Synthesis and Characterization of Nanocomposite Scintillators for Radiation Detection PDF Download

Author: Sunil Kumar Sahi
Publisher:
ISBN:
Category : Nanocomposites (Materials)
Languages : en
Pages : 163

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Book Description
Inorganic single crystal and organic (plastic and liquid) scintillators are commonly used for radiation detection. Inorganic single crystals are efficient and have better energy resolution compared to organic scintillators. However, inorganic single crystals are difficult to grow in large size and hence expensive. On the other hand, fast decay time and ease of fabrication makes organic scintillators attractive for many applications. However, poor energy resolution of organic scintillators limits its applications in gamma ray spectroscopy. The poor energy resolution is due to the low Z-Value and low density of organic scintillator. The Z-value of organic plastic scintillator can be increase by loading nanoparticles in plastic matrix. It is expected that the increase in Z-value would result in improve energy resolution of nanocomposite scintillator. However, the loss of optical transparency due to nanoparticles loading is one of the major concerns of nanocomposite scintillators. In this dissertation, we used different methods to synthesize LaxCe1-xF3 nanoparticles with high dispersion in polymer matrix. High nanoparticle dispersion is important to load high concentration of nanoparticles into polymer matrix without losing the transparency of the polymer matrix. The as synthesized nanoparticles are dispersed into monomers and polymerized using heat initiated bulk polymerization method. Nanoparticles are characterized using TEM, XRD, FTIR and TGA. The optical and scintillation properties of nanoparticles and nanocomposites are studied using spectroscopic techniques. The pulse height spectra obtained using nanocomposite fabricated by loading up to 30 wt% nanoparticles clearly show a photopeak for the 122 keV line of the Co-57 isotope. The generation of the photopeak is due to the enhanced photoelectric effect as a result of increased effective atomic number (Zeff) and density of nanocomposite scintillator. The pulse height spectra of Cs-137 gamma source show a full energy peak at around 622 keV, due to the escape of La and Ce K[alpha] X-rays. The fabrication process of transparent nanocomposite scintillator is discussed in details.

Author: Mikhail Korzhik
Publisher: Springer Nature
ISBN: 3030219704
Category : Science
Languages : en
Pages : 319

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Book Description
This proceedings book presents dual approaches to examining new theoretical models and their applicability in the search for new scintillation materials and, ultimately, the development of industrial technologies. The ISMART conferences bring together the radiation detector community, from fundamental research scientists to applied physics experts, engineers, and experts on the implementation of advanced solutions. This scientific forum builds a bridge between the different parts of the community and is the basis for multidisciplinary, cooperative research and development efforts. The main goals of the conference series are to review the latest results in scintillator development, from theory to applications, and to arrive at a deeper understanding of fundamental processes, as well as to discover components for the production of new generations of scintillation materials. The book highlights recent findings and hypotheses, key advances, as well as exotic detector designs and solutions, and includes papers on the microtheory of scintillation and the initial phase of luminescence development, applications of the various materials, as well as the development and characterization of ionizing radiation detection equipment. It also touches on the increased demand for cryogenic scintillators, the renaissance of garnet materials for scintillator applications, nano-structuring in scintillator development, trends in and applications for security, and exploration of hydrocarbons and ecological monitoring.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Measurement of the neutron capture cross-sections of a number of short-lived isotopes would advance both pure and applied scientific research. These cross-sections are needed for calculation of criticality and waste production estimates for the Advanced Fuel Cycle Initiative, for analysis of data from nuclear weapons tests, and to improve understanding of nucleosynthesis. However, measurement of these cross-sections would require a detector with a faster signal decay time than those used in existing neutron capture experiments. Crystals of faster detector materials are not available in sufficient sizes and quantities to supply these large-scale experiments. Instead, we propose to use nanocomposite detectors, consisting of nanoscale particles of a scintillating material dispersed in a matrix material. We have successfully fabricated cerium fluoride (CeF3) nanoparticles and dispersed them in a liquid matrix. We have characterized this scintillator and have measured its response to neutron capture. Results of the optical, structural, and radiation characterization will be presented.

Author: Mikhail Korzhik
Publisher: Springer
ISBN: 3319684655
Category : Science
Languages : en
Pages : 346

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Book Description
This volume provides a broad overview of the latest achievements in scintillator development, from theory to applications, and aiming for a deeper understanding of fundamental processes, as well as the discovery and availability of components for the production of new generations of scintillation materials. It includes papers on the microtheory of scintillation and the initial phase of luminescence development, applications of the various materials, and development and characterization of ionizing radiation detection equipment. The book also touches upon the increased demand for cryogenic scintillators, the renaissance of garnet materials for scintillator applications, nano-structuring in scintillator development, development and applications for security, and exploration of hydrocarbons and ecological monitoring.

Author: Matthieu Hamel
Publisher: Springer Nature
ISBN: 3030734889
Category : Science
Languages : en
Pages : 647

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Book Description
This book introduces the physics and chemistry of plastic scintillators (fluorescent polymers) that are able to emit light when exposed to ionizing radiation, discussing their chemical modification in the early 1950s and 1960s, as well as the renewed upsurge in interest in the 21st century. The book presents contributions from various researchers on broad aspects of plastic scintillators, from physics, chemistry, materials science and applications, covering topics such as the chemical nature of the polymer and/or the fluorophores, modification of the photophysical properties (decay time, emission wavelength) and loading of additives to make the material more sensitive to, e.g., fast neutrons, thermal neutrons or gamma rays. It also describes the benefits of recent technological advances for plastic scintillators, such as nanomaterials and quantum dots, which allow features that were previously not achievable with regular organic molecules or organometallics.

Author: Martin Nikl
Publisher: CRC Press
ISBN: 1315340976
Category : Science
Languages : en
Pages : 361

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Book Description
The literature so far has reviewed only single-crystal and, up to some extent, optical ceramic scintillators. This book introduces and describes in detail the research and development in thin film scintillators, glass ceramics, as well as nanocomposite and optical ceramics prepared by spark plasma sintering. It also features example of an in-depth study of a ZnO-based powder phosphor material. Both technology description and various characterization aspects are provided together with application hints. No other book has been published so far that includes and reviews the scintillator materials covered in this book with their specific technologies. Moreover, technological description is merged with detailed characterization, and the application potential is discussed as well. This book is intended for a wide audience, including postgraduate and PhD students and scientists working in the field of scintillators and phosphors. The extended introductory text, which has a textbook character, will be of immense benefit to students and non-specialists, too.

Author: Takayuki Yanagida
Publisher: Wiley
ISBN: 9781119583325
Category : Technology & Engineering
Languages : en
Pages : 416

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Book Description
Phosphors for Radiation Detector Phosphors for Radiation Detectors Discover a comprehensive overview of luminescence phosphors for radiation detection In Phosphors for Radiation Detection, accomplished researchers Takayuki Yanagida and Masanori Koshimizu deliver a state-of-the-art exploration of the use of phosphors in radiation detection. The internationally recognized contributors discuss the fundamental physics and detector functions associated with the technology with a focus on real-world applications. The book discusses all forms of luminescence phosphors for radiation detection used in a variety of fields, including medicine, security, resource exploration, environmental monitoring, and high energy physics. Readers will discover discussions of dosimeter materials, including thermally stimulated luminescent materials, optically stimulated luminescent materials, and radiophotoluminescence materials. The book also covers transparent ceramics and glasses and a broad range of devices used in this area. Phosphors for Radiation Detection also includes: Thorough introductions to ionizing radiation induced luminescence, organic scintillators, and inorganic oxide scintillators Comprehensive explorations of luminescent materials, including discussions of materials synthesis and their use in gamma-ray, neutron, and charged particle detection Practical discussions of semiconductor scintillators, including treatments of organic-inorganic layered perovskite materials for scintillation detectors In-depth examinations of thermally stimulated luminescent materials, including discussions of the dosimetric properties for photons, charged particles, and neutrons Relevant for research physicists, materials scientists, and electrical engineers, Phosphors for Radiation Detection is an also an indispensable resource for postgraduate and senior undergraduate students working in detection physics.

Author: Meredith Brooke Barta
Publisher:
ISBN:
Category : Gamma ray detectors
Languages : en
Pages :

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Book Description
In recent years, the United States Departments of Homeland Security (DHS) and Customs and Border Protection (CBP) have been charged with the task of scanning every cargo container crossing domestic borders for illicit radioactive material. This is accomplished by using gamma-ray detection systems capable of discriminating between non-threatening radioisotopes, such as Cs-137, which is often used in nuclear medicine, and fissile material, such as U-238, that can be used to make nuclear weapons or "dirty" bombs. Scintillation detector systems, specifically thallium-doped sodium iodide (NaI(Tl)) single crystals, are by far the most popular choice for this purpose because they are inexpensive relative to other types of detectors, but are still able to identify isotopes with reasonable accuracy. However, increased demand for these systems has served as a catalyst for the research and development of new scintillator materials with potential to surpass NaI(Tl). The focus of a majority of recent scintillator materials research has centered on sintered transparent ceramics, phosphor-doped organic matrices, and the development of novel single crystal compositions. Some of the most promising new materials are glass-ceramic nanocomposites. By precipitating a dense array of nano-scale scintillating crystals rather than growing a single monolith, novel compositions such as LaBr3(Ce) may be fabricated to useful sizes, and their potential to supersede the energy resolution of NaI(Tl) can be fully explored. Also, because glass-ceramic synthesis begins by casting a homogeneous glass melt, a broad range of geometries beyond the ubiquitous cylinder can be fabricated and characterized. Finally, the glass matrix ensures environmental isolation of the hygroscopic scintillating crystals, and so glass-ceramic scintillators show potential to serve as viable detectors in alpha- and neutron-spectroscopy in addition to gamma-rays. However, for the improvements promised by glass-ceramics to become reality, several material properties must be considered. These include the degree of control over precipitated crystallite size, the solubility limit of the glass matrix with respect to the scintillating compounds, the variation in maximum achievable light yield with composition, and the peak wavelength of emitted photons. Studies will focus on three base glass systems, sodium-aluminosilicate (NAS), sodium-borosilicate (NBS), and alumino-borosilicate (ABS), into which a cerium-doped gadolinium bromide (GdBr3(Ce)) scintillating phase will be incorporated. Scintillator volumes of 50 cubic centimeters or greater will be fabricated to facilitate comparison with NaI(Tl) crystals currently available.

Author: Hao Yu
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
Fast scintillators with spectroscopic gamma response are essential in nuclear security and medical imaging. However, few individual scintillation materials exhibit both fast scintillation decay and excellent photopeak energy resolution. This dissertation strives to develop organic scintillators for fast spectroscopic gamma detection. The focus is to load high-Z nanoparticles (NPs) into plastics and liquids. A nanocomposite plastic scintillator comprising 40 wt% hafnium oxide nanoparticles uniformly dispersed in a luminescent plastic matrix is synthesized. The nanoparticles have an average diameter of 4.2 nm and are covalently attached to the polymer matrix to prevent agglomeration. A progressive curing protocol using a low-temperature and a high-temperature initiator is developed to synthesize centimeter-size nanocomposites. The addition of 5 vol% divinylbenzene is key to boosting bulk transmittance, resulting in a measured transmittance of around 80% across the emission range. Gamma pulse scintillation has a fast decay time constant of 2.5 ns and a modest light output of 8,000-9,000 photons/MeV. The gamma scintillation shows energy proportionality from 32 to 1275 keV. A 1.93 cm3 nanocomposite produces photopeaks at 32 and 662 keV for 137Csand at 511 and 1275 keV for 22Na. The photopeak energy resolution at 662 keV is 7.2%-9.1%. While the energy resolution is approaching that of single crystal scintillators, it is negatively impacted by the trade-off between high NP loading and diminishing light output. To address this issue, CsPbBr3 quantum dots (QDs) are loaded into liquid scintillators up to 40 wt%. Pyrromethene 580 (PM-580), a fluorescent dye, is co-dissolved in the solution as a fluorescence resonance energy transfer acceptor to overcome the self-absorption of the QDs. The rapid energy transfer from the QDs to PM-580 also accelerates the scintillation decay kinetics. The decay time constant is 24.3 ns, faster than most inorganic crystal scintillators. The light output is 7,300 photons/MeV at 40 wt% QD loading. Gamma pulse spectroscopy of the 40 wt% QD liquid produces a 662 keV gamma photopeak with a 27% energy resolution, demonstrating the potential of the CsPbBr3 QD loaded organic scintillators for spectroscopic gamma detection.

Author: Alan Owens
Publisher: CRC Press
ISBN: 1351629166
Category : Science
Languages : en
Pages : 786

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Book Description
Choice Recommended Title, July 2020 Bringing together material scattered across many disciplines, Semiconductor Radiation Detectors provides readers with a consolidated source of information on the properties of a wide range of semiconductors; their growth, characterization and the fabrication of radiation sensors with emphasis on the X- and gamma-ray regimes. It explores the promise and limitations of both the traditional and new generation of semiconductors and discusses where the future in semiconductor development and radiation detection may lie. The purpose of this book is two-fold; firstly to serve as a text book for those new to the field of semiconductors and radiation detection and measurement, and secondly as a reference book for established researchers working in related disciplines within physics and engineering. Features: The only comprehensive book covering this topic Fully up-to-date with new developments in the field Provides a wide-ranging source of further reference material