Background: Polymer gel dosimeters combined with magnetic resonance imaging (MRI) can be used for dose verification of advanced radiation therapy techniques. However, the uncertainty of dose map measured by gel dosimeter should be known. The purpose of this study is to investigate the uncertainty related to calibration curve and MRI protocol for MAGIC (Methacrylic and Ascorbic acid in Gelatin I...

A polymer gel (ferrogel) is an assembly of ferromagnetic nanoparticles embeded in gel. In the ferrogel, the finely distributed magnetic particles are suspended in the swelling liquid and forma flexible matrix due to adhesive forces. The present paper describes an electric and acoustic study of magnetic field sensitive poly (dimethyl siloxane) ferrogel. The results showed hysteresis of acoustic ...

This work assesses the overall reproducibility and accuracy of an x-ray computed tomography (CT) polymer gel dosimetry (PGD) system using a N-isopropylacrylamide (NIPAM) based polymer gel and investigated what effects the use of generic, inter-batch, and intra-batch gel calibration have on dosimetric and spatial accuracy. Overall excellent spatial and dosimetric accuracy was found with this sys...

We have investigated rapidly thermo-responsive NIPA gel containing polymer surfactant PMDP (NIPA-PMDP gel) as a potential drug carrier using (+)-l-ascorbic acid as a model drug. In the NIPA-PMDP gel system micelles of polymer surfactant PMDP are trapped by the entanglement of polymer chains inside the gel networks. Therefore, in principle the gel system tightly stores targeted drug in the micel...

This study linked the chemical potential change to high specific filtration resistance (SFR) of gel layer, and then proposed a novel membrane fouling mechanism regarding gel layer filtration, namely, Flory-Huggins based filtration mechanism. A mathematical model for this mechanism was theoretically deduced. Agar was used as a model polymer for gel formation. Simulation of the mathematical model...

Zoogloea ramigera 115 synthesized large amounts of matrix polymer from fructose, galactose, glucose, lactose, mannose, soluble starch, and sucrose when these carbohydrates were used as supplements to a chemically defined medium. All of them supported polymer synthesis to the extent that cultures thickened to a gel. Concentration of carbohydrate nutrients in the range 0.5 to 2.0% was not a criti...

Introduction: Computed tomography (CT) has numerous applications in clinical procedures but its main problem is its high radiation dose to the patients compared to other imaging modalities using x-ray. CT delivers approximately high doses to the nearby tissues due to the scattering effect, fan beam (beam divergence) and limited collimator efficiency. The radiation dose from multi-slice scanners...

In this paper, taking account of the major physical and chemical mechanisms, such as: for polymer, shearing propertypermeability reduction, adsorption, inaccessible porous volumes, for gel, gelation speed, water viscosity changing with gel, permeability reduction, adsorption and retention in reservoir rocks, a three-dimensional, three-phase (oleic, vapor, aqueous) and six-component mathematical...

Abstract Mefenamic acid is a nonsteroidal anti-inflammatory drug (NSAID) that has analgesic,anti-infammatory and antipyretic actions. It is used to relieve mild to moderate pains. Solid-phase extraction of mefenamic acid by a polymer grafted to silica gel is reported . Poly allyl glycidyl ether/iminodiacetic acid-co-N, N-dimethylacrylamide was synthesized and grafted to silica gel and was used ...