نتایج جستجو برای: scattered radiation

تعداد نتایج: 258284  

2010
Marcela Morvidone Maï K. Nguyen Tuong T. Truong Habib Zaidi

Radon transforms defined on smooth curves are well known and extensively studied in the literature. In this paper, we consider a Radon transform defined on a discontinuous curve formed by a pair of half-lines forming the vertical letter V. If the classical two-dimensional Radon transform has served as a work horse for tomographic transmission and/or emission imaging, we show that this V-line Ra...

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Journal: :Nature nanotechnology 2011
Daniel Y Joh Jesse Kinder Lihong H Herman Sang-Yong Ju Michael A Segal Jeffreys N Johnson Garnet K-L Chan Jiwoong Park

Although metallic nanostructures are useful for nanoscale optics, all of their key optical properties are determined by their geometry. This makes it difficult to adjust these properties independently, and can restrict applications. Here we use the absolute intensity of Rayleigh scattering to show that single-walled carbon nanotubes can form ideal optical wires. The spatial distribution of the ...

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2000
P. R. Costa L. V. E. Caldas

INTRODUCTION The NCRP 49 (1976) (1) standard presents a methodology to determine protective shielding for diagnostic and therapeutic X-ray rooms. This methodology has been reviewed by several authors in the recent years (2). This work presents contributions for this new shielding evaluation method, taking into account information regarding patient attenuation and scattering, as well as workload...

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2000
William E. Vargas Gunnar A. Niklasson

Light diffusers for daylighting applications should have a substantial diffuse transmittance with the forward scattered light distributed as isotropically as possible. We consider the possibility of using pigmented polymer foils for this purpose and propose a method for their theoretical optimization. The amount of electromagnetic energy transmitted through a particulate film illuminated with u...

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2004
J. Tabary P. Hugonnard F. Mathy R. Guillemaud

In an X-ray radiography, scattering of photons from the inspected object, as well as backscattering or scattering from the environment, may have significant deleterious effects on image quality, reducing the relative contrast of the flaw indication. Therefore, development of computational models simulating scattering in radiographic studies is of primary interest, to correctly evaluate flaw det...

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Journal: Iranian Journal of Medical Physics 2018
Azadeh Soleimani Elyas Sanaei Marjaneh Mir-Sadraee Mohammad Mohammadi, Mohammad Taghi Batiar,

Introduction: Rectal and bladder cancer are the most common disease among young man. Although External Radiotherapy (EBRT) is one of the most effective treatment options introduced so far, the testis undesired radiation dose increases the risk of infertility and hormonal malfunctioning. The testicles are usually outside of the radiation field, but they can be exposed either to ...

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2008
V. G. Gurzadyan A. Kashin A. Margarian O. Bartalini V. Bellini A. D ’ Angelo J. - P. Didelez A. Fantini G. Gervino F. Ghio B. Girolami A. Giusa M. Guidal E. Hourany S. Knyazyan V. Kouznetsov R. Kunne A. Lapik P. Levi Sandri A. Lleres S. Mehrabyan D. Moricciani V. Nedorezov C. Perrin D. Rebreyend G. Russo N. Rudnev C. Schaerf M. - C. Sutera A. Turinge

— The measurement of the Compton edge of the scattered electrons in GRAAL facility in European Synchrotron Radiation Facility (ESRF) in Grenoble with respect to the Cosmic Microwave Background dipole reveals up to 10σ variations larger than the statistical errors. We now show that the variations are not due to the frequency variations of the accelerator. The nature of Compton edge variations re...

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Journal: :The Astrophysical journal 2000
Dermer Böttcher

The blast-wave model for gamma-ray bursts (GRBs) has been called into question by observations of spectra from GRBs that are harder than can be produced through optically thin synchrotron emission. If GRBs originate from the collapse of massive stars, then circumstellar clouds near burst sources will be illuminated by intense gamma radiation, and the electrons in these clouds will be rapidly sc...

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Journal: :Optics express 2012
Thomas J Constant Tim S Taphouse Helen J Rance Stephen C Kitson Alastair P Hibbins J Roy Sambles

Optical excitation of surface plasmons polaritons (SPPs) on a 'zig-zag diffraction grating' is explored. The fabricated silver grating consists of sub-wavelength grooves 'zig-zagged' along their length, providing a diffractive periodicity to visible radiation. SPPs propagating in the diffraction plane and scattered by an odd number of grating vectors are only excited by TE polarized radiation, ...

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2005
Erik Everson

The goal of the ANITA project is to detect neutrino interactions within the Antarctic ice cap. To do so, a radio antenna is used to detect radiation produced by the interaction. The radiation is scattered as it passes through the rough Antarctic surface. Power distributions of light through wavelength scale rough ground glass diffusers are investigated in hopes of understanding how the power di...

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نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید

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