Most HWRs currently use natural uranium fuel. Using enriched uranium fuel results in a significant improvement in fuel cycle costs and uranium utilization. On the other hand, reactivity changes of HWRs over the full range of operating conditions from cold shutdown to full power are small. This reduces the required reactivity worth of control devices and minimizes local flux distribution perturb...

Introduction: With the extensive application of radiation sources and radioactive materials in various fields, the study of attenuation and absorption of X-rays and gamma-rays in several materials has become an essential and interesting field of research. Glass materials are possible alternatives of concretes for radiation-shielding materials.   Materials and Methods:...

abstract background: accurate methods of radiation therapy dose calculation. there are different monte carlo codesfor simulation of photons, electrons and the coupled transport of electrons and photons. mcnpis a general purpose monte carlo code that can be used for electron, photon and coupledphoton-electron transport.monte carlo simulation of radiation transport is considered to be one of the ...

introduction: in this paper, by complete definition of human eye containing the various parts and their materials, the difference between this model and a homogeneous water phantom are compared for two ophthalmic plaques using 125i and 103pd. material and methods: the simulation of the two phantoms were performed in the mcnp-4c code and by using the geometry of a three-dimensional eye, differen...

AIM Exact knowledge of dosimetric parameters is an essential pre-requisite of an effective treatment in radiotherapy. In order to fulfill this consideration, different techniques have been used, one of which is Monte Carlo simulation. MATERIALS AND METHODS This study used the MCNP-4C to simulate electron beams from Neptun 10 PC medical linear accelerator. Output factors for 6, 8 and 10 MeV el...

MCNP is widely used Monte Carlo program in reactor and nuclear physics. However, an option of simulating electrons was added into the code a few years ago. With this extension MCNP became a code, potentially applicable for applications in medical physics. In 1997, a new version of the code, named MCNP4B was released, which contains several improvements in electron transport modelling. To test s...

BACKGROUND Obtaining high quality images in Single Photon Emission Tomography (SPECT) device  is the most important goal in nuclear medicine. Because if image quality is low, the possibility of making a mistake in diagnosing and treating the patient will rise. Studying effective factors in spatial resolution of imaging systems is thus deemed to be vital. One of the most important factors in SPE...

ABSTRACT Background: accurate methods of radiation therapy dose calculation. There are different Monte Carlo codesfor simulation of photons, electrons and the coupled transport of electrons and photons. MCNPis a general purpose Monte Carlo code that can be used for electron, photon and coupledphoton-electron transport.Monte Carlo simulation of radiation transport is considered to be one of the ...