Dr. Alex Hexemer 、Dr. Cheng Wang 学术报告2017-06-26 15:50:51
个人简介：Alexander Hexemer在加州大学圣芭芭拉分校获得材料学博士学位后即加入美国先进光源进行博士后研究工作，主要从事广角及小角X射线衍射线站的发展及维护。2006年Alexander Hexemer获劳伦斯伯克利国家实验室杰出表现奖。2007年成为美国先进光源束线7.3.3研究员，参与发表论文103篇，引用两千余次。
摘要：Towards Real-Time Analysis of Morphologies using Scattering
The Advanced Light Source (ALS) is 3rd generation synchrotron with 40 different beamline. The ALS produces an estimate of 2 Petabytes of raw and complex data. The increase in data is a result of higher brightness of the synchrotron, faster detectors and a stronger and stronger focus on in-situ and in-operando experiments .Over the last few years we have developed a variety of solutions to address these data challenges for X-rays. Due to the complexity and the size of the challenge, it was essential to combine the knowledge of different science disciplines to create what is commonly now called a SuperFacility. The SuperFacility combines the knowledge and expertise of a synchrotron, mathematics and algorithms, high speed networking, high performance computing and data movement. We will highlight the path of data at the ALS, from creation to curation and the current analysis tools available for X-ray scattering to address large data. The main goal of our work is to provide scientists at synchrotrons with tools to focus on their science and not be slowed down by a data deluge.
摘要：Multimodal Resonant X-ray Scattering for Energy Materials
Recent development of resonant soft x-ray scattering (RSoXS) at the Advanced Light Source (ALS) has enabled its applications to many critical research areas of materials research. Combining conventional x-ray scattering with soft x-ray absorption spectroscopy, RSoXS is a unique chemical sensitive structure probe that provides a novel route to unambiguously decipher the complex morphologies of mesoscale materials. Tuning x-ray photon energies to match the absorption spectrum of the different chemical components, the scattering contributions from the different components can be selectively enhanced, enabling a glimpse into these complex morphologies with unprecedented details. Applications of RSoXS have been extended to the areas of structured polymer assemblies, organic electronics, functional nano-composites, as well as liquid crystals. The overarching challenge now across various disciplines is to investigate the interfacial phenomenon of new and complex materials in their operational conditions, including batteries, catalysts, gas separations, fuel cells and water desalination, and bio-hybrid systems. In order to achieve comprehensive understanding of the in-operando process, we need multimodal research tools that provide information from different perspectives in order to discover, understand, and control the interfacial phenomena and architectures. This will require combining different in situ probes, such as x-ray scattering and electron microscopy, simultaneously in the same operating condition. We will discuss the recent development of customized instrumentation, multimodal characterization methods, as well as comprehensive theory for the extraction of the chemical distribution and spatial arrangement at multiple length scales in the application of energy materials.