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Moffet RC, Henn T, Laskin A, Gilles MK. Automated Chemical Analysis of Internally Mixed Aerosol Particles Using X-ray Spectromicroscopy at the Carbon K-Edge. Anal Chem 2010; 82:7906-14. [DOI: 10.1021/ac1012909] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Pratt KA, Twohy CH, Murphy SM, Moffet RC, Heymsfield AJ, Gaston CJ, DeMott PJ, Field PR, Henn TR, Rogers DC, Gilles MK, Seinfeld JH, Prather KA. Observation of playa salts as nuclei in orographic wave clouds. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013606] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Zaveri RA, Berkowitz CM, Brechtel FJ, Gilles MK, Hubbe JM, Jayne JT, Kleinman LI, Laskin A, Madronich S, Onasch TB, Pekour MS, Springston SR, Thornton JA, Tivanski AV, Worsnop DR. Nighttime chemical evolution of aerosol and trace gases in a power plant plume: Implications for secondary organic nitrate and organosulfate aerosol formation, NO3radical chemistry, and N2O5heterogeneous hydrolysis. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013250] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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de Smit E, Swart I, Creemer JF, Hoveling GH, Gilles MK, Tyliszczak T, Kooyman PJ, Zandbergen HW, Morin C, Weckhuysen BM, de Groot FMF. Nanoscale chemical imaging of a working catalyst by scanning transmission X-ray microscopy. Nature 2008; 456:222-5. [PMID: 19005551 DOI: 10.1038/nature07516] [Citation(s) in RCA: 241] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2008] [Accepted: 09/24/2008] [Indexed: 01/09/2023]
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Moffet RC, Desyaterik Y, Hopkins RJ, Tivanski AV, Gilles MK, Wang Y, Shutthanandan V, Molina LT, Abraham RG, Johnson KS, Mugica V, Molina MJ, Laskin A, Prather KA. Characterization of aerosols containing Zn, Pb, and Cl from an industrial region of Mexico City. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:7091-7097. [PMID: 18939531 DOI: 10.1021/es7030483] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Recent ice core measurements show lead concentrations increasing since 1970, suggesting new nonautomobile-related sources of Pb are becoming important worldwide (1). Developing a full understanding of the major sources of Pb and other metals is critical to controlling these emissions. During the March, 2006 MILAGRO campaign, single particle measurements in Mexico City revealed the frequent appearance of particles internally mixed with Zn, Pb, Cl, and P. Pb concentrations were as high as 1.14 microg/m3 in PM10 and 0.76 microg/m3 in PM2.5. Real time measurements were used to select time periods of interest to perform offline analysis to obtain detailed aerosol speciation. Many Zn-rich particles had needle-like structures and were found to be composed of ZnO and/or Zn(NO3)2 x 6H2O. The internally mixed Pb-Zn-Cl particles represented as much as 73% of the fine mode particles (by number) in the morning hours between 2-5 am. The Pb-Zn-Cl particles were primarily in the submicrometer size range and typically mixed with elemental carbon suggesting a combustion source. The unique single particle chemical associations measured in this study closely match signatures indicative of waste incineration. Our findings also show these industrial emissions play an important role in heterogeneous processing of NO(y) species. Primary emissions of metal and sodium chloride particles emitted by the same source underwent heterogeneous transformations into nitrate particles as soon as photochemical production of nitric acid began each day at approximately 7 am.
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Hopkins RJ, Desyaterik Y, Tivanski AV, Zaveri RA, Berkowitz CM, Tyliszczak T, Gilles MK, Laskin A. Chemical speciation of sulfur in marine cloud droplets and particles: Analysis of individual particles from the marine boundary layer over the California current. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd008954] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Messer BM, Cappa CD, Smith JD, Wilson KR, Gilles MK, Cohen RC, Saykally RJ. pH dependence of the electronic structure of glycine. J Phys Chem B 2007; 109:5375-82. [PMID: 16863204 DOI: 10.1021/jp0457592] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The carbon, nitrogen, and oxygen K-edge spectra were measured for aqueous solutions of glycine by total electron yield near-edge X-ray absorption fine structure (TEY NEXAFS) spectroscopy. The bulk solution pH was systematically varied while maintaining a constant amino acid concentration. Spectra were assigned through comparisons with both previous studies and ab initio computed spectra of isolated glycine molecules and hydrated glycine clusters. Nitrogen K-edge solution spectra recorded at low and moderate pH are nearly identical to those of solid glycine, whereas basic solution spectra strongly resemble those of the gas phase. The carbon 1s --> pi*(C=O) transition exhibits a 0.2 eV red shift at high pH due to the deprotonation of the amine terminus. This deprotonation also effects a 1.4 eV red shift in the nitrogen K-edge at high pH. Two sharp preedge features at 401.3 and 402.5 eV are also observed at high pH. These resonances, previously observed in the vapor-phase ISEELS spectrum of glycine, have been reassigned as transitions to sigma* bound states. The observation of these peaks indicates that the amine moiety is in an acceptor-only hydrogen bond configuration at high pH. At low pH, the oxygen 1s --> pi*(C=O) transition exhibits a 0.25-eV red shift due to the protonation of the carboxylic acid terminus. These spectral differences indicate that the variations in electronic structure observed in the NEXAFS spectra are determined by the internal charge state and hydration environment of the molecule in solution.
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Tivanski AV, Hopkins RJ, Tyliszczak T, Gilles MK. Oxygenated Interface on Biomass Burn Tar Balls Determined by Single Particle Scanning Transmission X-ray Microscopy. J Phys Chem A 2007; 111:5448-58. [PMID: 17542565 DOI: 10.1021/jp070155u] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Carbonaceous particles originating from biomass burning can account for a large fraction of organic aerosols in a local environment. Presently, their composition, physical and chemical properties, as well as their environmental effects are largely unknown. Tar balls, a distinct type of highly spherical carbonaceous biomass burn particles, have been observed in a number of field campaigns. The Yosemite Aerosol Characterization Study that took place in summer 2002 occurred during an active fire season in the western United States; tar balls collected during this field campaign are described in this article. Scanning transmission X-ray microscopy and near-edge X-ray absorption fine structure spectroscopy are used to determine the shape, structure, and size-dependent chemical composition of approximately 150 individual spherical particles ranging in size from 0.15 to 1.2 mum. The elemental composition of tar balls is approximately 55% atomic carbon and approximately 45% atomic oxygen. Oxygen is present primarily as carboxylic carbonyls and oxygen-substituted alkyl (O-alkyl-C) functional groups, followed by moderate amounts of ketonic carbonyls. The observed chemical composition, density, and carbon functional groups are distinctly different from soot or black carbon and more closely resemble high molecular weight polymeric humic-like substances, which could account for their reported optical properties. A detailed examination of the carboxylic carbonyl and O-alkyl-C functional groups as a function of particle size reveals a thin oxygenated interface layer. The high oxygen content, as well as the presence of water-soluble carboxylic carbonyl groups, could account for the reported hygroscopic properties of tar balls. The presence of the oxygenated layer is attributed to atmospheric processing of biomass burn particles.
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Michelsen HA, Tivanski AV, Gilles MK, van Poppel LH, Dansson MA, Buseck PR. Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope. APPLIED OPTICS 2007; 46:959-77. [PMID: 17279144 DOI: 10.1364/ao.46.000959] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We investigated the physical and chemical changes induced in soot aggregates exposed to laser radiation using a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope to perform near-edge x-ray absorption fine structure spectroscopy. Laser-induced nanoparticle production was observed at fluences above 0.12 J/cm(2) at 532 nm and 0.22 J/cm(2) at 1064 nm. Our results indicate that new particle formation proceeds via (1) vaporization of small carbon clusters by thermal or photolytic mechanisms, followed by homogeneous nucleation, (2) heterogeneous nucleation of vaporized carbon clusters onto material ablated from primary particles, or (3) both processes.
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Davis ME, Gilles MK, Ravishankara AR, Burkholder JB. Rate coefficients for the reaction of OH with (E)-2-pentenal, (E)-2-hexenal, and (E)-2-heptenal. Phys Chem Chem Phys 2007; 9:2240-8. [PMID: 17487321 DOI: 10.1039/b700235a] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Rate coefficients for the gas-phase reaction of the OH radical with (E)-2-pentenal (CH(3)CH(2)CH[double bond]CHCHO), (E)-2-hexenal (CH(3)(CH(2))(2)CH[double bond]CHCHO), and (E)-2-heptenal (CH(3)(CH(2))(3)CH[double bond]CHCHO), a series of unsaturated aldehydes, over the temperature range 244-374 K at pressures between 23 and 150 Torr (He, N(2)) are reported. Rate coefficients were measured under pseudo-first-order conditions in OH with OH radicals produced via pulsed laser photolysis of HNO(3) or H(2)O(2) at 248 nm and detected by pulsed laser-induced fluorescence. The rate coefficients were independent of pressure and the room temperature rate coefficients and Arrhenius expressions obtained are (cm(3) molecule(-1) s(-1) units): k(1)(297 K)=(4.3 +/- 0.6)x 10(-11), k(1)(T)=(7.9 +/- 1.2)x 10(-12) exp[(510 +/- 20)/T]; k(2)(297 K)=(4.4 +/- 0.5)x 10(-11), k(2)(T)=(7.5 +/- 1.1)x 10(-12) exp[(520 +/- 30)/T]; and k(3)(297 K)=(4.4 +/- 0.7)x 10(-11), k(3)(T)=(9.7 +/- 1.5)x 10(-12) exp[(450 +/- 20)/T] for (E)-2-pentenal, (E)-2-hexenal and (E)-2-heptenal, respectively. The quoted uncertainties are 2sigma(95% confidence level) and include estimated systematic errors. Rate coefficients are compared with previously published room temperature values and the discrepancies are discussed. The atmospheric degradation of unsaturated aldehydes is also discussed.
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Sandford SA, Aléon J, Alexander CMO, Araki T, Bajt S, Baratta GA, Borg J, Bradley JP, Brownlee DE, Brucato JR, Burchell MJ, Busemann H, Butterworth A, Clemett SJ, Cody G, Colangeli L, Cooper G, D'Hendecourt L, Djouadi Z, Dworkin JP, Ferrini G, Fleckenstein H, Flynn GJ, Franchi IA, Fries M, Gilles MK, Glavin DP, Gounelle M, Grossemy F, Jacobsen C, Keller LP, Kilcoyne ALD, Leitner J, Matrajt G, Meibom A, Mennella V, Mostefaoui S, Nittler LR, Palumbo ME, Papanastassiou DA, Robert F, Rotundi A, Snead CJ, Spencer MK, Stadermann FJ, Steele A, Stephan T, Tsou P, Tyliszczak T, Westphal AJ, Wirick S, Wopenka B, Yabuta H, Zare RN, Zolensky ME. Organics Captured from Comet 81P/Wild 2 by the Stardust Spacecraft. Science 2006; 314:1720-4. [PMID: 17170291 DOI: 10.1126/science.1135841] [Citation(s) in RCA: 463] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Organics found in comet 81P/Wild 2 samples show a heterogeneous and unequilibrated distribution in abundance and composition. Some organics are similar, but not identical, to those in interplanetary dust particles and carbonaceous meteorites. A class of aromatic-poor organic material is also present. The organics are rich in oxygen and nitrogen compared with meteoritic organics. Aromatic compounds are present, but the samples tend to be relatively poorer in aromatics than are meteorites and interplanetary dust particles. The presence of deuterium and nitrogen-15 excesses suggest that some organics have an interstellar/protostellar heritage. Although the variable extent of modification of these materials by impact capture is not yet fully constrained, a diverse suite of organic compounds is present and identifiable within the returned samples.
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Brownlee D, Tsou P, Aléon J, Alexander CMO, Araki T, Bajt S, Baratta GA, Bastien R, Bland P, Bleuet P, Borg J, Bradley JP, Brearley A, Brenker F, Brennan S, Bridges JC, Browning ND, Brucato JR, Bullock E, Burchell MJ, Busemann H, Butterworth A, Chaussidon M, Cheuvront A, Chi M, Cintala MJ, Clark BC, Clemett SJ, Cody G, Colangeli L, Cooper G, Cordier P, Daghlian C, Dai Z, D'Hendecourt L, Djouadi Z, Dominguez G, Duxbury T, Dworkin JP, Ebel DS, Economou TE, Fakra S, Fairey SAJ, Fallon S, Ferrini G, Ferroir T, Fleckenstein H, Floss C, Flynn G, Franchi IA, Fries M, Gainsforth Z, Gallien JP, Genge M, Gilles MK, Gillet P, Gilmour J, Glavin DP, Gounelle M, Grady MM, Graham GA, Grant PG, Green SF, Grossemy F, Grossman L, Grossman JN, Guan Y, Hagiya K, Harvey R, Heck P, Herzog GF, Hoppe P, Hörz F, Huth J, Hutcheon ID, Ignatyev K, Ishii H, Ito M, Jacob D, Jacobsen C, Jacobsen S, Jones S, Joswiak D, Jurewicz A, Kearsley AT, Keller LP, Khodja H, Kilcoyne ALD, Kissel J, Krot A, Langenhorst F, Lanzirotti A, Le L, Leshin LA, Leitner J, Lemelle L, Leroux H, Liu MC, Luening K, Lyon I, Macpherson G, Marcus MA, Marhas K, Marty B, Matrajt G, McKeegan K, Meibom A, Mennella V, Messenger K, Messenger S, Mikouchi T, Mostefaoui S, Nakamura T, Nakano T, Newville M, Nittler LR, Ohnishi I, Ohsumi K, Okudaira K, Papanastassiou DA, Palma R, Palumbo ME, Pepin RO, Perkins D, Perronnet M, Pianetta P, Rao W, Rietmeijer FJM, Robert F, Rost D, Rotundi A, Ryan R, Sandford SA, Schwandt CS, See TH, Schlutter D, Sheffield-Parker J, Simionovici A, Simon S, Sitnitsky I, Snead CJ, Spencer MK, Stadermann FJ, Steele A, Stephan T, Stroud R, Susini J, Sutton SR, Suzuki Y, Taheri M, Taylor S, Teslich N, Tomeoka K, Tomioka N, Toppani A, Trigo-Rodríguez JM, Troadec D, Tsuchiyama A, Tuzzolino AJ, Tyliszczak T, Uesugi K, Velbel M, Vellenga J, Vicenzi E, Vincze L, Warren J, Weber I, Weisberg M, Westphal AJ, Wirick S, Wooden D, Wopenka B, Wozniakiewicz P, Wright I, Yabuta H, Yano H, Young ED, Zare RN, Zega T, Ziegler K, Zimmerman L, Zinner E, Zolensky M. Comet 81P/Wild 2 Under a Microscope. Science 2006; 314:1711-6. [PMID: 17170289 DOI: 10.1126/science.1135840] [Citation(s) in RCA: 740] [Impact Index Per Article: 41.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales.
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Drake IJ, Zhang Y, Gilles MK, Teris Liu CN, Nachimuthu P, Perera RCC, Wakita H, Bell AT. An In Situ Al K-Edge XAS Investigation of the Local Environment of H +- and Cu +-Exchanged USY and ZSM-5 Zeolites. J Phys Chem B 2006. [DOI: 10.1021/jp068083e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Drake IJ, Zhang Y, Gilles MK, Teris Liu CN, Nachimuthu P, Perera RCC, Wakita H, Bell AT. An In Situ Al K-Edge XAS Investigation of the Local Environment of H+- and Cu+-Exchanged USY and ZSM-5 Zeolites. J Phys Chem B 2006; 110:11665-76. [PMID: 16800461 DOI: 10.1021/jp058244z] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Aluminum coordination in the framework of USY and ZSM-5 zeolites containing charge-compensating cations (NH4+, H+, or Cu+) was investigated by Al K-edge EXAFS and XANES. This work was performed using a newly developed in-situ cell designed especially for acquiring soft X-ray absorption data. Both tetrahedrally and octahedrally coordinated Al were observed for hydrated H-USY and H-ZSM-5, in good agreement with 27Al NMR analyses. Upon dehydration, water desorbed from the zeolite, and octahedrally coordinated Al was converted progressively to tetrahedrally coordinated Al. These observations confirmed the hypothesis that the interaction of water with Brønsted acid protons can lead to octahedral coordination of Al without loss of Al from the zeolite lattice. When H+ is replaced with NH4+ or Cu+, charge compensating species that absorb less water, less octahedrally coordinated Al was observed. Analysis of Al K-edge EXAFS data indicates that the Al-O bond distance for tetrahedrally coordinated Al in dehydrated USY and ZSM-5 is 1.67 angstroms. Simulation of k3chi(k) for Cu+ exchanged ZSM-5 leads to an estimated distance between Cu+ and framework Al atoms of 2.79 angstroms.
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De Stasio G, Rajesh D, Ford JM, Daniels MJ, Erhardt RJ, Frazer BH, Tyliszczak T, Gilles MK, Conhaim RL, Howard SP, Fowler JF, Estève F, Mehta MP. Motexafin-Gadolinium Taken Up In vitro by at Least 90% of Glioblastoma Cell Nuclei. Clin Cancer Res 2006; 12:206-13. [PMID: 16397044 DOI: 10.1158/1078-0432.ccr-05-0743] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE We present preclinical data showing the in vitro intranuclear uptake of motexafin gadolinium by glioblastoma multiforme cells, which could serve as a prelude to the future development of radiosensitizing techniques, such as gadolinium synchrotron stereotactic radiotherapy (GdSSR), a new putative treatment for glioblastoma multiforme. EXPERIMENTAL DESIGN In this approach, administration of a tumor-seeking Gd-containing compound would be followed by stereotactic external beam radiotherapy with 51-keV photons from a synchrotron source. At least two criteria must be satisfied before this therapy can be established: Gd must accumulate in cancer cells and spare the normal tissue; Gd must be present in almost all the cancer cell nuclei. We address the in vitro intranuclear uptake of motexafin gadolinium in this article. We analyzed the Gd distribution with subcellular resolution in four human glioblastoma cell lines, using three independent methods: two novel synchrotron spectromicroscopic techniques and one confocal microscopy. We present in vitro evidence that the majority of the cell nuclei take up motexafin gadolinium, a drug that is known to selectively reach glioblastoma multiforme. RESULTS With all three methods, we found Gd in at least 90% of the cell nuclei. The results are highly reproducible across different cell lines. The present data provide evidence for further studies, with the goal of developing GdSSR, a process that will require further in vivo animal and future clinical studies.
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Cappa CD, Smith JD, Wilson KR, Messer BM, Gilles MK, Cohen RC, Saykally RJ. Effects of Alkali Metal Halide Salts on the Hydrogen Bond Network of Liquid Water. J Phys Chem B 2005; 109:7046-52. [PMID: 16851801 DOI: 10.1021/jp0445324] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Measurements of the oxygen K-edge X-ray absorption spectrum (XAS) of aqueous sodium halide solutions demonstrate that ions significantly perturb the electronic structure of adjacent water molecules. The addition of halide salts to water engenders an increase in the preedge intensity and a decrease in the postedge intensity of the XAS, analogous to those observed when increasing the temperature of pure water. The main-edge feature exhibits unique behavior and becomes more intense when salt is added. Density functional theory calculations of the XAS indicate that the observed red shift of the water transitions as a function of salt concentration arises from a strong, direct perturbation of the unoccupied molecular orbitals on water by anions, and does not require significant distortion of the hydrogen bond network beyond the first solvation shell. This contrasts the temperature-dependent spectral variations, which result primarily from intensity changes of specific transitions due to geometric rearrangement of the hydrogen bond network.
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Maria SF, Russell LM, Gilles MK, Myneni SCB. Organic Aerosol Growth Mechanisms and Their Climate-Forcing Implications. Science 2004; 306:1921-4. [PMID: 15591199 DOI: 10.1126/science.1103491] [Citation(s) in RCA: 226] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Surface- and volume-limited chemical reactions on and in atmospheric aerosol particles cause growth while changing organic composition by 13 to 24% per day. Many of these particles contain carbonaceous components from mineral dust and combustion emissions in Africa, Asia, and North America and reveal reaction rates that are three times slower than those typically used in climate models. These slower rates for converting from volatile or hydrophobic to condensed and hygroscopic organic compounds increase carbonaceous particle burdens in climate models by 70%, producing organic aerosol climate forcings of as much as -0.8 watt per square meter cooling and +0.3 watt per square meter warming.
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McCabe DC, Brown SS, Gilles MK, Talukdar RK, Smith IWM, Ravishankara AR. Kinetics of the Removal of OH(v = 1) and OD(v = 1) by HNO3 and DNO3 from 253 to 383 K. J Phys Chem A 2003. [DOI: 10.1021/jp0346413] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Gierczak T, Gilles MK, Bauerle S, Ravishankara AR. Reaction of Hydroxyl Radical with Acetone. 1. Kinetics of the Reactions of OH, OD, and 18OH with Acetone and Acetone-d6. J Phys Chem A 2003. [DOI: 10.1021/jp027301a] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Gilles MK, Burkholder JB, Gierczak T, Marshall P, Ravishankara AR. Rate Coefficient and Product Branching Measurements for the Reaction OH + Bromopropane from 230 to 360 K. J Phys Chem A 2002. [DOI: 10.1021/jp014736+] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Polak ML, Gilles MK, Ho J, Lineberger WC. Photoelectron spectroscopy of copper oxide (CuO-). ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100162a005] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gilles MK, Lineberger WC, Ervin KM. Photoelectron spectroscopy of the monofluorovinylidene and difluorovinylidene anions: the monofluorovinylidene-fluoroacetylene rearrangement. J Am Chem Soc 2002. [DOI: 10.1021/ja00056a030] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ervin KM, Gronert S, Barlow SE, Gilles MK, Harrison AG, Bierbaum VM, DePuy CH, Lineberger WC, Ellison GB. Bond strengths of ethylene and acetylene. J Am Chem Soc 2002. [DOI: 10.1021/ja00171a013] [Citation(s) in RCA: 355] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gilles MK, Ervin KM, Ho J, Lineberger WC. Negative ion photoelectron spectroscopy of halocarbene anions (HCF-, HCCl-, HCBr-, and HCI-); photoelectron angular distributions and neutral triplet excitation energies. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100182a021] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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50
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Gilles MK, McCabe DC, Burkholder JB, Ravishankara AR. Measurement of the Rate Coefficient for the Reaction of OH with BrO. J Phys Chem A 2001. [DOI: 10.1021/jp0039666] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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