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Selenium nucleic acids for nuclei acid structure and function studies
Published in Gary Bañuelos, Zhi-Qing Lin, Dongli Liang, Xue-bin Yin, Selenium Research for Environment and Human Health: Perspectives, Technologies and Advancements, 2019
V.G. Vandavasi, B. Hu, Y.Q. Chen, Q.W. Zhao, H.H. Liu, J.H. Gan, A. Kovalevsky, L. Hu, Z. Huang*
Room- and cryo-temperature X-ray data were collected on an in-house Rigaku HomeFlux system equipped with the R-AXIS IV++image plate detector, the Rigaku MicroMax-007 HF Cu rotating-anode generator, Osmic VariMax HR optics, and the Oxford CryoStream operating at 100K. Quasi-Laue neutron data to 2.0 Å resolution (room temperature) and to 1.9 Å resolution (100 K) were collected from the 0.4 and 0.2 mm3 DNA crystals, respectively (Vandavasi et al. 2018). During the neutron diffraction experiment, the crystal was held stationary at different ϕ settings for each exposure. In total, 22 diffraction images were collected (with an exposure time of 2 h per image) from 3 different crystal orientations for the room-temperature experiment.A total of 25 diffraction images (6 h per image) were collected for a crystal at 100K.
Clinical Radiographic Units
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
Scatter can be reduced in many ways. Tighter collimation reduces scatter and reduces patient dose, using beam restrictors such as lead cylinders, and lead diaphragms in the light beam diaphragm can help to restrict the beam. More commonly, the adjustable collimator in the light beam diaphragm is used to restrict the beam to its smallest size (Martin 2007). Reducing the patient thickness through compression can also reduce scatter. Some manufacturers designed systems with an option for automatic collimation to the image receptor. This means that the collimation of the X-ray beam can never be larger than the image plate or image receptor placed within the cassette holder. This ensures that the X-ray beam never extends beyond the area of the useful image. An alternative to automatic beam collimation is for the radiographer to collimate to the detector size before the detector is placed underneath the table, and then either not adjust the collimation or make it smaller, as appropriate.
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
Grazing incidence X-ray diffraction (GIXRD) is a surface-sensitive technique providing phase compositions, crystalline-phase purity, crystallographic information, structural ordering, and crystallite orientation of chemicals in the forms of thin films, coatings, and membranes. In GIXRD setup, the incident monochromatic X-ray beam is parallelly exposed to the surface (or interface) of a sample at the very-small (grazing) incidence angle (αi), which consequently interacts with the material only at a low depth profile but with a wide footprint (i.e., surface probing). The diffracted (also called Bragg scattered) X-ray is detected by a position-sensitive detector (PSD), mainly using area detectors such as X-ray image plate and CCD detector.
Restart of the Transient Reactor Test (TREAT) Facility Neutron Radiography Program
Published in Nuclear Technology, 2019
Shawn R. Jensen, Aaron E. Craft, Glen C. Papaioannou, Wyatt W. Empie, Blaine R. Ward, Lee A. Batt
Conventional X-ray radiography utilizes a direct method to obtain radiographs. The direct method involves an X-ray or gamma source passing X-rays or gamma radiation though the specimen directly onto film, a photostimulable phosphor (PSP) plate (image plate), or a digital imaging system. When imaging radioactive items, the direct method will not produce a quality radiograph due to the high gamma radiation background emitted by the radioactive object. To obtain radiographs of radioactive items, TREAT utilizes indirect, or transfer method, radiography.