@article {956,
	title = {Deliquescence and crystallization of ammonium sulfate particles internally mixed with water-soluble organic compounds},
	journal = {Journal of Physical Chemistry A},
	volume = {108},
	number = {52},
	year = {2004},
	note = {ISI Document Delivery No.: 882FPTimes Cited: 38Cited Reference Count: 66},
	month = {Dec},
	pages = {11600-11608},
	type = {Article},
	abstract = {The deliquescence and crystallization of ammonium sulfate particles internally mixed with water-soluble organic material have been studied, restricted to an organic mass fraction of less than 0.6. The organic species used were malonic acid, glycerol, levoglucosan (1,6-anhydro-beta-D-glucopyranose), and Suwannee River fulvic acid. Our deliquescence results for systems with malonic acid and fulvic acid are in agreement with existing literature values. Glycerol deliquescence results are slightly lower than previous measurements. The levoglucosan results are the first of this kind. Total deliquescence relative humidities for the different systems are the same within the uncertainty of the measurements when the organic mole fraction is less than approximately 0.35. At an organic mole fraction of 0.6, the maximum deviation of total deliquescence relative humidities between the systems is approximately 10\% relative humidity. We show that thermodynamic calculations based on a simplified version of a model recently proposed by Clegg et al. (J. Aerosol Sci. 2001, 32, 713)1 are in agreement with measured values of deliquescence relative humidity up to an organic mole fraction of approximately 0.4 for most of the systems studied. The crystallization relative humidity (CRH) of mixed systems of ammonium sulfate with malonic acid, glycerol, or levoglucosan decreases significantly from the CRH of pure ammonium sulfate when the organic mole fraction is greater than about 0.25. This is in contrast to our previous study with glutaric acid where CRH remained close to CRH of pure ammonium sulfate up to a glutaric acid mole fraction of 0.4. CRH values are shown to vary depending on the type of,organic present. In terms of atmospheric implications, we estimate that organics, on average, are only a minor perturbation on the deliquescence relative humidity of the pure inorganic particles, whereas the organics, on average, may decrease the CRH of pure inorganic particles significantly and this effect depends on the type of organic material.},
	keywords = {ATMOSPHERIC AEROSOL, BLACK CARBON, DICARBOXYLIC-ACIDS, FINE AEROSOL, HUMIC-LIKE SUBSTANCES, HYGROSCOPIC PROPERTIES, MODEL, PHASE-TRANSITIONS, PHYSICAL, RELATIVE-HUMIDITY, STATE},
	isbn = {1089-5639},
	url = {<Go to ISI>://000225924800016},
	author = {Parsons, M. T. and Knopf, D. A. and Bertram, A. K.}
}
@article {955,
	title = {Deliquescence and crystallization of ammonium sulfate-glutaric acid and sodium chloride-glutaric acid particles},
	journal = {Geophysical Research Letters},
	volume = {31},
	number = {12},
	year = {2004},
	note = {ISI Document Delivery No.: 839HNTimes Cited: 24Cited Reference Count: 20},
	month = {Jun},
	pages = {4},
	type = {Article},
	abstract = {In the following, we report the deliquescence relative humidities (DRH) and crystallization relative humidities (CRH) of mixed inorganic-organic particles, specifically ammonium sulfate-glutaric acid and sodium chloride-glutaric acid particles. Knowledge of the DRH and CRH of mixed inorganic-organic particles is crucial for predicting the role of aerosol particles in the atmosphere. Our DRH results are in good agreement with previous measurements, but our CRH results are significantly lower than some of the previous measurements reported in the literature. Our studies show that the DRH and CRH of ammonium sulfate and sodium chloride only decreased slightly when the mole fraction of the acid was less than 0.4. If other organics in the atmosphere behave in a similar manner, then the DRH and CRH of mixed inorganic-organic atmospheric particles will only be slightly less than the DRH and CRH of pure inorganic particles when the organic mole fraction is less than 0.4. Our results also show that if the particles contain a significant amount of organics ( mole fraction>0.5) the crystallization relative humidity decreases significantly and the particles are more likely to remain in the liquid state. Further work is needed to determine if other organics species of atmospheric importance have a similar effect.},
	keywords = {AEROSOL, DICARBOXYLIC-ACIDS, PHYSICAL STATE},
	isbn = {0094-8276},
	url = {<Go to ISI>://000222774700005},
	author = {Pant, A. and Fok, A. and Parsons, M. T. and Mak, J. and Bertram, A. K.}
}
@article {957,
	title = {Deliquescence of malonic, succinic, glutaric, and adipic acid particles},
	journal = {Journal of Geophysical Research-Atmospheres},
	volume = {109},
	number = {D6},
	year = {2004},
	note = {ISI Document Delivery No.: 809FPTimes Cited: 32Cited Reference Count: 46},
	month = {Mar},
	pages = {8},
	type = {Article},
	abstract = {In order to understand and predict the role of organic particles in the atmosphere their deliquescence behavior must be understood. Using an optical microscope coupled to a flow cell, we investigated the deliquescence of malonic, succinic, glutaric, and adipic acid particles with sizes ranging from 2 to 40 mm. Deliquescence relative humidities were determined for temperatures ranging from 293 to 243 K. Over this temperature range both succinic acid and adipic acid deliquesced at approximately 100\% relative humidity, whereas malonic acid and glutaric acid deliquesced at significantly lower relative humidities. These results are generally in good agreement with previous studies and are within 3\% of calculations based on the UNIQUAC (universal quasi-chemical) Functional Group Activity Coefficients (UNIFAC) model and recently published interaction parameters. Our studies also include measurements at temperatures below the eutectic temperatures. At these temperatures, ice did not nucleate; rather the particles underwent deliquescence to form metastable solution droplets. This indicates that solid dicarboxylic acids are not good ice nuclei above 243 K and hence will probably not play a role in ice cloud formation at these temperatures.},
	keywords = {AEROSOL, AEROSOL PHASE, AMAZON BASIN, AMMONIUM-SULFATE, atmospheric chemistry, ATMOSPHERIC PARTICLES, CIRRUS CLOUD FORMATION, deliquescence, dicarboxylic acid, DICARBOXYLIC-ACIDS, HYGROSCOPIC GROWTH, ice, NUCLEATION, optical microscopy, PHASE-TRANSITIONS, STRATOSPHERIC TEMPERATURES, WATER},
	isbn = {0148-0227},
	url = {<Go to ISI>://000220622900002},
	author = {Parsons, M. T. and Mak, J. and Lipetz, S. R. and Bertram, A. K.}
}
