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The effect of milling time on the nanostructure, thermal stability, thermomagnetic, and soft-magnetic properties of Fe72Ni8Co8Zr7B4Cu1 (at.%) upon mechanical alloying up to 72 h have been investigated. X-ray diffraction pattern of the milled powders predominately consists of peaks corresponding to the bcc α-Fe phase. The electron diffraction studies of the 72 h milled powder exhibited an equidistant ring pattern superimposed on a diffuse halo pointing the presence of both nanocrystalline and amorphous phases. After heat treatment, the 60 h milled powder showed the additional diffraction peaks of γ-Ni and bcc-Fe(Cu), corroborating the calorimetric and thermomagnetic analysis. The coercivities ( H C ) of powders improved with an increase in mill time. However, the H C of ball-milled powders was relatively high due to high lattice strain, particle surface roughness, as well as the shape and surface anisotropy of the powder particles. [ABSTRACT FROM AUTHOR]

Various magnetic materials (for example, ferro, ferri, antiferromagnetic) are characterized by their respective transition temperatures (for example, Curie and Néel transitions). Knowledge of these transition temperatures is vital from an application standpoint. Accurate measurements by suitable characterization techniques are needed for identifying these transitions. Several techniques have been used to identify Curie and Néel transition temperatures, with thermal methods being one of the preferred choice. These thermal methods include differential scanning calorimetry (DSC), differential thermal analysis, and thermogravimetric analysis. Although thermal analysis tools have been popularly used for examining magnetic phase transitions, still much confusion exists on their efficacy and might. This review article highlights the strength and limitations of measuring Curie and Néel transitions by thermal techniques; measurements by DSC were the most common choice in previous works. Considering the intrinsic/fundamental nature of these Curie/Néel transitions, such confusion on their measurements (by thermal techniques) and their subsequent analysis (for the order of transition) suggests that a more comprehensive understanding of the events should be an immediate future goal for the research community, at large. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Single phased α-(Fe 2 O 3) 1−X (Cr 2 O 3) X nanoparticles were prepared. • Band gap of Fe 2 O 3 is narrowed to 1.6 eV with addition of Cr. • Pectin was used as a gelling agent for Sol-gel synthesis. • Nanoparticles stabilised in corundum structure with R-3C space group. • Weak ferromagnetism was observed for the prepares α-(Fe 2 O 3) 1−X (Cr 2 O 3) X (0 ≤ x ≤ 1). Abstract We report on the tunable band engineering in α-(Fe 2 O 3) 1−X (Cr 2 O 3) X nanoparticles. Nanoparticles were prepared by the sol-gel method and stabilised in the hexagonal crystal structure with R-3C space group. At room temperature band-gap studies have shown the narrowing of the band gap from 2.1 eV to 1.6 eV with Cr addition. Compared to antiferromagnetic α-Fe 2 O 3 nanoparticles, doping of Cr 2 O 3 increases the magnetic hysteresis significantly. Impedance spectroscopic studies have revealed Maxwell-Wagner dielectric relaxation near room temperature. Our results improve the understanding of the structural, optical, dielectric and magnetic properties of Cr-doped α-Fe 2 O 3 nanoparticles and illustrates that these nanoparticles have potential candidate in spintronic, optoelectronic, solar cell and photocatalysis applications. [ABSTRACT FROM AUTHOR]

Background and objective Chronic kidney disease (CKD) is a clinical syndrome characterized by the irreversible loss of kidney function. It is a widespread condition affecting populations worldwide. The kidneys play a crucial role in the metabolism, breakdown, and elimination of thyroid hormone and thyroid-stimulating hormone (TSH). Consequently, thyroid dysfunction can occur as an endocrine manifestation in CKD patients. Previous studies investigating thyroid abnormalities and the severity of CKD have yielded diverse outcomes. In light of this, this study aimed to determine the prevalence of thyroid dysfunction in CKD patients and explore the association between different thyroid dysfunctions and markers of kidney function. Methods A total of 140 CKD patients who met the inclusion criteria were recruited, and their demographic details and routine investigations were recorded. Blood samples were collected for kidney function tests and thyroid function tests. The primary outcome measures included markers of kidney function [urea, creatinine, and estimated glomerular filtration rate (e-GFR)] and thyroid profile [TSH, free thyroxine (FT4), and free triiodothyronine (FT3)]. Mean and standard deviation (SD) were calculated for continuous variables, while frequencies were calculated for categorical data. Fisher's exact test was employed to evaluate the association between two categorical variables, and p-values below 0.05 were considered statistically significant. Results The mean (± SD) urea, creatinine, and e-GFR were found to be 139 (± 81.1) mg/dL, 5.33 (± 4.1) mg/dL, and 20.1 (± 15) ml/min/1.73 m 2 , respectively. Of note, 133 (95%) patients had elevated urea levels, with the majority (n = 109, 77.8%) having urea levels between 40 and 199 mg/dL; 70 (50%) patients had creatinine levels less than 4 mg/dL, and 107 (76.4%) had e-GFR of less than 30 ml/min/1.73 m 2 . The mean (± SD) TSH, FT4, and FT3 levels were found to be 6.64 (± 11.2) mIU/ml, 13.6 (± 4.54) pmol/L, and 2.65 (± 1.89) pmol/L, respectively. It was observed that 18 (12.9%, 95% CI: 8.29-19.4%) of the CKD patients had hypothyroidism and 21 (15%, 95% CI: 10.02-21.8%) had subclinical hypothyroidism (SCH), while only two (1.4%, 95% CI: 0.39-5.05%) and five (3.6%, 95% CI: 1.5-8.08%) had hyperthyroidism and subclinical hyperthyroidism, respectively. Thirty-nine (27.9%, 95% CI: 21.1-35.8%) patients had low FT4 levels, whereas a considerable majority (n = 123, 87.9%, 95% CI: 81.41-92.28%) of the patients suffering from CKD were found to have low FT3 levels. The associations of urea levels with SCH, low FT4, and FT3 status were found to be statistically significant with p-values of 0.002, 0.033, and <0.001, respectively. The association between e-GFR and low FT3 status was also statistically significant, with a p-value of 0.014. Conclusion Nine out of 10 patients with CKD were discovered to have low FT3 levels, whereas one in four patients had low FT4 levels. The study participants also exhibited a significant presence of SCH and hypothyroidism, with prevalence rates of 15% and 12.9%, respectively. Urea levels and e-GFR, indicating the severity of CKD, showed a significant association with the presence of various thyroid abnormalities. Hypothyroidism in CKD patients can complicate disease progression, impact mortality rates, and affect overall quality of life. Therefore, routine screening for thyroid abnormalities should be conducted in all CKD patients., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Raj et al.)