Publications by authors named "Voronov V"

The peculiarities of the crystal formation from supersaturated aqueous solutions of CuSO on polymer substrates were studied using X-ray diffractometry. During the crystal formation, the test solutions were irradiated with one or two counter-propagating ultrasonic beams. Test solutions were prepared using natural deionized water with a deuterium content of 157 ± 1 ppm.

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Introduction: The process of forming selenium nanoparticles with various shapes and structures through laser ablation and fragmentation in various solvents has been explored.

Methods: Laser ablation and laser fragmentation techniques were employed using nanosecond Nd:YAG second harmonic laser irradiation in 9 different working fluids, including water. The characteristics of the resulting nanoparticles were assessed using transmission electron microscopy (TEM), dynamic light scattering (DLS), spectroscopy, and X-ray diffraction (XRD) methods.

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Recently, progress has been made in fabricating diamond-based scintillators with integrated rare-earth luminescent particles. These luminescent particles are integrated into the bulk of diamond during their synthesis by chemical vapor deposition (CVD). However, the growth conditions include a chemically aggressive plasma environment and elevated temperatures, which results in the partial degradation of particles and a decrease in the intensity of their luminescence.

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The process of laser-induced breakdown of amorphous and crystalline selenium nanoparticles (Se NPs) of various shapes during nanosecond laser fragmentation of aqueous colloidal solutions of nanoparticles with different concentrations has been studied. The methods of studying the characteristics of plasma and acoustic oscillations induced by optical breakdown are applied. The methods of assessing the concentration of hydrogen peroxide and hydroxyl radicals, the amount of long-lived reactive species of protein and 8-oxoguanine are applied.

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The peculiarities of crystal growth on a Nafion polymeric substrate from supersaturated aqueous solutions of initial substances were studied. The solutions were prepared based on deionized natural water and deuterium-depleted water. As was found earlier, in natural water (deuterium content 157 ± 1 ppm) polymer fibers are capable of unwinding towards the bulk of the liquid, while in deuterium-depleted water (deuterium content ≤ 3 ppm) there is no such effect.

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With the help of laser ablation, a technology for obtaining nanosized crystalline selenium particles (SeNPs) has been created. The SeNPs do not exhibit significant toxic properties, in contrast to molecular selenium compounds. The administration of SeNPs can significantly increase the viabilities of SH-SY5Y and PCMF cells after radiation exposure.

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A detailed study of charge transport in the paramagnetic phase of the cage-cluster dodecaboride Ho0.8Lu0.2B12 with an instability both of the fcc lattice (cooperative Jahn−Teller effect) and the electronic structure (dynamic charge stripes) was carried out at temperatures 1.

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The influence of the number of oxidized terbium nanoparticles on the intensity of physicochemical processes occurring during optical breakdown in aqueous colloidal solutions of nanoparticles has been studied. It is shown that the effect of the number of oxidized terbium nanoparticles on the physicochemical processes occurring during optical breakdown depends significantly on the fluence of laser radiation. At a fluence of less than 100-110 J/cm, plasma formation processes occur more intensively on less-oxidized (metal) nanoparticles.

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Objective: To study satisfaction with treatment as a predictor of compliance in patients with mental disorders prone to committing socially dangerous acts (SDA).

Material And Methods: The study included 83 patients of a psycho-neurological institution prone to commit SDA. The comparison group consisted of 88 mental patients who were not inclined to commit SDA.

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The high-resolution H and C NMR spectra (CHCl solution) of sterically non-rigid heterospin complexes CoL, CoL-dipy, and CoL-phen (where L is 4-(3',3',3'-trifluoro-2'-oxopropylidene)-2,2,5,5-tetramethyl-3-imidazolidine-1-oxyl) have been studied. The specific of the NMR phenomenon in paramagnetic systems is briefly analyzed. It is shown that the NMR spectra modified by hyperfine coupling can be successfully employed for investigation of the complexation processes.

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The major challenge in optical ceramic technology is the quality of the starting precursor powder for pressing, which is a key element in the optical ceramic industry. One express and helpful technique for the estimation of powder quality is the estimation of the quantum yield of up-conversion luminescence; therefore precursor powders must exhibit high values of up-conversion luminescence efficiency. Single-phase solid solutions based on strontium fluoride doped with ytterbium and erbium were synthesised by co-precipitation from aqueous solutions using sodium fluoride, potassium fluoride and ammonium fluoride as fluorinating agents.

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Precise angle-resolved magnetoresistance (ARMR) and magnetization measurements have revealed (i) strong charge transport and magnetic anisotropy and (ii) emergence of a huge number of magnetic phases in the ground state of isotopicallyB-enriched single crystals of TmBantiferromagnetic (AF) metal with fcc crystal structure and dynamic charge stripes. We analyze for the first time the angular-phase diagrams of AF state of TmBreconstructed from experimental ARMR and magnetization data arguing that the symmetry lowering leads to the appearance of several radial phase boundaries between different phases in the AF state. It is proposed that the suppression of the indirect Ruderman-Kittel-Kasuya-Yosida (RKKY) exchange along ⟨110⟩ directions between nearest neighboring magnetic moments of Tmions and subsequent redistribution of conduction electrons to quantum fluctuations of the electron density (dynamic stripes) are the main factors responsible for the anisotropy.

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The goal of this paper is to review the pharmacological profile of betahistine and evidence for using it in the treatment of common vestibular disorders. Betahistine is a weak agonist for histamine H1 receptors and strong antagonist for histamine H3 receptors. It demonstrates the maximum benefit in different types of peripheral vertigo, especially in Meniere's disease.

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Hydrophobic up-conversion nanocomposite films have been developed based on TEMPO-oxidized cellulose nanofibrils (TOCNF) modified with alkyl ketene dimer (AKD) as a matrix and MF:Ho (M = Ca, Sr) as a phosphor. Fabrication of homogeneous, strong and translucent TOCNF/MF:Ho-AKD films with water contact angle of 123 ± 2° was accomplished with mild drying at 110 °C. These hydrophobic nanocomposite films demonstrated stable up-conversion luminescence in the visible spectral range upon excitation of the I level of Ho ions by laser irradiation at 1912 nm both under ambient conditions and in a humid atmosphere (92 ± 2% humidity).

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Experimental results are presented on laser-assisted synthesis of composite nanoparticles of perovskite BaTiO with gold nanoparticles using the technique of laser ablation in water and aqueous solution of hydrogen peroxide. Nanoparticles of BaTiO are generated by near IR laser radiation with pulse durations of 170 fs, 1 ps, and 200 ns. Nanoparticles of barium titanate BaTiO (BTO) have tetragonal structure for all used pulse durations.

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Seebeck effect in the crystalline samples of EuYbB(= 0, 0.082, 0.127, 0.

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Measurements of the refractive indices and the full set of longitudinal acousto-optical figures of merit in an orthorhombic single-crystal indium iodide (InI) were carried out. The high acousto-optic characteristics ( up to 1100×10) and strong optical anisotropy (=0.47) make it possible to design various types of high-performance acousto-optic devices of the middle and far-infrared spectral range.

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Aim: To study behavioral factors as a predictor of the adherence to psychopharmacotherapy in patients inclined to socially dangerous actions.

Material And Methods: The total number of people with mental disorders that pose a danger to society in the city of Cherepovets was 148 at the moment of the study. Eighty-three patients were examined.

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Upconversion nanoparticles have attracted considerable attention as luminescent markers for bioimaging and sensing due to their capability to convert near-infrared (NIR) excitation into visible or NIR luminescence. However, the wavelength of about 970 nm is commonly used for the upconversion luminescence excitation, where the strong absorption of water is observed, which can lead to laser-induced overheating effects. One of the strategies for avoiding such laser-induced heating involves shifting the excitation into shorter wavelengths region.

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Simple cubic 'open' perovskite ScF stands out among trifluoride materials in its large, isotropic negative thermal expansion (NTE), but also its proximity of its zero-temperature state to a structural phase transition. Here we report a temperature- and frequency-dependent lattice dynamical study of Brillouin zone center lattice excitations of single crystals of ScF using infrared reflectivity measurements. In addition to quantifying the mode strengths and energies in single crystals of this interesting material, we also find strong evidence for multiphonon absorption processes which excite the zone-edge incipient soft modes associated with NTE and the structural quantum phase transition.

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This Article covers the influence of the concentration of gold nanoparticles on laser-induced water decomposition. It was established that addition of gold nanoparticles intensifies laser-induced water decomposition by almost 2 orders of magnitude. The water decomposition rate was shown to be maximal at a nanoparticle concentration around 10 NP/mL, whereas a decrease or increase of nanoparticle concentration leads to a decrease of water decomposition rate.

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Crystal structure of LaF single crystal is refined in tysonite-type trigonal unit cell P [Formula: see text] c1 using density functional theory calculations and Raman spectroscopy. It is shown that trigonal structure with P [Formula: see text] c1 space group is more energy-efficient than hexagonal structure with space group P6 cm. Simulated Raman spectra obtained using LDA approximation is in much better agreement with experimental data than that obtained with PBE and PBEsol functionals of GGA.

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Spatial anisotropy generated spontaneously in the translationally invariant metallic phase, i.e. electron nematic effect, addresses a great challenge for both experimentalists and theoreticians.

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The peculiarities of nuclear spin relaxation in the paramagnetic systems have been analyzed taking into account the exchange processes. The analysis is based on the modified Solomon-Bloembergen equations. In this line, the conditions of detecting of the NMR signals of samples are discussed depending on resonance frequency of the NMR spectrometer and characteristic relaxation time.

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Complex electroencephalographic (EEG), stabilographic and psychological study was executed during the number dual tasks performance--postural control and calculation in 25 healthy volunteers (age 25 ± 0.7). Successful performances of dual tasks required a high usage of cognitive resources, such as memory and attention as well as good motor command and low level of anxiety.

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