Effect of heat treatment on the structural parameters and magnetic properties of copper ferrite nanopowders obtained by the sol-gel combustion

Phase composition, structure parameters and basic magnetic characteristics obtained by the sol-gel combustion nanopowders of ferrospinel CuFe2O4 are investigated. A comparison of the properties of synthesized materials: first sample - immediately after the combustion of the gel and second sample - after annealing at 1073 K for 4 hours are performed. Annealing leads to an increase in the concentration of the phase with tetragonal crystal structure. Particle sizes and the value of anisotropy field of this phase also increased

Study of the magnetic anisotropy of the multiphase samples of the ferrimagnets with hexagonal crystal structure by the method of ferromagnetic resonance

The influence of machining conditions in a planetary ball mill on the phase composition, structural and magnetic parameters of hexaferrite powders composition BaFe12O19 was investigated. The properties of powders vary greatly depending on the power density and the time of machining. Magnetocrystalline anisotropy of multiphase powders was studied by the method of ferromagnetic resonance. The effective field of magnetic anisotropy is reduced by more than two times, with decreasing particle size of ~ 67 nm to ~ 10 nm when the processing time equal to 10 minutes. The flow of mechanochemical reactions during grinding leads to the disintegration of the hexagonal crystal phase and the formation of the magnetite phase with a small value of the magnetocrystalline anisotropy field

Radiation-thermal synthesis of W-type hexaferrites

The results of investigations of the phase composition, structural parameters, static and dynamic magnetic properties of BaCo0.7Zn1.3Fe16O27 hexaferrites obtained by the method of self-propagation high-temperature synthesis in combination with mechanochemical activation and radiation-thermal post-sintering are presented. The prospects of the proposed energy-saving approach for the production of ferrite ceramics with a hexagonal structure is shown

Влияние глубокого рыхления междурядий на физические свойства дерново-подзолистой почвы и урожайность органического картофеля

The purpose of this research is to study the effect of deep loosening of row spacings on the physical properties of the soil and yield of organic potatoes. Two variants of soil cultivation were used in row spacings: usual and 25 cm deep. The soil cultivation was carried out with a row-crop chisel cultivator. Its design was developed at the institute. Analysis of the data obtained as a result of experimental studies showed that deep loosening of row spacings had a positive effect on soil compaction both in the inter-row width and directly in the plough ridge. The soil compaction in the row spacing during normal tillage was in average above 20 %, and in the ridge by an average of 13 % compared to deep tillage. The assimilation of moisture by the soil with when using of deep loosening of row spacings also had a positive trend, especially under condition of a large amount of precipitation in a short period of time. Thus, with a loss of 34 mm, the soil in the variant with loosening the row spacings in a larger volume absorbed moisture and the moisture indicators increased sharply in layers, at 15 cm by 27 %, at 25 cm by 20 %, at 35 cm by 5 %. Potato yield increased by 8.7 % when using deep loosening of row spacings. The obtained results of experimental studies should be used as recommendations when carrying out technological operations aimed at caring for potato plantings.Целью данного исследования является изучение влияния глубокого рыхления междурядий на физические свойства почвы и урожайность органического картофеля. В междурядьях использовалось два варианта обработки почвы: обычный и на глубину 25 см. Обработка почвы проводилась с помощью пропашного культиватора-глубокорыхлителя, конструкция которого разработана в ИАЭП. Анализ данных, полученных в результате экспериментальных исследований, показал, что глубокое рыхление междурядий положительно сказалось на уплотнении почвы как по ширине междурядий, так и непосредственно в гребне. Уплотнение почвы в междурядьях при обычной обработке почвы было в среднем выше 20 %, а на гребне в среднем на 13 % по сравнению с глубокой обработкой почвы. Усвоение влаги почвой с использованием глубокого рыхления междурядий также имело положительную динамику, особенно в условиях выпадения большого количества осадков за короткий промежуток времени. Таким образом, при выпадении 34 мм почва в варианте с рыхлением междурядий в большем объеме усвоила влагу и показатели влажности резко повысились в слоях, на 15 см – на 27 %, на 25 см – на 20 %, на 35 см – на 5 %. Урожайность картофеля увеличилась на 8,7 % при использовании глубокого рыхления междурядий. Полученные результаты экспериментальных рекомендуется использовать при проведении технологических операций, направленных на уход за посадками картофеля

Prussian Blue Nanozymes with Enhanced Catalytic Activity: Size Tuning and Application in ELISA-like Immunoassay

Prussian blue nanozymes possessing peroxidase-like activity gather significant attention as alternatives to natural enzymes in therapy, biosensing, and environmental remediation. Recently, Prussian blue nanoparticles with enhanced catalytic activity prepared by reduction of FeCl3/K3[Fe(CN)6] mixture have been reported. These nanoparticles were denoted as ‘artificial peroxidase’ nanozymes. Our study provides insights into the process of their synthesis. We studied how the size of nanozymes and synthesis yield can be controlled via adjustment of the synthesis conditions. Based on these results, we developed a reproducible and scalable method for the preparation of ‘artificial peroxidase’ with tunable sizes and enhanced catalytic activity. Nanozymes modified with gelatin shell and functionalized with affine molecules were applied as labels in colorimetric immunoassays of prostate-specific antigen and tetanus antibodies, enabling detection of these analytes in the range of clinically relevant concentrations. Protein coating provides excellent colloidal stability of nanozymes in physiological conditions and stability upon long-term storage. © 2022 by the author. Licensee MDPI, Basel, Switzerland.Russian Science Foundation, RSF: 20-75-00029Funding: This study was supported by the Russian Science Foundation, grant 20-75-00029

Application of NMR for quantification of magnetic nanoparticles and development of paper-based assay

H1 NMR relaxometry is a method that is extremely sensitive to the presence of magnetic nanoparticles, which significantly affect the transverse relaxation time of the water proton. Accordingly, the use of magnetic nanoparticles as labels allows detection of even extremely small amounts of the test substance. This paper analyzes the prospects for applying the method of solid-phase NMR-relaxometric determination of biologically active molecules. The nitrocellulose membranes are chosen as a solid phase and nanoparticles based on iron core with a carbon shell are used as magnetic labels. The possibility of detecting small concentrations of magnetic particles in porous medium is demonstrated. Finally, the ability to detect extremely low concentrations of an analyte, in this case, streptavidin protein (0.5 ng/ml to 100 ng/ml), which is actively used in various fields of biology and medicine, is demonstrated. © Published under licence by IOP Publishing Ltd.Russian Science Foundation, RSF: 17-15-01116The work was carried out within the Russian Science Foundation project 17-15-01116. equipment of the Ural Center for Shared Use Modern nanotechnology UrFU was used

Modified Desolvation Method Enables Simple One-Step Synthesis of Gelatin Nanoparticles from Different Gelatin Types with Any Bloom Values

Gelatin nanoparticles found numerous applications in drug delivery, bioimaging, immunotherapy, and vaccine development as well as in biotechnology and food science. Synthesis of gelatin nanoparticles is usually made by a two-step desolvation method, which, despite providing stable and homogeneous nanoparticles, has many limitations, namely complex procedure, low yields, and poor reproducibility of the first desolvation step. Herein, we present a modified one-step desolvation method, which enables the quick, simple, and reproducible synthesis of gelatin nanoparticles. Using the proposed method one can prepare gelatin nanoparticles from any type of gelatin with any bloom number, even with the lowest ones, which remains unattainable for the traditional two-step technique. The method relies on quick one-time addition of poor solvent (preferably isopropyl alcohol) to gelatin solution in the absence of stirring. We applied the modified desolvation method to synthesize nanoparticles from porcine, bovine, and fish gelatin with bloom values from 62 to 225 on the hundreds-of-milligram scale. Synthesized nanoparticles had average diameters between 130 and 190 nm and narrow size distribution. Yields of synthesis were 62–82% and can be further increased. Gelatin nanoparticles have good colloidal stability and withstand autoclaving. Moreover, they were non-toxic to human immune cells. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Funding: The reported study was funded by RFBR and Kaliningrad Oblast according to the research project № 19-415-393005 (preparation of fluorescence gelatin nanoparticles and study of their fluorescent properties), by RFBR research project 19-015-00408 (preparation of gelatin nanoparticles by the desolvation method), and by Ministry of Science and Higher Education of the Russian Federation within the framework of the Russian State Assignment under contract No. AAAA-А19-119112290010-7 (assessment of nanoparticles cytotoxicity)

Comparative studying of hemodynamics and segmental left ventricular contraction in patients with different treatment methods of ACS without ST-segment elevation

Main aim of our work was dynamic studying a condition of peripheral, central haemodynamics and left ventricular segmentary function at patients with various variants of therapy of ACS and get correlation in received data. 196 patients have been included in research with diagnosis ACS without ST elevation in the age from 39 years to 74 (103 men, and 93 women). All patients was examined for indicators of haemodynamics and segmentary contraction of heart in the first days of hospitalisation, then for 3.14 days, also in 3 and 6 months.Основной целью нашей работы являлось динамическое изучение состояние периферической, центральной гемодинамики и сегментарной функции левого желудочка у больных с различными вариантами терапии ОКС и провести по возможности корреляцию между полученными данными. В исследование были включены 196 больных с диагнозом OKCБПST в возрасте от 39 лет до 74. Из них 103 мужчины, и 93 женщины. Всем пациентам проводились оценка показателей гемодинамики и сегментарного сокращения сердца в первые сутки госпитализации, затем на 3,14 сутки, также через 3 и 6 месяцев

Experience of application ivabradine at patients with astable stenocardia in the combination to the metabolic syndrome

Aim: to estimate efficiency of application ivabradine at patients with an astable stenocardia in a combination to a metabolic syndrome in the presence of hyperdynamic type of blood circulation. 90 patients have been included in research with established diagnosis an astable stenocardia. Haemodynamics type evaluated by integrated rheovasography method with ‘Diamant M’ device. Conclusions: 1. Ivabradine it is represented a perspective drug for the control of frequency of heart rate at patients with an astable stenocardia in a combination to a metabolic syndrome in the presence of hyperdynamic type of blood circulation. 2. The combination p-blockers with ivabradine allows to lower a dose p-blockers for achievement of optimum frequency of heart rate.Цель работы: оценить эффективность применения ивабрадина у больных ИБС нестабильной стенокардией в сочетании с метаболическим синдромом при наличии гипердинамического типа кровообращения. В исследование были включены 90 пациентов с установленным диагнозом ИБС нестабильная стенокардия. У пациентов определялся тип гемодинамики методом интегральной реовазографии аппаратом «Диамант-М». Выводы: 1. Ивабрадин представляется перспективным препаратом для контроля частоты сердечных сокращений у пациентов с ИБС нестабильной стенокардией в сочетании с метаболическим синдромом при наличии гипердинамического типа кровообращения. 2. Сочетание p-адреноблокатора с ивабрадином позволяет снизить дозу p-адреноблокатора для достижения оптимальной частоты сердечных сокращений