|Fundamentals and Applications of Aerosol Spectroscopy|
|Wednesday, 09 March 2011 16:36|
The book Fundamentals and Applications of Aerosol Spectroscopy, recently published by Taylor and Francis Books, Inc., boasts two chapters in the "UV, X-Ray, and Electron Beam Studies" section written by Berkeley Lab researchers, highlighting a significant amount of work completed at the ALS.
Chapter 17: Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research
Ryan C. Moffet, Alexei V. Tivanski, and Mary K. Gilles – ALS BL 11.0.2/ 5.3.2
Scanning transmission x-ray microscopy (STXM) combines x-ray microscopy and near edge x-ray absorption fine structure spectroscopy (NEXAFS), providing spatially resolved bonding and oxidation state information. This chapter focuses on its applications to atmospheric aerosols; beginning with an introduction to STXM/NEXAFS in a manner approachable to non-experts, the chapter continues by providing a survey of STXM/NEXAFS aerosol studies.
One reason to use STXM/NEXAFS on aerosol samples is to examine the spatial distribution of different types of carbon within a particle. For example, soot’s absorption of solar radiation can be enhanced by an organic carbon coating. Hence, how soot and organics are mixed within individual aerosols is directly relevant for studying global climate change. Other research focuses on how sulfur is partitioned between different types of aerosols, the oxidation states of iron (important for its bioavailability), and the identification of metallic species.
Chapter 17 illustrates the current range and recent growth of scientific investigations employing STXM/NEXAFS to probe atmospheric aerosol composition, morphology, surface coatings, mixing states, and atmospheric processing, and to indicate directions for future research.
Chapter 15: Aerosol Photoemission
Kevin Wilson, Musahid Ahmed and Hendrik Bluhm – ALS BL 9.0.2
This chapter provides an introduction to the application of photoelectron spectroscopy in aerosol science. During photoelectron spectroscopy, a surface sensitive probe of chemical composition is applied to aerosols, yielding valuable information about the surface chemistry and physics of nanoparticles. This can have important implications for problems ranging from cloud chemistry to interstellar dust grains. More fundamentally, the authors discuss how simple changes in a particle’s charge state produced by the absorption of ionizing radiation can be used to sensitively probe aerosol desorption kinetics, surface polarization energy and solvation, and nanoparticle circular dichroism. Much of the authors’ work at the Advanced Light Source is included in this chapter, combining synchrotron radiation with aerosol beams or droplet trains, finding new ways to examine solvation at simple liquid surfaces, calculating the polarization energy of bio-aerosols, and studying how photoemission patterns are controlled by nanoparticle size.