{"89481":{"#nid":"89481","#data":{"type":"event","title":"(11-0607) Prof. Ehud Pines, Ben Gurion University","body":[{"value":"\u003Cp\u003EProf. Ehud Pines, Ben Gurion University\n\u003C\/p\u003E\n\u003Cp\u003EDirect observation of the dynamics of carbonic acid\/bicarbonate buffer in aqueous environment\n\u003C\/p\u003E\n\u003Cp\u003EThe bicarbonate\/carbonic-acid buffer is spontaneously generated when atmospheric CO\u003Csub\u003E2\u003C\/sub\u003E react with water according to CO\u003Csub\u003E2\u003C\/sub\u003E + H\u003Csub\u003E2\u003C\/sub\u003EO = HCO\u003Csub\u003E3\u003C\/sub\u003E- + H + =  H\u003Csub\u003E2\u003C\/sub\u003ECO\u003Csub\u003E3\u003C\/sub\u003E and is the main pH-stabilizing agent in nature controlling the pH of the oceans and of large fresh-water reservoirs as well as the pH of blood. We have recently demonstrated that H\u003Csub\u003E2\u003C\/sub\u003ECO\u003Csub\u003E3\u003C\/sub\u003E may be generated within a few hundreds of ps and that it has remained completely stable during our time-window of observation which was about 1 ns [1]. The carbonic acid, for a long time a species of elusive nature in aqueous solution, was generated by the rapid protonation of HCO\u003Csub\u003E3\u003C\/sub\u003E- ions utilizing optically  excited photoacids [2], a technique we developed to investigate ultrafast acid-base reactions in aqueous solutions [3,4]. We have also demonstrated using Marcus correlation that the Br\u00c3\u00b8nsted acidity of carbonic acid is slightly larger than that of formic acid. Considering its now proven ns-stability in aqueous solutions and its considerable acid-strength, intact carbonic acid  should be regarded a highly reactive  molecule by its own merit.\n\u003C\/p\u003E\n\u003Cp\u003EOur experimental results suggest new insights concerning the reactivity of the bicarbonate\/carbonic acid buffer under conditions relevant for ecology, biophysiology, marine biology and planning for large scale CO\u003Csub\u003E2\u003C\/sub\u003E sequestration projects aiming to reduce the green-house effect of  CO\u003Csub\u003E2\u003C\/sub\u003E by reducing its partial pressure in the atmosphere.\n\u003C\/p\u003E\n\u003Cp\u003EReferences\u003Cbr \/\u003E\n1. Adamczyk, K.,  Pr\u00c3\u00a9mont-Schwarz, M.,  Pines, D.,   Pines E., Nibbering E. T. J., Science  326 (2009) 1690.\u003Cbr \/\u003E\n2. Tolbert, L. M.; Solntsev, K. M.,  Acc. Chem. Res., 35 (2002) 19.\u003Cbr \/\u003E\n3. Rini, M., Magnes, B.-Z., Pines, E., Nibbering, E. T. J., Science 301 (2003) 349.\u003Cbr \/\u003E\n4. Mohammed, O. F., Pines, D., Dreyer, J., Pines. E., and Nibbering, E. T. J., Science 310  (2005( 83.\n\u003C\/p\u003E\n\u003Cp\u003EFor more information contact \u003Ca href=\u0022mailto:laren.tolbert@chemistry.gatech.edu\u0022\u003EProf. Laren Tolbert\u003C\/a\u003E (404-894-4093).\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"Prof. Ehud Pines, Ben Gurion University\n\nDirect observation of the dynamics of carbonic acid\/bicarbonate buffer in aqueous environment","format":"limited_html"}],"field_summary_sentence":[{"value":"Prof. Ehud Pines, Ben Gurion University"}],"uid":"27275","created_gmt":"2011-05-24 00:00:00","changed_gmt":"2016-10-08 01:50:45","author":"Shirley Tomes","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2011-06-07T17:00:00-04:00","event_time_end":"2011-06-07T18:00:00-04:00","event_time_end_last":"2011-06-07T18:00:00-04:00","gmt_time_start":"2011-06-07 21:00:00","gmt_time_end":"2011-06-07 22:00:00","gmt_time_end_last":"2011-06-07 22:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"85951","name":"School of Chemistry and Biochemistry"}],"categories":[],"keywords":[{"id":"89","name":"chemistry"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003EShirley Tomes\u003C\/strong\u003E\u003Cbr \/\u003EChemistry \u0026amp; Biochemistry\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=st81\u0022\u003EContact Shirley Tomes\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-0591\u003C\/strong\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}