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Given the enormous and rising global need for permanent magnet supply, even minor enhancements to the magnetic characteristics and economic viability of permanent magnet materials could result in significant energy and financial savings. In this work, the experimental conditions were optimized in order to produce barium hexaferrite (BaFe12O19) substituted with transition elements (Co and Mn) through chemical co-precipitation method. Powder X-ray Diffraction (XRD), Transmission Electron Microscope (TEM) and Fourier Transform Infra-red (FTIR) were used to reveal the structure, morphology and vibrational spectrum of the sample. The site preference for cobalt and manganese was estimated using Rietveld refinement of the XRD spectrum. It is obvious that Co and Mn occupied two crystallographic inequivalent sites, 4f2 and 4f1 respectively. Investigation of magnetic properties (VSM) at room temperature showed that as Co and Mn concentrations increase, saturation magnetization and retentivity increase, but coercivity decreases. At higher substitution concentrations, the behavior is the inverse. The possible reasons for these behaviors were discussed. The close correlation between site selection by the dopant and magnetic properties is also demonstrated. [ABSTRACT FROM AUTHOR]

Annealing of a magnetic nanostructure is expected to not only change morphological features but also magnetic properties and hence magnetic hyperthermia applications. Using a simple co-precipitation method, annealed and non-annealed MWCNT/CoFe2O4 nanocomposites have been synthesized, as confirmed by phases depicted in XRD. Here, a comparative study of morphological features, magnetic properties and heat dissipation capability of as-synthesized samples has been done. Transmission electron microscopy and scanning electron microscopy images reveal the agglomerated nature of the nanostructure. A visible shift in peak position of FTIR spectroscopy and Raman shift for annealed MWCNT/CoFe2O4 nanocomposites from that of non-annealed MWCNT/CoFe2O4 nanocomposites implies change in the vibrational features. As evident from vibrating sample magnetometer, coercivity and saturation magnetization increases for annealed MWCNT/CoFe2O4 nanocomposites, heat dissipation capability quantified by the specific absorption rate and intrinsic loss parameter is also found to be amplified. [ABSTRACT FROM AUTHOR]

The synthesis of composite magnetic nanomaterials has received increasing attention due to their electronic, magnetic, catalytic, and chemical or biological sensing properties. We have prepared cobalt ferrite-zinc sulfide nanocomposites by a chemical route. The synthesized nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and photoluminescence spectrometer (PL). The fluorescent magnetic nanoparticles (FMNPs) had a typical diameter of 30±5 nm and saturation magnetization of 5.8 emu g-1 at room temperature. So, these FMNPs may be potentially applied in different fields such as optoelectronic devices, biolabeling, imaging, drug targeting, bioseparation, magnetic fluid hyperthermia, etc. [ABSTRACT FROM AUTHOR]

Background and Aims: Covid-19 virus started from Wuhan, China and has brought the world down to its knees. It has catapulted as a venomous global phenomenon. This study focuses on the Covid-19 situation in India and its recovery time., Method: The study period is from March 1, 2020 to April 25, 2020. A random sample of 221 individuals found positive with Covid-19 from March 1, 2020 to 31st March is included in the study which is followed up April 25, 2020. There is a male preponderance in the sample with 66% of the Covid-19 patients being male and about 34% being female. Kaplan-Meier Product limit estimator, Kaplan-Meier survival curve and Log-rank test are used to analyze the recovery time of Covid-19 patients., Result: From the results of the study, it is found that the average recovery time of Covid-19 patients in India is 25 days (95% C.I. 16 days to 34 days). Only 4% of the patients get cured after 10 days of treatment. The recovery time of male and female patients is not statistically different. Recovery time of patients belonging to different age groups is also not statistically significant., Conclusion: This information on recovery time of Covid-19 patients will help planners to chalk out effective strategies., Competing Interests: Declaration of competing interest The authors declare that there is no known competing interest, which could have influence in this paper., (Copyright © 2020 Diabetes India. Published by Elsevier Ltd. All rights reserved.)

Chlorophenols, typically 4-chlorophenols are highly toxic and non-biodegradable organic contaminants which pose serious threat to the environment, particularly when released into aqueous medium. The removal of these pollutants by efficient method has received worldwide concern in recent past. A new Fe 3 O 4 -Cr 2 O 3 magnetic nanocomposite was synthesized by wet chemical method under ultrasonic irradiation. Microstructure and morphology of the nanocomposite were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and a transmission electron microscope (TEM). Magnetic and optical properties were studied by a vibrating sample magnetometer (VSM) and an ultraviolet-visible (UV-Vis) spectrophotometer respectively. The magnetic nanocomposite (MNC) was used as photocatalyst for effective decomposition of 4-chlorophenol in water under ultraviolet (UV) irradiation., (Copyright © 2015. Published by Elsevier B.V.)

A combined sonochemical co-precipitaion method has been developed for the synthesis of a CoFe(2)O(4)-Cr(2)O(3)-SiO(2) magnetic nanocomposite. The synthesis involved the pre-synthesis of CoFe(2)O(4)-Cr(2)O(3) nanoparticles, which were subsequently coated with SiO(2) by treatment with tetraethyl orthosilicate. It was observed that the as-prepared CoFe(2)O(4)-Cr(2)O(3)-SiO(2) nanocomposite exhibits photoluminescence properties without the addition of any external fluorescent marker. The fluorescent magnetic nanoparticles (FMNPs) had a typical diameter of 30 ± 5 nm and a saturation magnetization of 5.1 emu g(-1) at room temperature. This as-prepared nanocomposite was used for staining cultured HeLa cells for fluorescence imaging.