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Many physical properties behave differently in disorder systems from the order one. The effects of atomic disorder on the magnetic properties have been explored on Co2TiSi and Co2TiAl full Heusler alloys. Co2TiSi crystallizes in an ordered L21 crystal symmetry, and Co2TiAl mainly possesses a B2 structure. The B2 disorder affects not only the magnetic ordering but also the saturation magnetization, causing the deviation from the Slater-Pauling prediction for Co2TiAl. The critical exponents of the magnetic phase transition have been analyzed by employing different techniques like, the Arrott plot, Kouvel–Fisher plot, critical isotherm analysis, scaling magnetic behavior, and magnetocaloric analysis as well. The calculated critical exponents are close to the mean field theory which implies long-range ferromagnetic ordering in Co2TiSi. However, the exchange interaction in Co2TiAl deviates from the long-range mean field theory. This may be due to the magnetic contribution of the B2-disordered phase. In addition to the magnetic ordering, the magnetocaloric analysis provides the applicability of Co2TiSi alloy as a low-cost, hysteresis-free magnetic refrigerant with a large working temperature near room temperature. [ABSTRACT FROM AUTHOR]

The composites (x)CoFe2O4–(1−x)Ba0.8Sr0.2TiO3 are prepared by solid‐state reaction method using microwave double‐step sintering. Ba0.8Sr0.2TiO3 crystallizes to tetragonal crystal symmetry with P4mm space group and CoFe2O4 crystallizes to cubic crystal symmetry with Fd3¯m space group. Electron microscopy techniques are used to understand the microstructure, elemental composition, and morphology of the composites. The dielectric properties are measured in the 1 Hz–1 MHz frequency range and 40–400 °C temperature range. Composite with x = 0.1 (ε′ ≈ 170, tan δ = 0.08 at 1 kHz) and 0.2 (ε′ ≈ 390, tan δ = 0.07 at 1 kHz) has better dielectric properties than the parent Ba0.8Sr0.2TiO3 ferroelectric (ε′ ≈ 125, tan δ = 0.16 at 1 kHz) and CoFe2O4 ferrimagnetic phases (ε′ ≈ 375, tan δ = 0.72 at 1 kHz), respectively. Composite with 10% cobalt ferrite has the highest saturation polarization (2.1 μC cm−2), the highest remanent polarization (0.9 μC cm−2), and coercive field (23.9 kV cm−1) compared to ferroelectric phase followed by x = 0.2 composite (PS = 1.6 μC cm−2, Pr = 0.8 μC cm−2, and EC = 19.2 kV cm−1). Composite with x = 0.2 shows the highest magnetic coercive field of 1.96 kOe. Hence, this article advocates that 20% ferrite in the composites is the optimized composition for multiferroic applications. The present study will help to explore piezoelectric, magnetostrictive, and magnetoelectric properties of (x)CoFe2O4–(1−x)Ba0.8Sr0.2TiO3 for the technological application. [ABSTRACT FROM AUTHOR]

Gas-oil obtained from bitumen contains a significant amount of impurities, which are difficult to remove using a conventional alumina supported hydrotreating catalyst. Innumerable studies have been carried out to develop a highly effective hydrotreating catalyst, and among all utilizing more advanced support is considered as a better alternative. Recently, SBA-15 has received importance as a catalyst support because of its excellent textural properties. However, SBA-15 lacks surface acidity and provides very low metal–support interaction. By modifying SBA-15 with zirconia, an optimum level of surface acidity and Si–Mo interaction can be achieved. Also, by doping zirconia with SBA-15, the textural properties of zirconia can be improved. Hence, a synergistic effect can be obtained while incorporating zirconia onto SBA-15, and the resulting material Zr-SBA-15 can be used as an effective support for a hydrotreating catalyst. Zr-SBA-15 supports were prepared by the post synthesis and the direct synthesis method. Zr-SBA-15 supported NiMo catalysts were prepared by an incipient wetness impregnation technique. Catalysts and supports were characterized by SAXS, BET, XRD, TEM, SEM, ICP-MS, FTIR, and Raman spectroscopy methods. Characterization of support confirmed that the zirconia was successfully incorporated in a mesoporous SBA-15 structure without significantly changing the textural properties of SBA-15. The performance of the Zr-SBA-15 supported NiMo catalysts was evaluated based on hydrodesulfurization and hydrodenitrogenation activities exhibited during hydrotreating of heavy gas oil derived from Athabasca bitumen. The comparison of catalytic activities shows that the NiMo catalysts supported on Zr-SBA-15 exhibited a higher hydrotreating activity compared to γ-Al2O3and SBA-15 supported catalysts. [ABSTRACT FROM AUTHOR]

Introduction The burden of non-communicable diseases (NCDs) is fast changing across the world, especially in the context of rapid urbanization, adoption of Western lifestyles, and an aging multi-morbid population. Over the last three decades, India has undergone a significant demographic and socioeconomic transition. For effective targeting of health system resources and services, it is essential to understand how the prevalence of NCDs varies among population groups across India. We set out to understand the distribution of NCDs and co-morbidities in urban and rural West Bengal. Methods As part of a service improvement project, data was collected from four urban and four rural community-based clinics across West Bengal, India. The reason for visiting the healthcare center was recorded as the primary diagnosis and co-morbidities were recorded per the Elixhauser comorbidity scoring criteria. Associations between all the demographic variables and NCDs were studied using the Poisson regression model and multivariate analysis. Demographic profile, co-morbidities, and Elixhauser comorbidity index were expressed as frequency (%), mean (standard deviation, SD), or median (interquartile range, IQR) as appropriate. Results We obtained data from 1244 patients of which 886 (71%) were from urban areas and 358 (29%) were from rural areas. Patients were mostly female (61%) and had a mean (SD) age of 53 (11) years. There was a positive correlation between living in an urban residence and age, body mass index (BMI), hypertension, cardiovascular disease (CVD), and respiratory disease. There was a positive correlation between CVD and age, male sex, living in an urban residence, and hypertension but did not correlate positively with diabetes. BMI positively correlated with living in an urban residence, hypertension, diabetes, and musculoskeletal disorders. We observed a significantly higher prevalence of musculoskeletal (p=0.002) and psychological diseases (p<0.001) in the rural population, while the prevalence of hypertension (p<0.001) and respiratory diseases among the participants living in urban areas was higher (p<0.001). There was no statistically significant difference in the prevalence of diabetes between urban and rural areas (p=0.38). In the multivariable analyses, we observed that increased age, being overweight, and living in urban areas were associated with hypertension (prevalence ratio (PR): 1.40, 1.30, and 1.30, respectively; all p-values <0.05). An interaction between sex and living area was associated with a lower prevalence of musculoskeletal diseases (PR: 0.34; 95%CI: 0.18-0.66), i.e., musculoskeletal diseases were less prevalent in males living in urban areas (p=0.002). Conclusion There is a rise in multimorbidity with changing demographic patterns and a narrowing of the urban-rural gap in disease distribution. More investment is required in risk factor prevention, screening, and treatment, with greater accessibility of healthcare resources for those in rural areas. Further work needs to be done to study the trends and distribution of NCDs in West Bengal to inform healthcare policy., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Mukherjee et al.)