modification of the mechanical properties of silicone rubber were considered for drug delivery systems by using high-energy electron beam (e-beam). in this research work, two different medical grades of silicone rubbers were used to prepare matrices containing 10wt% progesterone with 2 mm thickness and irradiated with e-beam at dose range of 25 up to 200 kgy. then, the mechanical properties as ...

experiments were carried out to observe the influence of loading type on concrete beam specimens. beam specimens made of similar concrete mixture with the same geometry were tested under three point static loading and low velocity drop weight impact loading. load – displacement behavior, absorbed energy dissipation capacity, stiffnesses, failure modes of beam specimens were obtained and discuss...

Purpose: Fiber carbon is the most common material used in treating couch as it causes less beam attenuation than other materials. Beam attenuation replaces build-up region, reduces skin-sparing effect and causes target volume under dosage. In this study, we aimed to evaluate beam attenuation and variation of build-up region in 550 TxT radiotherapy couch.Materials and Methods: In this study, we ...

The present study is the first to analyze the dynamic response of a poroelastic beam subjected to a moving force. Moreover, the influences of attached mass-spring systems and non-ideal supports (with local movements in the supporting points or base due to the presence of factors such as gaps, unbalanced masses, and friction or seismic excitations) on the responses were investigated. Non-ideal s...

PURPOSE This aim of this paper is to revisit the parallel-beam/cone-beam or fan-beam/cone-beam imaging configuration, and to investigate whether this configuration has any advantages. METHODS Twenty years ago, it was suggested to simultaneously use a parallel-beam (or a fan-beam) collimator and a cone-beam collimator to acquire single photon emission computed tomography data. The motivation w...

this paper presents the high order frequency-amplitude relationship for nonlinear transversely vibrating beams with odd and even nonlinearities using homotopy perturbation method with an auxiliary term (hpmat). the governing equations of vibrating buckled beam, beam carrying an intermediate lumped mass and quintic nonlinear beam are investigated to exhibit the reliability and ability of the pro...

In this paper, the nonlinear conjugate map is applied based on the conjugate Hasofer-Lind and Rackwitz- Fiessler (CHL-RF) method to evaluate the reliability index using the first order reliability method of the embedded nanocomposite beam, which is made of a polymer reinforced with carbon nanotubes (CNTs). The structure is simulated with the Timoshenko beam model. The Mori-Tanaka model is appli...

Background: External beam radiation therapy is often administered to patients implanted with silicone gel breast prosthesis. The aim of this study was to investigate the influence of silicone gel breast prosthesis on photon dose distributions. In the event of recurrence, the oncologist may be forced to irradiate through the prosthetic device. To quantify the dose enhancement or reduction below ...