A5075329423- Bone Tissue Engineering Materials
- Petroleum Processing and Analysis
- Luminescence Properties of Advanced Materials
- NMR spectroscopy and applications
- Electron Spin Resonance Studies
- Solid-state spectroscopy and crystallography
- Chemical Synthesis and Characterization
- Hydrocarbon exploration and reservoir analysis
- Advanced NMR Techniques and Applications
- Diamond and Carbon-based Materials Research
- Inorganic Fluorides and Related Compounds
- X-ray Diffraction in Crystallography
- Radioactive element chemistry and processing
- Physics of Superconductivity and Magnetism
- Crystal Structures and Properties
- Crystallization and Solubility Studies
- Semiconductor materials and devices
- Enhanced Oil Recovery Techniques
- Quantum optics and atomic interactions
- Spectroscopy and Quantum Chemical Studies
- Free Radicals and Antioxidants
- Electrochemical Analysis and Applications
- Lanthanide and Transition Metal Complexes
- Magnetic properties of thin films
- biodegradable polymer synthesis and properties
Kazan Federal University
2016-2025
Institute of Physics
2016-2025
Czech Academy of Sciences, Institute of Physics
2021-2023
Goethe University Frankfurt
2008-2012
Goethe Institute
2009-2012
Justus-Liebig-Universität Gießen
2004-2006
Dynamic nuclear polarization (DNP) at high magnetic fields (9.2 T, 400 MHz 1H NMR frequency) requires microwave power sources to achieve saturation of the EPR transitions. Here we describe first high-field liquid-state DNP results using a high-power gyrotron source (20 W 260 GHz). A enhancement −29 on water protons was obtained for an aqueous solution Fremy's Salt; in comparison previous highest value −10 solid-state (maximum 45 mW). The increased enhancements are partly due larger and...
Unexpected high DNP enhancements of more than 10 have been achieved in liquid water samples at room temperature and magnetic fields 9.2 T (corresponding to 400 MHz 1H NMR frequency 260 GHz EPR frequency). The were polarized situ using a double-resonance structure, which allows simultaneous excitation transitions achieves significant very low incident microwave power only 45 mW. These results demonstrate the first important step toward application high-resolution NMR, increasing sensitivity...
A series of 12 asphaltene samples extracted from heavy oils and the oxidized bitumen different origin has been studied with high-frequency W-band (94 GHz) pulsed electron paramagnetic resonance (EPR) spectroscopy. Transverse (T2e) longitudinal (T1e) relaxation times free radical (FR) vanadyl porphyrin (VO2+) were measured for each sample. significant contribution spectral diffusion to T2e revealed ascribed dipole–dipole interaction between FR VO2+. This indicates that distance VO2+ does not...
Succeeding in the substitution of pharmaceutical compounds with ions deliverable use resorbable biomaterials could have far-reaching benefits for medicine and economy. Calcium phosphates are known as excellent accommodators foreign ions. Manganese, fifth most abundant metal on Earth was studied here an ionic dopant β-tricalcium phosphate (β-TCP) ceramics. β-TCP containing different amounts Mn2+ per MnxCa3–x(PO4)2 formula (x = 0, 0.001, 0.01, 0.1) investigated a range physicochemical...
Upgrading of heavy oil in supercritical water (SCW) was analyzed by a comprehensive analysis GC, GC–MS, NMR, and SEM–EDX with the aid electron paramagnetic resonance (EPR) as complementary technical analysis. The significant changes physical properties chemical compositions reveal effectiveness upgrading SCW. Especially, intensities conventional EPR signals from free radicals (FRs) vanadyl complexes (VO2+) SCW treatment were noticed, they explained, respectively, to understand sulfur removal...
This paper focuses on the search for desired thickness of 10B4C thin-film coating, as well macrostructuring aluminum foil substrate used a cathode in production multiwire gas detector thermal neutrons. The impact film from 1.0 to 2.5 μm and 0.05 mm thick Λ-shaped macrostructured with an angle at Λ-vertex 10 45 degrees, height 0.5 4 distance between Λ-structures 0.1 0.8 relative units neutron registration efficiency 1.8Å, was investigated. Numerical modeling electrostatic field carried out...
The research focuses on the explanation of a phenomenon observed in spectra electron nuclear resonance (ENDOR) pertaining to nitrogen atoms adjacent boron vacancy (VB) defect hexagonal nitride (hBN). is manifested as shift ENDOR spectrum lines with respect Larmor frequency. It hypothesized that these shifts are indicative substantial hyperfine interaction between VB and 14N nuclei hBN. A calculation utilizing second-order perturbation theory was executed determine positions lines, resulting...
Quantum technologies are currently being explored for various applications, including computing, secure communication, and sensor technology. A critical aspect of achieving high-fidelity spin manipulations in quantum devices is the controlled optical initialization electron spins. This paper introduces a low-cost programming scheme based on 32-bit STM32F373 microcontroller, aimed at facilitating high-precision measurements optically active solid-state centers within semiconductor crystals...
The structural properties of crude oils and asphaltenes, especially related to the dynamics their aggregation, have been investigated by different experimental theoretical methods during last few decades. However, there are only a works devoted study asphaltenes in native hydrocarbon environment. In this report, we illustrate possibility use electron paramagnetic resonance (EPR) spectra vanadyl porphyrins for qualitative quantitative analysis rotational mobility oil samples. On basis...
Structural characterization of metalloporphyrins in complex systems such as native hydrocarbons is the focus scientific and industrial interests since many years. We describe electron-nuclear double resonance (ENDOR) crude oil from well without any additional sample treatment (i.e., environment) magnetic field about 3.4 T temperature 50 K by applying microwave pulses at 94 GHz (W-band) radiofrequency near proton Larmor frequencies 144 MHz to probe paramagnetic vanadyls. By means density...
Quantitative electron paramagnetic resonance (EPR) measurements were done on the alumina oxide surface by using 9,10-anthraquinone probe (AQ) with AQ amount in range of (0.5–20) wt %. The nature three centers observed simultaneously is ascribed to strong, medium, and weak Al Lewis acid sites basis combined EPR study/infrared (IR) spectroscopy adsorbed CO pyridine/temperature-programmed desorption (TPD) ammonia. It shown how optimal concentration molecule for exhaustive quantitative...
Mn-catalyzed oxidation of the Ashalcha heavy oil in porous media was examined. We used manganese(III) tris(acetylacetonate) as a convinient oil-soluble precatalyst that decomposes to catalytically active species during temperature ramping. Reaction kinetics with air indicated presence manganese ions changes mechanism process, especially high-temperature region. To study transformations detail, we suggested approach combining X-ray powder diffraction (XRPD), thermal analysis, non-isothermal...
We demonstrate the application of combined experimental-computational approach for studying anionic impurities in hydroxyapatite (HAp). Influence carbonation level (x) on concentration NO3(2-) radicals HAp nanocrystals Ca10-xNax(PO4)6-x(CO3)x(OH)2 with x range 0 < 2 and average sizes 30 nm is investigated by different analytical methods including electron paramagnetic resonance (EPR). Stable are formed under X-ray irradiation nano-HAp samples from NO3(-) ions incorporated trace amounts...
We present a detailed study of electron/nuclear interaction in specific crude oil by continuous-wave and pulsed EPR, electron–nuclear double resonance (ENDOR) at W-band (94 GHz), fast field-cycling dynamic nuclear polarization (FFC-DNP) X-band. A perceptible non-Overhauser (solid) effect is found room temperature as result the transfer from intrinsic "free" radicals to 1H nuclei with different dynamics. On basis analysis longitudinal relaxation times, three dynamical components described...
Bioactive manganese (Mn)-doped ceramic coatings for intraosseous titanium (Ti) implants are developed. Arc plasma deposition procedure is used preparation. X-ray Diffraction, Scanning Electron Microscopy-Energy Dispersive Spectroscopy, and Paramagnetic Resonance (EPR) methods applied characterization. The homogeneous, composed of the main phase α-tricalcium phosphate (α-TCP) (about 67%) minor hydroxyapatite 33%), Mn content 2.3 wt%. EPR spectroscopy demonstrates that ions incorporated in TCP...
Mesoporous hydroxyapatite (HA) and iron(III)-doped HA (Fe-HA) are attractive materials for biomedical, catalytic, environmental applications. In the present study, nanopowders of Fe-HA with a specific surface area up to 194.5 m2/g were synthesized by simple precipitation route using iron oxalate as source Fe3+ cations. The influence amount on phase composition, powders morphology, Brunauer–Emmett–Teller (BET) (S), pore size distribution investigated, well electron paramagnetic resonance...
Mesoporous iron-doped hydroxyapatite (HA) powders with a surface area up to 141 m2/g were synthesized and characterized by variety of analytical computational approaches, including X-ray diffraction (XRD) fluorescence spectroscopy (XRF), atomic emission spectrometry inductively coupled plasma (AES-ICP), Fourier transform infrared absorption (FTIR), nitrogen adsorption–desorption (BET), scanning transmission electron microscopy (SEM TEM), paramagnetic resonance (EPR), density functional...
Our knowledge of electromagnetic heating’s effect on heavy oil upgrading is largely based very limited data. The aim the present research was thus to study in detail microwave exposure absence and presence nanosized magnetite composition oil. obtained data reveal that use improves not only radiation application as a result its absorption release thermal energy but also these nanoparticles have catalytic ability break carbon–heteroatom bonds resins asphaltene molecules. In fact, overall...