Fluorescence imaging at the MacCHESS A1 and F1 beamlines makes crystal centering easier
And, the tiny beam has to hit the tiny crystal. The location of the beam can be well determined and doesn't change, but how do we know where the crystal is?
And, the tiny beam has to hit the tiny crystal. The location of the beam can be well determined and doesn't change, but how do we know where the crystal is?
SABIC recently instituted this award to spur and acknowledge innovation in scientific and engineering fields contributing to the advancement of chemical engineering. Purdum is the first author on the paper "Understanding Polymorph Transformations in Core-Chlorinated Naphthalene Diimides and their Impact on Thin-Film Transistor Performance," published recently in Advanced Functional Materials [1].
Their paper - “High Dynamic Range Pixel Array Detector for Scanning Transmission Electron Microscopy” - discusses the transfer of their popular x-ray detector technology into the environment of the electron microscope [1]. Pixel Array Detectors, or PADs, have brought outstanding new capabilities to x-ray instruments, such as in-pixel circuitry providing a 1,000,000:1 dynamic range within a single frame and 1.1 kHz framing rate enabling rapid data collection.
Dr. Georg Hoffstaetter, former head of the SRF group, will now become Cornell’s Principal Investigator for C-BETA (Cornell-Brookhaven ERL Test Accelerator).
The day included talks by Peter Wittich, on his past work at the Sudbury Neutrino Observatory, and Julia Thom-Levy, on the CERN particle accelerator. Both are Cornell associate professors of physics who co-sponsored the event through funding from the Particle Physics at the Energy Frontier Award #1307256, from the National Science Foundation. Research Assistant Professor Ryan Fisher, from Syracuse University, also presented on the recent news of the first observation of gravitational waves and on his work with Advanced LIGO.
A joint team of scientists from the Cornell High Energy Synchrotron Source (CHESS), King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, and Stanford University just reported an experimental break-through for studying the structural evolution of organic transistor layers during the coating process in-situ and in real-time with x-ray scattering.
Organic field-effect transistors (OFETs) find multiple applications, for instance as switches in active displays, radio frequency identification tags, or flexible biomedical sensors. The mobility of an organic semiconductor film is a measure for the velocity of charge carrier transport and is reflected in the operational speed of the device. Normally, the single crystal of an organic semiconductor achieves higher mobility than a thin film by several orders of magnitude, but would be hard to implement in solution-based production processes.
The signals look much like x-ray absorption near-edge spectroscopy (XANES), but the element K-edges (EK) are not otherwise accessible at CHESS. XRS offers possibilities for monitoring light element chemical and physical processes when soft x-rays cannot be used, for example samples at high pressure or during chemical processing. Analyzer crystals are positioned to collect and reflect scattered hard x-ray photons at energy E1 as incident beam energy E0 is scanned in the vicinity of E1+ EK.
There are four known families of membrane-immersed proteases (enzymes which break protein chains); all four carry out important functions and damage to them is implicated in pathologies including cancer, Parkinson's disease, impaired resistance to parasites, and more. When a mutation results in overactivity of a membrane protease, an inhibitor of the protease can be effective treatment for a disease. Designing such inhibitors has proven difficult, largely because of incomplete understanding of the catalytic process in the intramembrane environment.
This question was posed to several engineers at CHESS who were asked to describe in simple terms the three most important aspects of their jobs at a National Synchrotron Light-Source facility. Their responses were strikingly similar, with the ability to solve complex problems being at the top of their collective list, followed by the application of math and science knowledge to help them tackle these problems.