The present work experimentally investigates the correlations between ultrasonic attenuation coefficient and void content with the porosity 0.03%-4.96% of the carbon fiber-reinforced composite (CFRC) samples. The ultrasonic echo immersion bottom reflection technique with 5MHz flat probe is adopted to determine the attenuation coefficient and the metallographic microscope is used to measure the ...

This paper presents the precise method to estimate the dependence of linear and mass attenuation coefficients of gamma rays on concentration of Manganese (II) chloride (MnCl2). The experiment was done using GSpec gamma spectroscopy system. The GSpec consists 2‖x 2‖ NaI (Tl) detector with Multichannel analyzer (MCA). The GSpec has built in 14 Pin PMT base.The GSPEC is pc based Gamma Ray Spectros...

background: photon attenuation as an inevitable physical phenomenon influences on the diagnostic information of spect images and results to errors in accuracy of quantitative measurements. this can be corrected via different physical or mathematical approaches. as the correction equation in mathematical approaches is nonlinear, in this study a new method of linearization called ‘piece wise line...

Doppler optical coherence tomography (OCT) is a technique to image tissue morphology and to measure flow in turbid media. In its most basic form, it is based on single (Mie) scattering. However, for highly scattering and dense media multiple and concentration dependent scattering can occur. For Intralipid solutions with varying scattering strength, the effect of multiple and dependent scatterin...

introduction: the photoelectric attenuation coefficient of substances is known to depend upon the energy e of the photon and the effective atomic number of substances (zeff) as (zeff x /e y ).  no definitive values about these indices x, y are given in the literature. the index x is said to lie between, 3.0 and 4.0, while for ‘y’ different values have been assigned, between 3.0 and 4.0. methodo...

background: radiation shielding properties is an important for a material wish can be used the photon attenuation coefficients of clay produced using different rate of boron have been measured for the purpose of radioactive waste disposal. materials and methods: the measurement has been performed using gamma spectrometer contains nai (tl) detector at the photon energies of 662, 1173 and 1332 ke...

Aims Dual energy CT imaging enables discrimination of materials with similar attenuation coefficients. By acquiring two CT scans at different X-ray energies of the same sample, the energy dependence of the linear attenuation coefficient can be exploited to differentiate between materials. Dual energy CT has been widely used to distinguish bone from vascular contrast agents that contain elements...

The purpose of this study is to propose and investigate a new approach for discriminating between focal and non-focal hemispheres in intractable temporal lobe epilepsy, based on applying multivariate time series analysis to the discharge-free background brain activity observed in nocturnal electrocorticogram (ECoG) time series. Five unilateral focal patients and one bilateral focal patient were...

In this study, using methacrylic and ascorbic acid in gelatin initiated by copper (MAGIC-f) polymer gel after megavoltage energy exposure, the sensitivity of the ultrasound velocity and attenuation coefficient dose-dependent parameters was evaluated. The MAGIC-f polymer gel was irradiated under 1.25 MeV cobalt-60, ranging from 0 to 60 Gy in 2-Gy steps, and received dose uniformity and accuracy ...