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Materials Characterization Using Advanced Synchrotron Radiation Techniques for Antimicrobial Materials
Published in Peerawatt Nunthavarawong, Sanjay Mavinkere Rangappa, Suchart Siengchin, Mathew Thoppil-Mathew, Antimicrobial and Antiviral Materials, 2022
Chatree Saiyasombat, Prae Cbirawatkul, Suittipong Wannapaiboon, Catleya Rojviriya, Siriwat Soontaranon, Nuntaporn Kamonsutthipaijit, Sirinart Chio-Srichan, Chanan Euaruksakul, Nichada Jearanaikoon
SR microtomography beamline in most synchrotron facilities usually consists of a specimen rotator, single-crystal scintillator (X-ray phosphor), optical lens, and an area detector such as a CCD. Depicted in Figure 7.7, the polychromatic X-rays generated from a bending magnet or an insertion device (an undulator or a multipole wiggler) are converted to a monochromatic beam by a double-crystal monochromator (DCM) or a double-multilayer monochromator (DMM). When the monochromatic X-ray beam passes through a specimen mounted on the rotation stage, the X-rays are attenuated due to interactions with the electrons in the specimen. A detection system records the attenuated X-ray beam. It is converted into visible light by a scintillator, then collected and magnified by an objective lens, and forms a real-space image on the area detector.
Neutron Imaging
Published in Maria L. Calvo, Ramón Fernandez Álvarez-Estrada, Advances in Neutron Optics, 2019
The mosaicity has to be selected to enable the envisaged resolution, which however is wavelength dependent. It has to be considered that mosaicities larger than the beam divergence do relax the wavelength resolution, but do not increase the flux density, but the perpendicular beam size. Finally, the crystal monochromator arrangements also contaminate longer wavelengths with shorter wavelength second-order reflections. These can be filtered either by an additional crystal or through preconditioning the beam, e.g., with a velocity selector.
Visualizing local bending of lattice planes by extending two-azimuth synchrotron X-ray diffraction datasets to asymmetric reflection
Published in Science and Technology of Advanced Materials: Methods, 2023
We obtained diffracted intensity images in a reflection mode at the beamline BL20B2, SPring-8, Japan. The maximum X-ray beam size was approximately 300 mm in the horizontal direction and approximately 20 mm in the vertical direction, which was defined by monitoring with a two dimensional X-ray detector. The slit opening in front of the sample was adjusted according to the sample size so that the sample was fully bathed in the X-ray beams. The wavelength of the incident X rays used was approximately 1.3 Å as selected by a Si (111) double-crystal monochromator. The incident X-ray beam was highly parallel in the vertical direction with a calculated angular divergence of approximately 29.8 rad. A flat-panel sensor (FPS) detector (C7942, Hamamatsu Photonics) with a pixel size of 50 × 50 m2 and a resolution of 2368 × 2240 was used for the image acquisition. The detector was installed parallel to the sample. Table 1 lists the typical measurement parameters of the experimental setup.
X-ray absorption study of oxide film formed on Alloy 600 in PWR primary water at 290°C with a decreased concentration of dissolved hydrogen
Published in Journal of Nuclear Science and Technology, 2023
Kenta Kakitani, Takaaki Kobayashi, Hiroaki Abe
Two samples of the oxide film formed on the inner surface of the half-tubes of Alloy 600 in the condition of 5 and 30 ml/kg DH were characterized by the XAFS measurement. The XAFS spectra at the Fe K-edge were acquired at the SPring-8 BL08B2 beamline (Hyogo, Japan) at room temperature. The synchrotron radiation from a bending magnet was monochromatized with a Si (111) double-crystal monochromator. The energy of the incident beam was calibrated with the Fe K-edge of an iron foil. As a preliminary test, we conducted XAFS measurements in the fluorescence mode, but the obtained XAFS spectra mainly reflected information about the base alloy and could not characterize the surface oxide film. Therefore, we chose to perform XAFS measurements in the conversion electron yield (CEY) mode because this mode is a surface-sensitive technique and appropriate for the characterization of the surface oxide film [16]. In the CEY mode (Figure 1), a sample is placed in a cell filled with He gas at atmospheric pressure and irradiated with the synchrotron X-ray. Electrons emitted from the surface of the irradiated sample ionize He. The He ions or electrons can be collected by an electrode with a bias voltage. The measured electric current is in proportion to the X-ray absorption intensity of the specimen.
Conceptual design of a simple small angle X-ray scattering (SAXS) beamline
Published in Instrumentation Science & Technology, 2021
Zhihong Li, Quanjie Jia, Ming Li
A conceptual design of a simple but powerful SAXS beamline with a quasi-monochromatic X-ray from an in-air undulator as incident pink beam at HEPS is presented. It provides real-time (µs to ms) and wide spatial (Å to µm) observation of structural change in matter by SAXS and WAXS in transmission and grazing incidence modes except for anomalous scattering. The design gives full play to the superiorities of the HEPS in high energy and low emittance, combines classic and new technologies, and makes the structure of the beamline as simple as possible while meeting the requirements of most experiments. The key idea of the design is to directly use the sharp fundamental radiation of undulator as a quasi-monochromatic X-ray pink beam which is deflected, collimated, and then used for experiments. No crystal monochromator is necessary based on the quasi-monochromatic properties of the pink beam. Also, no focusing mirror is used in view of the beam properties with small size and divergence. By optimizing the undulator, deflector, collimation system, and camera, the derived circular beam with low background is suitable for most experiments. The beamline has several advantages including simple beamline structure, high stability, wide flux range, low background, easy operability, and low construction and maintenance costs. This beamline has huge potential application in many fields of science and industry.