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In this work, we synthesized two new benzo-18-azacrown-6 ethers bearing picolinate and pyridine pendant arms and studied the copper complexes of these ligands, as well as those of an acetate analog.

Formation of Yb and Tm radioisotopes upon irradiation of ytterbium of natural isotopic composition by bremsstrahlung photons with energies up to 55 MeV was studied. The yield of the medical radionuclide 167Tm was (7.8 ± 1.1) × 103 Bq × μA-1 × h−1 × cm2 × g−1. Thulium radioisotopes were separated from irradiated ytterbium target by extraction chromatography on the LN Resin sorbent in nitric media. Efficient separation of tracer amounts of thulium from tens of milligrams of ytterbium could be achieved. The method can be of practical importance for the production of 167Tm when using a 168Yb enriched target.

Formation of Sc radioisotopes under the irradiation of titanium of natural isotopic composition by bremsstrahlung photons with energies up to 55 MeV was studied. The yield of 47Sc is 5·105 Bq/μA h (g/cm2). Inevitable impurities are 46Sc and 48Sc (1.5% and 9.1% of 47Sc radioactivity at EOB, respectively). 47Sc was separated by extraction chromatography on a DGA resin in HNO3 and HCl media. The separation procedure takes about 2 h, the radiochemical efficiency was > 97%. The result was compared with other photonuclear experiments on titanium nuclei. It is shown that the photonuclear method can be used for the production of therapeutic amounts of 47Sc.

A new method for separation of 97Ru radionuclide from irradiated by a-particles molybdenum, which potentially could be applied in nuclear medicine, is proposed. Carrier-free ruthenium-97 was separated from macroamounts of molybdenum and trace amounts of technetium by extraction chromatography on a commercial DGA sorbent. The distribution of 97Ru in the body organs of mice was studied.

Production of medical radionuclide 67Cu by the irradiation of Zn of natural isotopic composition by bremsstrahlung photons of maximum energy of 55 MeV was studied. Production yields of 67Cu and other activation products were determined. The yield of 67Cu is (2.34 ± 0.07) × 105 Bq/(μA h g/cm2) at EOB. The experimental data were compared with the results of other experiments and theoretical calculations based on the statistical model in the TALYS software and on the combined model of photonuclear reactions. Technique of chemical separation of 67Cu from irradiated zinc target based on extraction chromatography using CU Resin was applied. Radiochemical yield was > 95%, separation time was 1 h. The possibility of production of medical quantities was discussed.

Copper-based radiopharmaceuticals are of high interest these days owing to the decay properties of copper radioisotopes. In contrast, labeled zinc compounds have been less studied for applications in nuclear medicine. In this study, the stability of labeled zinc and copper complexes with two azacrown ether ligands was investigated and compared. Then, the in vitro and in vivo stability of the studied zinc complexes was demonstrated, with the complexes showing promise for biomedical applications. In contrast, analogous copper complexes quickly dissociated in the presence of serum proteins. Furthermore, a simple method for the production of radiochemically pure 65Zn was proposed, and the opportunity for its use as a surrogate radionuclide for research into potential zinc-containing radiopharmaceuticals was demonstrated.

In this work, the separation of 89Zr, a radionuclide promising for positron-emission tomography, from an irradiated yttrium target using different extraction-chromatographic resins (TEVA, UTEVA, TRU, and LN resins ©Triskem) was studied. Distribution coefficients of Zr(IV) onto TEVA, LN (in HCl solutions), and onto TRU (in HCl and HNO3) were determined. The optimum conditions for the separation of Zr(IV) and Y(III) using these resins were proposed. In each case, the maximum separation factor was higher than 105. The developed separation procedures allow to obtain 89Zr of high radiochemical purity for dilute mineral acids.

A method for obtaining 156, 155, 154m2, 154, 153Tb radiotracers by the irradiation of a europium oxide target of natural isotopic composition by 27 MeV α-particles is proposed. Terbium can be efficiently separated from bulk of europium by the reduction of the latter by zinc in an acidic solution and precipitation as EuSO4. The optimum Zn/Eu3+ and (NH4)2SO4/Eu3+ molar ratios are 20 and 3, respectively. Terbium is additionally purified from europium and gadolinium by extraction chromatography using LN Resin. It is demonstrated that optimum separation is attained in 0.6 M HNO3. The Tb/Eu separation coefficient was ~5·105. The yield of terbium was about 90%. Time of all steps was 1.5–2 h. The proposed procedure makes it possible to obtain no carrier added terbium radiotracers.

Filtration efficiency of Ni(II) from aqueous solution using pristine and modified MWCNTs filters was investigated as a function of Ni(II) ion concentration, pH, and filter mass. MWCNTs were synthesized by CVD method and modified using two complementary treatments, purification (using a mixture of hydrochloric acid and hydrogen peroxide) and functionalization (using nitric acid). The effect and mechanism of each treatment on the structural integrity of pristine MWCNTs has been studied. Morphology of the pristine and modified filters was investigated by Raman Spectrometry (RS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared (FTIR) spectrometry and Thermogravimetric analysis. It was found from Raman spectra that the ratio of the intensity of D-band to that of G-band decreased by purification process, and increased by functionalization process. The adsorption mechanism of Ni(II) onto the surface functional groups of modified MWCNTs was confirmed by FTIR spectrum. The filtration results showed that the removal efficiency of Ni(II) is strongly dependent on pH and could reach 85% at pH = 8. Also, modified MWCNT filters can be reused through many cycles of regeneration with high performance. Functionalized MWCNTs filters may be a promising adsorbent candidate for heavy metal removal from wastewater.

Carbon nanotubes (CNTs) have become the focus of attention of many scientists and companies worldwide. CNT-based filters have a prospective advantage in comparison to the commercial filters already in operation because they are light weight and do not require electricity to operate. This investigation handles the filtration efficiency of manganese and iron from aqueous solution using commercial multiwalled carbon nanotubes (MWCNTs) (Taunit). The effects of different parameters such as CNT filter mass, concentration of manganese and iron in aqueous solution and pH of aqueous solution on removal of these heavy metals are determined. From these investigations, the removal efficiency of manganese and iron could reach 71.5% and 52% respectively for concentration 50 ppm, suggesting that Taunit is an excellent adsorbent for manganese and iron removal from water. There was a significant increase in removal efficiency at pH = 3 for manganese and pH = 8 for iron. The effect of oxidation on the structural of MWCNTs was characterized by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) techniques to investigate the functionalization with oxygen-containing and outer diameter distribution. It was found that functionalized CNT-based filters are more efficient at removing manganese and iron from aqueous solutions. Oxidized MWCNTs may be a promising candidate for heavy metal ion removal from industrial wastewater.

The yields of 66Ga, 67Ga, 68Ga, 70Ga, 65Zn, and 69mZn upon irradiation of gallium with the natural isotopic composition by the bremsstrahlung photon beam with the energy up to 55 MeV were measured. The yield of 69mZn yield was 0.13 MBq μA–1h–1g–1. A simple and rapid method for 69mZn separation based on the extraction of gallium followed by ion-exchange chromatography was proposed.

The generation of leading centers in the Belousov-Zhabotinsky reaction by a 30-MeV collimated electron beam has been investigated. The center generation threshold is estimated to be 2.0 ± 0.5 kGy.

The generation of leading centers in the Belousov-Zhabotinsky reaction under the action of collimated radiation with a high linear energy transfer has been investigated. To get insight into the mechanism of the effect of radiation on the Belousov-Zhabotinsky reaction, the radicalator model was modified to involve the interaction of the reactants with the •OH radical produced by water radiolysis.

The generation of leading centers was observed in an oscillatory reaction of the Belousov‐Zhabotinsky type under the action of collimated radiation with high linear energy transfer. Threshold values of the absorbed dose for the generation and complete quenching of autowaves were estimated. For modeling the effect of hard ionizing radiation on the Belousov‐Zhabotinsky reaction, we proposed a modified radicalator model taking into account the interaction of reactants with ⋅OH radical, which is produced in the course of irradiation as a result of the radiolysis of water.