@article {2427,
	title = {Reactive uptake studies of NO3 and N2O5 on alkenoic acid, alkanoate, and polyalcohol substrates to probe nighttime aerosol chemistry},
	journal = {Physical Chemistry Chemical Physics},
	volume = {11},
	number = {36},
	year = {2009},
	note = {ISI Document Delivery No.: 491ADTimes Cited: 6Cited Reference Count: 86Gross, Simone Iannone, Richard Xiao, Song Bertram, Allan K.},
	pages = {7792-7803},
	type = {Article},
	abstract = {Heterogeneous reactions between NO3 and N2O5 and diethyl sebacate (DES), glycerol, oleic acid (OA), linoleic acid (LA), and conjugated linoleic acid (CLA) were studied to understand better nighttime aerosol chemistry. The reactive uptake coefficient of NO3 on the liquid alkenoic acids (OA, LA, and CLA) was found to be >0.07, which is higher than previous results for unsaturated organics, including alkenoic acids. This reaction could potentially be an important loss process of particle-phase unsaturated organic compounds in the atmosphere and in laboratory secondary organic aerosol studies. The reactive uptake coefficient of N2O5 on liquid glycerol was also found to be relatively large with a value of (3.2-8.5) x 10(-4), suggesting that N2O5 heterogeneous reactions with alcohols may also be atmospherically relevant. For all measurements with OA, CLA, and DES, the reactive uptake coefficients decreased significantly upon freezing. One possible explanation is that the liquid reaction is due to both a surface reaction and a bulk reaction and that the freezing process significantly decreases the importance of any bulk reactions. NO3 reactive uptake coefficients for liquid-phase compounds decreased in magnitude in the order: alkenoic acids > DES > glycerol. This is different compared to previous gas-phase studies and the difference may be due to the large viscosity of glycerol compared to the other organic compounds studied. N2O5 reactive uptake coefficients for liquid-phase compounds decreased in magnitude in the order: glycerol > LA > DES congruent to OA congruent to CLA.},
	keywords = {ATMOSPHERIC PARTICLES, CLOUD DROPLETS, DINITROGEN PENTOXIDE, GAS-PHASE DIFFUSION, HETEROGENEOUS OXIDATION, MIXED PARTICLES, OLEIC-ACID, RATE COEFFICIENT, SOLUBLE ORGANIC-COMPOUNDS, SULFURIC-ACID},
	isbn = {1463-9076},
	url = {<Go to ISI>://000269548300004},
	author = {Gross, S. and Iannone, R. and Xiao, S. and Bertram, A. K.}
}
@article {2198,
	title = {Inhibition of solute crystallisation in aqueous H+-NH4+-SO42{\textendash}H2O droplets},
	journal = {Physical Chemistry Chemical Physics},
	volume = {10},
	number = {22},
	year = {2008},
	note = {ISI Document Delivery No.: 304MXTimes Cited: 7Cited Reference Count: 68Murray, Benjamin J. Bertram, Allan K.},
	pages = {3287-3301},
	type = {Article},
	abstract = {Ice clouds in the Earth{\textquoteright}s upper troposphere can form via homogeneous nucleation of ice in aqueous droplets. In this study we investigate the crystallisation, or lack of crystallisation, of the solute phase and ice in aqueous (NH4)(3)H(SO4)(2)/H2O and NH4HSO4/H2O droplets. This is done using in situ X-ray diffraction of emulsified solution droplets mounted on a cold stage. From the diffraction patterns we are able to identify the phases of crystalline solute and ice that form after homogeneous freezing in micrometer sized droplets. An important finding from this study is that crystallisation of the solute does not always occur, even when crystallisation is strongly thermodynamically favoured. The nucleation and growth of solute phase crystals becomes inhibited since the viscosity of the aqueous brine most likely increases dramatically as the brine concentration increases and temperature decreases. If ice nucleates below a threshold freezing temperature, the brine appears to rapidly become so viscous that solute crystallisation is inhibited. This threshold temperature is 192 K and 180 K, in ( NH4) 3H( SO4) 2 and NH4HSO4, respectively. We also speculate that the formation of cubic ice within a highly viscous brine blocks the solvent mediated cubic to hexagonal phase transformation, thus stabilising the metastable cubic ice in the most concentrated solution droplets.},
	keywords = {CUBIC ICE, GLASS-TRANSITION, H2SO4/NH3/H2O AEROSOL-PARTICLES, HOMOGENEOUS ICE NUCLEATION, LIQUID WATER, LOW-TEMPERATURES, NH4HSO4, PHASE-TRANSITIONS, solutions, SULFURIC-ACID, SUPERCOOLED WATER},
	isbn = {1463-9076},
	url = {<Go to ISI>://000256114700013},
	author = {Murray, B. J. and Bertram, A. K.}
}
