Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Appl Radiat Isot ; 206: 111193, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412773

RESUMO

Total, whole-atom, individual and integrated Compton scattering cross sections and Compton energy absorption scattering cross sections are evaluated for light elements, such as, H, C, N, O, P, and Ca, with relativistic impulse approximation methods. Most of the phantom materials composed of these elements, which are the basic constituents of biological soft-tissue and attenuation through them, provides potential source of information. Compton scattering cross-sections for few biological materials, such as, H2O, C2H4, C8H8, C5H8O2, C6H11NO, C16H14O3, C55H102O6, [Ca3(PO4)]3Ca (OH)2 of medical interest, have been evaluated with the use of double differential scattering cross-section based on impulse approximation. Utilized these values to evaluate the Compton energy absorption cross sections and Compton component of mass energy absorption coefficients (cm2/g) in the energy region from 0.005 to 10 MeV. The derived results are compared with the theoretical tabulations.

2.
J Xray Sci Technol ; 20(3): 291-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22948351

RESUMO

Synchrotron-based micro-CT was utilized to image the embedded biological soft-tissue of a small animal shell. Micro-CT images of the biological soft-tissue were acquired using 20, 25, and 27 keV synchrotron X-rays with contrast agents, such as water, physiological saline and iodine. Visualized the complex features of the animal at the above energies with water, physiological saline and iodine. The choice of the optimum energy was chosen based on the contrast mechanisms to know more about soft-matter and the associated internal complex biological features of the small animal shell. This way, the images at 27 keV (optimum energy) was reasonably acceptable for better visualization of the interior micro-architecture, such as soft-anatomy, physiology and internal organs of the animal with better visibility. The introduction of water, physiological, or iodine as contrast agents is shown to enhance minute image features in synchrotron-based tomographic imaging.


Assuntos
Exoesqueleto/diagnóstico por imagem , Caramujos/anatomia & histologia , Síncrotrons , Microtomografia por Raio-X/instrumentação , Microtomografia por Raio-X/métodos , Animais , Meios de Contraste/química , Imageamento Tridimensional , Iodo/química , Cloreto de Sódio/química , Água/química
3.
Appl Radiat Isot ; 70(8): 1570-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22732392

RESUMO

The introduction of water, physiological, or iodine as contrast agents is shown to enhance minute image features in synchrotron-based X-ray diffraction radiographic and tomographic imaging. Anatomical features of rat kidney, such as papillary ducts, ureter, renal artery and renal vein are clearly distinguishable. Olfactory bulb, olfactory tact, and descending bundles of the rat brain are visible with improved contrast.


Assuntos
Meios de Contraste , Diagnóstico por Imagem/métodos , Imagens de Fantasmas , Síncrotrons , Animais , Diagnóstico por Imagem/instrumentação , Ratos
4.
J Xray Sci Technol ; 18(3): 327-37, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20714090

RESUMO

Synchrotron-based scattered radiation form low-contrast phantom materials prepared from polyethylene, polystyrene, nylon, and Plexiglas is used as test objects in X-ray CT was examined with 8, 10 and 12 keV X-rays. These phantom materials of medical interest will contains varying proportions of low atomic number elements. The assessment will allowed us to estimate the fluorescence to total scattered radiation. Detected the fluorescence spectra and the associated scattered radiation from calcium hydroxyapatite phantom with 8, 10 and 12 keV synchrotron X-rays. Samples with Bonefil (60% and 70% of calcium hydroxyapatite) and Bone cream (35 approximately 45% of calcium hydroxyapatite), were used. Utilized the X-ray micro-spectroscopy beamline facility, X27A, available at NSLS, BNL, USA. The primary beam with a spot size of the order of approximately 10 mum, has been used for focusing. With this spatial resolution and high flux throuput, the synchrotron-based scattered radiation from the phantom materials were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector.


Assuntos
Imagens de Fantasmas , Espalhamento de Radiação , Síncrotrons , Tomografia Computadorizada por Raios X/instrumentação , Durapatita/química , Humanos , Nylons/química , Polietileno/química , Polimetil Metacrilato/química , Poliestirenos/química , Espectrometria de Fluorescência , Raios X
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA