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The work presents the changes in the structural and conductive properties of Ni nanostructures. B2+, Ca5+, Fe7+ ions were used as the bombarding beams. Fluence irradiation constitutes 1010, 1011 и 5 × 1011 ion/cm2. The use of ions B2+, Ca5+, Fe7+ allows to simulate the effects of irradiation with different energy losses, as well as the course of the process of defects formation in structures. It has been established that in the samples irradiated with B2+ and Ca5+ ions, the main structural changes are associated with amorphization or texture reorientation, and for samples irradiated with Fe7+ ions, the formation of low intense peaks characteristic of FeNi is observed. It has been established that an increase in the degree of crystallinity indicates a positive effect of calcium ions on the crystal structure, which consists in the partial annealing of defects and the removal of stresses and distortions in the crystal lattice. A slight decrease in the degree of crystallinity during irradiation with iron ions can be explained by the processes of implantation and knocking out of nickel atoms from lattice sites, which leads to the formation of impurity inclusions in the form of the FeNi phase, the content of which increases with irradiation fluence. The formation in the structure of amorphous inclusions and partial destruction of the walls of nanotubes under the action of irradiation with boron ions leads to a sharp decrease in the degree of crystallinity and conductive properties of nanotubes.

By template synthesis method nickel nanotubes with diameter of 400 nm and length of 12 μm were produced in the pores of PET template. The nanotubes were modified by irradiation with carbon ions with energy of 28 MeV and a dose of 5 × 1011 cm-2. To ensure the maximum efficiency of nanostructures modification process, energy of irradiation was decided by using of SRIM software. Based on SRIM simulation of carbon ions interaction with Ni nanotubes, the areas on which effect of high energy ions will maximum were predicted. A comparative analysis of nanostructures before and after irradiation was carried out by scanning electron microscopy. The maximum change in nanotubes morphology, in the form of destruction of walls, was appeared at a distance of about 10 μm from the start point of C3+ ions track inside the nanotubes. A substantiation of reason of wall degradation in this area was proposed. © 2019 Elsevier Ltd. Horizon 2020 Framework Programme, H2020: 778308.

The use of nitride ceramics, in particular AlN, as structural materials for nuclear power is primarily limited by their resistance to swelling and hydrogenation processes due to the accumulation of poorly soluble helium and hydrogen ions in the structure of the surface layer. In this regard, research in this area is of great importance not only from a fundamental point of view, but also practical, since any new data on radiation resistance can make a great contribution to the development of the theory of resistance to radiation influences of structural materials of a new generation. This work is devoted to a systematic study and comparative analysis of the dynamics of radiation damage during high-dose irradiation with protons and helium ions in nitride ceramics, which have great potential for use as structural materials for GenIV reactors. The choice of irradiation doses of 1 &times, 1017&ndash, 5 &times, 1017 ion/cm2 is due to the possibility of modeling the processes of radiation damage characteristic of displacements of 10&ndash, 50 dpa. During the study, the dependences of the change in the dielectric and conductive characteristics of nitride ceramics depending on the radiation dose, as well as on the type of ions, were established. The kinetics of degradation and accelerated aging was determined depending on the type of exposure. The mechanical and strength properties of ceramics were determined.

The paper presents the results of changes in the structural characteristics, and the degree of texturing of FeNi nanostructures close in composition to permalloy compounds as a result of directed modification by gamma radiation with an energy of 1.35 MeV and doses from 100 to 500 kGy. The choices of energy and radiation doses were due to the need to modify the structural properties, which consisted of annealing the point defects that occurred during the synthesis along the entire length of the nanotubes. The initial FeNi nanostructures were polycrystalline nanotubes of anisotropic crystallite orientation, obtained by electrochemical deposition. The study found that exposure to gamma rays led to fewer defects in the structure, and reorientation of crystallites, and at doses above 300 kGy, the presence of one selected texture direction (111) in the structure. During tests of the corrosion resistance of synthesized and modified nanostructures in a PBS solution at various temperatures, it was found that exposure to gamma rays led to a significant decrease in the rate of degradation of nanotubes and an increase in the potential life of up to 20 days. It was established that at the first stage of testing, the degradation of nanostructures is accompanied by the formation of oxide inclusions, which subsequently lead to the formation of pitting corrosion and subsequent partial or complete destruction of the nanostructures. It is shown that gamma radiation is promising not only for targeted modification of nanostructures and increasing resistance to degradation, but also for increasing the rate of catalytic reactions of the PNA-PPD type. © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Ministry of Education and Science of the Republic of Kazakhstan Funding: This study was funded by the Ministry of Education and Science of the Republic of Kazakhstan (grant AP05133578).

In this paper, we present the results of liquid low-level radioactive wastes (LLLRW) treatment by direct contact membrane distillation (DCMD) using polyethylene terephthalate (PET) track-etched membranes (TeMs). PET TeMs were modified by styrene and triethoxyvinylsilane (TEVS) using UV-induced grafting. Modification led to increase in the contact angle to 99° of PET TeMs (pore size from 150 to 300 nm). Hydrophobic PET TeMs were investigated by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), goniometric analysis, gas permeability test, liquid entry presser (LEP) analysis and scanning electron microscope (SEM). Prepared membranes were tested in treatment of LLLRW by DCMD. The influence of pore size on water flux and rejection degree was studied. Rejection degree was evaluated by conductometry and atomic emission methods. Decontamination factors (evaluated by gamma-ray spectroscopy) for 60Co, 137Cs, and 241Am were found to be 85, 1900 and 5 respectively. In most cases degree of rejection of Cs, Mo, Sr, Sb, Al, Ca, Fe, K, Mg and Na ions were more than 90% and close to 100%. The use of TeMs with a narrow pores size distribution and without tortuous channels allowed us to achieve better purification from radioactive wastes in comparison with hollow-fiber membranes. © 2019 Elsevier Ltd Ministry of Education and Science of the Republic of Kazakhstan: AP05132110 This study was funded by the Ministry of Education and Science of the Republic of Kazakhstan (grant No AP05132110 “Preparation of track-etched membranes with specified properties for membrane distillation and forward osmosis”).

The effect of irradiation of copper films with low-energy He2+ ions on their structural properties has been studied. The surface morphology and structural properties of the samples before and after irradiation have been examined by scanning electron microscopy, energy dispersive analysis, and X-ray diffraction. Bombardment of the initial samples with He2+ ions at a fluence of 1 × 1016ion/cm2 alters the surface morphology of copper films and leads to the formation of nanoscale inclusions of hexagonal shape. An increase in the fluence to 1 × 1017 ion/cm2 and higher results in the formation of cracks and amorphous oxide inclusions on the sample surface.

The paper presents the results of a study of irradiation of high-energy electrons by an array of FeNi nanostructures with doses from 50 to 500 kGy. Polycrystalline nanotubes based on FeNi, the phase composition of which is a mixture of two face-centered phases, FeNi3 and FeNi, were chosen as initial samples. During the study, the dependences of the phase transformations, as well as changes in the structural parameters as a result of electronic annealing of defects, were established. Using the method of X-ray diffraction, three stages of phase transformations were established: FeNi3 &cong, FeNi &rarr, FeNi3 ≪ FeNi &rarr, FeNi. After increasing the radiation dose above 400 kGy, no further phase changes were followed, indicating the saturation of defect annealing and completion of the lattice formation process. It was found that an increase in the degree of crystallinity and density of the microstructures as a result of irradiation indicates electronic annealing of defects and a change in the phase composition. It was established that the initial microtubes, in which two phases are present, leads to the appearance of differently oriented crystallites of different sizes in the structure, which contributes to a large number of grain boundaries and also a decrease in density, and are subject to the greatest degradation of structural properties. For modified samples, the degradation rate decreases by 5 times. In the course of the study, the prospects of the use of electron irradiation with doses above 250 kGy for directed modification of FeNi microtubes and changes in structural features were established.

The paper presents the results of studying the structural properties of Ni nanotubes affected by thermal annealing. Scanning electron microscopy, X-ray phase analysis and energy dispersive analysis were used to investigate the microstructure. An increase in the annealing temperature is found to lead to a change in the main crystallographic characteristics (unit cell parameter, crystallite size) and the appearance of new phases in the structure. The change in microarrays in the structure as a result of thermal annealing is of a two-stage nature: the first stage is characterized by an improvement in the crystal structure as a result of annealing defects; the second stage is characterized by an increase in micro-displacements in the crystal structure due to the appearance of two phases-the nickel oxide compound NiO2 and γ-Ni, whose contribution increases with the annealing temperature. At the same time, the formation of new phases in the crystal structure leads to a partial amorphization of the structure and the formation of outgrowths on tubes surface. The obtained knowledge can be applied to supplement the theory of thermal stability of nanostructures, as well as to assess their applicability in modern materials science.

Nickel nanotubes have been synthesized by electrochemical deposition, and their reactivity in aggressive media has been investigated. Kinetic curves of the variation in the atomic ratio between Ni and O in the nanotube crystal structure as a function of the medium acidity are built.

The results of targeted modification of the structure and properties of copper nanotubes by accelerated O3+ ions at a fluence of 1 × 109 to 5 × 1011 cm−2 with an energy of 1.75 MeV/nucleon are reported. XHray diffraction methods have been used to study the dynamics of changes in the crystallite shape, dislocation density, and the orientation of copper nanotubes before and after irradiation. It has been shown that irradiation with accelerated ions has a significant effect on the change in texture coefficients and dislocation density. At a fluence of 1 × 1010 cm−2 or higher, the accumulation of oxygen in the nanotube structure is observed, which leads to the appearance of oxide compounds.

This work is dedicated to developing a simple methodology that allows for the application of a thermal annealing process, which can improve the conductivity of metallic nanostructures, embedded in porous track-etched membranes based on polyethylene terephthalate (PET TeMs), but at the same time, does not compromise the mechanical properties. Zinc, copper, and cobalt nanotubes (NTs) prepared by electrochemical deposition in PET TeMs were annealed at 200 °C for different time periods. The effects of annealing treatment on the structural and electrical properties were investigated by scanning electron microscopy, X-ray diffraction, and room-temperature resistance measurements. Choosing the appropriate annealing time for Zn or Cu-NTs allows controlling the formation of an oxide phase in these nanostructures. The presence of the oxide phase in an amount of no more than 10–15 wt% led to a decrease in the resistivity and an increase in the conductivity. Thermal annealing of Co-based NTs changed intensities of the metastable fcc β-Co and stable hcp α-Co phases. The metastable β-Co phase caused additional defects due to a change in the crystallite size after 90 min of thermal annealing.

Nickel nanotubes have been formed in pores of ion-track membranes using electrochemical deposition. Morphologic and structural features of these nanostructures have been comprehensively studied. The evolution of the nanotubes wall thickness and parameters of their crystalline structure by variations of the synthesis voltage and temperature has been determined. On the base of these data the nanotubes growth mechanism has been estimated.

Copper nanotubes are electrochemically synthesized using ion-track polyethylene terephthalate templates. The structure and morphology of the nanotubes constructed under different synthesis conditions are studied with the assistance of scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction analysis, and the manometric gas-permeability method. The dependence of structural features on the electrodeposition potential is established.

Results of targeted modification of the structure and properties of ordered arrays of zinc nanotubes (Zn NTs) by accelerated Xe+22 heavy ions with a fluence of 1 × 109 to 5 × 1011 cm–2 in the energy range of 1.0–1.75 MeV/nucleon are reported. Dynamics of changes in the crystallite shape and orientation of Zn NTs before and after irradiation has been studied by X-ray diffraction. It has been shown that irradiation with accelerated ions has a significant effect on the texture coefficients of Zn NTs. In addition, at a fluence of 1 × 1011 m–2 or higher, the formation of loose areas in the structure of Zn NTs as a result of partial degradation of the crystal structure and, consequently, a decline in conductivity are observed.

The size and interposition of particles is a key parameter for the practical application of metallic nanostructures which requires the development of a synthesis method with precise control over their parameters. In this work the method for the synthesis of gold nanostructures in the pores of silicon dioxide from a gold sulfite complex and a gold chloride solution via wet chemistry technique was proposed. The influence of deposition parameters, such as deposition temperature and electrolyte composition, on the deposit morphology was studied. It was shown that gold agglomerates were unevenly distributed over the silicon surface at high temperatures and practically uniformly distributed with temperature decrease. Addition of fluoric acid at the deposition stage defines the metal precipitation selectivity into the silicon oxide pores. The peculiarities of gold nanostructures formation mechanism were discussed.

This study considers the effect of various doses of electron irradiation on the crystal structure and properties of composite catalysts based on polyethylene terephthalate track-etched membranes and copper nanotubes. Copper nanotubes were obtained by electroless template synthesis and irradiated with electrons with 3.8 MeV energy in the dose range of 100&ndash, 250 kGy in increments of 50 kGy. The original and irradiated samples of composites were investigated by X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The improved catalytic activity of composite membranes with copper nanotubes was demonstrated by the example of the reduction reaction of p-nitrophenol in the presence of sodium borohydride. Irradiation with electrons at doses of 100 and 150 kGy led to reaction rate constant increases by 35 and 59%, respectively, compared to the non-irradiated sample. This enhancing catalytic activity could be attributed to the changing of the crystallite size of copper, as well as the surface roughness of the composite membrane.

This study has been focused on the influence of the conditions of electrochemical template synthesis (i.e., potential difference and temperature of electrolyte solutions) on the structural and conductive properties of cobalt nanotubes. Polyethylene terephthalate track-etched membranes with a pore density of 1 × 109 ions/cm2 have been used as a template. Scanning electron microscopy, X-ray diffraction, and energy dispersive analysis have been used for a comprehensive elucidation of the dimensionality, chemical composition, and crystal structure of the synthesized samples. The optimum conditions for the synthesis of cobalt nanotubes with a minimum crystallographic anisotropy have been determined. It has been shown that controlling the synthesis conditions by changing electrolyte solution temperature and applied potential difference, one can vary the electrical and conductive properties of cobalt nanotube arrays, which have promising application in magnetic recording storage devices, high-precision magnetic field sensors, and optical devices.

Cobalt nanotubes were fabricated by template synthesis in the pores of track membranes based on polyethylene terephthalate; modified by electron irradiation; and studied by scanning electronic microscopy, energy-dispersive analysis, and X-ray diffraction analysis. It was found that the resistivity of Co nanotubes dropped by 16.7 and 21.6% after electron irradiation with a dose of 50 and 100 kGy, respectively. It was demonstrated that the change in conductive properties is associated with the rearrangement of crystal structure after electron irradiation owing to the suppression of influence of the metastable β-Co phase and an increase in the degree of texturing in the direction.

Results of studies of the effect of thermal annealing on the structural and conducting properties of ordered arrays of zinc nanotubes prepared by electrochemical deposition in track-etched membranes based on polyethylene terephthalate (PET) have been described. The dimensions, chemical composition, and crystal structure of the synthesized samples have been integrally analyzed using scanning electron microscopy, X-ray diffraction, and energy dispersive analysis. It has been shown that the thermal annealing of zinc-based nanotubes makes it possible to control the formation of an oxide phase in the nanostructures. The presence of the ZnO oxide phase in an amount of no more than 10 wt % leads to a decrease in the resistivity and an increase in the conductivity. In addition, by changing the crystal structure of Zn nanotubes by thermal annealing, it is possible to prepare ordered arrays of n-type semiconductors with considerable prospects of widespread use in nanoelectronics and nanooptics.

The main goal of this work is to study the effect of irradiation with protons with an energy of 0.5–1.5 MeV at a fluence of 1х1017 proton/cm2 on the mechanical and structural properties of AlN ceramics. The choice of AlN ceramics as objects of study is due to their high resistance to radiation damage, their great potential for using them as structural materials, dosimetric materials, etc. During the tests, it was found that at low incident particle energies the degree of deformation of the crystal structure is greatest, due to the fact that all radiation defects are closed in a small volume of the surface layer. An increase in proton energy leads to an increase in the path length of protons in ceramics, while a decrease in damage to the surface layer is observed, however, the damage depth becomes larger with an increase in proton energy. The obtained results confirm a high degree of resistance to hydrogenation processes when irradiated with protons with energies of 1.0–1.5 MeV, however, at energies of incident protons of 0.5 MeV, a decrease in strength properties is observed due to the presence of a large number of dislocation and point defects in the near-surface layer of small volume, which leads to partial disordering and degradation of structural and optical properties.

The paper presents data on the radiation resistance of Ni nanotubes when irradiated with heavy Xe22+ ions with an energy of 230 MeV and fluences of 5 × 1010–5 × 1012 ion/cm2. The choice of fluences of 5 × 1010–5 × 1012 ion/cm2 is due to the possibility of simulating the effects of single ion collisions at low irradiation fluences, for which the probability of two ions entering one point is quite low, and by modeling the effects of overlapping defects from two or more ions at high radiation densities. The initial nanostructures are polycrystalline nanotubes with a face-centered nickel phase. According to the results of X-ray phase analysis, no oxide impurities or oxide phases are observed in the structure of nanotubes, which indicates the absence of oxidative processes in the synthesized nanostructures. Also, for the irradiated samples, there are no new diffraction peaks, which indicates the absence of phase transition processes as a result of irradiation. It was found that, at low irradiation fluences, a change in the orientation of crystallites occurs, which indicates a rearrangement of the crystal structure and partial ordering. However, an increase in the irradiation fluence above 1 × 1011 ion/cm2 leads to a sharp decrease in long-range intensities, as well as a shift of diffraction maxima to the region of small angles, which indicates a distortion of the crystal structure and its partial disordering as a result of irradiation. In the case of large irradiation fluences, which are characterized by the occurrence of areas of overlapping ion trajectories, the material exhibits disorientation of crystallites in the structure, as well as the absence of pronounced texture orientations.

The most important limitation for boron neutron capture therapy of cancer is the selective accumulation of boron compounds in tumor tissues in significant quantities. In this paper, we describe the possibility to use magnetic Ni/Fe nanotubes as carriers for boron delivery. Carborane derivatives containing 10 and 21 boron atoms per molecule were immobilized on Ni/Fe nanotubes by covalent and ionic interactions. Magnetic properties of NTs were investigated by Mossbauer spectroscopy. Structure, element, chemical composition, and morphology of obtained magnetic nanotubes were studied by XRD, SEM-EDA, and FTIR spectroscopy. Results indicate success immobilization of carborane derivatives on Ni/Fe nanotubes and great potential to use them as carriers for boron neutron cancer therapy of cancer.

Gold nanostructures were fabricated in porous SiO2/Si ion-track templates by the wet chemical deposition from a solution of Au(I) sulfite complex. Their morphological features were analyzed, and features of the deposition processes were determined. A mechanism describing the selective formation of gold nanostructures in the pores of SiO2 was proposed. The present approach allows us to control shape and size of Au nanostructures those which can be used as plasmonic active surfaces for SERS detecting of small amounts of biological and chemical substances.

Simple method of tunable synthesis of copper nanotubes based on template synthesis was developed. A comprehensive study of the structural, morphological and electrical characteristics of the obtained nanostructures was carried out. Characterization of structural features was made by methods of scanning electron microscopy, energy dispersive spectroscopy and X-ray diffractometry analysis. Evaluation of wall thickness is made by methods of gas permeability. Electrical conductivity of nanotubes was define in the study of their current-voltage characteristics. The possibility to control of copper nanotubes physical properties by variation of the deposition parameters was shown.

Iron-nickel nanotubes consisting of 20% Ni and 80% Fe with an aspect ratio of about 100 were synthesized by electrochemical deposition in the pores of polyethylene terephthalate ion-track membranes. The main morphological parameters such as composition, wall thickness and structural characteristics were defined. Macro- and micromagnetic parameters of FeNi nanotubes were determined. © 2017, Electromagnetics Academy. All rights reserved.