4 research outputs found

    Effect of Gamma Irradiation on the Structural, Optical, Electrical, and Ferroelectric Characterizations of Bismuth-Modified Barium Titanate Ceramics

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    Materials with ferroelectric properties, low bandgap energies, high polarization, low loss, and thermal stability are essential for future solar-cell applications. Researchers have attempted to obtain such materials by using several approaches. In this vein, a novel approach is reported in this work using gamma ray irradiation. The effect of gamma radiation on the structural, optical, and ferroelectric characterizations of bismuth (Bi)-doped barium titanate (BaTiO3 (BT)), namely Ba0.95Bi0.05TiO3 ceramics (abbreviated as (Bi:BT)), was investigated. X-ray diffraction, structure refinement, and Raman study revealed the presence of a perovskite structure with a tetragonal phase in all investigated samples. Morphological study revealed a nonuniform grain size and some porosity. Gamma irradiation-induced combined effects were proved by a detailed analysis of bond lengths, bond angles, octahedral distortions, oxygen vacancies, and charge compensations. Electron paramagnetic resonance (EPR) study gave direct evidence of oxygen vacancies in the irradiated samples. After gamma irradiation, UV–vis study indicated a decrease in the bandgap from 3.14 to 2.80 eV and a significant increase in visible light absorption. Cole–Cole plots confirm as an increase in gamma-ray dose results in higher levels of electron hopping. Study of the P–E hysteresis loop demonstrated that ferroelectric properties could be maintained after gamma irradiation, with a slight decrease in remnant polarization. The behaviour of the P–E was correlated with increasing gamma dose in the investigated ceramics, demonstrating a strong gamma dependence in the loops’ profile. We guess that the present approach may be a promising technique for enhancing the multifunctionality of electronic devices

    Effect of gamma rays irradiation in the structure, optical, and electrical properties of samarium doped bismuth titanate ceramics

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    To fully understand how irradiation affects the structural, optical, dielectric, and ferroelectric characteristics of BSmT ceramics, a systematic study is needed. The characteristics of BSmT ceramics were minimally affected by different gamma doses, and they demonstrated high stability against gamma irradiation, which offers considerable promise for their use in nuclear reactor technology

    Identification of Activation Isotopes in a CS-30 Cyclotron Vault

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    A CS-30 cyclotron has been in operation at King Faisal Specialist Hospital and Research Center (KFSHRC) since 1982. The CS-30 cyclotron has been used to produce medical radioisotopes for positron emission tomography (PET) and single-photon emission computed tomography (SPECT). Some of the nuclear reactions of radionuclide production are associated with the intense release of a wide range of fast neutrons. In this work, we investigated the radionuclides produced from neutron interactions with the cyclotron facility walls. Activation isotopes were determined by performing gamma ray spectrometry utilizing a high-purity germanium (HPGe) detector. The major radionuclides found were 152Eu, 154Eu, 134Cs, 65Zn and 60Co. Activation isotope accumulation had increased the dose rate inside the facility. The surface dose rates were measured at all of the surrounding walls. The maximum surface dose rate was found to be 1.2 µSv/h, which is much lower than the permissible occupational exposure of 15 µSv/h based daily 5 work hours
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