Жарияланымдар / Публикации
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- Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Магнитные свойства композита частиц DyMn-=SUB=-2-=/SUB=-O-=SUB=-5-=/SUB=--Mn-=SUB=-3-=/SUB=-O-=SUB=-4-=/SUB=-(Ioffe Institute, 2020-12-15); ; ; ; A. T. KezdikbaevaThe paper presents the results of the experimental studies of magnetic and resonance properties of the DyMn2O5 – Mn3O4 particles composite. There are two magnetic transitions at temperatures T1 65 K and T2 230 K. T1 differs from the transition temperatures for the initial materials, and this fact is associated with the interparticle interaction. T2 corresponds to the impurity phase DyMnO3 (1 at.%). Three peaks of microwave absorption are observed in the magnetic resonance spectrum, which is explained in the framework of the model of a two-phase system in magnetic relation. One resonance is attributed to Mn3O4 and the other two peaks refer to the ensemble of strongly anisotropic DyMn2O5 particles with a random distribution of anisotropy axes. Patrin Gennady Semionovich1,3 Mataev Mukhametkali Musagalievich2 Abdraimova Moldir Rashidovna2 Tursinova Zhanar Iliyasovna2 Kezdikbaeva Asel Taupykovna4 Shiyan Yaroslav Germanovich1,3 Plekhanov Vasil Granitovich1 1 Siberian Federal University, Svobodny pr. 79, Krasnoyarsk, 660041, Russia 2 Kazakh State Women’s Teacher Training University, Aiteke bi, 99, Almaty, 050000, Kazakhstan 3 L.V. Kirensky Institute of Physics, Federal Research Center KSC, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036 Russia 4 E.A. Buketov Karaganda State University, st. University 28, City of Karaganda, 100028, Kazakhstan - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, СИНТЕЗ И СТРУКТУРА МАНГАНИТА Bi 0.3 Dy 0.7 Mn 7 O 12Manganite with mixed complex oxides Bi 0.3 Dy 0.7 Mn 7 O 12 was synthesized by the furnace method. The Pechini method used urea as a complexing agent. The composition and structure of the synthesized manganite were determined experimentally. For the first time, the structure, the type of the syngony, the parameters of the unit cells, the x-ray diffraction density of the manganite were determined by X-ray phase analysis: a = 7.5472, b = 8.5244, c = 5.7836 A, V un.cell. = 372.090A 3 , Z = 4, ρ rad. = 7,120 g / cm 3 , ρ pyc. = 7.09 g / cm 3 . The pycnometric density was measured 5-6 times and the data were averaged. Toluene served as an indifferent fluid. - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Magnetic Properties of the DyMn2O5–Mn3O4 Nanoparticle Composite(Pleiades Publishing, 2021-04-01); ; ; ; A. T. KezdikbaevaAbstract The magnetic and resonance properties of the DyMn2O5–Mn3O4 nanoparticle composite have been experimentally investigated. Two magnetic transitions at temperatures of T1 ≈ 65 K and T2 ≈ 230 K have been established; the T1 value differs from the temperatures of the transitions in the initial materials, which has been attributed to the interparticle interactions. Temperature T2 corresponds to the DyMnO3 impurity phase (1 at %). Three microwave absorption peaks have been observed in the magnetic resonance spectrum, which is explained within the model of a magnetically two-phase system. One resonance is attributed to Mn3O4, and the other two peaks are attributed to an ensemble of highly anisotropic DyMn2O5 particles with a random distribution of anisotropy axes.Цитирования (OpenAlex) 3Цитирования (OpenCitations) 2 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Synthesis and magnetic properties of Y0,5Ca0,5Cr0,5Mn0,5O3 compoundsIn this work,a solid solution of chromite-manganite of the composition Y0,5Ca0,5Cr0,5Mn0,5O3 was synthesized using the sol-gel method. Based on the results of experimental studies of the magnetostatic properties of the polycrystalline system Y0,5Ca0,5Cr0,5Mn0,5O3. It is found that the predominant is the intracrystalline ferromagnetic interaction, while the intercrystalline interaction is antiferromagnetic in nature.In the field of 2000 Oe and 5000 Oe at a temperature of 5 K, the magnetic moment is not even positive. These dependencies were obtained after the sample was in a large negative field. This initial moment is approximately equal to the residual moment on the hysteresis loop for a temperature of 5 K. When the external field is increased gradually, for example, in increments of 250 Oe, this moment increases to 1.2 emu/g at 2000 Oe. Based on the results of magnetostatic measurements, it was found that hysteresis loops of magnetization are observed at low temperatures. - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Synthesis, Structure, and Electrophysical and Electrochemical Properties of Novel Composite La0.9MnO3-LaFeO3(Multidisciplinary Digital Publishing Institute, 2024-12-31); ; ; This article presents the synthesis, electrophysical, and catalytic properties of a La0.9MnO3–LaFeO3 nanocomposite material. The nanocomposite was synthesized via the sol–gel (Pechini) method. X-ray diffraction (XRD) analysis revealed a polycrystalline, biphasic perovskite structure combining both hexagonal and cubic symmetry. The microstructure and elemental composition, examined using field emission scanning electron microscopy (FESEM), indicated an average particle size of approximately 186.9 nm. The composite exhibits semiconducting behavior within the temperature ranges of 293–323 K and 343–393 K. Developing electrocatalysts free of precious metals for the hydrogen evolution reaction (HER) is increasingly important to facilitate the production of hydrogen from renewable sources. In this study, the conductive La0.9MnO3–LaFeO3 composite was deposited on graphite and, for the first time, evaluated as an electrocatalyst for HER in acidic media. The resulting composite films were tested using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) in a glassy carbon electrode (GCE) setup, providing insights into their potential as effective, cost-efficient electrocatalysts.Цитирования (OpenAlex) 9Цитирования (OpenCitations) 8 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Novel Spinel Li–Cr Nano-Ferrites: Structure, Morphology, and Electrical/Dielectric Properties(Multidisciplinary Digital Publishing Institute, 2025-10-26); ; ; ; This article reports on the synthesis and physicochemical characterization of a novel complex ferrite material, LiCr3.4Fe1.6O8, prepared via the sol-gel method. X-ray diffraction (XRD) analysis confirmed that the synthesized compound is a single-phase material with a spinel-type structure and cubic symmetry. Raman spectroscopy was employed to investigate the vibrational modes, and the observed peaks corresponding to Fe–O and Cr–O bonds further validated the spinel-like structure of the compound. The microstructure and elemental composition were examined using scanning electron microscopy (SEM). Multiple regions of the LiCr3.4Fe1.6O8 crystals were analyzed, revealing a homogeneous phase and providing detailed insight into the morphology and chemical composition of the surface. The synthesized ferrite particles exhibited relatively large dimensions, with sizes measured at approximately 5, 30, 100, and 200 μm. The dielectric behavior was studied to assess the material’s response to an external electric field, demonstrating its capacity for electric charge polarization. Both capacitance and electrical conductivity were found to increase with rising temperature. Electrophysical measurements were conducted using the LCR-800 system over a temperature range of 293–483 K and at frequencies of 1.5 kHz and 10 kHz. An increase in frequency to 10 kHz resulted in a decrease in the dielectric constant (ε) across the entire temperature range.Цитирования (OpenAlex) 3Цитирования (OpenCitations) 1 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Structure Property–Application Relationships of Spinel Ferrite Nanoparticles: From Synthesis to Functional Systems(Multidisciplinary Digital Publishing Institute, 2026-02-24); ; ; ; Krishnamoorthy Ramachandran). The physicochemical principles, advantages, and limitations of various synthesis techniques-including co-precipitation, combustion, sol-gel, thermal decomposition, hydrothermal, solvothermal, microwave-assisted, sonochemical, electrochemical, and solid-state reaction methods-are comparatively discussed. The influence of synthesis parameters on crystal structure, morphology, and cation distribution between tetrahedral and octahedral sites, as well as on magnetic, dielectric, and optical properties, is critically analyzed. Furthermore, the capabilities of characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS), Fourier-transform infrared spectroscopy (FTIR), FT-Raman spectroscopy, dielectric measurements, and magnetic measurements for investigating spinel ferrites are comprehensively summarized. Finally, the high potential of spinel ferrite nanoparticles for applications in electronics, microwave devices, water treatment, catalysis, sensors, and biomedical fields is highlighted.Цитирования (OpenAlex) 28 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, FeMnO3: Synthesis, Morphology, Dielectric Properties, and Electrochemical Behavior Toward HER by LSV(Multidisciplinary Digital Publishing Institute, 2026-02-27); ; ; - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Laboratory Affordances for Early-Stage Pedagogical Content Knowledge Development in Chemistry Teacher Education: A Comparative Qualitative Case Study in Kazakhstan and Türkiye(Multidisciplinary Digital Publishing Institute, 2026-04-17); ; ; Laboratory courses in chemistry teacher education are commonly framed as spaces for mastering experimental procedures; however, they may also function as pedagogical environments where pre-service teachers begin integrating content knowledge (CK) with pedagogical knowledge (PK). Rather than measuring Pedagogical Content Knowledge (PCK) as an outcome, this comparative study examines how laboratory structures create opportunities for CK–PK integration and PCK-related reasoning in chemistry teacher education programs in Kazakhstan and Türkiye. A qualitative comparative case study design was employed. Data were collected through 60 h of in situ observations and semi-structured interviews with 46 third-year pre-service chemistry teachers at two public universities. The analysis focused on how laboratory organization, instructional facilitation, time allocation, assessment, and material resources shape conditions for analytical and reflective engagement. Findings identify four interrelated dimensions of laboratory affordances: structural organization, pedagogical facilitation, experiential engagement, and reflective regulation. Extended laboratory sessions and dedicated laboratory credits in the Turkish case supported sustained inquiry and reflection, whereas shorter, combined lecture–laboratory formats in the Kazakhstani case constrained extended pedagogical reasoning. The proposed Laboratory Affordance Model highlights how laboratory design influences early-stage PCK-related reasoning, offering implications for curriculum design and chemistry teacher education policy.Цитирования (OpenAlex) 1 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Synthesis and electrophysical characterization of a three-phase Ca–Nd–Mn–Ni–O oxide system(Nature Portfolio, 2026-06-25)Цитирования (OpenAlex) 1