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Single crystal aluminum and copper of (001) and (110) orientation were shock peened using laser beam of 12 micron diameter and observed with X-ray micro-diffraction techniques based on a synchrotron light source. The X-ray micro-diffraction affords micron level resolution as compared with conventional X-ray diffraction which has only mm level resolution.(More)
I. INTRODUCTION OLLOWING a radiological event there will be a need for mass triage requiring analysis of tens to hundreds of thousands of samples. An example of this is the incident at Goiânia, Brazil [1] in 1987. In the first few days after the incident became known, about 130,000 people, out of the 1.3 million inhabitants of Goiânia arrived at screening(More)
Electron backscatter diffraction (EBSD) is used to investigate crystal lattice rotation caused by plastic deformation during high-strain rate laser shock peening in single crystal aluminum and copper sample on ͑11 ¯ 0͒ and (001) surfaces. New experimental meth-odologies are employed which enable measurement of the in-plane lattice rotation under approximate(More)
The immunofluorescence-based detection of γ-H2AX is a reliable and sensitive method for quantitatively measuring DNA double-strand breaks (DSBs) in irradiated samples. Since H2AX phosphorylation is highly linear with radiation dose, this well-established biomarker is in current use in radiation biodosimetry. At the Center for High-Throughput Minimally(More)
Laser shock peening (LSP) is a process to improve material fatigue life by introducing compressive residual surface stress in a target. The residual stresses are introduced when a high-intensity laser impinges on an ablative layer deposited on the surface of the target material. The interaction between laser and the ablative layer creates a high pressure(More)
Laser forming of steel is a hot forming process with high heating and cooling rate, during which strain hardening, dynamic recrystallization, and phase transformation take place. Numerical models considering strain rate and temperature effects only usually give unsatisfactory results when applied to multiscan laser forming operations. This is mainly due to(More)
The technologically important case of reactive gas laser cutting is examined. A transient two-dimensional (2D) model is developed specifically to investigate the effect of various CNC velocity profiles on the resulting cutting front temperature. Coordinated motion systems must ramp up and down to their target speeds, and therefore such accelerations must be(More)
A completely automated, high-throughput biodosimetry workstation has been developed by the Center for Minimally Invasive Radiation Biodosimetry at Columbia University over the past few years. To process patients' blood samples safely and reliably presents a significant challenge in the development of this biodosimetry tool. In this paper, automated failure(More)