Registration & Abstracts


Practical Matters




Agenda confirmed 4.14


Workshop 9

Thursday, May 4
Bldg. 402, Lecture Hall
8:30 - 12:10
1:30 - ~6:00 (open)

X-ray Spectromicroscopy: A Tool for Environmental Science?

Juergen Thieme, Institute for X-Ray Physics, University of Goettingen, Goettingen, Germany
Ian McNulty, APS, Argonne National Laboratory, Argonne, USA
David Paterson, Australian Synchrotron, Melbourne, Australia
Stefan Vogt, APS, Argonne National Laboratory, Argonne, USA

To Agenda >

Environmental science is an extremely diverse field impacting many facets of science, technology, industry, and everyday life. Because of the complexity of environmental processes and the many mutual interactions involved, competence is required in more than one area of expertise and a multidisciplinary approach is often necessary to understand them. Experts in geochemistry, hydrology, microbiology, atmospheric, and soil sciences, to name a few, are essential in this regard. For example, the complex roles of carbon, nitrogen, phosphorus, and sulfur cycles in the environment are incompletely understood, not to mention their mutual interactions. Similarly, our knowledge of uptake and metabolism of trace metals by biological organisms, and their influence on the environment, is far from complete. Elemental transport, redox processes, microbial activity, and anthropogenic influences all affect these processes. Knowledge of each individual piece of the puzzle contributes to a better understanding of the overall picture. X-ray spectromicroscopy is a powerful tool for addressing key questions in the environmental sciences because of its high spectral and spatial resolution. This combination of high-resolution microscopy with spectroscopic capabilities allows determination of elemental composition as well as chemical speciation and identification of trace elements on length scales extending to the nanoscale. X-ray spectromicroscopy has already been applied to a very diverse range of problems in a multitude of scientific areas. It is now timely to define the most important problems and research directions in environmental science for which the latest x-ray spectromicroscopy methods would be indispensable and have the greatest impact.

The aim of this workshop is to bring together experts in all fields of the environmental sciences to formulate and discuss these key issues. A secondary aim is to improve accessibility to these methods to researchers in these fields. The workshop scope is limited to x-ray energies ranging from the K-absorption edge of carbon around 0.28 keV to that of iron around 7.2 keV and to spatial dimensions on the scale of a few microns extending to the nanoscale. This energy range covers many environmentally important elements and the working ranges of existing and planned x-ray microscopes with spectroscopic capabilities. This size range is where the behavior of particles such as colloids are determined not by their bulk properties but by their surfaces, and where the interface between local chemistry and macroscopic processes often occurs. The expected impact of this workshop is, however, much broader: a clear definition of outstanding problems in environmental science could serve as a roadmap for research activities worldwide.

Confirmed agenda as of April 14, 2006

8:30 Welcome

Introductory remarks
Juergen Thieme, Institute for X-ray Physics, University of Goettingen, Germany

9:00 Probing Structures and Processes in Soil Chemistry using X-ray Spectromicroscopy
Dean Hesterberg, North Carolina State University
9:30 Molecules, Cells and Organisms: Environmental Spectromicroscopy of Biological Systems
Ingrid Pickering, Dept. of Geological Sciences, University of Saskatchewan, Canada

Formation of Minerals Inside and Near Single Bacterial Cells: Elemental Content and Valence State at the Sub-Micron Scale
Maxim Boyanov, Biosciences Division, Argonne National Laboratory

10:20 Break, Atrium and Gallery
10:50 X-ray Spectromicroscopy: A Tool for Advanced Understanding of Aqueous Colloidal Systems
Laurent Michot, Laboratoire Environnement et Minéralurgie, Nancy, France
11:20 Scanning Transmission X-ray Microscopy of Actinide Materials
David Shuh, Chemical Sciences Division, Lawrence Berkeley National Laboratory
11:50 Spectromicroscopy Analysis of Spore-Forming Bacteria
Bjorg Larson, Dept. of Physics & CEMS, SUNY Stony Brook
12:10 Lunch
Bldg. 402, Lower Level, Tent

Anaerobic Geomicrobial Effects on the Fate and Transport of Heavy Metals and Radionuclides
John Coates, Dept. of Plant and Microbial Biology, University of California, Berkeley

14:00 Metal Cycles
Satish Myneni, Dept. of Geosciences, Princeton University (tentative)
14:30 Ocean Phosphorus Cycling: New Insights from X-ray Spectromicroscopy
Ellery Ingall, School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta
14:50 Break, Atrium and Gallery
15:20 Spectromicroscopy in the 1–4 keV Region: New Opportunities for Environmental Science
David Paterson, Australian Synchrotron, Melbourne, Australia
15:50 Colloidal Structures from the Environment Explored by X-ray Spectromicroscopy
Juergen Thieme, Institute for X-ray Physics, University of Goettingen, Germany

Break, Atrium and Gallery


Imaging Trace Metals in Biological Systems with Hard X-Ray Fluorescence Microscopy
Stefan Vogt, X-ray Science Division, Argonne National Laboratory

17:00 Spectral Deconvolution of Full-Spectral SXRF Imaging Data Aimed at Real-Time Quantitative Imaging Using the X-ray Fluorescence Microprobe
Chris Ryan, CSIRO Exploration and Mining, Clayton, Australia
17:20 Open discussion
Ian McNulty, Argonne National Laboratory