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It's shown suggested methods for diagnosing pathological processes in biological objects using a developed portable radiometric system with four gamma-ray detectors. Designed portable radiometric system was used to make 2D imaging of anatomical structures. The system can value pharmacokinetics in several points of wide area of interest at the patient body. In this study specially designed phantoms were used. Phantom models of the liver and blood circulation system were made to assay radiometric system. The construction concept and possible applications of the system in the practice of radionuclide diagnostic studies in vivo are presented. © 2018 Elsevier Ltd

A procedure has been developed for estimating the uniformity of anion vacancy distribution in TLD-500 detectors on the basis of anion-deficient corundum single crystals. Vacancy distribution topograms were constructed for TLD-500 detectors with different sensitivities to irradiation. Analysis of the topograms provided correlations between average anion vacancy concentrations and thermoluminescent (TL) yields in the main peak with a maximum at 450 K. To confirm the pattern of regularities, the effects of high-temperature annealing of TLD-500 samples in air at T = 1700 K were studied depending on its duration. Increasing the annealing time from 40 to 105 minutes was found to correlatedly reduce the anion vacancy concentrations and TL-yields in the basic and high-temperature peaks at 450 and 830 K, respectively. © Published under licence by IOP Publishing Ltd.

Phantoms of organs and biological systems are widely used for verification of radioisotope protocols. The construction and operation of the heart and circulation phantom is described. The present model was designed for experimental testing of multi-detector radiometric system, prototype of which was designed in Ural Federal University as an extension and alternative to Anger camera and single-photon-emission tomography radionuclide diagnostics. The model represents vital dynamic properties of the single-chamber pulsing heart and circulation, featuring adjustable heart rate, blood volume, ejection fraction and flowrate. The trial experiments were performed with 99m Tc-pertechnetate to obtain time-activity curves and the ejection fraction was thus measured basing on first-pass radio angiography technique. © Published under licence by IOP Publishing Ltd.

Optically stimulated luminescence (OSL), its mechanisms and the role of phototransfer effects in it have been comprehensively studied for strongly irradiated anion-deficient corundum with a high-temperature thermoluminescence (TL) peak at 830 K and without it. The fast component of the OSL kinetics in the samples was found to be due to the emptying of the main trap. The slow component was observed only in samples with the 830 K TL peak and was caused by the depletion of deep traps responsible for TL peaks in the range of 500 K

Multiphase nanopowders (NPs) and amorphous/amorphous-nanocrystalline coatings (A-NC) have been prepared by the evaporation of ceramic targets of Al2O3-Fe2O3 (0.1, 3, 5 Fe2O3 mass %) by a pulsed electron beam in vacuum. The specific surface area of NP Al2O3-Fe2O3 reached 277 m2/g. The α and γ phases Al2O3 and other nonidentified phases have been found in the composition of NP Al2O3-Fe2O3. All coatings contained an insignificant fraction of the crystalline γ phase. No secondary phases on the basis of iron have been revealed. According to transmission electron microscopy, the fine fraction of NP Al2O3-Fe2O3 consists of amorphous nanoparticles of an irregular and quasispherical shape no more than 10 nm in size which form agglomerates reaching 1.5 μm. A large fraction of NPs consists of crystal spherical nanoparticles with preferential sizes of about 10-20 nm. All NP Al2O3-Fe2O3 showed ferromagnetic behavior at room temperature. The maximum magnetic response has been established in NPs with a minimum iron content (1.1 mass %). The pulsed cathode luminescence spectra of coatings and NP Al2O3-Fe2O3 have been presented by a wide band in the wavelength range of 300-900 nm regardless of their phase composition. Phase transformations into NP AL2O3-1.1% Fe and coatings from undoped Al2O3 heated to 1400°C occur according to the following scheme: amorphous phase → γ → δ → θ → α, regardless of their initial phase composition. The threshold of thermal stability of the Γ phase in NPs and the coating of undoped Al2O3 does not exceed 830°C. For the first time, the increased thermo and optically stimulated luminescent response comparable with the response of the leading TLD-500K thermoluminescent dosimeter has been reached in A-NC coatings of undoped Al2O3. © 2013 Pleiades Publishing, Ltd.

The results of comparative investigations into the optically stimulated luminescence (OSL) of anion-defective corundum excited by radiation of blue and white light-emitting diodes (LEDs) are reported. The continuous-wave OSL (CW-OSL) measurements showed that the white LED (compared to the blue LED) and the chosen geometry allow the amplitude of the OSL response to increase by a factor of more than 40 and the dosimetric information readout time to decrease by a factor of 20. The effect of deep traps on the behavior of the CW-OSL curves of anion-defective corundum was studied. It was found that the filling of deep traps essentially increases the TL yield with a dosimetric peak at 450 K and the CW-OSL-yield under stimulation with blue and white LEDs. It was also found that this filling causes a considerable change in the shape of the OSL curve and the time parameters of the decay. © 2013 Elsevier Ltd. All rights reserved.