Chemical kinetics in submicron droplets
                            Opportunity                                                                                 ALS-U Tools Required
     Submicron droplets are reactive compartments                                                       Soft x-ray imaging/spectroscopy beamline with 
     whose overall chemistry is governed by                                                             ~1 mm focal spot (possibly nanofocus); flexible 
     interplay of surface and bulk processes.  There is                                                 sample environment (temperature, humidity); 
     emerging evidence that confined reactions                                                          colliding aerosol droplet jets for rapid mixing 
     proceed via much different mechanisms and                                                          and sub-ms chemical kinetic measurements; 
     rates than the same reactions in macroscopic                                                       optical and electrostatic aerosol traps 
     containers.
                    Importance of ALS-U                                                                               Broader Scientific Impact
     The coherence of ALS-U will enable soft x-ray                                                      Aerosol chemistry is one of the more poorly 
     microscopy, correlation spectroscopy, and                                                          modeled feature of earth’s climate system;  
     nanoprobe spectroscopies to probe chemical                                                         droplets replicate complex chemistry relevant 
     structure and kinetics with nanoscale sensitivity.                                                 to many realistic environments, e.g., geological 
     References:                                                                                        pores, atmospheric aerosols, micelles, etc.
     Carroll, B.; Hidrovo, C., Experimental Investigation of Inertial Mixing in Colliding Droplets. Heat 
         Transfer Engineering 2013, 34, (2-3), 120-130.
     Lee, J. K.; Kim, S.; Nam, H. G.; Zare, R. N., Microdroplet fusion mass spectrometry for fast reaction 
         kinetics. Proceedings of the National Academy of Sciences 2015, 112, (13), 3898-3903.
     IPCC, Climate Change: The Physical Science Basis - Contribution of Working Group I to the Fourth 
         Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University                 Contact: Kevin Wilson, LBNL/CSD 
         Press: Cambridge, 2007.
      
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