Publications by authors named "Alex V Trukhanov"

12 Publications

  • Page 1 of 1

Experimental and Theoretical Study of Radiation Shielding Features of CaO-KO-NaO-PO Glass Systems.

Materials (Basel) 2021 Jul 6;14(14). Epub 2021 Jul 6.

Physics Department, Faculty of Science, Alexandria University, Alexandria 21511, Egypt.

The gamma radiation shielding ability for CaO-KO-NaO-PO glasses were experimentally determined between 0.0595 and 1.41 MeV. The experimental MAC results were compared with theoretical results obtained from the XCOM software to test the accuracy of the experimental values. Additionally, the effect of increasing the PO in the glass composition, or reducing the NaO content, was evaluated at varying energies. For the fabricated glasses, the experimental data strongly agreed with the XCOM results. The effective atomic number (Z) of the fabricated glasses was also determined. The Z values start out at their maximum (12.41-12.55) at the lowest tested energy, 0.0595 MeV, and decrease to 10.69-10.80 at 0.245 MeV. As energy further increases, the Z values remain almost constant between 0.344 and 1.41 MeV. The mean free path (MFP) of the fabricated glasses is investigated and we found that the lowest MFP value occurs at the lowest tested energy, 0.0595 MeV, and lies within the range of 1.382-1.486 cm, while the greatest MFP can be found at the highest tested energy, 1.41 MeV, within the range of 8.121-8.656 cm. At all energies, the KCNP40 sample has the lowest MFP, while the KCNP60 sample has the greatest. The half value layer (HVL) for the KCNP-X glasses is determined. For all the selected energies, the HVL values follow the order of KCNP40 < KCNP45 < KCNP50 < KCNP55 < KCNP60. The HVL of the KCNP50 sample increased from 0.996 to 2.663, 3.392, 4.351, and 5.169 cm for energies of 0.0595, 0.245, 0.444, 0.779, and 1.11 MeV, respectively. The radiation protection efficiency (RPE) results reveal that decreasing the PO content in the glasses improves the radiation shielding ability of the samples. Thus, the KCNP40 sample has the best potential for photon attenuation applications.
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http://dx.doi.org/10.3390/ma14143772DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8307780PMC
July 2021

Graphene Oxide Nanoparticles Modified Paper Electrode as a Biosensing Platform for Detection of the Gene of .

Sensors (Basel) 2021 Jun 25;21(13). Epub 2021 Jun 25.

Department of Technology of Electronics Materials, National University of Science and Technology "MISiS", Leninsky Av., 4, 119049 Moscow, Russia.

The unique structural and electrochemical properties of graphene oxide (GO) make it an ideal material for the fabrication of biosensing devices. Therefore, in the present study, graphene oxide nanoparticles modified paper electrodes were used as a low-cost matrix for the development of an amperometric DNA sensor. The graphene oxide was synthesized using the modified hummers method and drop cast on a screen-printed paper electrode (SPPE) to enhance its electrochemical properties. Further, the GO/SPPE electrode was modified with a 5'NH2 labeled ssDNA probe specific to the gene of using carbodiimide cross-linking chemistry. The synthesized GO was characterized using UV-Vis, FTIR, and XRD. The layer-by-layer modification of the paper electrode was monitored via FE-SEM, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The sensor response after hybridization with single-stranded genomic DNA (ssGDNA) of was recorded using differential pulse voltammetry (DPV). Methylene blue (1 mM in PBS buffer, pH 7.2) was used as a hybridization indicator and [Fe(CN)] (2.5 mM in PBS buffer, pH 7.2) as a redox probe during electrochemical measurements. The developed DNA sensor shows excellent sensitivity (1228.4 µA/cm/ng) and LOD (20 pg/µL) for detection of GDNA using differential pulse voltammetry (DPV).
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http://dx.doi.org/10.3390/s21134366DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8271629PMC
June 2021

Polysubstituted High-Entropy [LaNd](CrMnFeCoNi)O Perovskites: Correlation of the Electrical and Magnetic Properties.

Nanomaterials (Basel) 2021 Apr 15;11(4). Epub 2021 Apr 15.

Laboratory of Single Crystal Growth, South Ural State University, 454080 Chelyabinsk, Russia.

La-, Nd- and La/Nd-based polysubstituted high-entropy oxides (HEOs) were produced by solid-state reactions. Composition of the B-site was fixed for all samples (CrMnFeCoNi) with varying of A-site cation (La, Nd and LaNd). Nominal chemical composition of the HEOs correlates well with initial calculated stoichiometry. All produced samples are single phase with perovskite-like structure. Average particle size is critically dependent on chemical composition. Minimal average particle size (~400 nm) was observed for the La-based sample and maximal average particle size (5.8 μm) was observed for the Nd-based sample. The values of the configurational entropy of mixing for each sample were calculated. Electrical properties were investigated in the wide range of temperatures (150-450 K) and frequencies (10-10 Hz). Results are discussed in terms of the variable range hopping and the small polaron hopping mechanisms. Magnetic properties were analyzed from the temperature and field dependences of the specific magnetization. The frustrated state of the spin subsystem was observed, and it can be a result of the increasing entropy state. From the Zero-Field-Cooling and Field-Cooling regimes (ZFC-FC) curves, we determine the average and S maximum size of a ferromagnetic nanocluster in a paramagnetic matrix. The average size of a ferromagnetic cluster is ~100 nm (La-CMFCNO) and ~60 nm (LN-CMFCNO). The S maximum size is ~210 nm (La-CMFCNO) and ~205 nm (LN-CMFCNO). For Nd-CMFCNO, spin glass state (ferromagnetic cluster lower than 30 nm) was observed due to f-d exchange at low temperatures.
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http://dx.doi.org/10.3390/nano11041014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8071509PMC
April 2021

Impact of Tm and Tb Rare Earth Cations Substitution on the Structure and Magnetic Parameters of Co-Ni Nanospinel Ferrite.

Nanomaterials (Basel) 2020 Nov 29;10(12). Epub 2020 Nov 29.

Laboratory of Magnetic Films Physics, SSPA "Scientific and Practical Materials Research Centre of NAS of Belarus", 220072 Minsk, Belarus.

Tm-Tb co-substituted Co-Ni nanospinel ferrites (NSFs) as (CoNi) [TmTbFe]O (x = 0.00-0.05) NSFs were attained via the ultrasound irradiation technique. The phase identification and morphologies of the NSFs were explored using X-rays diffraction (XRD), selected area electron diffraction (SAED), and transmission and scanning electronic microscopes (TEM and SEM). The magnetization measurements against the applied magnetic field (M-H) were made at 300 and 10 K with a vibrating sample magnetometer (VSM). The various prepared nanoparticles revealed a ferrimagnetic character at both 300 and 10 K. The saturation magnetization (M), the remanence (M), and magneton number (nB) were found to decrease upon the Tb-Tm substitution effect. On the other hand, the coercivity (H) was found to diminish with increasing x up to 0.03 and then begins to increase with further rising Tb-Tm content. The H values are in the range of 346.7-441.7 Oe at 300 K to 4044.4-5378.7 Oe at 10 K. The variations in magnetic parameters were described based on redistribution of cations, crystallites and/or grains size, canting effects, surface spins effects, super-exchange interaction strength, etc. The observed magnetic results indicated that the synthesized (CoNi)[TmTbFe]O NSFs could be considered as promising candidates to be used for room temperature magnetic applications and magnetic recording media.
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http://dx.doi.org/10.3390/nano10122384DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760020PMC
November 2020

Functional SrBaSmFeO/(NiZnFeO) Hard-Soft Ferrite Nanocomposites: Structure, Magnetic and Microwave Properties.

Nanomaterials (Basel) 2020 Oct 27;10(11). Epub 2020 Oct 27.

Department of Nanomedicine Research, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia.

This paper reports the correlation between the composition of the functional SrBaSmFeO/(NiZnFeO) hard-soft nanocomposites (SrBaSmFe/(NiZnFe) NCs), where 0.0 ≤ x ≤ 3.0, and their structural features, magnetic, and microwave properties. SrBaSmFe/(NiZnFe) hard/soft ferrite NCs are produced using the citrate combustion method. According to the XRD analysis, all samples showed the co-existence of both SrBaSmFe and NiZnFe phases in different ratios. Magnetic properties are measured in a wide range of magnetic fields and temperatures (10 and 300 K) and correlated well with the composition of the investigated samples. The microwave properties (frequency dispersions of the magnetic permeability, and electrical permittivity) are discussed by using the co-axial method in the frequency range of 0.7-18 GHz. Non-linear dependences of the main microwave features were observed with varying of composition. The microwave behavior correlated well with the composite theory. These results could be used in practice for developing antenna materials.
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http://dx.doi.org/10.3390/nano10112134DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7692059PMC
October 2020

Morphology and Microstructure Evolution of Gold Nanostructures in the Limited Volume Porous Matrices.

Sensors (Basel) 2020 Aug 6;20(16). Epub 2020 Aug 6.

Departament of Functional Interfaces, Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, 07745 Jena, Germany.

The modern development of nanotechnology requires the discovery of simple approaches that ensure the controlled formation of functional nanostructures with a predetermined morphology. One of the simplest approaches is the self-assembly of nanostructures. The widespread implementation of self-assembly is limited by the complexity of controlled processes in a large volume where, due to the temperature, ion concentration, and other thermodynamics factors, local changes in diffusion-limited processes may occur, leading to unexpected nanostructure growth. The easiest ways to control the diffusion-limited processes are spatial limitation and localized growth of nanostructures in a porous matrix. In this paper, we propose to apply the method of controlled self-assembly of gold nanostructures in a limited pore volume of a silicon oxide matrix with submicron pore sizes. A detailed study of achieved gold nanostructures' morphology, microstructure, and surface composition at different formation stages is carried out to understand the peculiarities of realized nanostructures. Based on the obtained results, a mechanism for the growth of gold nanostructures in a limited volume, which can be used for the controlled formation of nanostructures with a predetermined geometry and composition, has been proposed. The results observed in the present study can be useful for the design of plasmonic-active surfaces for surface-enhanced Raman spectroscopy-based detection of ultra-low concentration of different chemical or biological analytes, where the size of the localized gold nanostructures is comparable with the spot area of the focused laser beam.
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http://dx.doi.org/10.3390/s20164397DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7472280PMC
August 2020

Peculiarities of the Crystal Structure Evolution of BiFeO-BaTiO Ceramics across Structural Phase Transitions.

Nanomaterials (Basel) 2020 Apr 21;10(4). Epub 2020 Apr 21.

School of Natural Sciences and Mathematics, Ural Federal University, 620026 Ekaterinburg, Russia.

Evolution of the crystal structure of ceramics BiFeO-BaTiO across the morphotropic phase boundary was analyzed using the results of macroscopic measuring techniques such as X-ray diffraction, differential scanning calorimetry, and differential thermal analysis, as well as the data obtained by local scale methods of scanning probe microscopy. The obtained results allowed to specify the concentration and temperature regions of the single phase and phase coexistent regions as well as to clarify a modification of the structural parameters across the rhombohedral-cubic phase boundary. The structural data show unexpected strengthening of structural distortion specific for the rhombohedral phase, which occurs upon dopant concentration and temperature-driven phase transitions to the cubic phase. The obtained results point to the non-monotonous character of the phase evolution, which is specific for metastable phases. The compounds with metastable structural state are characterized by enhanced sensitivity to external stimuli, which significantly expands the perspectives of their particular use.
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http://dx.doi.org/10.3390/nano10040801DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7221926PMC
April 2020

Investigation of AC-Measurements of Epoxy/Ferrite Composites.

Nanomaterials (Basel) 2020 Mar 9;10(3). Epub 2020 Mar 9.

School of Electronics and Electrical Engineering, Lovely Professional University, Phagwara, Punjab 144411, India.

A pure ferrite and epoxy samples as well as the epoxy/ferrite composites with different 20 wt.%, 30 wt.%, 40 wt.%, and 50 wt.% weight ferrite contents have been prepared by the chemical co-precipitation method. AC-conductivity and dielectric properties such as the dielectric constant and dielectric loss of the prepared samples have been studied. The obtained results showed that the samples had a semiconductor behavior. The dielectric constant of the composites has been calculated theoretically using several models. For the composite sample that contains 20 wt.% of ferrites, these models give satisfactory compliance, while for the composite samples with a higher percentage of nanofillers, more than 30 wt.% theoretical results do not coincide with experimental data. The investigated polymer has very low conductivity, so this type of polymer can be useful for high-frequency applications, which can reduce the losses caused by eddy current. Thus, the prepared samples are promising materials for practical use as elements of microwave devices.
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http://dx.doi.org/10.3390/nano10030492DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7153626PMC
March 2020

Functional Magnetic Composites Based on Hexaferrites: Correlation of the Composition, Magnetic and High-Frequency Properties.

Nanomaterials (Basel) 2019 Dec 2;9(12). Epub 2019 Dec 2.

Department of Technology of Electronics Materials, National University of Science and Technology "MISiS", Leninskii av., Moscow 4119049, Russia.

The paper describes preparation features of functional composites based on ferrites, such as "Ba(FeGa)O/epoxy," and the results of studying their systems; namely, the correlation between structure, magnetic properties and electromagnetic absorption characteristics. We demonstrated the strong mutual influence of the chemical compositions of magnetic fillers (Ba(FeGa)O 0.01 < < 0.1 solid solutions), and the main magnetic (coercivity, magnetization, anisotropy field and the first anisotropy constant) and microwave (resonant frequency and amplitude) characteristics of functional composites with 30 wt.% of hexaferrite. The paper presents a correlation between the chemical compositions of composites and amplitude-frequency characteristics. Increase of Ga-content from = 0 to 0.1 in Ba(FeGa)O/epoxy composites leads to increase of the resonant frequency from 51 to 54 GHz and absorption amplitude from -1.5 to -10.5 dB/mm. The ability to control the electromagnetic properties in these types of composites opens great prospects for their practical applications due to high absorption efficiency, and lower cost in comparison with pure ceramics oxides.
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http://dx.doi.org/10.3390/nano9121720DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955991PMC
December 2019

Fe₃O₄ Nanoparticles for Complex Targeted Delivery and Boron Neutron Capture Therapy.

Nanomaterials (Basel) 2019 Mar 31;9(4). Epub 2019 Mar 31.

School of Engineering, Nazarbayev University, 010000 Nur-Sultan, Kazakhstan.

Magnetic Fe₃O₄ nanoparticles (NPs) and their surface modification with therapeutic substances are of great interest, especially drug delivery for cancer therapy, including boron-neutron capture therapy (BNCT). In this paper, we present the results of boron-rich compound (carborane borate) attachment to previously aminated by (3-aminopropyl)-trimethoxysilane (APTMS) iron oxide NPs. Fourier transform infrared spectroscopy with Attenuated total reflectance accessory (ATR-FTIR) and energy-dispersive X-ray analysis confirmed the change of the element content of NPs after modification and formation of new bonds between Fe₃O₄ NPs and the attached molecules. Transmission (TEM) and scanning electron microscopy (SEM) showed Fe₃O₄ NPs' average size of 18.9 nm. Phase parameters were studied by powder X-ray diffraction (XRD), and the magnetic behavior of Fe₃O₄ NPs was elucidated by Mössbauer spectroscopy. The colloidal and chemical stability of NPs was studied using simulated body fluid (phosphate buffer-PBS). Modified NPs have shown excellent stability in PBS (pH = 7.4), characterized by XRD, Mössbauer spectroscopy, and dynamic light scattering (DLS). Biocompatibility was evaluated in-vitro using cultured mouse embryonic fibroblasts (MEFs). The results show us an increasing of IC from 0.110 mg/mL for Fe₃O₄ NPs to 0.405 mg/mL for Fe₃O₄-Carborane NPs. The obtained data confirm the biocompatibility and stability of synthesized NPs and the potential to use them in BNCT.
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http://dx.doi.org/10.3390/nano9040494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6523109PMC
March 2019

Correlation Between Composition and Electrodynamics Properties in Nanocomposites Based on Hard/Soft Ferrimagnetics with Strong Exchange Coupling.

Nanomaterials (Basel) 2019 Feb 4;9(2). Epub 2019 Feb 4.

Department of Nano-Medicine Research, Institute for Research & Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, P.O. Box 1982, 31441 Dammam, Saudi Arabia.

In this work, SrBaPbFeO/(CuFe₂O₄) (x = 2, 3, 4, and 5) as strongly exchange-coupled nanosized ferrites were fabricated using a one-pot sol⁻gel combustion method (citrate sol-gel method). The X-ray diffraction (XRD) powder patterns of the products confirmed the occurrence of pure, exchange-coupled ferrites. Frequency dependencies of the microwave characteristics (MW) were investigated using a co-axial method. The non-linear behavior of the MW with the composition transformation may be due to different degrees of Fe ion oxidation on the spinel/hexaferrite grain boundaries and strong exchange coupling during the hard and soft phases.
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http://dx.doi.org/10.3390/nano9020202DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6409981PMC
February 2019

Preparation and morphology-dependent wettability of porous alumina membranes.

Beilstein J Nanotechnol 2018 15;9:1423-1436. Epub 2018 May 15.

L. N. Gumilyov Eurasian National University, Abylaykhan, 2/1, Astana 010008, Kazakhstan.

This article presents the preparation and study of the wetting properties of porous alumina membranes (PAMs) with a thickness of 25 to 75 μm and with a different pore sizes. The fabrication process features, scanning electron microscopy and atomic force microscopy characterization results are presented. The comparative analysis of PAM surfaces (outer and inner) and the effect of morphology of these surfaces on the wetting properties are discussed. Both alumina surfaces show significant morphology-dependent wettability. Measurements of the interfacial contact angle were made on the as-fabricated amorphous membrane and after pore widening with a range of pore diameters from 25 to 100 nm. The possible applications of PAMs for various membrane technologies is shown.
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http://dx.doi.org/10.3762/bjnano.9.135DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6009415PMC
May 2018
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