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It is of interest to document the known data on CoVid-19 infection linked to type-2 diabetes. Hyperglycemia, inhibition of neutrophil chemotaxis, altered cytokine synthesis, phagocytic cell dysfunction, impaired T cell-mediated immune responses, and inadequate microbia were all seen in people with Diabetes. Individuals with diabetes have also been shown to elevate levels of the proinflammatory cytokine, especially IL-1, IL-6, and tumor necrosis factor-alpha (TNF-alpha), and different markers such as C reactive protein, D-dimer, and fibrinogen. This will prolong the cytokine storms and lead to severe illness in diabetic individuals with COVID- 19 infection. The role of acute glycemic control after COVID- 19 manifestation on clinical outcomes has not been known in detail. Known data shows that hyperglycemia facilitates local viral replication in the lungs and impairs anti-viral immune response. Thus, acute glycemic management plays an important role in limiting viral replication and disease progression in patients with diabetes. The available evidence implicates diabetes as important risk factors impacting the clinical severity of SARS-CoV-2.

Imidazole and coumarin are most widely used heterocyclic scaffolds which are used in synthesis of drug molecules. A series of 7-subsitituted coumarins have been synthesized by route of substitution and condensation reactions of 1 mol of 2,3-dibromodihydrocoumarines and 2 mol of urea and thiourea in ethanol as a solvent. The reactions were carried out thermally as well as by irradiation with microwave. Structure elucidation of these newly designed compounds have been confirmed by basis of IR, 1H NMR, 13C NMR, Mass spectral datas. This novel method involved simple experimental procedure, short time and excellent yield.

Janus kinase 2 (JAK2) is a tyrosine kinase receptor that belongs to the JAK family kinases is linked to oral cancer. We describe the molecular binding analysis of JAK2 with 23 compounds from tomotoes. Docking data shows five compounds (rutin, qucertin, narigenin, chlrogenia acid & kaempferol) with optimal binding features with JAK2 for further consideration.

Piperine is a component of Piper nigrum (Black pepper). It is well known in ayurvedic formulations. Piperine is a bioenhancer as it reduces the activity of drug-metabolizing enzymes in rodents and thereby enhancing the plasma concentrations of several drugs, including the Pglycoprotein substrates. Therefore, it is of interest to understand the molecular docking interactions of piperine with several cell cycle proteins such as Cyclin dependent kinase 2 (CDK2), Cyclin-dependent kinase 4 (CDK4), Cyclin D and Cyclin T for further consideration in drug discovery related to oral cancer.

There has been growing interest for the therapeutic use of traditional herbs in the management of diabetes mellitus (DM) and its complications. Data shows the hypoglycemic activity of

Cobalt and manganese-substituted zinc ferrite X0.4Zn0.6Fe2O4 (X = Co, Mn) nanoparticles have been synthesized by co-precipitation method and characterized for structural, morphology, and magnetic properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM). The Rietveld refinement method is employed to refine the XRD powder data, and the structural parameters are calculated from the refinement. Substitution of cobalt and manganese causes the lattice parameter to decrease. Particle size, measured from XRD, lies in the nanometer regime. A low saturation magnetization value is obtained in both samples, and the presence of non-collinear spin arrangement is found at octahedral sites. The maximum entropy method (MEM) is employed to study the strength of the bond between the atoms at tetrahedral and octahedral sites in the unit cell of ferrites. Optical band gap energy of the samples is determined by using UV–VIS techniques.

The partial substitution of Fe3+ by Cr3+ in strontium hexaferrite has shown to be an effective method to tailor anisotropy for many novel microwave applications. Some basic studies have revealed that this substitution leads to unusual interactions among the magnetic sublattices of the hexaferrite. In order to investigate these interactions, Cr3+ doped SrCrxFe12−xO19 (x=0.0, 0.1, 0.3, 0.5, 0.7 and 0.9) (m-type) hexaferrites were prepared by microwave-hydrothermal (m-H) method and subsequently sintered at 950 °C/90 min using microwave furnace. The magnetic hysteresis (m-H) loops revealed the ferromagnetic nature of nanoparticles (NPs). The coercive field was increasing from 3291 Oe to 7335 Oe with increasing chromium content. This resulting compacts exhibited high squareness ratio (Mr/Ms–80%). The intrinsic coercivity (Hci) above 1,20,000 Oe and high values of magnetocrystalline anisotropy revealed that all samples are magnetically hard materials. A material with high loss as well as high dielectric constant may be desired in applications such as electromagnetic (EM) wave absorbing coatings. The room temperature complex dielectric and magnetic properties (e′, e′′, µ′ and µ′′) of Cr3+ doped SrFe12O19 were measured in X-band region. The frequency dependent dielectric and magnetic losses were increasing to large extent. The reflection coefficient varied from −16 to −33 dB at 10.1 GHz as Cr3+ concentration increased from x=0.0 to x=0.9. Ferromagnetic resonance spectra (FMR) were measured in the X-band (9.4 GHz), linewidth decreases with chromium concentration from 1368 to 752 Oe from x=0.0 to x=0.9, which is quite low compared to commercial samples. We also have detailed origins of the FMR linewidth broadenings in terms of some important theoretical models. These results show that chromium doped strontium hexaferrites are useful for microwave absorption in the X-band frequency and also have potential for use in low frequency self-biased microwave/millimeter devices such as circulators and isolators.

Sc 3+ doped Mn 0.5 Zn 0.5 Sc y Fe 2−y O 4 (y=0.00, 0.01, 0.03 and 0.05) nanoparticles were synthesized by solution combustion method using mixture of fuels were reported for the first time. The mixture of fuels plays an important role in obtaining nano crystalline, single phase present without any heat treatment. X-ray diffraction (XRD) results confirm the formation of the single-phase ferrites which crystallize in cubic spinel structure. The Fourier transform infrared spectra (FTIR) exhibit two prominent bands around 360 cm −1 and 540 cm −1 which are characteristic feature of spinel ferrite. The transmission electron microscope (TEM) micrographs revealed the nanoparticles to be nearly spherical in shape and of fairly uniform size. The room temperature impedance spectra (IS) and vibrating sample magnetometry (VSM) measurements were carried out in order to study the effect of doping (Sc 3+ ) on the characteristic properties of Mn-Zn ferrites. Further, the frequency dependent dielectric constant and dielectric loss were found to decrease with increasing multiple Sc 3+ concentration. Nyquist plot in the complex impedance spectra suggest the existence of multiple electrical responses. Magnetic measurements reveals that saturation magnetization (M s ), remnant magnetization (M r ), magnetic moment (η B ) and magnetic particle size (D m ) increase with Sc 3+ ion concentration up to x=0.03 and then decrease. The values of spin canting angle (α Y-K ) and the magnetic particle size (D m ) are found to be in the range of 68–75° and 10–19 nm respectively with Sc 3+ concentration. The room temperature Mossbauer spectra were fitted with two sextets corresponding to ions at tetrahedral (A-) and octahedral (B-) sites confirms the spinel lattice. The ferromagnetic resonance (FMR) spectra's has shown that high concentration of scandium doping leads to an increase in dipolar interaction and decrease in super exchange interaction.

Ni 0.4 Zn 0.2 Mn 0.4 Fe 2 O 4 nanopowders were prepared by sol-gel auto-combustion method, densified at different temperatures 400–700 °C/4 h using conventional sintering method. The grain sizes of all the samples vary between 18 nm and 30 nm. The hysteresis loops show high saturation magnetization and low coercivity, indicating magnetically soft behaviour of the material. The real and imaginary parts of permittivity is almost constant upto 1 GHz and increases with further increase of frequency. The permeability is ruled by Snoek’s law, the values of μ′ increases with increase of temperature and the resonance frequency increases with an increase of temperature. The reflection coefficient is however increasing with sintering temperature and the maximum loss is observed in the range of 100 MHz–1 GHz. Sample sintered at 700 °C has shown maximum reflection loss and this loss occurs due to absorption, destructive interference and multiple internal reflections in the sample. Quality factor is constant upto 380 MHz and increases with frequency for all the samples sintered at different temperatures. The T C for all the samples is above ~230 °C. The room temperature EPR spectra confirm the oxidation state of Fe 3+ . The g -factor is in the range of ~2.

Bond strength values, between tetrahedral sites and octahedral sites atoms in the unit cell, are evaluated using maximum entropy method (MEM) for the Ni 0.8 Zn 0.2 Fe 2 O 4 nano ferrite particles, prepared by co-precipitation method and sintered at 900 °C. The spinel structure is confirmed from the XRD analysis done using the Rietveld method. Substitution of zinc ion causes increase in lattice parameter value. Thermal behavior, morphology, magnetic properties and optical band gap energy values of the sample are determined by using thermogravimetric analysis and differential thermal analysis, scanning electron microscope, vibrating sample magnetometer and UV–VIS–NIR techniques respectively. Low value of saturation magnetization is attributed to the disorder in cation distribution.

Nowadays electronic industries prerequisites magnetic materials, i.e., iron rich materials and their magnetic alloys. However, with the advent of high frequency applications, the standard techniques of reducing eddy current losses, using iron cores, were no longer efficient or cost effective. Current market trends of the switched mode power supplies industries required even low energy losses in power conversion with maintenance of adequate initial permeability. From the above point of view, in the present study we aimed at the production of Manganese–Zinc ferrites prepared via solution combustion method using mixture of fuels and achieved low loss, high saturation magnetization, high permeability, and high magnetic domain relaxation frequency. The as-synthesized Zn2+ substituted MnFe2O4 were characterized by X-ray diffractometer (XRD) and transmission electron microscopy (TEM). The fractions of Mn2+, Zn2+ and Fe2+ cations occupying tetrahedral sites along with Fe occupying octahedral sites within the unit cell of all ferrite samples were estimated by Raman scattering spectroscopy. The magnetic domain relaxation was investigated by inductance spectroscopy (IS) and the observed magnetic domain relaxation frequency (fr) was increased with the increase in grain size. The real and imaginary part of permeability (μ′ and μ″) increased with frequency and showed a maximum above 100 MHz. This can be explained on the basis of spin rotation and domain wall motion. The saturation magnetization (Ms), remnant magnetization (Mr) and magneton number (µB) decreased gradually with increasing Zn2+ concentration. The decrease in the saturation magnetization was discussed with Yafet–Kittel (Y–K) model. The Zn2+ concentration increases the relative number of ferric ions on the A sites, reduces the A–B interactions. The frequency dependent total power losses decreased as the zinc concentration increased. At 1 MHz, the total power loss (Pt) changed from 358 mW/cm3 for x=0–165 mW/cm3 for x=0.9. Pt for all the Zn doped samples exhibited the temperature stability up to 100 °C.

Al3Fe5O12 (AIG) nanopowders were synthesized at different pH using aqueous co-precipitation method. The effect of pH on the phase formation of AIG is characterized using XRD, TEM and TG/DTA. From Scherrer formula the average crystallite sizes were found to be 20, 25, 28 and 32 nm for pH 9, 10, 11 and 12. From TEM micrographs, the particle sizes of the powders were found to be 15, 21, 25 and 30 nm for pH 9, 10, 11 and 12, respectively. It is found that as the pH of the solution increase the particle size also increases. It is clear from the TG/DTA curves that as the pH is increasing the weight losses were found to be small. The obtained nanopowders were further sintered at 900 °C/4 h using conventional sintering method. The phase formation is completed at 800 °C which is correlated with TG/DTA. X-ray photoelectron spectroscopy is used to study the electronic state of the AIG sample. The average grain size of the samples is found to be ~55 nm. Room temperature magnetization measurements established these compounds to be soft magnetic. The room temperature dielectric and magnetic properties (e′, e″, µ′ and µ″) of AIG was studied over a wide range of frequency 1 MHz–1.8 GHz. The dielectric constant was found to decrease with increasing frequency. With increase of pH both e′ and µ′ increased. The Curie temperature was confirmed to be from 560 K (~287 °C) based on the dielectric anomaly observed when these measurements were carried out over a temperature range of 300–600 K. The ferromagnetic resonance linewidth is found to be increasing from 77 to 142 Oe and the effective saturation magnetization (4πMeff) is found to be higher compare to effective saturation magnetization (4πMs) by VSM. This finding provides a new route for AIG materials could be useful for various applications for spintronics.

Nanostructured xTiO 2 +(1-x) Ni 0.53 Cu 0.12 Zn 0.35 Fe 2 O 4 nanocomposites (where 0 ≤ x ≤ 1) were prepared by a low temperature microwave-hydrothermal (M-H) method at 165 °C/45 min. Microwave sintering (MS) technology has been applied in the preparation of nanocomposites. Several kinds of such systems have been fabricated by MS technology. The sintering time and temperature were reduced from 22 h to 1100 °C for conventional sintering process to 30 min and 500 °C for MS process, respectively. The addition of TiO 2 to Ni 0.53 Cu 0.12 Zn 0.35 ferrite increased the dielectric properties (e′ and e″). The imaginary part of permeability (μ″) was found to increase with an increase of TiO 2 . The complex permittivity and permeability were collected by the vector network analyser and the absorbing properties were calculated according to transmission theory. The absorption peak shifted to higher frequencies with the substitution. The highest reflection coefficient value of −28 dB at 10.26 GHz was observed for the x = 0.5 sample. The microwave absorption band width of −10 dB with xTiO 2 +(1-x) Ni 0.53 Cu 0.12 Zn 0.35 Fe 2 O 4 nanocomposites is effectively broadened compared with other ferrites. Based on the magnetic and microwave measurements xTiO 2 +(1-x) Ni 0.53 Cu 0.12 Zn 0.35 Fe 2 O 4 may be a good candidate for electromagnetic materials and other practical applications like military and civil applications.

Co1−xZnxFe2O4 (0 ≤ x ≥ 1) nanopowders were synthesized using microwave hydrothermal method. The synthesized powders were characterized by X-ray diffraction and transmission electron microscope (TEM). The average particle size was obtained from TEM and it is found to be 17 nm. Then powders were sintered using microwave sintering method at 900 °C/15 min. The real part of permittivity varies as Zn concentration increases and the resonance frequency was observed at much higher frequencies (>1 GHz) and there is a significant decrease in the loss factor. The dielectric parameters were observed to decrease with the increased Zn contents. The frequency dependent dielectric properties of all these nanomaterials have been explained qualitatively in accordance with Koop’s phenomenological theory. The magnetic permeability spectra exhibit resonance and anti-resonance type behaviour. Lower reduced remnant magnetization (Mr/Ms) values (x

The structural analysis and magnetic investigation Mn1−xZnxFe2O4 with stoichiometry (x=0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0) were synthesized by solution combustion method using mixture of fuel this is first of its kind. As synthesized Mn–Zn nanoferrites were characterized by X-ray Diffractometer (XRD), Transmission electron microscopy (TEM) at room temperature. The magnetic domain relaxation was investigated by inductance spectroscopy (IS) and the observed magnetic domain relaxation frequency (fr) was increased with the increase in grain size. The Room temperature magnetic properties were studied using vibrating sample magnetometer (VSM). It was observed that the real and imaginary part of permeability (μ′ and μ″), saturation magnetization (Ms), remanance magnetization (Mr) and magneton number (Mr/Ms) were decreases gradually with increasing Zn2+ concentration. The decrease in the saturation magnetization may be explained as, the Zn2+ concentration increases the relative number of ferric ions on the A sites diminishes and this reduces the A–B interaction. Hence synthesized materials are good for high frequency applications.

Solution combustion method was successfully used for the synthesis of nanocrystalline Mn1-xZnxFe2O4 with stoichiometry (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0). The room temperature dielectric studies real and imaginary part of permittivity (epsilon' and epsilon `') were undertaken in the vide frequency range 1 MHz to 1 GHz. It was found that the real part of permittivity (epsilon') is increases with increasing in frequency and it shows a resonance behavior above 1 GHz and at much higher frequencies there is a significant decrease in the loss factor (epsilon `'). The magnetic domain relaxation was investigated by inductance spectroscopy (IS) and the observed magnetic domine relaxation frequency (f(r)) was increased with increase of grain size. It was observed that the real and imaginary part of permeability (mu' and mu `'), saturation magnetization (M-s), remnant magnetization (M-r) and magneton number decreases gradually with increasing Zn2+ concentration. The decrease in the saturation magnetization may be explained as the Zn2+ concentration increases, the relative number of ferric ions on the A sites diminishes and this reduces the A-B interaction.

Nanocrystalline Mn0.4 Zn0.6SmxGdyFe2-(x+y)O4 where x and y = 0.01,0.02,0.03,0.04 and 0.05 were synthesized by Solution combustion method. The as prepared samples were characterized by X-ray diffractometer (XRD), Transmission electron microscopy (TEM) and Vibrating sample Magnetometer (VSM) at room temperature. From the XRD the crystallite size were found increases with the increase of Sm3+-Gd3+ ions concentration while lattice parameter found to decreases. The real and imaginary part of permittivity (e′ and e′′) were undertaken in the wide frequency range 1GHz to 5GHz at room temperature. It is found that the real and imaginary part of permittivity’s are increasing with increasing Sm3+ and Gd3+ concentration. The magnetic behaviour of as synthesized nano ferrites reveals that, the saturation magnetization (MS), remanence magnetization (MR) is increasing with increasing Sm and Gd concentration. The g-value, peak-to-peak linewidth and spin concentration evaluated from EPR spectra correlated with cations occupancy. These electromagnetic properties clearly indicates that the synthesized materials are the good candidates for L and C band frequency.

Nanocrystalline Mn0.4Zn0.6SmxGdyFe2-(x+y)O4 (x = y = 0.01, 0.02, 0.03, 0.04 and 0.05) were synthesized by combustion route. The detailed structural studies were carried out through X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM). The results confirms the formation of mixed spine phase with cubic structure due to the distortion created with co-dopants substitution at Fe site in Mn-Zn ferrite lattice. Further, the crystallite size increases with an increase of Sm3+-Gd3+ ions concentration while lattice parameter and lattice strain decreases. Furthermore, the effect of Sm-Gd co-doping in Mn-Zn ferrite on the room temperature electrical (dielectric studies) studies were carried out in the wide frequency range 1 GHz-5 GHz. The magnetic studies were carried out using vibrating sample magnetometer (VSM) under applied magnetic field of 1.5T and also room temperature electron paramagnetic resonance (EPR) spectra's were recorded. From the results of dielectric studies, it shows that the real and imaginary part of permittivities are increasing with variation of Gd3+ and Sm3+ concentration. The magnetic studies reveal the decrease of remnant, saturation magnetization and coercivity with increasing of Sm3+-Gd3+ ion concentration. The g-value, peak-to-peak line width and spin concentration evaluated from EPR spectra correlated with cations occupancy. The electromagnetic properties clearly indicate that these materials are the good candidates which are useful at L and C band frequency. (C) 2015 Elsevier B.V. All rights reserved.

Nanocrystalline Co1−xZnxFe2O4 (0≤x≥1) powders were synthesized using the microwave hydrothermal method at different synthesis conditions. The synthesized powders were characterized by XRD and TEM. The average particle size was obtained from TEM and it is found to be 17 nm. Then the powders were sintered using the microwave sintering method at 900 °C/15 min. A detailed study of elastic behavior of Co0.4Zn0.6Fe2O4 has been undertaken using a composite piezoelectric oscillator method over a temperature range of 300–600 K. The elastic modulus of all the ferrites was found to decrease with an increase in the temperature, except near the Curie temperature (TC), where a small anomaly is observed. The above observations were carried in the demagnetized state; the application of a 380 mT magnetic field allowed us to reach the saturated state of the sample at any one of the measuring temperatures. The anomaly observed in the thermal variation of elastic moduli is qualitatively explained with the help of temperature variation of magneto-crystalline anisotropy constant.

Nanocrystalline Mn1-xZnxFe2O4 (x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) ferrites have been successfully synthesised using microwave–hydrothermal method for high frequency applications. The nanopowders were characterised using X-ray diffraction (XRD) and sintered using microwave furnace at 900°C and the total time taken for sintering is 30 min. The frequency dependence of real and imaginary part of permeability were measured in the range 1 MHz to 1.8 GHz. The saturation magnetisation and coercive force were obtained using a vibration sample magnetometer (VSM) in the field of 1.5 T. The temperature dependence of initial permeability (μi) was measured in the temperature range of 300K to 600K at 10 kHz. The high values of permeability and saturation magnetization enables these materials to be the potential candidates for a number of applications, for example, in transformers, choke coils, noise filters and recording heads.

The Dy3+ doped Y3−xDyxFe5O12 (x=0–3) nanopowders were prepared using microwave hydrothermal route. The structural and morphological studies were analyzed using transmission electron microscope, X-ray diffractometer and field emission scanning electron microscope. The nanopowders were sintered at 900 °C/90 min using microwave furnace. Dense ceramics with theoretical density of around 95% was obtained. Ferro magnetic resonance (FMR) spectrum and microwave absorption spectrum of Dy3+ doped YIG were studied, the signal exhibits a resonance character for all Dy3+ variations. It was observed that the location of the FMR signal peak at the field axes monotonically shifts to higher field with increasing Dy3+ content. The dielectric and magnetic properties (e′, e′′, µ′ and µ′′) of Dy3+ doped YIG were studied over a wide range of frequency (1–50 GHz). With increase of Dy3+ both e′ and µ′ decreased. The low values of dielectric, magnetic properties and broad distribution of FMR line width of these ceramics are opening the real opportunity to use them for microwave devices above K- band frequency.

Ni0.4Zn0.2Mn0.4Fe2O4 nanopowders were prepared by auto-combustion method. The as-synthesized powders were characterized using X-ray diffraction (XRD) and thermo-gravimetric-differential thermal analysis (TG-DTA), and the powders were densified at different temperatures 400 degrees C, 500 degrees C, 600 degrees C and 700 degrees C/4 hrs using conventional sintering method. The sintered samples were characterized by XRD and transmission electron microscope (TEM). The bulk densities of the samples were increased with an increase of sintering temperature. The grain sizes of all the samples vary in between 18 nm to 30 nm. The hysteresis loops show high saturation magnetization and low coercivity, indicates that it is a soft material. The incremental permeability (permeability with magnetic field superposition) was influenced by both ΔM and H(c). A sample with higher initial permeability and favoured the attainment of a higher incremental permeability. The Q-factor was mainly determined by the sintered density and microstructure. To summarize, a uniform and dense microstructure with relatively small average grain size is favourable for obtaining better dc-bias-superposition characteristics, including permeability and Q-factor.

Nanocrystalline magnesium–copper–zinc (Mg0.30Cu0.20Zn0.50Fe2O4) ferrites were prepared by microwave sintering technique. The effects of the sintering temperature on particle size and magnetic properties were investigated. In this article, optimum sintering temperature required for MgCuZn ferrite system for obtaining good electromagnetic properties, suitable for applications in low temperature co-fired ceramics (LTCC) chip components was studied. The grain size, initial permeability, dielectric constant and saturation magnetisations were found to increase, and dielectric loss was found to decrease with the increasing sintering temperature. Mg–Cu–Zn ferrites with a permeability of μ = 1110 (at 1 MHz) were fully densified at the standard LTCC sintering temperature of 950°C.

The Sm3+ doped Y3−xSmxFe5O12 (x = 0–3) nanopowders were prepared using modified sol–gel route. The crystalline structure and morphology was confirmed by X-ray diffraction and atomic force microscopy. The nanopowders were sintered at 950 °C/90 min using microwave sintering method. The lattice parameters and density of the samples were increased with an increase of Sm3+ concentration. The room temperature dielectric (e′ and e″) and magnetic (μ′ and μ″) properties were measured in the frequency range up to 20 GHz. The room temperature magnetization studies were carried out using Vibrating sample magnetometer using filed of 1.5 T. Results of VSM show that the saturation and remnant magnetization of Y3−xSmxFe5O12 (0–3) decreases on increasing the Sm concentration (x). The low values of magnetic (μ′ and μ″) properties makes them a good candidates for microwave devices, which can be operated in the high frequency range.

Oral health is an integral component of general health and is essential for a person's comprehensive well being. The current outlook towards oral health has broadened beyond the concept of just good teeth and has evolved to encompass freedom from chronic pain, the absence of oral and throat carcinoma, oral sores and birth defects such as cleft lip and palate, freedom from periodontal diseases, tooth decay, tooth loss and many other diseases and disorders that affect the mouth and oral cavity.

The Y3Fe5O12 (YIG) nanopowders were synthesised at different pH using co-precipitation method. The effect of pH on the phase formation of YIG is characterised using XRD, TEM, FTIR and TG/DTA. From the Scherer formula, the particle sizes of the powders were found to be 13, 19 and 28 nm for pH = 10, 11 and 12 respectively. It is found that as the pH of the solution increase the particle size is also increases. It is also clear from the TG/DTA curves that as the pH is increasing the weight losses were found to be small. The nanopowders were sintered at 600, 700, 800 and 900°C for 5 h using conventional sintering method. The phase formation is completed at 800°C/5 h which is correlated with TG/DTA. The average grain size of the samples is found to be ∼161 nm. The high values of Ms = 23 emu g−1 and Hc = 22 Oe were recorded for the sample sintered at 900°C.

The nanocomposites of x TiO 2 +(1− x )Ni 0.53 Cu 0.12 Zn 0.35 Fe 2 O 4 (where 0≤ x ≥1) were prepared using microwave–hydrothermal (M–H) method at 165 °C/45 min. The as-synthesized powders were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The particle size of the powder varies from 18 to 35 nm. The as prepared powders were densified at 500 °C/30 min using microwave sintering method. The sintered composites were characterized by XRD and scanning electron microscopy (SEM). The bulk densities of the present composites were increasing with the addition of TiO 2 . The grain sizes of all the composite vary between 65 nm and 90 nm. The addition of TiO 2 to ferrite increased the dielectric properties ( e ′ and e ″) also the resonant frequency of all the composites was found to be greater than 1 GHz. The imaginary part of permeability ( μ ″) was found to increase with an increase of TiO 2 .

Nanocrystalline BaFe12O19 powders were prepared by microwave-hydrothermal method at 200 °C/45 min. The as-synthesized powders were characterized by using X-ray diffraction (XRD), thermogravimetry (TG) and differential thermal analysis (DTA). The present powders were densified at different temperatures, i.e., 750, 850, 900 and 950 °C for 1 h using microwave sintering method. The phase formation and morphology studies were carried out using XRD and field emission scanning electron microscopy (FE-SEM). The average grain sizes of the sintered samples were found to be in the range of 185–490 nm. The magnetic properties such as saturation magnetization and coercive field of sintered samples were calculated based on magnetization curves. A possible relation between the magnetic hysteresis curves and the microstructure of the sintered samples was investigated.

Microwave-hydrothermal (M-H) method has been successfully used for synthesis of nanocrystalline Mn–Zn ferrites which are used for high frequency applications. The nanopowders were characterized using XRD and TEM. The particle size of the samples varies from ∼20 nm to 25 nm. The powders were densified at 900 °C/30 min using microwave sintering method. The sintered ferrite samples were characterized using XRD, X-ray photoelectron spectroscopy (XPS), SEM and energy dispersive X-ray spectroscopy (EDS). The elastic behaviour and internal friction studies were carried out using composite piezoelectric oscillator method in the temperature range of 300–600 K. It was found that the anomalous behaviour observed in the temperature dependence of Young's modulus and internal friction disappears with the application of a magnetic field equal to the saturation field (900 mT) of the specimen under investigation. The observed anomalous behaviour in the vicinity of the Curie temperature was understood with the help of Landau's theory.

The nanocomposites of xTiO2 + (1 − x) CoFe2O4 (where 0 ≤ x ≥ 1) were prepared using microwave–hydrothermal method at 165 °C/45 min. The as-synthesized powders were characterized using X-ray diffraction (XRD), transmission electron microscope and Fourier transform infrared spectroscopy. The particle size was found to be ~18, ~22 and 24 nm for TiO2, CoFe2O4, 50 mol% TiO2 + 50 mol% CoFe2O4 composite powder, respectively. The as-prepared powders were densified at 500 °C/30 min using microwave sintering method. The sintered composite samples were characterized using XRD and field emission scanning electron microscopy. The bulk densities of the present composites were increasing with an addition of TiO2. The saturation magnetization of composites decreased with an increase of TiO2 content. The grain sizes of all the composite lies between 54 and 78 nm. The addition of TiO2 to ferrite increased e′ and e″ and the resonant frequency of all the sintered samples were found to be >1 GHz. The value of μ″ found to increase with an increase of TiO2.

The nanocrystalline MgCuZn ferrites with particle size (∼30 nm) have been synthesized by microwave–hydrothermal (M–H) method at 160 °C/45 min. The powders were densified at 750–900 °C/30 min using microwave sintering method. The sintered samples were characterized using X-ray diffraction and scanning electron microscope. The grain sizes of the sintered samples are in the range of 60–80 nm. The ultrasonic velocities have been measured on MgCuZn ferrites using the pulse transmission method at 1 MHz. The ultrasonic velocity is found to decrease with an increase of temperature. A small anomaly is observed around the Curie temperature, 520 K. The anomaly observed in the thermal variation of longitudinal velocity and attenuation is explained with the help of magneto-crystalline anisotropy constant.

Ni 0.53 Cu 0.12 Zn 0.35 Fe 2 O 4 /SiO 2 nanocomposites with different weight percentages of NiCuZn ferrite dispersed in silica matrix were prepared by microwave-hydrothermal method using tetraethylorthosilicate as a precursor of silica, and metal nitrates as precursors of NiCuZn ferrite. The structure and morphology of the composites were studied using X-ray diffraction and scanning electron microscopy. The structural changes in these samples were characterized using Fourier Transform Infrared Spectrometer in the range of 400–1500 cm −1 . The bands in the range of 580–880 cm −1 show a slight increase in intensity, which could be ascribed to the enhanced interactions between the NiCuZnFe 2 O 4 clusters and silica matrix. The effects of silica content and sintering temperature on the magnetic properties of Ni 0.53 Cu 0.12 Zn 0.35 Fe 2 O 4 /SiO 2 nanocomposites have been studied using electron spin resonance and vibrating sample magnetometer.

To investigate the modification effect of the modifier ZnO on boro-tellurite glass, a series of glasses with compositions 50B 2 O 3 –(50− x )ZnO– x TeO 2 have been prepared by conventional melt quenching technique. Amorphous nature of the samples was confirmed through X-ray diffraction technique. Optical absorption and IR structural studies are carried out on the glass system. The optical absorption studies revealed that the cutoff wavelength increases while optical band gap ( E opt ) and Urbach energy decreases with an increase of ZnO content. Refractive index evaluated from E opt was found to increase with an increase of ZnO content. The compositional dependence of different physical parameters such as density, molar volume, oxygen packing density, optical basicity, have been analyzed and discussed. The IR studies showed that the structure of glass consists of TeO 4 , TeO 3 /TeO 3+1 , BO 3 , BO 4 and ZnO 4 units.

The synthetic zeolites of the heulandite group were prepared using the microwave hydrothermal method at 120°C for 30 min. The powders were characterised using X‐ray diffraction. The zeolites were annealed at 60, 80 and 100°C for 1 h. Dehydration studies were conducted on prepared zelolite in the temperature range 300–800 K using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). A conventional ultrasonic pulse transmission technique was used to measure the longitudinal ultrasonic velocity and attenuation at 1 MHz in the temperature range 300–500 K. The accuracy of ultrasonic velocities and attenuation measurements was 0·01 and 0·2% respectively. The observed ultrasonic velocity changes were compared with FTIR, DSC and TGA studies, and it was found that the one can study dehydration studies in zeolites by carrying out ultrasonic studies.

The nanocrystalline Ni 0.53 Cu 0.12 Zn 0.35 Fe 1.88 O 4 and BaTiO 3 powders were prepared using Microwave–Hydrothermal ( M – H ) method at 160 °C/45 min. The as synthesized powders were characterized using the X-ray diffraction (XRD) and Transmission Electron Microscope (TEM). The size of the powders that were synthesized using M – H system was found to be ∼30 and ∼50 nm for ferrite phase and ferroelectric phases, respectively. The powders were densified using microwave sintering method at 900 °C/30 min. The ferrite and ferroelectric phases were observed from XRD and morphology of the composites was observed with the Scanning Electron Microscope (SEM).The magnetic hysteresis loops were recorded using the Vibrating Sample Magnetometer (VSM).The frequency dependence of real ( μ ′) and imaginary ( μ ″) parts of permeability was measured in the range of 1 MHz–1.8 GHz. The permeability decreases with an increase of BaTiO 3 content at 1 MHz. The transition temperature ( T C ) of ferrite was found to be 245 °C. The T C of composite materials decreases with an increase in BaTiO 3 content.

The nanocomposites of NiCuZnFe2O4-SiO2 were prepared using Microwave-Hydrothermal method at 160°C/45 min.The as-synthesized powders were characterized using X-ray diffraction and Transmission Electron Microscope (TEM).The average particle size of the powders were found to be ∼20 nm.The powders were densified at 900°C/30 min using Microwave sintering method. The sintered composite samples were characterized using XRD and Scanning Electron Microscopy (SEM). Crystallite size of the ferrites decreases with an increase of SiO2 content. The density of the composites varies of 93–98% of theoretical density. The densities of the present composites were increasing with the addition of SiO2. The bulk densities of the present composites were increasing with the addition of SiO2. The structural changes in these samples were characterized using Fourier Transform Infrared Spectrometer (FTIR) in the 400–4000 cm−1. The bands in the range of 580–880 cm−1 show a slight increase in intensity, which could be ascribed to the ...

Gliomas are one of the most prevalent and aggressive form of brain tumours in the world. Patient's usually go on to live a very short life after the initial diagnosis. Therefore, it is crucial to successfully and quickly outline a method for diagnosing the same in it's very earliest stages.Magnetic Resonance Imaging, or MRI as it is more frequently called is a noninvasive method of imaging parts of human anatomy. MRI's utilise robust fields of magnetism, along with waves that have frequencies corresponding to the radio waves in the spectrum to develop precise pictures to get a sense of the happenings inside the human body. The current, most widely used method of diagnosis for brain gliomas involves an oncologist or radiologist reading the MRI image and using his knowledge and experience regarding the same to reach a diagnosis. However, this manual method of diagnosis is very tedious and has been prone to errors in the past. Therefore, it essential to develop an automatic method for the same.Most of the techniques used currently for segmenting brain tumours were initially developed for other diseases, the most common use among them being the separation of white matter lesions. Most of the current methodologies can be broadly categorised into two families- 1.General Probabilistic Methods- Probabilistic methods are a remarkable method to establish the validity of combinatorial entities with distinct characteristics. Although the basis of their existence lies in probability, they are not bounded by it and can be used to solve and evaluate theorems across different branches of Mathematics.2.Discriminative Approaches- They are also sometimes referred to as Conditional Models. We utilise CNN's for faster and accurate processing of the data.

A laser ablation method was used for the preparation of nanocrystalline Mn–Zn ferrite thin films. Films were characterized using X-rays and TEM. The magnetic properties were measured using the vibrating sample magnetometer (VSM). The elastic behaviour and internal friction studies were carried out using composite piezoelectric oscillator method in the temperature range of 300–600 K. It was found that the value of Young's modulus decreases with an increase of temperature and shows anomalous behaviour in the vicinity of the Curie temperature. The internal friction for the present ferrites increases continuously with temperature up to the Curie point and a narrow peak was observed just below the Curie temperature. It was found that the anomalous behaviour observed in the temperature dependence of Young's modulus and internal friction disappears with the application of a magnetic field equal to the saturation field (900 mT) of the specimen under investigation. The observed anomalous behaviour in the vicinity of the Curie temperature was understood with the help of Landau's theory.

Nanocrystalline Mn–Zn ferrites have been successfully synthesised using the microwave–hydrothermal method for high frequency applications. The nanopowders were characterised using X-ray diffraction (XRD) and transmission electron microscopy (TEM). They were annealed using the microwave sintering method at 900°C for 20 min. The frequency dependence of the dielectric constant ϵ′ and and the initial permeability μ i were measured in the range 10 Hz to 1·3 GHz. The saturation magnetisation M s and coercive force H c were obtained using a vibration sample magnetometer (VSM) in the field of 20 kOe. The total power loss was measured in the range of 100 kHz to 1 MHz with a flux density of 50 mT on the annealed samples. Conductor-embedded ferrite transformers were fabricated and the output power P o and efficiency η were measured; 80% efficiency was obtained for a forward-type multilayered transformer.

The microwave–hydrothermal method has been successfully used for synthesis of nanocrystalline Mn–Zn ferrites which are used for high frequency applications. The nanopowders were characterised using X-ray diffraction and TEM. The nanopowders were annealed using microwaves at 600°C/10 min. The frequency dependence of dielectric constant ϵ′ was measured in the range from 10 Hz to 1·3 GHz, and initial permeability μ i was measured in the range from 10 Hz to 1 MHz. The total power loss was measured at 100 kHz and 200 mT on the annealed samples. Conductor embedded ferrite transformers were fabricated, and output power P o, efficiency η and temperature increase ΔT were measured at sinusoidal voltage of 25 V with frequency 1 MHz. The transformer efficiency η was found to be high, and surface rise of temperature ΔT is very low.