Narrow Results

The following sections are included:

• Introduction

• Basic Approaches
  • Synchrotron X-ray Production
  • X-ray Cross Sections
  • Synchrotron Radiation Induced X-ray Emission (SRIXE)
  • Extended X-ray Absorption Fine Structure (EXAFS) and Extended X-ray Absorption Near Edge Structure (XANES)
  • Computed Microtomography (CMT)
  • Sample Radiation Damage Effects

• Applications
  • Biological Applications
    • Reversible Effect of Low Lead Levels on Neuronal Growth
    • Analysis of Zinc Binding Capabilities of a Protein Domain
    • Stroke and Calcium Concentrations in the Brain
    • Studies of Bone and Cartilage
  • Geological and Extraterrestrial Materials
    • Microstructure of Shock-recovered Berea Sandstone
    • Internal Structure of Two Type-I Deep Sea Spheres by X-ray Computed Microtomography
    • Hydrothermal Vents
    • Investigation of New York/New Jersey Harbor Dredged Material
  • Environmental Chemistry
    • Secondary Ion Mass Spectroscopy and Synchrotron X-ray Fluorescence in the Study of the Qualitative Variation in Metal Content with Time in Tree Rings
  • Materials Analysis
    • Thermal Spray
    • Study of Supported Catalysts
    • Investigation of Integrated Circuit Structures Using CMT and Microdiffraction

• Summary

• Acknowledgments

• References

Ocean cold water mass is an oceanographic phenomena that oceanographers concerned many years. Method of monitoring the cold water mass is a problem to be solved urgently. A new tomography approach, modal wave-number tomography (MWNT), is proposed for monitoring the cold water mass and numerical simulation is carried out for Yellow sea cold water mass. The perturbation theory is used to invert the coefficients of empirical orthogonal functions of sound speed profile (SSP) from the local modal wave number perturbation. The numerical simulation shows that the modal wave number tomography can invert average SSP, in particular, is of potential to monitoring range dependent SSP structure.

Recent advances in the technique of terahertz time-domain spectroscopy have led to the development of the first fiber-coupled room-temperature broadband terahertz sources and detectors. The fiber coupling permits the repositioning of the emitter and receiver antennas without loss of temporal calibration or alignment, thus enabling multistatic imaging. We describe a new imaging method which exploits this new capability. This technique emulates the data collection and image processing procedures developed for geophysical prospecting. We use a migration procedure to solve the inverse problem; this permits us to reconstruct the location, shape, and refractive index of targets. We show examples for both metallic and dielectric model targets, and we perform velocity analysis on dielectric targets to estimate the refractive indices of imaged components. These results broaden the capabilities of terahertz imaging systems, and also demonstrate the viability of the THz system as a test bed for the exploration of new seismic processing methods.

X-ray free-electron lasers provide a greatly increased peak intensity on femtosecond time scales, opening up new opportunities to study the structure and dynamics of nanoparticles, viruses and biological macromolecules. These opportunities are being realized with new crystallography techniques to study nanoscale periodic samples and with coherent diffractive imaging techniques to study non-periodic samples. This chapter provides an introduction to coherent diffractive imaging techniques, a review of its applications and development at synchrotron sources, and finally a survey of the first imaging and crystallography results from X-ray laser experiments.

Particle beam radiography, which uses a variety of particle probes (neutrons, protons, electrons, gammas and potentially other particles) to study the structure of materials and objects noninvasively, is reviewed, largely from an accelerator perspective, although the use of cosmic rays (mainly muons but potentially also high-energy neutrinos) is briefly reviewed. Tomography is a form of radiography which uses multiple views to reconstruct a three-dimensional density map of an object. There is a very wide range of applications of radiography and tomography, from medicine to engineering and security, and advances in instrumentation, specifically the development of electronic detectors, allow rapid analysis of the resultant radiographs. Flash radiography is a diagnostic technique for large high-explosive-driven hydrodynamic experiments that is used at many laboratories. The bremsstrahlung radiation pulse from an intense relativistic electron beam incident onto a high-Z target is the source of these radiographs. The challenge is to provide radiation sources intense enough to penetrate hundreds of g/cm² of material, in pulses short enough to stop the motion of high-speed hydrodynamic shocks, and with source spots small enough to resolve fine details. The challenge has been met with a wide variety of accelerator technologies, including pulsed-power-driven diodes, air-core pulsed betatrons and high-current linear induction accelerators. Accelerator technology has also evolved to accommodate the experimenters' continuing quest for multiple images in time and space. Linear induction accelerators have had a major role in these advances, especially in providing multiple-time radiographs of the largest hydrodynamic experiments.