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- W2276908705 abstract "A high vacuum Knudsen flow reactor was used to determine the reactive uptake coefficient, γ, of isoprene on sulfuric acid films as a function of sulfuric acid weight percent, temperature, and relative humidity. No discernible dependence was observed for γ over the range of temperatures (220 − 265 K) and pressures (10 −7 Torr -10−4 Torr) studied. However, the uptake coefficient increased with increased sulfuric acid concentration between the range of 78 wt % (γ i 10 −4 ) and 93 wt % (γ i 10 −3 ). In addition to the Knudsen Cell, a bulk study was conducted between 60 and 85 wt % H 2 SO 4 to quantify uptake at lower acid concentrations and to determine reaction products. After exposing sulfuric acid to gaseous isoprene the condensed phase products were extracted and analyzed using gas chromatography/mass spectrometry (GC/MS). Isoprene was observed to polymerize in the sulfuric acid and form yellow/red colored monoterpenes and cyclic sesquiterpenes. Finally, addition of water to the 85 wt % sulfuric acid/isoprene product mixture released these terpenes from the condensed phase into the gas phase. Together these experiments imply that direct isoprene uptake will not produce significant SOA; however, terpene production from the small uptake may be relevant for ultrafine particles and could affect growth and nucleation. Several laboratory and field studies have suggested that the simple aldehyde glyoxal could be a significant source of secondary organic aerosol (SOA) in the lower troposphere. However, recent studies have found that particles in the upper troposphere also contain significant amounts of organic material, with average organic mass fractions as high as 70%. We have examined whether glyoxal could be a source of SOA in the upper troposphere. The uptake of glyoxal to aerosols generally requires the presence of liquid water. Aerosols in the upper troposphere that could have supercooled liquid on the surface are cirrus ice and particles containing hygroscopic organic material. Several studies indicate cirrus ice may be coated with supercooled liquid HNO 3 /H 2 O. Thus we have utilized a high vacuum Knudsen Cell to measure the uptake of glyoxal on ice exposed to nitric acid at temperatures and pressures relevant to the upper troposphere. Here we present kinetic and spectroscopic data that indicates uptake of glyoxal is efficient on these films and irreversible. Spectroscopic data indicates the glyoxal is oxidized to glyoxylic acid, and the presence of glyoxylic acid has been confirmed via derivatization of the products followed by gas chromatography mass spectrometry. We have used the glyoxylic acid products from the ice experiments to test whether hygroscopic organic material exposed to water and nitric vapour would also uptake glyoxal. We have found that the uptake of glyoxal and oxidation to glyoxylic acid occurs in the presence of supercooled HNO 3 /H 2 O liquid on glyoxylic acid even at water…" @default.
- W2276908705 created "2016-06-24" @default.
- W2276908705 creator A5060345066 @default.
- W2276908705 date "2010-01-01" @default.
- W2276908705 modified "2023-09-27" @default.
- W2276908705 title "Laboratory Studies of Heterogeneous Chemistry" @default.
- W2276908705 cites W1485685653 @default.
- W2276908705 cites W1495482938 @default.
- W2276908705 cites W1564094774 @default.
- W2276908705 cites W1585803698 @default.
- W2276908705 cites W1587101236 @default.
- W2276908705 cites W1626331569 @default.
- W2276908705 cites W1644074212 @default.
- W2276908705 cites W1647221725 @default.
- W2276908705 cites W1666891192 @default.
- W2276908705 cites W1907185040 @default.
- W2276908705 cites W1963594440 @default.
- W2276908705 cites W1965398049 @default.
- W2276908705 cites W1965594323 @default.
- W2276908705 cites W1966440503 @default.
- W2276908705 cites W1969821786 @default.
- W2276908705 cites W1977516364 @default.
- W2276908705 cites W1977690011 @default.
- W2276908705 cites W1978581851 @default.
- W2276908705 cites W1980809934 @default.
- W2276908705 cites W1982505433 @default.
- W2276908705 cites W1982775534 @default.
- W2276908705 cites W1982808948 @default.
- W2276908705 cites W1983641696 @default.
- W2276908705 cites W1984484393 @default.
- W2276908705 cites W1985290307 @default.
- W2276908705 cites W1988911477 @default.
- W2276908705 cites W1989092885 @default.
- W2276908705 cites W1992169027 @default.
- W2276908705 cites W1997137239 @default.
- W2276908705 cites W1998357501 @default.
- W2276908705 cites W1999548826 @default.
- W2276908705 cites W2001012574 @default.
- W2276908705 cites W2002570697 @default.
- W2276908705 cites W2002652137 @default.
- W2276908705 cites W2002982924 @default.
- W2276908705 cites W2007732183 @default.
- W2276908705 cites W2008092456 @default.
- W2276908705 cites W2008865901 @default.
- W2276908705 cites W2009835605 @default.
- W2276908705 cites W2011166648 @default.
- W2276908705 cites W2011254556 @default.
- W2276908705 cites W2011764801 @default.
- W2276908705 cites W2016565975 @default.
- W2276908705 cites W2022711024 @default.
- W2276908705 cites W2026029742 @default.
- W2276908705 cites W2028621310 @default.
- W2276908705 cites W2030266196 @default.
- W2276908705 cites W2030620915 @default.
- W2276908705 cites W2032469534 @default.
- W2276908705 cites W2032644412 @default.
- W2276908705 cites W2033745265 @default.
- W2276908705 cites W2034143857 @default.
- W2276908705 cites W2034636109 @default.
- W2276908705 cites W2035618697 @default.
- W2276908705 cites W2036036726 @default.
- W2276908705 cites W2037029984 @default.
- W2276908705 cites W2037203590 @default.
- W2276908705 cites W2038603452 @default.
- W2276908705 cites W2041033720 @default.
- W2276908705 cites W2042612674 @default.
- W2276908705 cites W2043648557 @default.
- W2276908705 cites W2044753020 @default.
- W2276908705 cites W2046343796 @default.
- W2276908705 cites W2047442548 @default.
- W2276908705 cites W2047734533 @default.
- W2276908705 cites W2048817008 @default.
- W2276908705 cites W2048826254 @default.
- W2276908705 cites W2048930322 @default.
- W2276908705 cites W2052859509 @default.
- W2276908705 cites W2054668571 @default.
- W2276908705 cites W2057733620 @default.
- W2276908705 cites W2062196534 @default.
- W2276908705 cites W2063426663 @default.
- W2276908705 cites W2067209936 @default.
- W2276908705 cites W2067342479 @default.
- W2276908705 cites W2070484130 @default.
- W2276908705 cites W2072621214 @default.
- W2276908705 cites W2078261188 @default.
- W2276908705 cites W2080955504 @default.
- W2276908705 cites W2081306247 @default.
- W2276908705 cites W2084268545 @default.
- W2276908705 cites W2084268854 @default.
- W2276908705 cites W2084300465 @default.
- W2276908705 cites W2084387349 @default.
- W2276908705 cites W2085767616 @default.
- W2276908705 cites W2090646981 @default.
- W2276908705 cites W2091725646 @default.
- W2276908705 cites W2092168539 @default.
- W2276908705 cites W2094089284 @default.
- W2276908705 cites W2095780621 @default.
- W2276908705 cites W2096286248 @default.
- W2276908705 cites W2096888179 @default.
- W2276908705 cites W2097727116 @default.
- W2276908705 cites W2104093336 @default.