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Li H, Peng T, Wang J, Zhang K, Wang D, Xie L. Probing the Interfacial Interaction Mechanisms of Nitrogen with Dodecane/Toluene: Implications for Foam Flooding. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024. [PMID: 39276096 DOI: 10.1021/acs.langmuir.4c02486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/16/2024]
Abstract
Interfacial interactions between deformable bubbles and oil drops have attracted much attention in foam flooding. However, interactions involving nitrogen bubbles have not been reported. In this work, the interaction forces between nitrogen and dodecane/toluene in aqueous solutions were quantified using the atomic force microscopy bubble probe technique. The effects of the solution pH, ionic type, and solution concentration on the interactions were analyzed. The van der Waals (vdW), electric double layer (EDL), and hydrophobic (HB) interactions were involved in the low-concentration solutions. The EDL repulsion in NaCl increased with solution pH, while in CaCl2 and MgCl2, the EDL repulsion in general decreased and then increased with pH, attributed to the adsorption of OH- and divalent cations and their hydration products. The adsorption of divalent cations at the toluene/water interface was pronounced by cation-π interactions. At pH 10, precipitated divalent cation hydroxides at the bubble/water and oil/water interfaces adsorbed more cations, causing the increase of the surface potential. At high salinity, the EDL interaction was suppressed and the vdW repulsion became predominant. The vdW force of nitrogen with toluene was stronger than that with dodecane. Under all of the solution conditions, the attractive interaction could not overcome the total repulsive interaction at the minimum separation, and thus no bubble attachment was observed, which implied that a stable bubble/liquid/oil film was essential for maintaining foam stability. This work provides useful insights into the interfacial interaction mechanisms in nitrogen foam flooding. The findings can be readily extended to other engineering systems such as oil flotation and bubble-oil-water emulsions.
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Affiliation(s)
- Han Li
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China
| | - Ting Peng
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China
| | - Jingyi Wang
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China
- Sichuan Provincial Key Laboratory of Oil and Gas Fields Applied Chemistry, Chengdu, Sichuan 610500, China
| | - Kuanjun Zhang
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China
| | - Dianlin Wang
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China
- Sichuan Provincial Key Laboratory of Oil and Gas Fields Applied Chemistry, Chengdu, Sichuan 610500, China
| | - Lei Xie
- School of Minerals Processing and Bioengineering, Central South University, Changsha, Hunan 410083, China
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2
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Sam S, Krem S, Lee J, Kim D. Recovery of Fatty Acid Monolayers by Salts Investigated by Sum-Frequency Generation Spectroscopy. J Phys Chem B 2022; 126:643-649. [PMID: 35026947 DOI: 10.1021/acs.jpcb.1c08028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Langmuir monolayers consisting of fatty acids with relatively short alkyl chains (C14H29COOH (pentadecanoic acid), C15H31COOH (palmitic acid), and C16H33COOH (heptadecanoic acid)) are stable at a neutral pH (pH ≈ 6) but become unstable at a high pH (pH ≈ 11). Further addition of a small amount of divalent salt in subphase water was found to recover the monolayer at a high pH because binding of the divalent cations to the carboxylic headgroups renders the molecule more stable against dissolution in subphase water. This revival of the monolayer was observed via a pressure-area isotherm measurement and sum-frequency generation spectrum in the CHx and OH ranges. Fatty acids with longer alkyl chains needed less amount of MgCl2 to recover the monolayer at a high pH. A much lower concentration of Mg2+ as compared to Ca2+ is required to revive fatty acid molecules to the surface. Monovalent and trivalent salts were compared with the above divalent salts on the ability to recover the fatty acid monolayers.
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Affiliation(s)
- Sokhuoy Sam
- Department of Physics, Sogang University, 35, Baekbeom-ro, Mapo-gu, Seoul 04107, Korea
| | - Sona Krem
- Department of Physics, Sogang University, 35, Baekbeom-ro, Mapo-gu, Seoul 04107, Korea
| | - Jaejin Lee
- Department of Physics, Sogang University, 35, Baekbeom-ro, Mapo-gu, Seoul 04107, Korea
| | - Doseok Kim
- Department of Physics, Sogang University, 35, Baekbeom-ro, Mapo-gu, Seoul 04107, Korea
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3
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Chen Z, Hu Y, He X, Xu Y, Liu X, Zhou Y, Hao L, Ruan Y. One-step fabrication of soft calcium superhydrophobic surfaces by a simple electrodeposition process. RSC Adv 2021; 12:297-308. [PMID: 35424497 PMCID: PMC8978675 DOI: 10.1039/d1ra06019h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/24/2021] [Indexed: 11/30/2022] Open
Abstract
A simple, one-step electrodeposition process was rapidly performed on a metal substrate to fabricate calcium superhydrophobic surfaces in an electrolyte containing calcium chloride (CaCl2), myristic acid (CH3(CH2)12COOH), and ethanol, which can avoid the intricate post-processing of surface treatment. The morphology and surface chemical compositions of the fabricated superhydrophobic surfaces were systematically examined by means of SEM, XRD, and FTIR, respectively. The results indicate that the deposited surfaces were mainly composed of calcium myristate, which can dramatically lower surface free energy. The shortest process for constructing a superhydrophobic surface is about 0.5 min, and the maximum contact angle of the as-prepared surfaces can reach as high as 166°, showing excellent superhydrophobicity. By adjusting the electrodeposition time, the structure of the cathodic surface transforms from the turfgrass structure, loose flower structures, larger and dense flower structures, secondary flower structures, and then into tertiary or more flower structures. The superhydrophobic surfaces showed excellent rebound performance with a high-speed camera. After a pressing force, their hardness increases, but the superhydrophobic performance is not weakened. Inversely, the bouncing performance is enhanced. This electrodeposition process offers a promising approach for large areas of superhydrophobic surfaces on conductive metals and strongly impacts the dynamics of water droplets. We investigated a one-step method for calcium superhydrophobic surface preparation and researched the formation process of loose, flower-like microstructures. Also, we found that the pressing force strongly impacts the dynamics of water droplets.![]()
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Affiliation(s)
- Zhi Chen
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
| | - Yongbo Hu
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
| | - Xu He
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
| | - Yihao Xu
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
| | - Xuesong Liu
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
| | - Yizhou Zhou
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
| | - Limei Hao
- Department of Applied Physics, School of Science, Xi'an University of Science & Technology Xi'an 710054 China
| | - Ying Ruan
- School of Physical Science and Technology, Northwestern Polytechnical University Xi'an 710129 China +86-29-88431664 +86-29-88431664
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4
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Marzonie M, Flores F, Sadoun N, Thomas MC, Valada-Mennuni A, Kaserzon S, Mueller JF, Negri AP. Toxicity thresholds of nine herbicides to coral symbionts (Symbiodiniaceae). Sci Rep 2021; 11:21636. [PMID: 34737333 PMCID: PMC8568975 DOI: 10.1038/s41598-021-00921-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/14/2021] [Indexed: 01/22/2023] Open
Abstract
Over 30 herbicides have been detected in catchments and waters of the Great Barrier Reef (GBR) and their toxicity to key tropical species, including the coral endosymbiotic algae Symbiodiniaceae, is not generally considered in current water quality guideline values (WQGVs). Mutualistic symbionts of the family Symbiodiniaceae are essential for the survival of scleractinian corals. We tested the effects of nine GBR-relevant herbicides on photosynthetic efficiency (ΔF/Fm′) and specific growth rate (SGR) over 14 days of cultured coral endosymbiont Cladocopium goreaui (formerly Symbiodinium clade C1). All seven Photosystem II (PSII) herbicides tested inhibited ΔF/Fm′ and SGR, with toxicity thresholds for SGR ranging between 2.75 and 320 µg L−1 (no effect concentration) and 2.54–257 µg L−1 (EC10). There was a strong correlation between EC50s for ΔF/Fm′ and SGR for all PSII herbicides indicating that inhibition of ΔF/Fm′ can be considered a biologically relevant toxicity endpoint for PSII herbicides to this species. The non-PSII herbicides haloxyfop and imazapic did not affect ΔF/Fm′ or SGR at the highest concentrations tested. The inclusion of this toxicity data for Symbiodiniaceae will contribute to improving WQGVs to adequately inform risk assessments and the management of herbicides in tropical marine ecosystems.
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Affiliation(s)
- Magena Marzonie
- Australian Institute of Marine Science, PMB No. 3, Townsville, QLD, 4810, Australia.,AIMS@JCU: Australian Institute of Marine Science and College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, 4811, Australia
| | - Florita Flores
- Australian Institute of Marine Science, PMB No. 3, Townsville, QLD, 4810, Australia. .,AIMS@JCU: Australian Institute of Marine Science and College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, 4811, Australia.
| | - Nora Sadoun
- Australian Institute of Marine Science, PMB No. 3, Townsville, QLD, 4810, Australia
| | - Marie C Thomas
- Australian Institute of Marine Science, PMB No. 3, Townsville, QLD, 4810, Australia
| | - Anais Valada-Mennuni
- Australian Institute of Marine Science, PMB No. 3, Townsville, QLD, 4810, Australia
| | - Sarit Kaserzon
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Andrew P Negri
- Australian Institute of Marine Science, PMB No. 3, Townsville, QLD, 4810, Australia.,AIMS@JCU: Australian Institute of Marine Science and College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, 4811, Australia
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5
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Carter-Fenk KA, Dommer AC, Fiamingo ME, Kim J, Amaro RE, Allen HC. Calcium bridging drives polysaccharide co-adsorption to a proxy sea surface microlayer. Phys Chem Chem Phys 2021; 23:16401-16416. [PMID: 34318808 DOI: 10.1039/d1cp01407b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Saccharides comprise a significant mass fraction of organic carbon in sea spray aerosol (SSA), but the mechanisms through which saccharides are transferred from seawater to the ocean surface and eventually into SSA are unclear. It is hypothesized that saccharides cooperatively adsorb to other insoluble organic matter at the air/sea interface, known as the sea surface microlayer (SSML). Using a combination of surface-sensitive infrared reflection-absorption spectroscopy and all-atom molecular dynamics simulations, we demonstrate that the marine-relevant, anionic polysaccharide alginate co-adsorbs to an insoluble palmitic acid monolayer via divalent cationic bridging interactions. Ca2+ induces the greatest extent of alginate co-adsorption to the monolayer, evidenced by the ∼30% increase in surface coverage, whereas Mg2+ only facilitates one-third the extent of co-adsorption at seawater-relevant cation concentrations due to its strong hydration propensity. Na+ cations alone do not facilitate alginate co-adsorption, and palmitic acid protonation hinders the formation of divalent cationic bridges between the palmitate and alginate carboxylate moieties. Alginate co-adsorption is largely confined to the interfacial region beneath the monolayer headgroups, so surface pressure, and thus monolayer surface coverage, only changes the amount of alginate co-adsorption by less than 5%. Our results provide physical and molecular characterization of a potentially significant polysaccharide enrichment mechanism within the SSML.
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Affiliation(s)
- Kimberly A Carter-Fenk
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
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6
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Luo X, Lin Q, Wen S, Wang Y, Lai H, Qi L, Wu X, Zhou Y, Song Z. Effect of Sodium Dodecyl Sulfonate on the Foam Stability and Adsorption Configuration of Dodecylamine at the Gas-Liquid Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1235-1246. [PMID: 33434429 DOI: 10.1021/acs.langmuir.0c03248] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this study, the effect of sodium dodecyl sulfonate (SDS) on the foam stability of dodecylamine (DDA) and on its adsorption configuration at the gas-liquid interface was investigated. Froth stability experiments, surface tension measurements, time-of-flight secondary-ion mass spectrometry measurements, and molecular dynamics simulation calculations were performed in this investigation. The results revealed that the foam stability of DDA solution was extremely strong, and the addition of SDS could decrease the foam stability when the concentration of DDA was less than a certain value. The decrease in foam stability could be ascribed to several reasons, namely, the big cross-sectional area of SDS at the gas-liquid interface and low adsorption capacity of surfactants at the gas-liquid interface, the high surface tension, the change in the double-layer structure, the small thickness of the gas-liquid interfacial layer, the weak interaction intensity between the head groups of the surfactants and the water molecules, the strong movement ability of the water molecules around the head groups, and the sparse and less upright arrangement configuration of molecules at the gas-liquid interface. These findings can greatly help in solving the strong foam stability problem in DDA flotation and provide a method for reducing foam stability.
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Affiliation(s)
- Ximei Luo
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China
| | - Qiqiang Lin
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
| | - Shuming Wen
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China
| | - Yunfan Wang
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China
- Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China
| | - Hao Lai
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
| | - Linping Qi
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
| | - Xuetong Wu
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
| | - Yongfeng Zhou
- Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
| | - Zhenguo Song
- State Key Laboratory of Mineral Processing Science and Technology, BGRIMM Technology Group, Beijing 100160, China
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7
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Thomas MC, Flores F, Kaserzon S, Reeks TA, Negri AP. Toxicity of the herbicides diuron, propazine, tebuthiuron, and haloxyfop to the diatom Chaetoceros muelleri. Sci Rep 2020; 10:19592. [PMID: 33177549 PMCID: PMC7658992 DOI: 10.1038/s41598-020-76363-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 10/23/2020] [Indexed: 01/16/2023] Open
Abstract
Conventional photosystem II (PSII) herbicides applied in agriculture can pose significant environmental risks to aquatic environments. In response to the frequent detection of these herbicides in the Great Barrier Reef (GBR) catchment area, transitions towards 'alternative' herbicides are now widely supported. However, water quality guideline values (WQGVs) for alternative herbicides are lacking and their potential ecological impacts on tropical marine species are generally unknown. To improve our understanding of the risks posed by some of these alternative herbicides on marine species under tropical conditions, we tested the effects of four herbicides on the widely distributed diatom Chaetoceros muelleri. The PSII herbicides diuron, propazine, and tebuthiuron induced substantial reductions in both 24 h effective quantum yields (ΔF/Fm') and 3-day specific growth rates (SGR). The effect concentrations, which reduced ΔF/Fm' by 50% (EC50), ranged from 4.25 µg L-1 diuron to 48.6 µg L-1 propazine, while the EC50s for SGR were on average threefold higher, ranging from 12.4 µg L-1 diuron to 187 µg L-1 tebuthiuron. Our results clearly demonstrated that inhibition of ΔF/Fm' in PSII is directly linked to reduced growth (R2 = 0.95) in this species, further supporting application of ΔF/Fm' inhibition as a valid bioindicator of ecological relevance for PSII herbicides that could contribute to deriving future WQGVs. In contrast, SGR and ΔF/Fm' of C. muelleri were nonresponsive to the non-PSII herbicide haloxyfop at the highest concentration tested (4570 µg L-1), suggesting haloxyfop does not pose a risk to C. muelleri. The toxicity thresholds (e.g. no effect concentrations; NECs) identified in this study will contribute to the derivation of high-reliability marine WQGVs for some alternative herbicides detected in GBR waters and support future assessments of the cumulative risks of complex herbicide mixtures commonly detected in coastal waters.
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Affiliation(s)
- Marie C Thomas
- Australian Institute of Marine Science, Townsville, QLD, 4810, Australia.
| | - Florita Flores
- Australian Institute of Marine Science, Townsville, QLD, 4810, Australia
| | - Sarit Kaserzon
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Timothy A Reeks
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Andrew P Negri
- Australian Institute of Marine Science, Townsville, QLD, 4810, Australia
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8
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Bai S, Kubelka J, Piri M. A positively charged calcite surface model for molecular dynamics studies of wettability alteration. J Colloid Interface Sci 2020; 569:128-139. [PMID: 32105900 DOI: 10.1016/j.jcis.2020.02.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 02/06/2020] [Accepted: 02/11/2020] [Indexed: 11/29/2022]
Abstract
A new model for a positively charged calcite surface was developed to allow realistic molecular dynamics studies of wettability alteration on carbonate rocks. The surface charge was introduced in a manner consistent with the underlying calcite geochemistry and with the conclusions of recent quantum mechanical studies. The simulations using the new surface model demonstrate that the experimentally observed wettability behavior of calcite is represented correctly. In particular, the model surface became oil-wet due to the adsorption of the carboxylate species. Furthermore, the oil-wet conditions were reversed more effectively by a cationic surfactant than by an anionic one, in agreement with the majority of experimental observations. Finally, with simulated smart water, the well-documented wettability alteration abilities of Ca2+ and SO42- could be explained by the formation of ion-pairs and competitive adsorption onto the surface, respectively. The simulation results with the new surface model conceptually agree with the electric double layer expansion being the predominant mechanism for the low salinity effect in oil recovery enhancement. The proposed calcite surface model will benefit future simulation studies on the wettability characteristics of carbonate rocks, and facilitate the design and optimizations of chemical agents and formulations to enhance the oil recovery from carbonate reservoirs.
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Affiliation(s)
- Shixun Bai
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, WY 82071, United States
| | - Jan Kubelka
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, WY 82071, United States.
| | - Mohammad Piri
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, WY 82071, United States
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9
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Luo M, Shemesh D, Sullivan MN, Alves MR, Song M, Gerber RB, Grassian VH. Impact of pH and NaCl and CaCl2 Salts on the Speciation and Photochemistry of Pyruvic Acid in the Aqueous Phase. J Phys Chem A 2020; 124:5071-5080. [DOI: 10.1021/acs.jpca.0c01016] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Man Luo
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - Dorit Shemesh
- Institute of Chemistry and Fritz Haber Research Center, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Michael N. Sullivan
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - Michael R. Alves
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - Meishi Song
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - R. Benny Gerber
- Institute of Chemistry and Fritz Haber Research Center, Hebrew University of Jerusalem, Jerusalem 91904, Israel
- Department of Chemistry, University of California, Irvine, California 92617, United States
| | - Vicki H. Grassian
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
- Scripps Institution of Oceanography, University of California, San Diego, California 92037, United States
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10
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Thomas MC, Flores F, Kaserzon S, Fisher R, Negri AP. Toxicity of ten herbicides to the tropical marine microalgae Rhodomonas salina. Sci Rep 2020; 10:7612. [PMID: 32376837 PMCID: PMC7203118 DOI: 10.1038/s41598-020-64116-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/06/2020] [Indexed: 11/09/2022] Open
Abstract
Herbicide contamination of nearshore tropical marine ecosystems is widespread and persistent; however, risks posed by most ‘alternative’ herbicides to tropical marine microalgae remain poorly understood. Experimental exposures of the important but understudied microalgae Rhodomonas salina to seven individual Photosystem II (PSII) inhibitor herbicides (diuron, metribuzin, hexazinone, tebuthiuron, bromacil, simazine, propazine) led to inhibition of effective quantum yield (ΔF/Fm′) and subsequent reductions in specific growth rates (SGR). The concentrations which reduced ΔF/Fm′ by 50% (EC50) ranged from 1.71-59.2 µg L−1, while the EC50s for SGR were 4-times higher, ranging from 6.27-188 µg L−1. Inhibition of ΔF/Fm′ indicated reduced photosynthetic capacity, and this correlated linearly with reduced SGR (R2 = 0.89), supporting the application of ∆F/Fm’ inhibition as a robust and sensitive indicator of sub-lethal toxicity of PSII inhibitors for this microalga. The three non-PSII inhibitor herbicides (imazapic, haloxyfop and 2,4-Dichlorophenoxyacetic acid (2,4-D)) caused low or no toxic responses to the function of the PSII or growth at the highest concentrations tested suggesting these herbicides pose little risk to R. salina. This study highlights the suitability of including R. salina in future species sensitivity distributions (SSDs) to support water quality guideline development for the management of herbicide contamination in tropical marine ecosystems.
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Affiliation(s)
- Marie C Thomas
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia. .,AIMS@JCU: Australian Institute of Marine Science, College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, 4811, Australia.
| | - Florita Flores
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia.,AIMS@JCU: Australian Institute of Marine Science, College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, 4811, Australia
| | - Sarit Kaserzon
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Rebecca Fisher
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, University of Western Australia, Crawley, WA, 6009, Australia
| | - Andrew P Negri
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia.,AIMS@JCU: Australian Institute of Marine Science, College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, 4811, Australia
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11
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Unger I, Saak CM, Salter M, Zieger P, Patanen M, Björneholm O. Influence of Organic Acids on the Surface Composition of Sea Spray Aerosol. J Phys Chem A 2020; 124:422-429. [PMID: 31833771 DOI: 10.1021/acs.jpca.9b09710] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Recent studies on sea spray aerosol indicate an enrichment of Ca2+ in small particles, which are often thought to originate from the very surface of a water body when bubbles burst. One model to explain this observation is the formation of ion pairs between Ca2+(aq) and surface-active organic species. In this study, we have used X-ray photoelectron spectroscopy to probe aqueous salt solutions and artificial sea spray aerosol to study whether ion pairing in the liquid environment also affects the surface composition of dry aerosol. Carboxylic acids were added to the sample solutions to mimic some of the organic compounds present in natural seawater. Our results show that the formation of a core-shell structure governs the surface composition of the aerosol. The core-shell structure contrasts previous observations of the dry sea spray aerosol on substrates. As such, this may indicate that substrates can impact the morphology of the dried aerosol.
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Affiliation(s)
- Isaak Unger
- Uppsala University , Box 516, SE-75120 Uppsala , Sweden
| | | | - Matthew Salter
- Uppsala University , Box 516, SE-75120 Uppsala , Sweden.,Department of Environmental Science and Analytical Chemistry , Stockholm University , SE-10691 Stockholm , Sweden.,Bolin Centre for Climate Research , SE-10691 Stockholm , Sweden
| | - Paul Zieger
- Department of Environmental Science and Analytical Chemistry , Stockholm University , SE-10691 Stockholm , Sweden.,Bolin Centre for Climate Research , SE-10691 Stockholm , Sweden
| | - Minna Patanen
- Nano and Molecular Systems Research Unit, Faculty of Science , University of Oulu , P.O. Box 8000 FI-90570 Oulu , Finland
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12
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Richert ME, Gochev GG, Braunschweig B. Specific Ion Effects of Trivalent Cations on the Structure and Charging State of β-Lactoglobulin Adsorption Layers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:11299-11307. [PMID: 31398284 DOI: 10.1021/acs.langmuir.9b01803] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The properties of proteins at interfaces are important to many processes as well as in soft matter materials such as aqueous foam. Particularly, the protein interfacial behavior is strongly linked to different factors like the solution pH or the presence of electrolytes. Here, the nature of the electrolyte ions can significantly modify the interfacial properties of proteins. Therefore, molecular level studies on interfacial structures and charging states are needed. In this work, we addressed the effects of Y3+ and Nd3+ cations on the adsorption of the whey protein β-lactoglobulin (BLG) at air-water interfaces as the function of electrolyte concentration. Both cations caused very similar but dramatic changes at the interface and in the bulk solution. Here, measurements of the electrophoretic mobility and with vibrational sum-frequency generation (SFG) spectroscopy were applied and consistently showed a reversal of the BLG net charge at remarkably low ion concentrations of 30 (bulk) and 40 (interface) μM of Y3+ or Nd3+ for a BLG concentration of 15 μM. SFG spectra of carboxylate stretching vibrations from Asp or Glu residues of interfacial BLG showed significant changes in the resonance frequency, which we associate to specific and efficient binding of Y3+ or Nd3+ ions to the proteins carboxylate groups. Characteristic reentrant condensation for BLG moieties with bound trivalent ions was found in a broad concentration range around the point of zero net charge. The highest colloidal stability of BLG was found for ion concentrations <20 μM and >50 μM. Investigations on macroscopic foams from BLG solutions revealed the existence of structure-property relations between the interfacial charging state and the foam stability. In fact, a minimum in foam stability at 20 μM ion concentration was found when the interfacial net charge was negligible. At this concentration, we propose that the persistent BLG molecules and weakly charged BLG aggregates drive foam stability, while outside the bulk reentrant zone the electrostatic disjoining pressure inside foam lamellae dominates foam stability. Our results provide new information on the charge reversal at the liquid-gas interface of protein/ion dispersions. Therefore, we see our findings as an important step in the clarification of reentrant condensation effects at interfaces and their relevance to foam stability.
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Affiliation(s)
- Manuela E Richert
- Institute of Physical Chemistry and Center for Soft Nanoscience , Westfälische Wilhelms-Universität Münster Corrensstraße 28/30 , 48149 Münster , Germany
| | - Georgi G Gochev
- Institute of Physical Chemistry and Center for Soft Nanoscience , Westfälische Wilhelms-Universität Münster Corrensstraße 28/30 , 48149 Münster , Germany
| | - Björn Braunschweig
- Institute of Physical Chemistry and Center for Soft Nanoscience , Westfälische Wilhelms-Universität Münster Corrensstraße 28/30 , 48149 Münster , Germany
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13
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Denton JK, Kelleher PJ, Johnson MA, Baer MD, Kathmann SM, Mundy CJ, Wellen Rudd BA, Allen HC, Choi TH, Jordan KD. Molecular-level origin of the carboxylate head group response to divalent metal ion complexation at the air-water interface. Proc Natl Acad Sci U S A 2019; 116:14874-14880. [PMID: 31278149 PMCID: PMC6660762 DOI: 10.1073/pnas.1818600116] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We exploit gas-phase cluster ion techniques to provide insight into the local interactions underlying divalent metal ion-driven changes in the spectra of carboxylic acids at the air-water interface. This information clarifies the experimental findings that the CO stretching bands of long-chain acids appear at very similar energies when the head group is deprotonated by high subphase pH or exposed to relatively high concentrations of Ca2+ metal ions. To this end, we report the evolution of the vibrational spectra of size-selected [Ca2+·RCO2-]+·(H2O) n=0to12 and RCO2-·(H2O) n=0to14 cluster ions toward the features observed at the air-water interface. Surprisingly, not only does stepwise hydration of the RCO2- anion and the [Ca2+·RCO2-]+ contact ion pair yield solvatochromic responses in opposite directions, but in both cases, the responses of the 2 (symmetric and asymmetric stretching) CO bands to hydration are opposite to each other. The result is that both CO bands evolve toward their interfacial asymptotes from opposite directions. Simulations of the [Ca2+·RCO2-]+·(H2O) n clusters indicate that the metal ion remains directly bound to the head group in a contact ion pair motif as the asymmetric CO stretch converges at the interfacial value by n = 12. This establishes that direct metal complexation or deprotonation can account for the interfacial behavior. We discuss these effects in the context of a model that invokes the water network-dependent local electric field along the C-C bond that connects the head group to the hydrocarbon tail as the key microscopic parameter that is correlated with the observed trends.
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Affiliation(s)
- Joanna K Denton
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520
| | | | - Mark A Johnson
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520;
| | - Marcel D Baer
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352
| | - Shawn M Kathmann
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352
| | - Christopher J Mundy
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352
- Department of Chemical Engineering, University of Washington, Seattle, WA 98195
| | - Bethany A Wellen Rudd
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210
- Department of Chemistry, Ohio Wesleyan University, Delaware, OH 43015
| | - Heather C Allen
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Tae Hoon Choi
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260
| | - Kenneth D Jordan
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15260
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14
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Sthoer A, Hladílková J, Lund M, Tyrode E. Molecular insight into carboxylic acid-alkali metal cations interactions: reversed affinities and ion-pair formation revealed by non-linear optics and simulations. Phys Chem Chem Phys 2019; 21:11329-11344. [PMID: 31107479 DOI: 10.1039/c9cp00398c] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Specific interactions between the carboxylic acid moiety and the monovalent salts CsCl, NaCl, and LiCl, have been investigated in Langmuir monolayers using vibrational sum frequency spectroscopy (VSFS) and complemented with coarse grained and all-atom molecular dynamics simulations. By exploiting VSFS's intrinsic surface specificity, an emphasis was made on targeting headgroup vibrations of both its charged and uncharged forms as well as water molecules in the interfacial layer. The degree of deprotonation of the monolayer as a function of cation concentration and pH was experimentally determined and theoretically rationalized. Starting from 100 mM, the surface charge was overestimated by the Gouy-Chapman model and varied depending on the identity of the cation, highlighting the appearance of ion specific effects. Agreement could be found using a modified Poisson-Boltzmann model that takes into account steric effects, with a fitted effective ion-size compatible with the hydrated ion diameters. The relative affinity of the cations to the carboxylic acid moiety was pH dependent: at pH 4.5 they arranged in the order Cs+ > Na+ > Li+, but fully reversed (Li+ > Na+ > Cs+) at pH 9. Simulations yielded microscopic insight into the origin of this behavior, with the cations showing contrasting interaction preferences for either the uncharged carboxylic acid or the charged carboxylate. Sum frequency spectra also provided evidence that all cations remained hydrated when interacting with the charged headgroup, forming solvent-separated or solvent-shared ion pairs. However, for the specific case of 1 M Li+ at pH 9, contact ion pairs were formed. Finally, the remarkable effect of trace metal multivalent cations in the interpretation of experiments is briefly discussed. The results provide exciting new insights into the complex interactions of alkali metal cations with the biophysically relevant carboxylic acid moiety.
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Affiliation(s)
- Adrien Sthoer
- Department of Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.
| | - Jana Hladílková
- Division of Theoretical Chemistry, Lund University, P.O.B. 124, SE-22100 Lund, Sweden
| | - Mikael Lund
- Division of Theoretical Chemistry, Lund University, P.O.B. 124, SE-22100 Lund, Sweden
| | - Eric Tyrode
- Department of Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.
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15
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Li S, Du L, Zhang Q, Wang W. Stabilizing mixed fatty acid and phthalate ester monolayer on artificial seawater. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:626-633. [PMID: 30014940 DOI: 10.1016/j.envpol.2018.07.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Phthalate esters which are widely used as industrial chemicals have become widespread contaminants in the marine environment. However, little information is available on the interfacial behavior of phthalate esters in the seawater, where contaminants generally occur at elevated concentrations and have the potential to transfer into the atmosphere through wave breaking on sea surface. We used artificial seawater coated with fatty acids to simulate sea surface microlayer in a Langmuir trough. The interactions of saturated fatty acids (stearic acid (SA) and palmitic acid (PA)) with one of the most abundant phthalate esters (di-(2-ethylhexyl) phthalate (DEHP)), were investigated under artificial seawater and pure water conditions. Pure DEHP monolayer was not stable, while more stable mixed monolayers were formed by SA and DEHP on the artificial seawater at relatively low surface pressure. Sea salts in the subphase can lower the excess Gibbs free energy to form more stable mixed monolayer. Among the ten components in the sea salts, Ca2+ ions played the major role in condensation of mixed monolayer. The condensed characteristic of the mixed SA (or PA)/DEHP monolayers suggested that the hydrocarbon chains were ordered on artificial seawater. By means of infrared reflection-absorption spectroscopy (IRRAS), we found that multiple sea salt mixtures induced deprotonated forms of fatty acids at the air-water interface. Sea salts can improve the stability and lifetime of mixed fatty acid and phthalate ester monolayer on aqueous droplets in the atmosphere. Interfacial properties of mixed fatty acid and phthalate ester monolayers at the air-ocean interface are important to help understand their behavior and fate in the marine environment.
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Affiliation(s)
- Siyang Li
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Lin Du
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China.
| | - Qingzhu Zhang
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Wenxing Wang
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
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16
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Metal Ion Interactions with Crude Oil Components: Specificity of Ca2+ Binding to Naphthenic Acid at an Oil/Water Interface. COLLOIDS AND INTERFACES 2018. [DOI: 10.3390/colloids2030040] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
On the basis of dynamic interfacial tension measurements, Ca2+ has been shown specifically to interact with naphthenic acid (NA) at the n-heptane/water interface, consistent with NA adsorption followed by interfacial complexation and formation of a more ordered interfacial film. Optimum concentrations of Ca2+ and NA have been found to yield lower, time-dependent interfacial tensions, not evident for Mg2+ and Sr2+ or for several alkali metal ions studied. The results reflect the specific hydration and coordination chemistry of Ca2+ seen in biology. Owing to the ubiquitous presence of Ca2+ in oilfield waters, this finding has potential relevance to the surface chemistry underlying crude oil recovery. For example, “locking” acidic components at water/oil interfaces may be important for crude oil emulsion stability, or in bonding bulk oil to mineral surfaces through an aqueous phase, potentially relevant for carbonate reservoirs. The relevance of the present results to low salinity waterflooding as an enhanced crude oil recovery technique is also discussed.
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17
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Reddy SK, Thiraux R, Wellen Rudd BA, Lin L, Adel T, Joutsuka T, Geiger FM, Allen HC, Morita A, Paesani F. Bulk Contributions Modulate the Sum-Frequency Generation Spectra of Water on Model Sea-Spray Aerosols. Chem 2018. [DOI: 10.1016/j.chempr.2018.04.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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18
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Wellen Rudd BA, Vidalis AS, Allen HC. Thermodynamic versus non-equilibrium stability of palmitic acid monolayers in calcium-enriched sea spray aerosol proxy systems. Phys Chem Chem Phys 2018; 20:16320-16332. [DOI: 10.1039/c8cp01188e] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Calcium ions bind to palmitic acid monolayers at the air–aqueous interface resulting in changes of both thermodynamic and non-equilibrium stability.
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Affiliation(s)
| | - Andrew S. Vidalis
- Department of Chemistry & Biochemistry
- The Ohio State University
- Columbus
- USA
| | - Heather C. Allen
- Department of Chemistry & Biochemistry
- The Ohio State University
- Columbus
- USA
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19
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DePalma JW, Kelleher PJ, Tavares LC, Johnson MA. Coordination-Dependent Spectroscopic Signatures of Divalent Metal Ion Binding to Carboxylate Head Groups: H 2- and He-Tagged Vibrational Spectra of M 2+·RCO 2¯ (M = Mg and Ca, R = -CD 3, -CD 2CD 3) Complexes. J Phys Chem Lett 2017; 8:484-488. [PMID: 28060510 DOI: 10.1021/acs.jpclett.6b02964] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We explore the intramolecular distortions present in divalent metal ion-carboxylate ion pairs using vibrational spectroscopy of the cryogenically cooled, mass-selected species isolated in the gas phase. The spectral signatures of the C-O stretching modes are identified using the perdeutero isotopologues of the acetate and propionate anions to avoid congestion arising from the CH2 fundamentals. Both Ca2+ and Mg2+ are observed to bind in a symmetrical, so-called "bidentate" arrangement to the -CO2¯ group. The very strong deformations of the head groups displayed by the binary complexes dramatically relax when either neutral water molecules or counterions are attached to the Mg2+RCO2¯ cation. These results emphasize the critical role that local coordination plays when using the RCO2¯ bands to deduce the metal ion complexation motif in condensed media.
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Affiliation(s)
- Joseph W DePalma
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University , 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Patrick J Kelleher
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University , 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Laís C Tavares
- Instituto de Química, Universidade de São Paulo , Caixa Postal 26077, São Paulo, CEP 05508-900, Brazil
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University , 225 Prospect Street, New Haven, Connecticut 06520, United States
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20
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Ganesan SJ, Xu H, Matysiak S. Influence of Monovalent Cation Size on Nanodomain Formation in Anionic–Zwitterionic Mixed Bilayers. J Phys Chem B 2017; 121:787-799. [DOI: 10.1021/acs.jpcb.6b10099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sai J. Ganesan
- Fischell
Department of Bioengineering and ‡Biophysics Program, Institute of
Physical Science and Technology, University of Maryland, College
Park, Maryland 20742, United States
| | - Hongcheng Xu
- Fischell
Department of Bioengineering and ‡Biophysics Program, Institute of
Physical Science and Technology, University of Maryland, College
Park, Maryland 20742, United States
| | - Silvina Matysiak
- Fischell
Department of Bioengineering and ‡Biophysics Program, Institute of
Physical Science and Technology, University of Maryland, College
Park, Maryland 20742, United States
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21
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Enami S, Fujii T, Sakamoto Y, Hama T, Kajii Y. Carboxylate Ion Availability at the Air–Water Interface. J Phys Chem A 2016; 120:9224-9234. [DOI: 10.1021/acs.jpca.6b08868] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shinichi Enami
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan
| | - Tomihide Fujii
- Graduate School of Global Environmental
Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Yosuke Sakamoto
- Graduate School of Global Environmental
Studies, Kyoto University, Kyoto 606-8501, Japan
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8316, Japan
| | - Tetsuya Hama
- Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan
| | - Yoshizumi Kajii
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan
- Graduate School of Global Environmental
Studies, Kyoto University, Kyoto 606-8501, Japan
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8316, Japan
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22
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Zhang T, Cathcart MG, Vidalis AS, Allen HC. Cation effects on phosphatidic acid monolayers at various pH conditions. Chem Phys Lipids 2016; 200:24-31. [DOI: 10.1016/j.chemphyslip.2016.06.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 05/11/2016] [Accepted: 06/01/2016] [Indexed: 11/29/2022]
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23
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Balzerowski P, Meister K, Versluis J, Bakker HJ. Heterodyne-detected sum frequency generation spectroscopy of polyacrylic acid at the air/water-interface. Phys Chem Chem Phys 2016; 18:2481-7. [DOI: 10.1039/c5cp06177f] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A complete picture of the surface affinity and structure of polyacrylic acid at the air–water interface was determined.
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Affiliation(s)
| | - Konrad Meister
- FOM-Institute for Atomic and Molecular Physics AMOLF
- 1098XG Amsterdam
- The Netherlands
| | - Jan Versluis
- FOM-Institute for Atomic and Molecular Physics AMOLF
- 1098XG Amsterdam
- The Netherlands
| | - Huib J. Bakker
- FOM-Institute for Atomic and Molecular Physics AMOLF
- 1098XG Amsterdam
- The Netherlands
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24
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Hua W, Verreault D, Allen HC. Solvation of Calcium-Phosphate Headgroup Complexes at the DPPC/Aqueous Interface. Chemphyschem 2015; 16:3910-5. [PMID: 26486616 DOI: 10.1002/cphc.201500720] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Wei Hua
- Department of Chemistry & Biochemistry; The Ohio State University; 100 West 18th Avenue Columbus OH 43210 USA
| | - Dominique Verreault
- Department of Chemistry & Biochemistry; The Ohio State University; 100 West 18th Avenue Columbus OH 43210 USA
| | - Heather C. Allen
- Department of Chemistry & Biochemistry; The Ohio State University; 100 West 18th Avenue Columbus OH 43210 USA
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25
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Champagne AM, Allen HC, Williams JB. Lipid composition and molecular interactions change with depth in the avian stratum corneum to regulate cutaneous water loss. ACTA ACUST UNITED AC 2015; 218:3032-41. [PMID: 26447196 DOI: 10.1242/jeb.125310] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The outermost 10-20 µm of the epidermis, the stratum corneum (SC), consists of flat, dead cells embedded in a matrix of intercellular lipids. These lipids regulate cutaneous water loss (CWL), which accounts for over half of total water loss in birds. However, the mechanisms by which lipids are able to regulate CWL and how these mechanisms change with depth in the SC are poorly understood. We used attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) to measure lipid-lipid and lipid-water interactions as a function of depth in the SC of house sparrows (Passer domesticus Linnaeus) in the winter and summer. We then compared these molecular interactions at each depth with lipid composition at the same depth. We found that in both groups, water content increased with depth in the SC, and likely contributed to greater numbers of gauche defects in lipids in deeper levels of the SC. In winter-caught birds, which had lower rates of CWL than summer-caught birds, water exhibited stronger hydrogen bonding in deeper layers of the SC, and these strong hydrogen bonds were associated with greater amounts of polar lipids such as ceramides and cerebrosides. Based on these data, we propose a model by which polar lipids in deep levels of the SC form strong hydrogen bonds with water molecules to increase the viscosity of water and slow the permeation of water through the SC.
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Affiliation(s)
- Alex M Champagne
- Department of Biology, University of Southern Indiana, Science Center 1255 8600 University Blvd, Evansville, IN 47712, USA
| | - Heather C Allen
- Department of Chemistry and Biochemistry, The Ohio State University, 1102 Newman and Wolfrom Laboratory, 100 W 18th Avenue, Columbus, OH 43210, USA Department of Pathology, The Ohio State University, 129 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA
| | - Joseph B Williams
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Aronoff Laboratory, 318 W 12th Avenue, Columbus, OH 43210, USA
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26
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Mechanistic study of wettability alteration of oil-wet calcite: The effect of magnesium ions in the presence and absence of cationic surfactant. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.07.001] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Wu L, Liao L, Lv G. Influence of interlayer cations on organic intercalation of montmorillonite. J Colloid Interface Sci 2015; 454:1-7. [PMID: 26001131 DOI: 10.1016/j.jcis.2015.04.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 04/09/2015] [Accepted: 04/12/2015] [Indexed: 10/23/2022]
Abstract
The influence of the types of interlayer cations on organic intercalation of montmorillonite (Mt) was studied in this paper. The distribution of Na(+), K(+), Mg(2+), Ca(2+) and Fe(3+) in montmorillonite interlayer, their interaction with structure layers and the effect of interlayer cations on the basal spacing of Mt, the amount of binding water for different interlayer cations and the binding force between them were investigated systematically. 1-Hexadecy1-3-methylimidazolium chloride monohydrate (C16mimCl) was intercalated into montmorillonites with different interlayer cations. The influence of interlayer cations on organic intercalation was investigated. Molecular dynamics (MD) modeling was used to speculate the interlayer microstructures of the organically intercalated Mt with different interlayer cations. These simulations help to predict the microstructure of organo-Mt and guide their relevant engineering applications.
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Affiliation(s)
- Limei Wu
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China
| | - Libing Liao
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China.
| | - Guocheng Lv
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China.
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28
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Ait-Akbour R, Boustingorry P, Leroux F, Leising F, Taviot-Guého C. Adsorption of PolyCarboxylate Poly(ethylene glycol) (PCP) esters on Montmorillonite (Mmt): Effect of exchangeable cations (Na+, Mg2+ and Ca2+) and PCP molecular structure. J Colloid Interface Sci 2015; 437:227-234. [DOI: 10.1016/j.jcis.2014.09.027] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 09/04/2014] [Accepted: 09/08/2014] [Indexed: 10/24/2022]
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29
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Sobanska S, Barbillat J, Moreau M, Nuns N, De Waele I, Petitprez D, Tobon Y, Brémard C. Influence of stearic acid coating of the NaCl surface on the reactivity with NO2 under humidity. Phys Chem Chem Phys 2015; 17:10963-77. [DOI: 10.1039/c4cp05655h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the atmosphere, sea salt aerosols, containing mainly NaCl, can accumulate fatty acids on surface and undergo spatially heterogeneous chemistry with atmospheric nitrogen oxides.
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Affiliation(s)
- S. Sobanska
- Laboratoire de Spectrochimie Infrarouge et Raman (LASIR)
- UMR CNRS 8516
- Université de Lille Science et Technologie
- 59655 Villeneuve d'Ascq Cedex
- France
| | - J. Barbillat
- Laboratoire de Spectrochimie Infrarouge et Raman (LASIR)
- UMR CNRS 8516
- Université de Lille Science et Technologie
- 59655 Villeneuve d'Ascq Cedex
- France
| | - M. Moreau
- Laboratoire de Spectrochimie Infrarouge et Raman (LASIR)
- UMR CNRS 8516
- Université de Lille Science et Technologie
- 59655 Villeneuve d'Ascq Cedex
- France
| | - N. Nuns
- Institut des Molécules et de la Matière Condensée de Lille
- IMMCL Chevreul
- 59655 Villeneuve d'Ascq Cedex
- France
| | - I. De Waele
- Laboratoire de Spectrochimie Infrarouge et Raman (LASIR)
- UMR CNRS 8516
- Université de Lille Science et Technologie
- 59655 Villeneuve d'Ascq Cedex
- France
| | - D. Petitprez
- Laboratoire de PhysicoChimie des Processus de Combustion et de l'Atmosphère (PC2A)
- UMR CNRS 8522
- Université de Lille
- Sciences et Technologie
- Bât C11
| | - Y. Tobon
- Laboratoire de Spectrochimie Infrarouge et Raman (LASIR)
- UMR CNRS 8516
- Université de Lille Science et Technologie
- 59655 Villeneuve d'Ascq Cedex
- France
| | - C. Brémard
- Laboratoire de Spectrochimie Infrarouge et Raman (LASIR)
- UMR CNRS 8516
- Université de Lille Science et Technologie
- 59655 Villeneuve d'Ascq Cedex
- France
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Aggregation of inkjet ink components by Ca and Mg ions in relation to colorant pigment distribution in paper. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.05.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Robertson EJ, Beaman DK, Richmond GL. Designated drivers: the differing roles of divalent metal ions in surfactant adsorption at the oil-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:15511-15520. [PMID: 24266707 DOI: 10.1021/la403665n] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Divalent metal ions play numerous roles in biological, technological, and environmental systems. This study examines the role of a variety of ions, Mg(2+), Ca(2+), Mn(2+), Ni(2+), Cu(2+), and Zn(2+), in the adsorption of sodium decanoate at the carbon tetrachloride-water interface. For all ions studied, the ions drive the adsorption of the surfactant to the interface. Using vibrational sum-frequency spectroscopy and the carboxylic acid vibrational modes as a signature for metal ion binding, each metal salt is found to play a distinctly different role in the molecular characteristics of surfactant adsorption at the interface. Additional spectroscopic studies of the methyl and methylene vibrations are monitored to track the ordering of the alkyl chains when metal salts are added to solution. How the metal-surfactant binding impacts the surfactant structure, orientation, and solvation is explored. How these spectroscopic measurements compare with the degree of adsorption as measured by interfacial tension data is presented.
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Affiliation(s)
- Ellen J Robertson
- Department of Chemistry, University of Oregon , Eugene, Oregon 97403, United States
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Plath KL, Valley NA, Richmond GL. Ion-Induced Reorientation and Distribution of Pentanone in the Air–Water Boundary Layer. J Phys Chem A 2013; 117:11514-27. [DOI: 10.1021/jp408188x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Kathryn L. Plath
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - Nicholas A. Valley
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403, United States
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Palmitic Acid on Salt Subphases and in Mixed Monolayers of Cerebrosides: Application to Atmospheric Aerosol Chemistry. ATMOSPHERE 2013. [DOI: 10.3390/atmos4040315] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Huang Z, Hua W, Verreault D, Allen HC. Influence of Salt Purity on Na+ and Palmitic Acid Interactions. J Phys Chem A 2013; 117:13412-8. [PMID: 24041145 DOI: 10.1021/jp406690p] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Zishuai Huang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Wei Hua
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Dominique Verreault
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Heather C. Allen
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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36
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Brzozowska A, Mugele F, Duits M. Stability and interactions in mixed monolayers of fatty acid derivatives on Artificial Sea Water. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.04.062] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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37
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Huang Z, Hua W, Verreault D, Allen HC. Salty glycerol versus salty water surface organization: bromide and iodide surface propensities. J Phys Chem A 2013; 117:6346-53. [PMID: 23663033 DOI: 10.1021/jp4020228] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Salty NaBr and NaI glycerol solution interfaces are examined in the OH stretching region using broadband vibrational sum frequency generation (VSFG) spectroscopy. Raman and infrared (IR) spectroscopy are used to further understand the VSFG spectroscopic signature. The VSFG spectra of salty glycerol solutions reveal that bromide and iodide anions perturb the interfacial glycerol organization in a manner similar as that found in aqueous halide salt solutions, thus confirming the presence of bromide and iodide anions at the glycerol surface. Surface tension measurements are consistent with the surface propensity suggested by the VSFG data and also show that the surface excess increases with increasing salt concentration, similar to that of water. In addition, iodide is shown to have more surface prevalence than bromide, as has also been determined from aqueous solutions. These results suggest that glycerol behaves similarly to water with respect to surface activity and solvation of halide anions at its air/liquid interface.
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Affiliation(s)
- Zishuai Huang
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
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Kumar N, Wang L, Siretanu I, Duits M, Mugele F. Salt dependent stability of stearic acid Langmuir-Blodgett films exposed to aqueous electrolytes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:5150-9. [PMID: 23565719 DOI: 10.1021/la400615j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We use contact angle goniometry, imaging ellipsometry, and atomic force microscopy to study the stability and wettability of Langmuir-Blodgett (LB) monolayers of stearic acid on silica substrates, upon drying and exposure to aqueous solutions of varying salinity. The influences of Ca(2+) and Na(+) ions are compared by varying their concentrations, both in the subphase before the LB transfer, and in the droplets to which the dried LB layers are exposed. Ca(2+) ions in the subphase are found to enhance the stability, leading to contact angles up to 100°, as compared to less than 5° for Na(+). Consistent with the macroscopic wettability, AFM images show almost intact films with few holes exposing bare substrate when prepared in the presence of Ca(2+), while subphases containing Na(+) result in large areas of bare substrate after exposure to aqueous drops. The observations on varying the composition of the droplets corroborate the stabilizing effect of Ca(2+). We attribute these findings to the cation-bridging ability of Ca(2+) ions, which can bind the negatively charged stearate groups to the negatively charged substrates. We discuss the relevance of our findings in the context of enhanced oil recovery.
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Affiliation(s)
- Naveen Kumar
- Physics of Complex Fluids Group and MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
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Verreault D, Hua W, Allen HC. From Conventional to Phase-Sensitive Vibrational Sum Frequency Generation Spectroscopy: Probing Water Organization at Aqueous Interfaces. J Phys Chem Lett 2012; 3:3012-3028. [PMID: 26292243 DOI: 10.1021/jz301179g] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Elucidation of water organization at aqueous interfaces has remained a challenging problem. Conventional vibrational sum frequency generation (VSFG) spectroscopy and its most recent extension, phase-sensitive VSFG (PS-VSFG), have emerged as powerful experimental methods for unraveling structural information at various aqueous interfaces. In this Perspective, we briefly describe the two possible VSFG detection modes, and we point out features that make these methods highly suited to address questions about water organization at air/aqueous interfaces. Several important aqueous interfacial systems are discussed to illustrate the versatility of these methods. Remaining challenges and exciting prospective directions are also presented.
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Affiliation(s)
- Dominique Verreault
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Wei Hua
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Heather C Allen
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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Kherb J, Flores SC, Cremer PS. Role of Carboxylate Side Chains in the Cation Hofmeister Series. J Phys Chem B 2012; 116:7389-97. [DOI: 10.1021/jp212243c] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Jaibir Kherb
- Department of Chemistry, Texas A & M University, College Station, Texas 77843, United States
| | - Sarah C. Flores
- Department of Chemistry, Texas A & M University, College Station, Texas 77843, United States
| | - Paul S. Cremer
- Department of Chemistry, Texas A & M University, College Station, Texas 77843, United States
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Jubb AM, Hua W, Allen HC. Environmental chemistry at vapor/water interfaces: insights from vibrational sum frequency generation spectroscopy. Annu Rev Phys Chem 2012; 63:107-30. [PMID: 22224702 DOI: 10.1146/annurev-physchem-032511-143811] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The chemistry that occurs at surfaces has been an intense area of study for many years owing to its complexity and importance in describing a wide range of physical phenomena. The vapor/water interface is particularly interesting from an environmental chemistry perspective as this surface plays host to a wide range of chemistries that influence atmospheric and geochemical interactions. The application of vibrational sum frequency generation (VSFG), an inherently surface-specific, even-order nonlinear optical spectroscopy, enables the direct interrogation of various vapor/aqueous interfaces to elucidate the behavior and reaction of chemical species within the surface regime. In this review we discuss the application of VSFG to the study of a variety of atmospherically important systems at the vapor/aqueous interface. Chemical systems presented include inorganic ionic solutions prevalent in aqueous marine aerosols, small molecular solutes, and long-chain fatty acids relevant to fat-coated aerosols. The ability of VSFG to probe both the organization and reactions that may occur for these systems is highlighted. A future perspective toward the application of VSFG to the study of environmental interfaces is also provided.
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Affiliation(s)
- Aaron M Jubb
- Department of Chemistry, The Ohio State University, Columbus, 43210, USA.
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Pereira RFP, Valente AJM, Fernandes M, Burrows HD. What drives the precipitation of long-chain calcium carboxylates (soaps) in aqueous solution? Phys Chem Chem Phys 2012; 14:7517-27. [DOI: 10.1039/c2cp24152h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Jiménez-Millán E, Giner-Casares JJ, Muñoz E, Martín-Romero MT, Camacho L. Self-assembly of Acridine Orange into H-aggregates at the air/water interface: tuning of orientation of headgroup. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:14888-14899. [PMID: 22029424 DOI: 10.1021/la2030236] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The surface active derivative of the organic dye Acridine Orange (N-10-dodecyl-acridine orange (DAO)) has been included in mixed Langmuir monolayers with stearic acid (SA). The maximum relative content on DAO for a stable mixed monolayer is a molar ratio of X(DAO) = 0.5. Brewster angle microscopy (BAM) reveals a high homogeneity at the micrometer level for the mixed monolayer in equimolar proportion (X(DAO) = 0.5), whereas the appearance of domains occurs for lower content of DAO, i.e., X(DAO) = 0.2 and 0.1. The aggregation of the DAO headgroup leads to well-defined H-aggregates at the air/water interface for those mixed monolayers with a low content of DAO. However, for the mixed monolayers enriched in DAO, e.g., X(DAO) = 0.5, the molecular crowding prevents the formation of defined supramolecular structures. Molecular organization and tilting of the DAO headgroup is quantitatively analyzed by in situ UV-visible reflection spectroscopy. The formation of H-aggregates of the DAO headgroup can be reversibly tuned with the applied surface pressure. A molecular mechanism for the conformational rearrangement of the DAO molecule is proposed using RM1 quantum semiempirical calculations.
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Affiliation(s)
- Eugenio Jiménez-Millán
- Department of Physical Chemistry and Applied Thermodynamics, University of Córdoba, Campus de Rabanales, Edificio Marie Curie, Córdoba, Spain E-14014
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Laß K, Friedrichs G. Revealing structural properties of the marine nanolayer from vibrational sum frequency generation spectra. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jc006609] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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