MARC details
| 000 -LEADER |
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| fixed length control field |
04074nam a22002177a 4500 |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION |
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| fixed length control field |
231121b |||||||| |||| 00| 0 eng d |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER |
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| Classification number |
620.5 DAR |
| 100 ## - MAIN ENTRY--PERSONAL NAME |
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| Personal name |
Darukesha, B H M |
| 245 ## - TITLE STATEMENT |
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| Title |
Interaction of ionising radiations with nanoparticles |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) |
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| Place of publication, distribution, etc |
Bangalore: |
| Name of publisher, distributor, etc |
Indian Institute of Science, |
| Date of publication, distribution, etc |
2023 |
| 300 ## - PHYSICAL DESCRIPTION |
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| Extent |
vi, 398p. : |
| Other physical details |
col. ill. |
| Accompanying material |
e-Thesis |
| Size of unit |
11.75 MB |
| 500 ## - GENERAL NOTE |
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| General note |
includes bibliographical references and index |
| 502 ## - DISSERTATION NOTE |
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| Dissertation note |
PhD; 2023; Instrumentation and Applied Physics |
| 520 ## - SUMMARY, ETC. |
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| Summary, etc |
The interaction of ionizing radiations such as alpha, beta, gamma, and X-rays with matter-atbulk has been studied intensively for many decades. However, the interaction of ionizing<br/>radiations with matter-at-nanoscale is studied sparsely due to the lack of experimental<br/>techniques. Thus, there exists a gap in knowledge. The present thesis contributes to the<br/>development of an experimental technique for determining the outcomes of the interaction of<br/>given ionizing radiation with given nanoparticles. The technique involves obtaining pulse<br/>height spectra of ionizing radiation with a liquid scintillator before and after loading the<br/>nanoparticles under identical conditions and observing the variations in spectra to infer the<br/>outcomes of the interactions.<br/>The study investigates the outcomes of interactions of gamma-rays, X-rays, beta- and alpharadiations with about twenty-five types of nanoparticles. It ascertains the effects of the nature<br/>and energy of radiations, species, size, and concentration of nanoparticles on the outcome of<br/>interactions. It demonstrates that the interaction of ionizing radiations with nanomaterials<br/>differs from those with their bulk counterparts. The interaction of low-energy photons (X-rays<br/>from 55Fe or a 40 kVp gun or gamma-rays from 241Am or 133Ba) with nanoparticles of Gd2O3,<br/>HfO2, and ZrO2 leads to the emission of numerous electrons from the nanoparticles. However,<br/>the nanoparticles of Au, Fe2O3, Pd, W, and WO3 interact with low-energy photons but inhibit<br/>the exit of electrons from them. Thus, the interaction of low-energy photons varies with the<br/>species of nanoparticles. Further, photons of a given energy range interact with the<br/>nanoparticles intensely. These are the two new results from this study. High-energy gamma<br/>radiations seldom interact with nanoparticles. The interactions of beta- and alpha-radiations<br/>result in the emission of electrons from all species of nanoparticles.<br/>Practical applications like –nanoparticle radiosensitization for cancer treatment; the<br/>development of efficient-fast-large-affordable gamma-detectors; and the development of Pbfree, efficient, light-weight gamma-ray shields—rely on the interaction of ionizing radiations<br/>with nanoparticles. They either seek or benefit from empirical knowledge of the outcome of<br/>interactions. As the lack of mechanistic understanding of nanoparticle radiosensitization has<br/>delayed its field implementation, researchers seek the outcomes of ‘physical interaction of<br/>ionizing radiations with nanomaterials’. Since the process-related challenges have hindered the<br/>upscaling of detectors or shields and have kept their studies in exploratory mode, certainty<br/>gained on the outcome of interactions offers much-needed directions.<br/>Nanoparticles of Gd2O3, HfO2, and LaF3 suit as dopants in plastic scintillators for developing<br/>efficient-fast-large-affordable gamma detectors. Those of WO3, Sn, and Fe2O3 suit as dopants<br/>for developing Pb-free, efficient gamma-ray shields. The results reason why the enhancement<br/>of photon detection efficiency of plastic scintillators is repeatedly reported with doping of only<br/>selected species of nanoparticles. They reason how nanoparticle-loaded polymers offer<br/>impressive shielding efficiencies for diagnostic photons. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
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| Topical term or geographic name as entry element |
nanoparticles |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
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| Topical term or geographic name as entry element |
ionizing radiations |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
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| Topical term or geographic name as entry element |
photon detection efficiency |
| 700 ## - ADDED ENTRY--PERSONAL NAME |
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| Personal name |
advised by Misra, Abha, Rajanna; K, Radhakrishna and V, Ravindra M |
| 856 ## - ELECTRONIC LOCATION AND ACCESS |
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| Uniform Resource Identifier |
https://etd.iisc.ac.in/handle/2005/6226 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) |
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| Koha item type |
Thesis |
