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This study investigates the complex investigation of the 0-3 particulate multiferroic properties found in composite materials. The materials used in this study are (1 - x)Ba0.85Sm0.15TiO3 (SmBT)-xCo0.85Sm0.15Fe2O4 (SmCF), and the research utilizes a combination of the solid-state reaction method and mechanical milling techniques. A cubic spinel secondary phase was discovered in Co0.85Sm0.15Fe2O4, while a tetragonal structure was found in Ba0.85Sm0.15TiO3. The M-H loops clearly indicate the presence of exchange interactions between spins with varying orientations within the domains. As the proportion of SmCF in the composites increased, the saturation magnetization and magnetic moments became stronger, indicating a greater level of exchange interactions. Through a temperature-dependent analysis, an increase was observed in both the dielectric constant (εr) and dielectric loss (tan δ). Nevertheless, there was a decrease in εr above the Curie temperature. It is worth mentioning that there was a significant increase in the magnetoelectric coupling constant, suggesting a stronger interaction between magnetic and electric fields. This increased interaction leads to a more effective conversion of electrical energy into its magnetic equivalent, indicating a significant improvement in overall energy efficiency. The results of our study shed light on a promising direction for the development of advanced multifunctional materials, which could have significant implications for energy-efficient applications.
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Multiferroic composites exhibit remarkable magnetoelectric (ME) characteristics, offering diverse applications. The study investigated samarium (Sm) doped composites, specifically (1 -x)Ba0.5Sm0.5TiO3-xCo0.5Sm0.5Fe2O4(x= 0.0,0.02,0.04,0.06), formed by combining Sm doped BaTiO3and CoFe2O4using the solid-state reaction method. X-ray diffraction analysis revealed a tetragonal structure in Ba0.5Sm0.5TiO3(SmBT) and a cubic spinel secondary phase in Co0.5Sm0.5Fe2O4(SmCF), suggesting uniform distribution of grains. The optical bandgap in SmBT and the composite showed a slight decrease (from 3.14 eV to 3.01 eV) with increasing Sm concentration, as observed in optical studies. The dielectric measurements showed that the dielectric constant of SmBT was higher (ϵ'= 526.3) between 80 Hz and 8 MHz, while the composites had a lower dielectric constant (ϵ'= 438.4) at lower frequencies and the real part of dielectric was fitted by Havriliak-Negami (H-N) model shows that the dielectric curves exhibit a characteristic dispersion pattern known as the cole-cole mode (grains) also confirmed by cole-cole plot. The response exhibited linearity, adhering to the universal dielectric response model. Ferroelectric behaviour in the underlying material confirms SmBT non-centrosymmetric character and the storage efficiency (η) of all composites surpassed 90%, reaching a peak of 94.8% with a ferrite content of 0.02. The versatility of the Sm-doped composites offers opportunities for diverse applications in fields such as electronics, telecommunications, and biomedical devices. Notably, these materials can be utilized in Memory Devices, Actuators, and other relevant applications.
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BACKGROUND: Contact dermatitis (CD) is a frequently occurring medical condition, for which Vinca minor (VM) is one of the recommended homeopathic medicines. However, the symptoms indicating this medicine have not yet been assessed systematically. Likelihood ratio (LR), based on Bayesian statistics, may yield better estimation of a medicine's indication than the existing method of entry of symptoms into materia medica and repertories. METHODS: We investigated LRs of four CD symptoms of VM: (1) great sensitiveness of skin, with redness and soreness from slightest rubbing; (2) weeping eczema with foul, thick crusts; (3) itching amelioration in open air; and (4) CD of scalp. An observational, prospective, patient-outcome study was conducted in five different practice settings on 390 CD patients over 18 months using three outcomes-Glasgow Homeopathic Hospital Outcome Scale (GHHOS), Scoring Atopic Dermatitis (SCORAD), and Dermatology Life Quality Index (DLQI), assessed at baseline, after 3 and 6 months. The LR of each of the four symptoms was estimated as per the patient-rated outcomes on GHHOS. RESULTS: Seventy-four VM and 316 non-VM cases were analyzed. Estimated LRs were as follows: symptom 1, 1.29 (95% confidence interval [CI]: 0.65 to 2.60); symptom 2, 1.48 (95% CI: 0.80 to 2.74); symptom 3, 1.70 (95% CI: 0.94 to 3.07); symptom 4, 1.36 (95% CI: 0.74 to 2.51). There were statistically significant reductions in SCORAD and DLQI scores over 3 and 6 months. CONCLUSION: There was insufficient evidence to attribute any of the four assessed symptoms clearly to VM. Though non-significant, a high LR was observed for "itching amelioration in open air" (symptom 3). Symptoms in the homeopathic materia medica for VM are perhaps over-represented. More research of this nature is warranted.
