Synthesis of Gd-DTPA Carborane-Containing Compound and Its Immobilization on Iron Oxide Nanoparticles for Potential Application in Neutron Capture Therapy.

Cancer is one of the leading causes of global mortality, and its incidence is increasing annually. Neutron capture therapy (NCT) is a unique anticancer modality capable of selectively eliminating tumor cells within normal tissues. The development of accelerator-based, clinically mountable neutron sources has stimulated a worldwide search for new, more effective compounds for NCT. We synthesized magnetic iron oxide nanoparticles (NPs) that concurrently incorporate boron and gadolinium, potentially enhancing the effectiveness of NCT. These magnetic nanoparticles underwent sequential modifications through silane polycondensation and allylamine graft polymerization, enabling the creation of functional amino groups on their surface. Characterization was performed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray (EDX), dynamic light scattering (DLS), thermal gravimetric analysis (TGA), and transmission electron microscopy (TEM). ICP-AES measurements indicated that boron (B) content in the NPs reached 3.56 ppm/mg, while gadolinium (Gd) averaged 0.26 ppm/mg. Gadolinium desorption was observed within 4 h, with a peak rate of 61.74%. The biocompatibility of the NPs was confirmed through their relatively low cytotoxicity and sufficient cellular tolerability. Using NPs at non-toxic concentrations, we obtained B accumulation of up to 5.724 × 1010 atoms per cell, sufficient for successful NCT. Although limited by its content in the NP composition, the Gd amount may also contribute to NCT along with its diagnostic properties. Further development of the NPs is ongoing, focusing on increasing the boron and gadolinium content and creating active tumor targeting.

Preparation and application of stimuli-responsive PET TeMs: RAFT graft block copolymerisation of styrene and acrylic acid for the separation of water-oil emulsions.

Stimuli-responsive membranes play an important role in the fields of biomedicine, food and chemical industries, and environmental applications, including separation of water-oil emulsions. In this study, we present a method to fabricate pH-sensitive membranes using UV-initiated RAFT graft copolymerization of styrene (ST) and acrylic acid (AA) on poly(ethylene terephthalate) (PET) track-etched membranes (TeMs). The optimization of polymerization conditions led to successful grafting of polystyrene (PS) and poly(acrylic acid) (PAA) onto PET TeMs, resulting in membranes with stable hydrophobicity and pH change responsiveness. The membranes show a contact angle of 65° in basic environments (pH 9) and 97° in acidic environments (pH 2). The membranes were characterized by atomic force microscopy (AFM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), thermogravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR), contact angle (CA) methods. The PET TeMs-g-PS-g-PAA exhibited good performance in separating water-oil emulsions with a high efficiency of more than 90% and flux for direct chloroform-water 2500 L m-2 h-1 and reverse emulsions of benzene-water 1700 L m-2 h-1. This method of preparing stimuli-responsive membranes with controlled wettability and responsiveness to environmental pH provides versatility in their use in separating two types of emulsions: direct and reverse.

Effect of hydrophobized PET TeMs membrane pore-size on saline water treatment by direct contact membrane distillation.

This paper describes the desalination process by membrane distillation (MD) using track-etched membranes (TeMs). Hydrophobic track-etched membranes based on poly(ethylene terephthalate) (PET TeMs) with pore diameters from 700 to 1300 nm were prepared by UV-initiated graft polymerization of lauryl methacrylate (LMA) inside the nanochannels. Modified PET TeMs were investigated by Fourier transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and contact wetting angle (CA) measurements. Hydrophobic PET TeMs were tested for treating saline solutions of different concentrations by the direct contact membrane distillation (DCMD) method. The influence of membrane pore diameter and salt solution concentration on the water flux and rejection degree were investigated. Membranes with CA 94 ± 4° were tested in the direct contact membrane distillation (DCMD) of 7.5-30 g L-1 saline solution. Hydrophobic membranes with large pore sizes showed water fluxes in the range of 1.88 to 11.70 kg m-2 h-1 with salt rejection values of up to 91.4%.

Study of the Relationship between Changes in the Structural, Optical, and Strength Properties of AlN Ceramics Subjected to Irradiation with Heavy Xe23+ Ions.

The purpose of this study is to comprehensively analyze the influence of different fluences of irradiation with Xe23+ heavy ions on alterations in the structural, optical, and strength properties of AlN ceramics and to establish a connection between structural distortions and alterations in the optical and mechanical properties of the ceramics. X-ray diffraction, UV-Vis and Raman spectroscopy, and indentation and single-compression methods were used as research methods. During the study, it was demonstrated that at low irradiation fluences, the main role in the changes in the properties of the AlN ceramics is played by effects related to changes in their optical properties and a fundamental absorption edge shift, which characterizes changes in the electronic properties of the ceramics (changes in the distribution of electron density). A study of the variations in the optical properties of the examined samples in relation to the irradiation fluence showed that when the fluence surpasses 5 × 1011 ion/cm2, an extra-spectral absorption band emerges within the range of 3.38-3.40 eV. This band is distinctive for the creation of vacancy ON-VAl complexes within the damaged layer's structure. The presence of these complexes signifies structural deformations and the accumulation of defective inclusions within the damaged layer. An analysis of changes in the parameters of the crystal lattice showed that structural distortions in the damaged layer are due to the accumulation of tensile residual mechanical stresses, an increase in the concentration of which leads to the swelling and destruction of the damaged layer. Some correlations between the mechanical properties of ceramics and the irradiation fluence indicate the ceramics' remarkable resistance to radiation-induced brittleness and weakening. These effects become apparent only when structural damage accumulates, resulting in the swelling of the crystal lattice exceeding 2.5-3%.

Insight into What Is inside Swift Heavy Ion Latent Tracks in PET Film.

We present here a novel experimental study of changes after contact electrification in the optical transmission spectra of samples of both pristine and irradiated PET film treated with Kr+15 ions of energy of 1.75 MeV and a fluence of 3 × 1010 cm2. We used a non-standard electrification scheme for injecting electrons into the film by applying negative electrodes to both its surfaces and using the positively charged inner regions of the film itself as the positive electrode. Electrification led to a decrease in the intensity of the internal electric fields for both samples and a hypsochromic (blue) shift in their spectra. For the irradiated PET sample, electrification resulted in a Gaussian modulation of its optical properties in the photon energy range 2.3-3.6 eV. We associate this Gaussian modulation with the partial decay of non-covalent extended conjugated systems that were formed under the influence of the residual radial electric field of the SHI latent tracks. Our studies lead us to suggest the latent track in the PET film can be considered as a variband material in the radial direction. Consideration of our results along with other published experimental results leads us to conclude that these can all be consistently understood by taking into account both the swift and slow electrons produced by SHI irradiation, and that it appears that the core of a latent track is negatively charged, and the periphery is positively charged.

Effect of 160 MeV Xenon Ion Irradiation on the Tribological Properties and Crystal Structure of 100Cr6 Bearing Steel.

This is the first study ever to show the impact of high-energy 160 MeV xenon ion irradiation on the properties of 100Cr6 bearing steel. The projected range (Rp) of xenon ions is 8.2 µm. Fluence-dependent variations in the coefficient of friction and wear of the 100Cr6 steel material have been observed. These changes correlate with shifts in the crystal lattice constant and variations in the oxygen, carbon, and iron content in the wear track. Fluence-dependent changes in these parameters have been observed for the first time. Irradiation reduces stresses in the crystal lattice, leading to crystallite size increase. The modifications in the properties of 100Cr6 steel result from radiation-induced defects caused by electronic ion stopping. The degree of these modifications depends on the applied irradiation fluence. Furthermore, the use of a higher irradiation fluence value appears to mitigate the effects produced by a lower fluence.

Study of The Gas-Swelling Mechanisms in Silicon Carbide Ceramics under High-Temperature Irradiation with Helium Ions.

The purpose of this work is to simulate the processes of gaseous swelling in SiC ceramics as well as the associated changes in strength and thermophysical properties under high-temperature irradiation with helium ions. The choices of irradiation conditions (irradiation temperatures of 700 and 1000 K) and irradiation fluences (1015-1018 ion/cm2) are based on the possibilities of modeling the processes of destructive changes in the near-surface layer as a result of the accumulation of gas-filled inclusions during high-dose irradiation. During this study, it was found that an increase in the irradiation temperature of the samples from 700 to 1000 K leads to a decrease in the resistance to gas swelling, since with the temperature increase, the mobility of implanted helium in the near-surface layer grows, which results in an increase in the size of gas-filled bubbles and, as a result, accelerated destruction of the damaged layer. It has been established that in the case of irradiation at 700 K, the critical fluence for swelling associated with the formation of visible gas-filled bubbles on the surface is 5 × 1017 ion/cm2, while for samples irradiated at a temperature of 1000 K, the formation of gas-filled bubbles is observed at a fluence of 1017 ion/cm2. Measurements of the thermal conductivity coefficient showed that the formation of gas-filled bubbles leads to a sharp deterioration in heat transfer processes, which indicates that the created defective inclusions prevent phonon heat transfer. Changes in the strength characteristics showed that a decrease in hardness occurs throughout the entire depth of the damaged ceramic layer. However, with a rise in the irradiation fluence above 1017 ion/cm2, a slight damaged layer thickness growth associated with diffusion processes of helium implantation into the near-surface layer is observed. The relevance of this study consists in obtaining new data on the stability of the strength and thermophysical parameters of SiC ceramics in the case of helium accumulation and its subsequent radiation-induced evolution in the case of irradiation at temperatures of 700 and 1000 K. The data obtained during the experimental work on changes in the properties of ceramics will make it possible to determine the potential limits of their applicability in the case of operation under extreme conditions at elevated temperatures in the future.

Study of the Influence of the Irradiation Flux Density on the Formation of a Defect Structure in AlN in the Case of the Effect of Overlapping of the Heavy Ion Motion Trajectories in the Near-Surface Layer.

The aim of this paper is to test the previously stated hypothesis and several experimental facts about the effect of the ion flux or ion beam current under irradiation with heavy ions on the radiation damage formation in the ceramic near-surface layer and their concentration. The hypothesis is that, when considering the possibilities of using ion irradiation (usually with heavy ions) for radiation damage simulation at a given depth, comparable to neutron irradiation, it is necessary to consider the rate factor for the set of atomic displacements and their accumulation. Using the methods of X-ray diffraction analysis, Raman and UV-Vis spectroscopy, alongside photoluminescence, the mechanisms of defect formation in the damaged layer were studied by varying the current of the Xe23+ ion beam with an energy of 230 MeV. As a result of the experimental data obtained, it was found that, with the ion beam current elevation upon the irradiation of nitride ceramics (AlN) with heavy Xe23+ ions, structural changes have a pronounced dependence on the damage accumulation rate. At the same time, the variation of the ion beam current affects the main mechanisms of defect formation in the near-surface layer. It has been found that at high values of flux ions, the dominant mechanism in damage to the surface layer is the mechanism of the formation of vacancy defects associated with the replacement of nitrogen atoms by oxygen atoms, as well as the formation of ON-VAl complexes.

Study of the Aid Effect of CuO-TiO2-Nb2O5 on the Dielectric and Structural Properties of Alumina Ceramics.

The aim of this work is to study the structural, dielectric, and mechanical properties of aluminum oxide ceramics with the triple sintering additive 4CuO-TiO2-2Nb2O5. With an increase in sintering temperature from 1050 to 1500 °C, the average grain size and the microhardness value at a load of 100 N (HV0.1) increased with increasing density. It has been shown that at a sintering temperature of 1300 °C, the addition of a 4CuO-TiO2-2Nb2O5 additive increases the low-frequency permittivity (2-500 Hz) in alumina ceramic by more than an order of magnitude due to the presence of a quadruple perovskite phase. At the same time, the density of such ceramics reached 89% of the theoretical density of α-Al2O3, and the microhardness value HV0.1 was 1344. It was observed that the introduction of 5 wt.% 4CuO-TiO2-2Nb2O5 in the raw mixture remarkably increases values of shrinkage and density of sintered ceramics. Overall, the results of this work confirmed that introducing the 4CuO-TiO2-2Nb2O5 sintering additive in the standard solid-phase ceramics route can significantly reduce the processing temperature of alumina ceramics, even when micron-sized powders are used as a starting material. The obtained samples demonstrated the potential of α-Al2O3 with the triple additive in such applications as electronics, microwave technology, and nuclear power engineering.

Synthesis and Structural and Strength Properties of xLi2ZrO3-(1-x)MgO Ceramics-Materials for Blankets.

The article considers the effect of doping with magnesium oxide (MgO) on changes in the properties of lithium-containing ceramics based on lithium metazirconate (Li2ZrO3). There is interest in this type of ceramics on account of their prospects for application in tritium production in thermonuclear power engineering, as well as several other applications related to alternative energy sources. During the investigations undertaken, it was found that variation in the MgO dopant concentration above 0.10-0.15 mol resulted in the formation of impurity inclusions in the ceramic structure in the form of a MgLi2ZrO4 phase, the presence of which resulted in a rise in the density of the ceramics, along with elevation in resistance to external influences. Moreover, during experimental work on the study of the thermal stability of the ceramics to external influences, it was found that the formation of two-phase ceramics resulted in growth in the preservation of stable strength properties during high-temperature cyclic tests. The decrease in strength characteristics was observed to be less than 1%.

Study of the Kinetics of Radiation Damage in CeO2 Ceramics upon Irradiation with Heavy Ions.

In this work, the effect of irradiation with heavy Kr15+ and Xe22+ ions on the change in the structural and strength properties of CeO2 microstructural ceramics, which is one of the candidates for inert matrix materials for dispersed nuclear fuel, is considered. Irradiation with heavy Kr15+ and Xe22+ ions was chosen to determine the possibility of simulation of radiation damage comparable to the action of fission fragments, as well as neutron radiation, considering damage accumulation at a given depth of the near-surface layer. During the research, it was found that the main changes in the structural properties with an increase in the irradiation fluence are associated with the crystal lattice deformation distortions and the consequent radiation damage accumulation in the surface layer, and its swelling. Evaluation of the effect of gaseous swelling caused by the radiation damage accumulation showed that a variation in the ion type during irradiation results in a growth in the value of swelling and destruction of the near-surface layer with the accumulation of deformation distortions. Results of the strength variation demonstrated that the most intense decrease in the near-surface layer hardness is observed when the fluence reaches more than 1013-1014 ion/cm2, which is typical for the effect of overlapping radiation damage in the material.

e-Beam and γ-rays Induced Synthesis and Catalytic Properties of Copper Nanoclusters-Deposited Composite Track-Etched Membranes.

Effective removal of toxic inorganic and organic pollutants is one of the current leading challenges of wastewater treatment. In this study, the decomposition of methylene blue (MB) under UV light irradiation was investigated in the presence of copper nanoclusters (NCs)-deposited polyethylene terephthalate (PET) track-etched hybrid membranes. PET track-etched membranes (TeMs) with an average pore size of ~400 nm were grafted by functional acrylic acid (AA) monomer under electron beam irradiation after oxidation with H2O2/UV system. The radiation dose varied between 46 and 200 kGy. For the deposition of copper NCs, poly(acrylic acid) (PAA)-grafted membranes saturated with Cu(II) ions were irradiated either by electron beam or γ-rays to obtain copper-based NCs for the catalytic degradation of MB. Irradiation to 100 kGy with accelerated electrons resulted in the formation of small and uniform copper hydroxide (Cu(OH)2) nanoparticles homogeneously distributed over the entire volume of the template. On the other hand, irradiation under γ-rays yielded composites with copper NCs with a high degree of crystallinity. However, the size of the deposited NCs obtained by γ-irradiation was not uniform. Nanoparticles with the highest uniformity were obtained at 150 kGy dose. Detailed analysis by X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed the loading of copper nanoparticles with an average size of 100 nm on the inner walls of nanochannels and on the surface of PET TeMs. Under UV light irradiation, composite membranes loaded with NCs exhibited high photocatalytic activity. It was determined that the highest catalytic activity was observed in the presence of Cu(OH)2@PET-g-PAA membrane obtained at 250 kGy. More than 91.9% of the initial dye was degraded when this hybrid membrane was employed for 180 min, while only 83.9% of MB was degraded under UV light using Cu@PET-g-PAA membrane. Cu(OH)2@PET-g-PAA membranes obtained under electron beam irradiation demonstrated a higher photocatalytic activity compared to Cu@PET-g-PAA membranes attained by γ-rays.

Environmentally friendly loading of palladium nanoparticles on nanoporous PET track-etched membranes grafted by poly(1-vinyl-2-pyrrolidone) via RAFT polymerization for the photocatalytic degradation of metronidazole.

Nanoporous track-etched membranes (TeMs) are highly versatile materials that have shown promise in various applications such as filtration, separation, adsorption, and catalysis due to their mechanical integrity and high surface area. The performance of TeMs as catalysts for removing toxic pollutants is greatly influenced by the pore diameter, density, and functionalization of the nanochannels. In this study, the synthesis of functionalized poly(ethylene terephthalate) (PET) TeMs with Pd nanoparticles (NPs) as catalysts for the photodegradation of the antibiotic metronidazole (MTZ) was methodically investigated and their catalytic activity under UV irradiation was compared. Before loading of the Pd NPs, the surface and nanopore walls of the PET TeMs were grafted by poly(1-vinyl-2-pyrrolidone) (PVP) via UV-initiated reversible addition fragmentation chain transfer (RAFT)-mediated graft copolymerization. The use of RAFT polymerization allowed for precise control over the degree of grafting and graft lengths within the nanochannels of PVP grafted PET TeMs (PVP-g-PET). Pd NPs were then loaded onto PVP-g-PET using several environmentally friendly reducing agents such as ascorbic acid, sodium borohydride and a plant extract. In addition, a conventional thermal reduction technique was also applied for the reduction of the Pd NPs. The grafting process created a surface with high-sorption capacity for MTZ and also high stabilizing effect for Pd NPs due to the functional PVP chains on the PET substrate. The structure and composition of the composite membranes were elucidated by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, thermogravimetry, contact angle measurements and energy dispersive X-ray (EDX), X-ray photoelectron (XPS) and Fourier transform infra-red (FTIR) spectroscopies. The effects of different types of reducing agents, pH, the amount of loaded catalyst and MTZ concentration on the MTZ catalytic degradation efficiency of the obtained composites were investigated. The efficiency of the catalyst prepared in the presence of ascorbic acid was superior to the others (89.86% removal at 30 mg L-1 of MTZ). Maximum removal of MTZ was observed at the natural pH (6.5) of the MTZ solution at a concentration of 30 mg per L MTZ. The removal efficiency was decreased by increasing the catalyst dosage and the initial MTZ concentration. The reaction rate constant was reduced from 0.0144 to 0.0096 min-1 by increasing the MTZ concentration from 20 to 50 mg L-1. The photocatalyst revealed remarkable photocatalytic activity even after 10 consecutive cycles.

Study of the Mechanisms of Radiation Softening and Swelling upon Irradiation of TiTaNbV Alloys with He2+ Ions with an Energy of 40 keV.

This paper presents simulation results of the ionization losses of incident He2+ ions with an energy of 40 keV during the passage of incident ions in the near-surface layer of alloys based on TiTaNbV with a variation of alloy components. For comparison, data on the ionization losses of incident He2+ ions in pure niobium, followed by the addition of vanadium, tantalum, and titanium to the alloy in equal stoichiometric proportions, are presented. With the use of indentation methods, the dependences of the change in the strength properties of the near-surface layer of alloys were determined. It was established that the addition of Ti to the composition of the alloy leads to an increase in resistance to crack resistance under high-dose irradiation, as well as a decrease in the degree of swelling of the near-surface layer. During tests on the thermal stability of irradiated samples, it was found that swelling and degradation of the near-surface layer of pure niobium affects the rate of oxidation and subsequent degradation, while for high-entropy alloys, an increase in the number of alloy components leads to an increase in resistance to destruction.

Eco-Friendly Electroless Template Synthesis of Cu-Based Composite Track-Etched Membranes for Sorption Removal of Lead(II) Ions.

This paper reports the synthesis of composite track-etched membranes (TeMs) modified with electrolessly deposited copper microtubules using copper deposition baths based on environmentally friendly and non-toxic reducing agents (ascorbic acid (Asc), glyoxylic acid (Gly), and dimethylamine borane (DMAB)), and comparative testing of their lead(II) ion removal capacity via batch adsorption experiments. The structure and composition of the composites were investigated by X-ray diffraction technique and scanning electron and atomic force microscopies. The optimal conditions for copper electroless plating were determined. The adsorption kinetics followed a pseudo-second-order kinetic model, which indicates that adsorption is controlled by the chemisorption process. A comparative study was conducted on the applicability of the Langmuir, Freundlich, and Dubinin-Radushkevich adsorption models to define the equilibrium isotherms and the isotherm constants for the prepared composite TeMs. Based on the regression coefficients R2, it has been shown that the Freundlich model better describes the experimental data of the composite TeMs on the adsorption of lead(II) ions.

Stimuli-Responsive Track-Etched Membranes for Separation of Water-Oil Emulsions.

In this work, we have developed a method for the preparation of pH-responsive track-etched membranes (TeMs) based on poly(ethylene terephthalate) (PET) with pore diameters of 2.0 ± 0.1 µm of cylindrical shape by RAFT block copolymerization of styrene (ST) and 4-vinylpyridine (4-VP) to be used in the separation of water-oil emulsions. The influence of the monomer concentration (1-4 vol%), the molar ratio of RAFT agent: initiator (1:2-1:100) and the grafting time (30-120 min) on the contact angle (CA) was studied. The optimal conditions for ST and 4-VP grafting were found. The obtained membranes showed pH-responsive properties: at pH 7-9, the membrane was hydrophobic with a CA of 95°; at pH 2, the CA decreased to 52°, which was due to the protonated grafted layer of poly-4-vinylpyridine (P4VP), which had an isoelectric point of pI = 3.2. The obtained membranes with controlled hydrophobic-hydrophilic properties were tested by separating the direct and reverse "oil-water" emulsions. The stability of the hydrophobic membrane was studied for 8 cycles. The degree of purification was in the range of 95-100%.

Synthesis and Characterization of the Properties of (1-x)Si3N4-xAl2O3 Ceramics with Variation of the Components.

The aim of this paper is to study the effect of variation in the component ratio of (1-x)Si3N4-xAl2O3 ceramics on the phase composition, strength and thermal properties of ceramics. To obtain ceramics and their further study, the solid-phase synthesis method combined with thermal annealing of samples at a temperature of 1500 °C typical for the initialization of phase transformation processes was used. The relevance and novelty of this study lies in obtaining new data on the processes of phase transformations with a variation in the composition of ceramics, as well as determining the effect of the phase composition on the resistance of ceramics to external influences. According to X-ray phase analysis data, it was found that an increase in the Si3N4 concentration in the composition of ceramics leads to a partial displacement of the tetragonal phase of SiO2 and Al2(SiO4)O and an increase in the contribution of Si3N4. Evaluation of the optical properties of the synthesized ceramics depending on the ratio of the components showed that the formation of the Si3N4 phase leads to an increase in the band gap and the absorbing ability of the ceramics due to the formation of additional absorption bands from 3.7-3.8 eV. Analysis of the strength dependences showed that an increase in the contribution of the Si3N4 phase with subsequent displacement of the oxide phases leads to a strengthening of the ceramic by more than 15-20%. At the same time, it was found that a change in the phase ratio leads to the hardening of ceramics, as well as an increase in crack resistance.

Investigation of the Effect of PbO Doping on Telluride Glass Ceramics as a Potential Material for Gamma Radiation Shielding.

The purpose of this paper is to study the effect of PbO doping of multicomponent composite glass-like ceramics based on TeO2, WO3, Bi2O3, MoO3, and SiO2, which are one of the promising materials for gamma radiation shielding. According to X-ray diffraction data, it was found that the PbO dopant concentration increase from 0.10 to 0.20-0.25 mol results in the initialization of the phase transformation and structural ordering processes, which are expressed in the formation of SiO2 and PbWO4 phases, and the crystallinity degree growth. An analysis of the optical properties showed that a change in the ratio of the contributions of the amorphous and ordered fractions leads to the optical density increase and the band gap alteration, as well as a variation in the optical characteristics. During the study of the strength and mechanical properties of the synthesized ceramics, depending on the dopant concentration, it was found that when inclusions in the form of PbWO4 are formed in the structure, the strength characteristics increase by 70-80% compared to the initial data, which indicates the doping efficiency and a rise in the mechanical strength of ceramics to external influences. During evaluation of the shielding protective characteristics of the synthesized ceramics, it was revealed that the formation of PbWO4 in the structure results in a rise in the high-energy gamma ray absorption efficiency.

Enhancement of Luminescence of PET Films after Swift Heavy Ion Irradiation.

The novelty of the study is that the ordering that occurs in a PET film under the action of SHI irradiation manifests itself as an increase in the integral intensity of intrinsic luminescence. The Urbach behaviour of the red shift of the absorption edge is used as a baseline for further analysis of experimental optical transmission spectra of PET films irradiated by swift heavy ions (SHI) previously published by the authors. Negative deviations of the experimental spectra from the Urbach baseline in the visible and UV parts of the spectrum are attributed to enhanced by SHI irradiation intrinsic luminescence. The observed dependence of the integral intensity of luminescence of irradiated PET films on the SHI fluence and ion charge provides further confirmation of the presence of SHI-induced ordering of the molecular structure in SHI latent tracks.

Evaluation of the Influence of Grain Sizes of Nanostructured WO3 Ceramics on the Resistance to Radiation-Induced Softening.

The main purpose of this study is to test a hypothesis about the effect of grain size on the resistance to destruction and changes in the strength and mechanical properties of oxide ceramics subjected to irradiation. WO3 powders were chosen as objects of study, which have a number of unique properties that meet the requirements for their use as a basis for inert matrices of dispersed nuclear fuel. The grain-size variation in WO3 ceramics was investigated by mechanochemical grinding of powders with different grinding speeds. Grinding conditions were experimentally selected to obtain powders with a high degree of size homogeneity, which were used for further research. During evaluation of the strength properties, it was found that a decrease in the grain size leads to an increase in the crack resistance, as well as the hardness of ceramics. The increase in strength properties can be explained by an increase in the dislocation density and the volume contribution of grain boundaries, which lead to hardening and an increase in resistance. During determination of the radiation damage resistance, it was found that a decrease in grain size to 50-70 nm leads to a decrease in the degree of radiation damage and the preservation of the resistance of irradiated ceramics to destruction and cracking.