Linear Accelerators
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. Biological X-ray irradiator characterization for use with small animals and cells
This study presents the characterization of an X-ray irradiator through dosimetric tests, which confirms the actual dose rate that small animals and cells will be exposed to during radiobiological experiments. We evaluated the linearity, consistency, repeatability, and dose distribution in the positions in which the animals or cells are placed during irradia
Braz J Med Biol Res. Publicado em: 02/03/2017
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2. Projeto e construção de placas espalhadoras e degradadoras de energia para uso em radioterapia com feixes de elétrons para doenças de pele / Project and construction of energy degrading and scattering plates for electron beam radiotherapy for skin diseases
There are many radiosensitive epidermotropics diseases such as mycosis fungoids and the syndrome of Sézary, coetaneous neoplasics originated from type T lymphocytes. Several studies indicate the eradication of the disease when treated with linear accelerators emitting electron beams with energies between 4 to 10 MeV. However, this treatment technique presen
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 24/06/2010
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3. Dose rate influence on deep dose deposition using a 6 MV x-ray beam from a linear accelerator
Linear accelerators used in radiation therapy treatments usually provide the capability of irradiating with different dose rates. The medical physicist may choose arbitrary the dose rate to use, although the relative biological effectiveness (RBE) varies with this physical parameter. In this work the measurements of absorbed dose of the x-ray beams from a Va
Brazilian Journal of Physics. Publicado em: 2009-06
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4. Termalização de feixes não-neutros ultra-intensos sob confinamento solenoidal em canais lineares
As aplicações envolvendo confinamento e aceleração de feixes de partículas carregadas em canais lineares são inúmeras em diversas áreas do conhecimento. A evolução da engenharia dos aceleradores lineares de partículas de próxima geração está fortemente condicionada ao melhor entendimento de fenômenos não-lineares como a formação de halo, i
Publicado em: 2008
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5. Compact charged stars
We investigate the possibility that charged compact objects could be the accelerators of high energy cosmic rays. In order to do so, we choose to first solve numerically a system of differential equations describing the structure of charged compact objects, including the generalization of the Tolman-Oppenheimer-Volkoff equation for this class of objects. We
Brazilian Journal of Physics. Publicado em: 2007-07
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6. Implantação de um programa de controle de qualidade para sistemas de planejamento de tratamento computadorizados de acordo com o TRS 430 / Implementation of a quality assurance program for computerized treatment planning systems according to TRS 430
This work presents the guidelines and necessary tests tom implement a quality assurance program for Eclipse 7.3.10 from Varian at Hospital das Clinicas, Sao Paulo University School of Medicine - Brazil, in accordance with the new IAEA publication TRS 430. The recommended tests for the TRS 430 air mainly classified into acceptance tests, commissioning (dosime
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/04/2006
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7. Intercomparação de colimadores de múltiplas lâminas para implementação de terapia de feixes de intensidade modulada / Multileaf collimator intercomparison for intensity modulated radiation therapy implementation
Neste trabalho é apresentada uma intercomparaçào das características dosimétricas entre três sistemas de colimadores multi-lâminas: Varian Millenium com 120 lâminas, mMLC m3 Brainlab e Varian Mark II ambos com 52 lâminas. A largura da projeção das lâminas no isocentro e na região central do campo é de 0,5 cm; 0,35 cm e 1,0 cm respectivamente. F
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/01/2006
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8. Desenvolvimento de um sistema postal para controle de qualidade de dosimetrias realizadas em feixes de fotons produzidos em aceleradores lineares de uso clinico
There are a great number of parameters involved in the performance of a clinical linear accelerator. These parameters must be verified periodically to eliminate errors in the treatment performed. Such verifications are usually made by clinical physicists with special equipment?s. With the intent of helping and optimizing the physicists work, the organization
Publicado em: 1984
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9. Numerical analysis of weakly nonlinear wave turbulence
We consider the propagation of weakly nonlinear waves such as plasma waves, surface water waves, the interaction of laser beams with matter, particle accelerators, etc. Specifically, we study internal waves in the ocean. Hamilton's principle is used to write the fluid equations in Hamiltonian form in terms of linear eigenmode amplitudes. Numerical studies ar
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10. Secondary neutron spectra from modern Varian, Siemens, and Elekta linacs with multileaf collimators
Neutrons are a by-product of high-energy x-ray radiation therapy (threshold for [γ,n] reactions in high-Z material ∼7 MeV). Neutron production varies depending on photon beam energy as well as on the manufacturer of the accelerator. Neutron production from modern linear accelerators (linacs) has not been extensively compared, particularly in terms of the
American Association of Physicists in Medicine.