A theoretical ac impedance model of biological tissue has been proposed after studying a cellular membrane using X-ray diffraction technique [1], a metal/organic system using ac impedance spectroscopy [2] and reviewing two pieces of literature of similar topics [3,4]. This paper emphasizes ac impedance techniques which can be used to study any heterogeneous materials in order to develop a lumpe...

PURPOSE This work investigated the proton tissue-equivalence of various 3D printed materials. METHODS Three 3D printers were used to create 5 cm cubic phantoms made of different plastics with varying percentages of infill. White resin, polylactic acid (PLA), and NinjaFlex plastics were used. The infills ranged from 15% to 100%. Each phantom was scanned with a CT scanner to obtain the HU value...

The mechanical properties of surfaces of layered materials (highly oriented pyrolytic graphite, InSe, and GaSe) and single-crystal ionic materials (NaCl, KBr, and KCl) have been investigated at the nanometer scale by using nanoindentations produced with an atomic force microscope with ultrasharp tips. Special attention has been devoted to the elastic response of the materials before the onset o...

For the production of a clinical 15 MV photon beam, the design of accelerator head assembly has been optimized using Monte Carlo based FLUKA code. The accelerator head assembly consists of etarget, flattening filter, primary collimator and an adjustable rectangular secondary collimator. Accelerators used for medical radiation therapy generate continuous energy gamma rays called bremsstrahlung r...

Particle size distribution (PSD) affects properties of particulate materials and is used for denoting their quality and performance. Among many techniques available to measure PSD, many are quite often offline methods and are time consuming. Also methods like sieving involve, handling of the material physically and electromagnetically, which is healthy, if avoided for certain materials. Thus th...