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Radiography and Computed Tomography for Works of Art
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
Maria Pia Morigi, Franco Casali
Synchrotron radiation is generated by large equipment where ultra-relativistic charged particles, usually electrons, are guided along circular orbits by magnetic fields. The emitted radiation has a very high intensity, which is orders of magnitude greater than that produced by X-ray tubes (allowing for fast measurements), and characteristic polarization properties (linear and circular), while the associated frequency can range over a wide portion of the electromagnetic spectrum, from infra-red (IR) to hard X-rays. The high flux makes it possible to use monochromators to select some specific energy bands of photons, while maintaining a sufficient flux for imaging. In this way, it is possible to fine-tune X-ray energy to the characteristics of the specimen and to obtain tomographic images unaffected by the so-called beam hardening artifacts, which are of much better quality than those obtained using conventional sources. In addition, the high spatial coherence of the X-ray beam makes phase-contrast imaging possible.
Use of radiochromic film with synchrotron radiation
Published in Indra J. Das, Radiochromic Film, 2017
Tomas Kron, Elizabeth Kyriakou, Jeffrey C. Crosbie
Synchrotron radiation has unique properties but has not yet found wide use in medicine. This is perhaps not too surprising; the main reason is that synchrotrons are scientific research tools in a research facility setting, not a clinical environment. Furthermore, of the 50 or so synchrotrons worldwide, fewer than six have the capability to handle human patients. However, synchrotron radiation has shown promise for both diagnostic and therapeutic applications [1,2]. There are several features that make this type of radiation unique for many applications as varied as crystallography in bioscience, forensic analysis, and advance material research P340. Given the usefulness of X-rays in many parts of medicine, it is not surprising that synchrotron radiation is being explored for medical applications such as radiography and radiotherapy.
Fabrication of BioMEMS Devices
Published in Simona Badilescu, Muthukumaran Packirisamy, BioMEMS, 2016
Simona Badilescu, Muthukumaran Packirisamy
As shown in Figure 7.21, high-intensity and low-divergence x-rays are used as the exposure source for lithography. The x-rays are usually produced by a synchrotron radiation source. Polymethylmethacrylate (PMMA) is used as the x-ray resist. The thicknesses of several hundreds of microns and aspect ratios (depth-to-width ratio) of more than one hundred have been achieved by using LIGA technology. A characteristic x-ray wavelength of 0.2 nm allows the transfer of a pattern from a high-contrast x-ray mask to a resist layer with a thickness of up to 1,000 µm, so that a resist relief may be generated with an extremely high ratio. The openings in the patterned resist can be preferentially plated with metal, yielding a highly accurate complementary replica of the original resist pattern. The mold is then dissolved away to leave behind plated structures with sidewalls that are vertical and smooth. It is also possible to use the plated metal structures as an injection mold for plastic resins. After curing, the metallic mold is removed, leaving behind microreplicas of the original pattern. By combining LIGA with the use of a sacrificial layer, it is also possible to realize freestanding micromechanical components.
An overview of the methods for analyzing the chemical forms of metals in plants
Published in International Journal of Phytoremediation, 2022
Jiawei Yang, Lin Sun, Xing Shen, Min Dai, Imran Ali, Changsheng Peng, Iffat Naz
The method of direct detection of different forms of metals in plants is based on the X-ray absorption spectrum of Synchrotron radiation. Synchrotron radiation is the electromagnetic radiation emitted along the tangent direction of the orbit by charged particles traveling close to the speed of light. It was first discovered on the synchrotron in 1947. XAS is a material analysis technique based on synchrotron radiation using absorption spectrum. The principle is that, according to the different composition and structure of the sample and the difference in X-ray absorption intensity of the sample, the intensity of X-ray passing through the sample will attenuate to different degrees (Watson 1980). According to the different attenuation degrees, the X-ray absorption spectrum can analyze information such as material element composition, electron state and microstructure (Kroukamp et al. 2016). XAS spectrum can be divided into two parts: X-Ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure EXAFS (Bunker 2010; GAUR 2013). As shown in Figure 1, XANES was within 50 eV above the absorption edge, while EXAFS (50–1,000 eV) was above the absorption edge in the region above 50 eV (Zhao et al. 2019).
Estimation of Absorbed Dose Due to Gas Bremsstrahlung Based on Residual Gas in Electron Storage Rings
Published in Nuclear Science and Engineering, 2023
Akihiro Takeuchi, Masayuki Hagiwara, Hiroki Matsuda, Toshiro Itoga, Hiroyuki Konishi
Synchrotron radiation (SR) facilities are used for various applications in the fields of material, medical, industrial, and fundamental science. Since the 2000s, many SR facilities focusing soft-X-ray applications based on several–giga-electron-volt electron storage rings have been constructed and operated globally. These facilities are classified as fourth generations in terms of their design of SR generations and application.[1] The fourth-generation SR facilities are based on insertion devices and multibend achromat lattices to deliver stable X-ray beams with higher brightness and coherence than the existing SR facilities.[2]
Design of an interference system for measuring the transverse beam size in HLS-II
Published in International Journal of Optomechatronics, 2022
Sanshuang Jin, Yunkun Zhao, Baogen Sun, Leilei Tang, Fangfang Wu, Tianyu Zhou, Ping Lu, Jigang Wang
Synchrotron Radiation (SR) refers to the electromagnetic wave radiated when the acceleration state of charged particles changes. The electron beam in a storage ring can radiate a wide spectrum light when traveling through the Bending Magnet (BM). The SR light source has been widely used in the fields of condensed-matter physics, medical research, biochemistry, materials and advanced manufacturing processes due to its excellent characteristics of high brightness, high polarization and high stability.