The electronic, magnetic, optical and elastic properties of nanomaterials are governed partially by the crystallite size and crystal defects. Here, the crystalline size of hexagonal La_1−xSr_xMnO₃ (x = 0.3) nanoparticles was determined using various methods. Single-phase La_0.7Sr_0.3MnO₃ nanopowders were produced after 10 h of milling in a commercial high-energy SPEX 8000D shaker mill, and then they were heated at 700 °C and 800 °C to study the effect of calcined temperature on the crystallization of nanoparticles. The modified Scherrer, Williamson–Hall, size–strain, and Halder–Wagner methods were used to determine the crystallite sizes and the elastic properties, such as intrinsic strain, stress, and energy density, from the X-ray diffraction peak broadening analysis. The obtained results were then compared with one another. The difference in crystallite sizes calculated from the different methods was due to the different techniques.

Schematic diagram of energy-band structure for MFe₂O₄ (M = Co, Fe, Mn) nanoparticles.

This work investigates the structure, optical and electrical conductivity properties of BaTi_1−xCo_xO₃ (0≤ x ≤0.1) ceramics prepared by the hydrothermal method.

Externally regulated and stimuli-responsive drug delivery systems remain of significant interest for improving the controllability of cancer treatment strategies. In this study, APTES-functionalized Gd_0.18Fe_2.82O₄@SiO₂ core–shell nanoparticles were developed as a pH- and magnetically responsive platform for doxorubicin (DOX) delivery. Structural and morphological characterization confirmed quasi-spherical nanoparticles with mesoporous silica shells and satisfactory colloidal stability under physiological conditions. FTIR analysis indicated successful DOX adsorption mediated by electrostatic interactions and hydrogen bonding with amino-functionalized surfaces. The system achieved a DOX loading efficiency of 82.6% at pH 7.4, and adsorption kinetics followed a pseudo-second-order model. In vitro release studies demonstrated pronounced pH-dependent behavior, with enhanced drug release under acidic conditions. Upon exposure to an alternating magnetic field (200 Oe, 450 kHz), efficient magnetothermal heating was induced, enabling rapid and externally regulated enhancement of DOX release. Cytotoxicity assays showed negligible intrinsic toxicity of the unloaded carrier under the tested conditions, while the DOX-loaded nanoparticles induced concentration-dependent cytotoxic effects in HepG2 and MCF-7 cells (IC₅₀ ≈ 50 µg mL⁻¹ for the carrier, corresponding to ∼2.6–2.7 µg mL⁻¹ DOX equivalent). AMF-mediated heating resulted in temperature-dependent loss of cell viability, exceeding 90% at 55 °C within 10 min. Overall, the Gd_0.18Fe_2.82O₄@SiO₂/APTES/DOX system demonstrates alternating magnetic field (AMF)-responsive drug release and pronounced temperature-dependent cytotoxicity, supporting its potential for chemo-magnetic cancer treatment.

In this study, we investigated the critical behavior of La₀.₇Ca₀.₂₅Ag₀.₀₅MnO₃ nanoparticles by analyzing temperature-dependent resistivity data and systematic magnetization measurements performed under an applied magnetic field of 3 T. The critical exponents extracted from the resistivity scaling near the ferromagnetic–paramagnetic transition, β = 0.676 and γ = 0.734, closely match those obtained from the Modified Arrott plot method, demonstrating good internal consistency between electrical transport and magnetic characterization approaches. To further assess the reliability and universality of the extracted exponents, the Widom scaling relation was employed, alongside a detailed examination of the magnetization scaling equations. Both analyses confirmed that the critical behavior satisfies the expected scaling constraints over a broad temperature and field range. The convergence of these independent methods provides strong evidence that long-range dipole–dipole interactions play a dominant role in governing the magnetic phase transition of La₀.₇Ca₀.₂₅Ag₀.₀₅MnO₃ nanoparticles, offering deeper insight into the mechanisms controlling their magnetic and transport properties.