journal menu
issue contents
July 2016 issue
Cover illustration: High-energy X-ray Bragg coherent diffraction imaging study of the (111) diffraction of nanocrystals in FePt and AuPd silica nanocomposites (see Monteforte, Estandarte, Chen, Harder, Huang and Robinson, pages 953-958). The central Bragg diffraction frames of the FePt (top) and AuPd (bottom) nanocrystals are shown, along with their corresponding 3D reconstructions with morphology and strain isosurface.
facility information
research papers
An X-ray mirror mechanical bender is characterized. The device is measured using a Fizeau large-aperture interferometer, and the most important effects, such as hysteresis, twisting, reproducibility and stability are investigated. The mirror silicon substrate is 950 mm long and the system is a possible candidate for the `adjustable' mirror element foreseen in the optical setup of the European XFEL beam transport.
An optimization of the undulator layout of X-ray free-electron laser facilities based on installing small chicanes in the space between the undulator modules is presented. The chicanes allow the saturation length to be reduced, the brightness to be increased and very short and high-power pulses to be generated.
A new design for an undulator beamline of free-electron-laser facilities is presented to provide two FEL pulses with different photon energies where an electron beam is tilted, injected into the beamline and delayed in the middle by a chicane to control the time separation. This scheme will be implemented at the soft X-ray beamline at SwissFEL with a tuning range in photon energy of 500% and a pulse separation up to 1 ps.
Open 
access
access
A novel, flexible yet simple method to generate gigawatt X-ray free-electron-laser radiation with unprecedented spectral bandwidth above the 10% level is presented. Such broadband radiation will improve substantially the efficiency of techniques like X-ray crystallography and spectroscopy, paving the way for outstanding progress in fields like biology and material science.
A dispersive analyzer system using an assembly of multiple flat crystals provides a way of overcoming an intrinsic energy-resolution limit of diced spherical crystal analyzers, commonly used in resonant inelastic X-ray scattering instruments. However, in order to achieve a sufficiently large angular acceptance for collecting scattered radiation, a collimating element is required. For this purpose, a laterally graded, parabolic, multilayer Montel mirror was designed for use at the Ir L3-absorption edge. Its characterization and performance are reported here.
A VUV absorption spectroscopy branch has been developed upon a Fourier transform spectrometer; the general performances are described.
An X-ray fluorescence flow cytometer capable of performing single-cell metal analysis is described and developed. This device is capable of detecting mM to µM concentrations from sample volumes as small as ∼50 fL.
An integrated continuous-scan system has been developed at the Stanford Synchrotron Radiation Lightsource (SSRL). The time efficiency and repeatability of the continuous-scan system were tested using X-ray diffraction from a ZnO powder and compared with the step-scan technique.
For the first time the third-order nonlinear time-dependent Takagi's equations of X-rays in crystals are obtained. The third-order nonlinear and linear time-dependent dynamical diffraction of X-rays spatially restricted in the diffraction plane pulses in crystals is investigated. The results of analytical and numerical calculations are presented.
Open access
access
The feasibility for multi-speckle XPCS measurements in the ultra-low-angle range is demonstrated. The performance of the setup is illustrated by means of colloidal dynamics.
Concentrations and distributions of Br, Ca, Cl, Cr, Cu, K, Fe, Mn, Pb, Ti, V and Zn in Phragmites australis root system are investigated with micrometer-scale resolution in order to understand the chemical mechanisms of metal uptake by plants and the transport pathways in the plants.
Full multiple scattering (FMS) theory is used to simulate vanadium K-edge X-ray absorption near-edge spectra for a variety of V model compounds. The data shown here highlight the correlation between FMS non-structural parameters and the V coordination geometry and oxidation state.
The feasibility of a novel one-step `drop-cast' stabilization method as a prompt and efficient approach to extend the accessible size regime of the Bragg coherent diffraction imaging (BCDI) technique is demonstrated. Fine chemically synthesized nanocrystals with dimensions sub-100 nm were stabilized and from BCDI measurements three-dimensional reconstructions of the nanocrystals were achieved.
Synchronous digitization, in which an optical sensor is probed synchronously with the firing of an ultrafast laser, was integrated into an optical imaging station for macromolecular crystal positioning prior to synchrotron X-ray diffraction. Using the synchronous digitization instrument, second-harmonic generation, two-photon-excited fluorescence, one-photon-excited fluorescence, two-photon-excited ultraviolet fluorescence and bright field by laser transmittance were all acquired with perfect image registry at up to video rate (15 frames s−1).
Both phase- and attenuation-contrast tomographic imaging-based synchrotron radiation can be used to visualize the physiological arrangement of the entire intramedullary artery network in the mouse spinal cord at a high resolution level. Compared with attenuation-contrast imaging, phase-contrast imaging allows vessel visualization without contrast agent injection and is expected to be a reliable method for intramedullary artery detection.
Open access
access
Detailed procedures and key points in preparing frozen-hydrated biological specimens are reported for efficient cryogenic coherent X-ray diffraction imaging using an X-ray free-electron laser.
The X-ray nanotomography technique was compared with scanning electron microscopy for quantitative three-dimensional analysis of nanocomposite particles.
Open access
access
Performance models for tomographic reconstruction workflows are presented. A workflow management system is implemented for evaluation of the proposed models on geographically distributed resources.
Synchrotron X-ray tomography has been applied to the study of titanium parts fabricated by additive manufacturing. Samples were chosen to examine the effect of build direction and complexity of design on the surface morphology and final dimensions of the piece.
Synchrotron X-ray tomography has been applied to the study of defects within three-dimensional printed titanium parts. This has revealed a number of defects which may not otherwise have been seen, the location and nature of which can contribute to understanding the interplay between design and manufacturing strategy.
Phase measurement in hard X-ray phase shifting digital holography is demonstrated.
short communications
A new rig developed to study time-lapse deformation of solid samples using in situ microtomography (up to 250°C and 1000 bar) is described.
beamlines
Design and testing results of a vacuum ultraviolet beamline and three endstations for combustion chemistry studies at National Synchrotron Radiation Laboratory in Hefei, China, are reported.
computer programs
Open access
access
Software to analyze polychromatic diffraction patterns from polycrystalline samples is described.
current events
Free
