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In the present study, the normoxic polyacrylamide gelatin and tetrakis hydroxy methyl phosphoniun chloride (PAGAT) polymer gel dosimeters were synthesized with and without the presence of silver (Ag) nanoparticles. The amount of Ag nanoparticles varied from 1 to 3 ml with concentration 3.14 g/l, thus forming two types of PAGAT polymer gel dosimeters before irradiating them with 6 to 25 Gy produced by 1.25-MeV 60Co gamma rays. In this range, the predominant gamma ray interaction with matter is by Compton scattering effect, as the photoelectric absorption effect diminishes. MRI was employed when evaluating the polymerization of the dosimeters and the gray scale of the MRI film was determined via an optical densitometer. Subsequent analyses of optical densities revealed that the extent of polymerization increased with the increase in the absorbed dose, while the increase of penetration depth within the dosimeters has a reverse effect. Moreover, a significant increase in the optical density-dose response (11.82%) was noted for dosimeters containing 2 ml Ag nanoparticles.

Erbium-doped CaCu3Ti(4−x)ErxO12 (x = 0, 0.02, 0.1, 0.2, 0.5, 1.0)-(CCTEO) samples were synthesized by using the sol-gel method. The crystal structure did not change on doping with erbium; and it remained cubic when all the six compositions were studied. It was found that lattice parameter increased slightly with Erbium doping. AFM studies showed that the particle size of the CCTEO powder ranged from 52 to 97 nm. The surface morphology of the samples sintered at 1,040 °C in air for 3 h was observed using a high resolution scanning electron microscope. It showed that the grain size was in the range of 0.7-5 µm for these samples. Er doping has been shown to reduce the dielectric loss remarkably while maintaining a high dielectric constant. This result indicates that 0.02 mol% of Er dopant can be used to improve the dielectric properties (dielectric constant-164,000) of CaCu3Ti4O12.

In this study, the effects of different annealing temperatures on the structure and magnetic properties of Nd-Fe-B nanocomposite permanent magnetic alloys with nominal composition of Nd6Pr1Fe76B12Ti4C1Co3 have been investigated. Melt Spinning (one of the most predominant ribbon synthesize methods) with constant wheel speed of V = 25 m/s was employed to produce ribbons. As-spun ribbons were examined by using xray diffractometer (XRD) with Cu-Kα radiation and differential scanning calorimetry (DSC). The ribbons were annealed at different temperatures in order to extract the best magnetic properties. The XRD and electron microscopy technique results confirm that grains are in the size of less than 50 nm. In addition, optimum magnetic properties were obtained at 720°C annealed temperature.

In this study, Nanocrystalline Nd8Pr2Fe79-xCo5B6Alx (x= 0, 1, 2, 3) magnets were prepared by mechanical alloying method and respective heat treatment in a constant time and temperature. Afterward, the effects of the Al addition on the microstructure and magnetic properties of Nd-Fe-Co-B alloy were studied. The changes in the nanostructure and magnetic properties were examined by X-Ray diffraction (XRD), combined with Field Emission Scanning electron microscopy (FeSEM) and vibrating sample magnetometer (VSM). Addition of Al was found to be effective for improving the coercivity parameter and the hysteresis squareness in Nd–Fe–Co–B magnets without decreasing much the remanent magnetization.