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Inhibition of Ice Crystallisation in Highly Viscous Aqueous Organic Acid Droplets : Volume 8, Issue 3 (14/05/2008)

By Murray, B. J.

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Book Id: WPLBN0003987160
Format Type: PDF Article :
File Size: Pages 29
Reproduction Date: 2015

Title: Inhibition of Ice Crystallisation in Highly Viscous Aqueous Organic Acid Droplets : Volume 8, Issue 3 (14/05/2008)  
Author: Murray, B. J.
Volume: Vol. 8, Issue 3
Language: English
Subject: Science, Atmospheric, Chemistry
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Historic
Publication Date:
2008
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

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Murray, B. J. (2008). Inhibition of Ice Crystallisation in Highly Viscous Aqueous Organic Acid Droplets : Volume 8, Issue 3 (14/05/2008). Retrieved from http://worldebooklibrary.com/


Description
Description: School of Chemistry, Woodhouse Lane, University of Leeds, Leeds LS2 9JT, UK. Homogeneous nucleation of ice within aqueous solution droplets and their subsequent crystallisation is thought to play a significant role in upper tropospheric ice cloud formation. It is normally assumed that homogeneous nucleation will take place at a threshold supersaturation, irrespective of the identity of the solute, and that rapid growth of ice particles will follow immediately after nucleation. However, it is shown here through laboratory experiments that droplets may not readily freeze in the very cold tropical tropopause layer (TTL, typical temperatures of 186–200 K). In these experiments ice crystal growth in citric acid solution droplets did not occur when ice nucleated below 197±6 K. Citric acid, 2-hydroxypropane-1,2,3-tricarboxyllic acid, is a molecule with similar functionality to oxygenated organic compounds which are ubiquitous to atmospheric aerosol and is therefore thought to be a sensible proxy for atmospheric organic material. Evidence is presented that suggest citric acid solution droplets become ultra-viscous or perhaps even glassy under atmospherically relevant conditions. Diffusion of liquid water molecules to ice nuclei is expected to be very slow in ultra-viscous solution droplets and this most likely provides an explanation for the experimentally observed inhibition of ice crystallisation. The implications of ultra-viscous solution droplets for ice cloud formation and supersaturations in the TTL are discussed.

Summary
Inhibition of ice crystallisation in highly viscous aqueous organic acid droplets

Excerpt
Duft, D. and Leisner, T.: Laboratory evidence for volume-dominated nucleation of ice in supercooled water microdroplets, Atmos. Chem. Phys., 4, 1997–2000, 2004.; Abbatt, J. P. D.: Interactions of atmospheric trace gases with ice surfaces: Adsorption and reaction, Chem. Rev., 103, 4783–4800, 2003.; Angel, C. A.: Liquid fragility and the glass transition in water and aqueous solutions, Chem. Rev., 102, 2627–2650, 2002.; Apelblat, A., Dov, M., Wisniak, J., and Zabicky, J.: Osmotic and activity coefficients of HO2CCH2C(OH)(CO2H)CH2CO2H (citric acid) in concentrated aqueous solutions at temperatures from 298.15 k to 318.15 k, J. Chem. Thermodyn., 27, 347–353, 1995.; Apelblat, A.: Cryoscopic studies in the citric acid-water system, J. Mol. Liq., 103-104, 201–210, 2003.; Bertram, A. K., Koop, T., Molina, L. T., and Molina, M. J.: Ice formation in (NH$_4)_2$SO4-H2O particles, J. Phys. Chem. A, 104, 584–588, 2000.; Bogdan, A., Molina, M. J., Sassen, K., and Kulmala, M.: Formation of low-temperature cirrus from h2so4/h2o aerosol droplets, J. Phys. Chem. A, 110, 12 541–12 542, 2006.; Cziczo, D. J., DeMott, P. J., Brooks, S. D., Prenni, A. J., Thomson, D. S., Baumgardner, D., Wilson, J. C., Kreidenweis, S. M., and Murphy, D. M.: Observations of organic species and atmospheric ice formation, Geophys. Res. Lett., 31, L12116, doi:10.1029/2004GL019822, 2004a.; Cziczo, D. J., Murphy, D. M., Hudson, P. K., and Thomson, D. S.: Single particle measurements of the chemical composition of cirrus ice residue during crystal-face, J. Geophys. Res.-Atmos., 109, D04201, doi:10.1029/2003JD004032, 2004b.; Debenedetti, P. G.: Metastable liquids concepts and principles, Princeton University Press, New Jersey, 1996.; DeMott, P. J.: Laboratory studies of cirrus cloud processes, in: Cirrus, edited by: Lynch, D. K., Sassen, K., Starr, D. C., and Stephens, G., Oxford University Press, Oxford, 102–135, 2002.; DeMott, P. J., Cziczo, D. J., Prenni, A. J., Murphy, D. M., Kreidenweis, S. M., Thomson, D. S., Borys, R., and Rogers, D. C.: Measurements of the concentration and composition of nuclei for cirrus formation, Proc. Natl. Acad. Sci. USA, 100, 14 655–14 660, 2003.; Denman, K. L., Brasseur, G., Chidthaisong, A., Ciais, P., Cox, P. M., Dickinson, R. E., Hauglustaine, D., Heinze, C., Holland, E., Jacob, D., Lohmann, U., Ramachandran, S., da Silva Dias, P. L., Wofsy, S. C., and Zhang, X.: Couplings between changes in the climate system and biogeochemistry, in: Climate change 2007: The physical science basis, Contribution of working group i to the fourth assessment report of the intergovernmental panel on climate change, edited by: Solomon, S. D., Qin, M., Manning, Z., Chen, M., Marquis, K. B., Averyt, M. T., and Miller, H. L., Cambridge University Press, Cambridge, 2007.; Dowell, L. G. and Rinfret, A. P.: Low-temperature forms of ice as studied by x-ray diffraction, Nature, 188, 1144–1148, 1960.; Falkovich, A. H., Graber, E. R., Schkolnik, G., Rudich, Y., Maenhaut, W., and Artaxo, P.: Low molecular weight organic acids in aerosol particles from rondonia, brazil, during the biomass-burning, transition and wet periods, Atm. Chem. Phys., 5, 781–797, 2005.; Gao, R. S., Popp, P. J., Fahey, D. W., Marcy, T. P., Herman, R. L., Weinstock, E. M., Baumgardner, D. G., Garrett, T. J., Rosenlof, K. H., Thompson, T. L., Bui, P. T., Ridley, B. A., Wofsy, S. C., Toon, O. B., Tolbert, M. A., Karcher, B., Peter, T., Hudson, P. K., Weinheimer, A. J., and Heymsfield, A. J.: Evidence that nitric acid increases relative humidity in low-temperature cirrus clouds, Science, 303, 516–520, 2004.; Gettelman, A. and Forster, P. M. D.: A climatology of the tropical tropopause layer, J. Meteorol. Soc. Jpn, 80, 911–924, 2002.; Graber, E. R. and Rudich, Y.: Atmospheric hulis: How humic-like are they? A comprehensive and cri

 

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