by Kathy Chambers 19 Nov, 2014 in
Every summer for the past 16 years, the Department of Energy has invited the best and brightest graduates from across the country to attend the National School on Neutron and X-ray Scattering (NXS). This year, 65 graduate students attending North American universities, and studying physics, chemistry, materials science, or related fields, participated in the 14-day whirlwind emersion into national user facilities to learn in a hands-on environment how to use neutrons and X-rays in their research. This educational program is jointly conducted by Argonne National Laboratory's Advanced Photon Source and Materials Science Division and Oak Ridge National Laboratory's Neutron Scattering Science Division.
Every material’s physical and chemical properties are determined by how the atoms of its different chemical elements are bound together and arranged. X-ray scattering has been used to gather clues about materials’ atomic structures for about a century. Once reactors were built that could provide intense neutron beams, researchers began to use scattered neutron beams to more clearly see different aspects of the atomic structures. These scattering experiments have produced important developments in preventing hydrocarbon deposits in automobile engines, in improving manufacturing techniques to make products stronger, in developing antiviral compounds, and in the search for superconductors.
The scope of the NXS educational program is immense. The DOE Office of Science’s...
Related Topics: Advanced Photon Source, Argonne National Laboratory, High Flux Isotope Reactor, National School on Neutron and X-ray Scattering (NXS), neutron scattering, NXS, Oak Ridge National Laboratory, Spallation Neutron Source, x-ray scatteringRead more...
During the 1700’s, the Reverend Thomas Bayes was a nonconformist minister at the Mount Sion Chapel in Tunbridge Wells, UK, about 40 miles southeast of central London. Having studied both theology and logic at the University of Edinburgh, he was also a mathematician and developed a strong interest in probability late in life. He was known to have published only one book on theology and one book on mathematics in his lifetime. A third manuscript he never published about the probability of cause made him famous. After his death, a good friend Richard Price recognized the importance of the paper and, after extensive editing, submitted it for publication. More than 20 years later, the great French mathematician, Pierre-Simon Laplace devised the formula for Bayes’ probability of causes and acknowledged Bayes as the discoverer of what we now know as Bayesian inference.
This year is the 250th anniversary of Bayesian inference. During its history, the Bayes theory has been doubted, disproven, defended, and challenged again and again and again. It has consistently been an important tool in understanding what we really know, given the evidence and other information we have. It helps incorporate "conditional probabilities" into our conclusions.
Bayesian inference has recently become prominent in many scientific fields due to the availability of simulation-based computational tools for implementation. Researchers at Los Alamos National Laboratory are using Bayes’ theorem to deduce structures of crystals and determine macromolecular structures. The Lawrence Livermore National Laboratory describes how a sequential Bayesian processor would be used to assess...Read more...