactivity, and a total synthesis of (-)-mansonone B illustrates the utility of the method in terpenoid synthesis. Tf=trifluoromethanesulfonyl.
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Affiliation(s)
- Emma Packard
- Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom)
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46
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Abstract
Recent laboratory and field work has shown that isoprene-derived epoxides (IEPOX) are crucial intermediates that can explain the existence of a variety of compounds found in ambient secondary organic aerosol (SOA). However, IEPOX species are also able to undergo gas phase oxidation, which competes with the aerosol phase processing of IEPOX. In order to better quantify the atmospheric fate of IEPOX, the gas phase OH reaction rate constants and product formation mechanisms have been determined using a flow tube chemical ionization mass spectrometry technique. The new OH rate constants are generally larger than previous estimations and some features of the product mechanism are well predicted by the Master Chemical Mechanism Version 3.2 (MCM v3.2), while other features are at odds with MCM v3.2. Using a previously proposed kinetic model for the quantitative prediction of the atmospheric fate of IEPOX, it is found that gas phase OH reaction is an even more dominant fate for chemical processing of IEPOX than previously suggested. The present results suggest that aerosol phase processing of IEPOX will be competitive with gas phase OH oxidation only under SOA conditions of high liquid water content and low pH.
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Affiliation(s)
- Michael I Jacobs
- Department of Chemistry and Biochemistry, Oberlin College , 119 Woodland Street, Oberlin, Ohio 44074, United States
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47
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Evenbratt H, Nordstierna L, Ericson MB, Engström S. Cubic and sponge phases in ether lipid-solvent-water ternary systems: phase behavior and NMR characterization. Langmuir 2013; 29:13058-13065. [PMID: 24060205 DOI: 10.1021/la402732a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The phase behavior of 1-glyceryl monoleyl ether (GME) in mixtures of water and the solvents 1,5-pentanediol (POL) or N-methyl-2-pyrrolidone (NMP) was investigated by ocular inspection, polarization microscopy, and small-angle X-ray diffraction (SAXD). Phase diagrams were constructed based on analyses of more than 200 samples prepared using the two different solvents at 20 °C. The inverse hexagonal phase formed by GME in excess of water was transformed into the cubic and sponge phase with the increasing amount of each solvent. Particularly POL allowed for the formation of an extended sponge phase area in the phase diagram, comprising up to 70% POL-water mixture. The phase behavior using NMP was found to be similar to the earlier investigated solvent propylene glycol. The extended sponge phase for the POL system was attributed to POLs strong surface/interfacial activity with the potential to stabilize the polar/apolar interface of the sponge phase. The cubic and sponge phases formed using POL were further studied by NMR in order to measure the partitioning of POL between the lipid and aqueous domains of the phases. The domain partition coefficient K (lipid domain/aqueous domain) for POL in cubic and sponge phases was found to be 0.78 ± 0.14 and constant for the two phases.
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Affiliation(s)
- Hanne Evenbratt
- Department of Chemical and Biological Engineering, Pharmaceutical Technology, Chalmers University of Technology , SE-41296 Gothenburg, Sweden
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48
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Abstract
The instability of a polyisoprene (PI) thin film on a silicon substrate at room temperature in an aqueous environment was investigated by atomic force microscopy and optical microscopy. The instability mechanism changes from spinodal dewetting to hole nucleation with increasing film thickness, with the transitional thickness found to be around 46-50 nm. For PI films ≥50 nm, the dewetting was observed to proceed via successive stages of hole nucleation and growth, hole coalescence, cellular pattern formation and droplet formation. There is also a slowing down in the rate of the PI dewetting process and an increase in the pattern size as the film thickness is increased. In those films with observable holes, we also observed the coexistence of fine cellular cracking that is on a much smaller scale of hundreds of nanometres and extends only a few nanometres in depth from the film surface.
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Affiliation(s)
- Dan Liu
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
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49
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Worton DR, Surratt JD, Lafranchi BW, Chan AWH, Zhao Y, Weber RJ, Park JH, Gilman JB, de Gouw J, Park C, Schade G, Beaver M, Clair JMS, Crounse J, Wennberg P, Wolfe GM, Harrold S, Thornton JA, Farmer DK, Docherty KS, Cubison MJ, Jimenez JL, Frossard AA, Russell LM, Kristensen K, Glasius M, Mao J, Ren X, Brune W, Browne EC, Pusede SE, Cohen RC, Seinfeld JH, Goldstein AH. Observational insights into aerosol formation from isoprene. Environ Sci Technol 2013; 47:11403-11413. [PMID: 24004194 DOI: 10.1021/es4011064] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Atmospheric photooxidation of isoprene is an important source of secondary organic aerosol (SOA) and there is increasing evidence that anthropogenic oxidant emissions can enhance this SOA formation. In this work, we use ambient observations of organosulfates formed from isoprene epoxydiols (IEPOX) and methacrylic acid epoxide (MAE) and a broad suite of chemical measurements to investigate the relative importance of nitrogen oxide (NO/NO2) and hydroperoxyl (HO2) SOA formation pathways from isoprene at a forested site in California. In contrast to IEPOX, the calculated production rate of MAE was observed to be independent of temperature. This is the result of the very fast thermolysis of MPAN at high temperatures that affects the distribution of the MPAN reservoir (MPAN / MPA radical) reducing the fraction that can react with OH to form MAE and subsequently SOA (F(MAE formation)). The strong temperature dependence of F(MAE formation) helps to explain our observations of similar concentrations of IEPOX-derived organosulfates (IEPOX-OS; ~1 ng m(-3)) and MAE-derived organosulfates (MAE-OS; ~1 ng m(-3)) under cooler conditions (lower isoprene concentrations) and much higher IEPOX-OS (~20 ng m(-3)) relative to MAE-OS (<0.0005 ng m(-3)) at higher temperatures (higher isoprene concentrations). A kinetic model of IEPOX and MAE loss showed that MAE forms 10-100 times more ring-opening products than IEPOX and that both are strongly dependent on aerosol water content when aerosol pH is constant. However, the higher fraction of MAE ring opening products does not compensate for the lower MAE production under warmer conditions (higher isoprene concentrations) resulting in lower formation of MAE-derived products relative to IEPOX at the surface. In regions of high NOx, high isoprene emissions and strong vertical mixing the slower MPAN thermolysis rate aloft could increase the fraction of MPAN that forms MAE resulting in a vertically varying isoprene SOA source.
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Affiliation(s)
- David R Worton
- Department of Environmental Science, Policy and Management, ∥Department of Chemistry, University of California , Berkeley, California 94720, United States
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Pye HOT, Pinder RW, Piletic IR, Xie Y, Capps SL, Lin YH, Surratt JD, Zhang Z, Gold A, Luecken DJ, Hutzell WT, Jaoui M, Offenberg JH, Kleindienst TE, Lewandowski M, Edney EO. Epoxide pathways improve model predictions of isoprene markers and reveal key role of acidity in aerosol formation. Environ Sci Technol 2013; 47:11056-64. [PMID: 24024583 DOI: 10.1021/es402106h] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Isoprene significantly contributes to organic aerosol in the southeastern United States where biogenic hydrocarbons mix with anthropogenic emissions. In this work, the Community Multiscale Air Quality model is updated to predict isoprene aerosol from epoxides produced under both high- and low-NOx conditions. The new aqueous aerosol pathways allow for explicit predictions of two key isoprene-derived species, 2-methyltetrols and 2-methylglyceric acid, that are more consistent with observations than estimates based on semivolatile partitioning. The new mechanism represents a significant source of organic carbon in the lower 2 km of the atmosphere and captures the abundance of 2-methyltetrols relative to organosulfates during the simulation period. For the parametrization considered here, a 25% reduction in SOx emissions effectively reduces isoprene aerosol, while a similar reduction in NOx leads to small increases in isoprene aerosol.
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Affiliation(s)
- Havala O T Pye
- National Exposure Research Laboratory, US Environmental Protection Agency , Research Triangle Park, North Carolina, 27711 United States
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