Vibrating Sample Magnetometer Research Articles

Preparation and Evaluation of Polyethylene Glycol Conjugated Polyethylene Imine‐Coated Magnetic Nanoparticles for Paclitaxel Delivery to Cervical Cancer Cells

ABSTRACTThe purpose of this study was to synthesize and characterize the therapeutic effect of paclitaxel‐loaded polyethylene glycol modified polyethylene imine‐coated iron oxide nanoparticles on cervical cancer cell line (HeLa cell). The physiochemical characteristics of nanocarriers were confirmed by using several methods including X‐ray diffraction (XRD), Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT‐IR), Vibrating sample magnetometer (VSM), Dynamic light scattering (DLS), and Transmission electron microscopy (TEM). The results showed the magnetic nanoparticles with size of 35 nm and excellent magnetic properties could load paclitaxel with capacity (16%) and encapsulation efficiency (80%) that has revealed pH‐dependent release behavior. The anticancer effects of nanoparticles were investigated using MTT assay. In comparison to free drug, paclitaxel‐loaded magnetic nanocarrier revealed more cytotoxicity against HeLa cell line and also resulted in an increased rate of apoptotic cancer cells, assessed by flow cytometry analysis. Furthermore, the developed magnetic nanocarrier showed suitable hemocompatibility which can be used in clinical applications.

Optimization of Magnetite Nanoparticles for Magnetic Hyperthermia: Correlation with Physicochemical Properties and Cation Distribution

AbstractThe present study reveals the synthesis of Iron oxide nanoparticles (IONPs) by varying the molar ratio of ferric (Fe3+) to ferrous (Fe2+) ions via chemical coprecipitation method for the study of cationic distribution of Fe‐ions and its potential application for magnetic hyperthermia therapy (MHT). X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X‐ray photoelectron spectroscopy (XPS), were used to characterize the physicochemical properties. Several structural parameters were estimated using the Rietveld refinement, resulting in structural modelling verified by magnetic characteristics. A vibrating sample magnetometer (VSM) assessed the magnetic hysteresis loop at room temperature in a field range of ±15 kOe, revealing superparamagnetic behavior for the ratio Fe2+/Fe3+ 1:2. The saturation magnetization (Ms) of IONPs increased with the increasing Fe2+ concentration and attained a maximum value of 60.21 emu g−1 at a molar ratio of 2:1. The potential of the inductive heating capability of IONPs in an alternating current magnetic field (AMF) was studied to treat localized MHT. The changes in magnetic properties and inductive heating properties of IONPs are associated with the cationic distribution of Fe2+ at the tetrahedral (A) and octahedral (B) sites of crystal structure. The variation in cationic properties at the A and B sites may result in varying/tuneable magnetic properties, affecting the overall heating profiles of hyperthermia.

Impact of Al3+ substitution in M-type hexaferrite on structural, magnetic, and dielectric properties

Hexaferrites SrAlxFe12−xO19 (x = 0, 1, 2, 3, and 4) doped by Al3+ in an account of Fe3+ were synthesized using microwave digestion. X-ray diffraction pattern analysis revealed that the compound is polycrystalline with a hexagonal M-type structure of SrAlxFe12−xO19 and P63/mmc space group is predominant for all dopants of Al3+ ion. The crystallite size of the SrAlxFe12−xO19 phase has a maximum value for the un-doped sample (94.5 nm) and then decreases for all values of Al-doping. The SEM results showed that the average grain size increased with Al-doping till x = 2 and was almost stable. The magnetic properties were investigated by vibrating sample magnetometer. The results showed a continuous decrease in both saturation (Ms), and remnant (Mr), magnetization with Al-doping. At the same time, the coercive magnetic field, Hc, increases continuously with Al-doping except for x = 4, Hc slightly decreased. These results make these compound candidates to be used in data storage and magnetic memories. Dielectric properties investigation showed low-frequency dispersion in the dielectric results due to a space-charge effect. It has been demonstrated that enhancements in conductivity, dielectric constant (ε′), and dielectric loss (ε′′) rise with an increase in the concentration of Al3+ ions, suggesting that SrAlxFe12−xO19 can be used for microwave absorption and other high-frequency applications.

Analysis of structural, mechanical, and magnetic properties of electroplated NiAg thin films synthesized at different deposition time

By changing the electroplating deposition duration, such as 15, 30, 45, and 60 minutes, the NiAg thin films have been synthesised by electrodeposition on copper substrate at a uniform current density of 1 A/dm2 . The NiAg thin films were adhered to the substrate at a consistent electrolytic solution temperature of 30°C, and the created electrolyte's pH was maintained within a range of 7 to 8. EDAX, XRD, and SEM techniques have all been used to investigate the structural investigation of electrodeposited NiAg thin films. The FCC crystal structure can be seen by the X-ray diffraction analysis pattern, which indicates that the average crystalline size of the NiAg-coated thin films was between 31 and 64 nm.Images of coated thin films taken with a scanning electron microscope show that, even with longer deposition times, the surface morphology of electrodeposited NiAg thin films is consistent. The Vibrating Sample Magnetometer (VSM) examination was used to investigate the magnetic characteristics. With a greater saturation magnetization of 7.6930 × E-3 emu/cm3 and a lower coercivity of 92 Oe, the NiAg film deposited at 15 minutes shows a better soft magnetic nature. According to the electrochemical analyses of plated NiAg thin films, the NiAg film coated at the 60 -minute deposition period showed the lowest corrosion rate, measuring 0.047286 mm/year with a polarization resistance of 3900.9 Ω. NiAg thin films' mechanical and magnetic characteristics make them suitable to produce MEMS and NEMS based devices.

Diamagnetic to Ferromagnetic Like Transition of Non-Stoichiometry Barium Titanate (BaTiO3-x) Prepared by Sol-gel Method

The oxygen vacancy properties are significant, creating ferromagnetic properties of material in metal oxide systems like dilute magnetic semiconductors. An aqueous sol-gel method has been used in the present study to synthesize non-stoichiometry BaTiO3-x polycrystalline. In an attempt of examining the oxygen deficiency consequences on the magnetic properties, the gel samples were sintered (1000◦C) at various times (6, 12, 18, and 24 hours) under a vacuum environment. This study employs an X-ray diffraction apparatus in terms of characterizing segments and structures of the samples. It also investigates morphology and element distribution on the surface of the samples exploiting an Electron microscope where Energy dispersive spectroscopy is supplied. For the purpose of characterizing the magnetic properties of the samples, it applies vibrating sample magnetometers. The chemical state of the element and its corresponding bond to other elements was identified using X-ray photoelectron spectroscopy. Single-phase compounds were observed. The crystal system is tetragonal, but the crystal parameters are different. Increase sintering time leads to increase crystallite size and decrease in micro strain. Moreover, sintering in a vacuum environment results in oxygen deficiency and leads to the atomic ratio of Ba/Ti change as the sintering time increases. The Ba/Ti ratio change affects the transformation from diamagnetic to ferromagnetic-like. The elements (Ba, Ti and O) chemical state is shown and its bonding to the corresponding element along with the X-ray photoelectron spectroscopy pattern of the BTX2 sample. The element of oxygen binds to Ti and Ba while Ba element exists in two chemical states.

Collective effect of reduced graphene oxide and Zn2U hexaferrite filler based epoxy composites on microwave absorption with improved mechanical properties

Herein, we have synthesized Ba4Zn2Fe36O60 (Zn2U) and have produced reduced graphene oxide (rGO) wrapped filler material for the preparation of epoxy composites of different weight percentages (40, 50 and 60 wt %). These rGO wrapped Zn2U hexaferrite filler was analyzed by XRD and SEM to examine the crystal structure and distribution of Zn2U hexaferrite in between/on the surface of rGO respectively. The magnetic and mechanical properties of prepared rGO@Zn2U@epoxy composites were evaluated by employing vibrating sample magnetometer and universal testing machine respectively. The investigation involved analyzing the complex permittivity and permeability, and based on this information, an assessment of the reflection loss was conducted. The results obtained indicate that epoxy composites with a filler content of 60 % rGO@Zn2U have significant promise as an advantageous choice for EMI shielding and microwave absorption applications.

Synthesis of Copper-Doped Metal Nanoferrites for Efficient Removal of Pharmaceutical Wastewater Pollutants in Membrane Bioreactor System

Pharmaceuticals present in the aquatic environment can poison aquatic species and humans through drinking water and cause harmful bacteria to become resistant. The role of transition metal doped metal nanoferrites for the enhanced efficiency of degradation process is widely achieved. In this work, copper doped magnesium ferrite (Cu-MgFe2O4) and copper doped zinc ferrite (Cu-ZnFe2O4) nanoparticles were synthesized using a sol-gel method. X-ray diffraction (XRD) analysis confirmed the formation of the spinel structure for both samples, with crystal sizes of 16.72 nm and 59.05 nm, respectively. The magnetic properties of the samples were studied using a vibrating sample magnetometer (VSM), which revealed that the addition of Cu2+ ions has a significant impact on the magnetic properties of the nanoparticles. The saturation magnetisation (Ms), retentivity (Mr) and coercivity value (Hc) for the Cu-MgFe2O4 sample were found to be 0.18453 emu, 39.584 × 10-3 emu and 139.61 Oe, respectively, while for the Cu-ZnFe2O4 sample, the values were 0.21271 emu, 71.022 × 10-3 emu and 285.91 Oe, respectively. The impact of copper doped nanoferrites on pollutant removal from pharmaceutical wastewater using the membrane Bioreactor (MBR) system has also been accomplished. The results demonstrated the effectiveness of ferrites in reducing concentrations of heavy metals, including lead and cadmium, within acceptable ranges for inland surface water and public sewers. Furthermore, the MBR system with ferrites exhibited efficient removal of fluoride, sulphide and radioactivity, ensuring compliance with the specified standards. Although the study exhibited the potential of ferrites in pollutants removal, further optimization is necessary to achieve complete compliance with water quality standards.

Preparation and Properties of Thermoregulated Seaweed Fibers Based on Magnetic Paraffin wax@calcium Carbonate Microcapsules

In order to enhance the application of thermoregulated materials, magnetic phase change microcapsules were prepared using a self-assembly method. Paraffin wax was chosen for its fine thermoregulation properties as the core material, while Fe3O4 nanoparticles doped in calcium carbonate served as the hybrid shell material. The microcapsules were then blended with sodium alginate and processed into seaweed fibers through wet spinning. The microstructure, thermal, and magnetic properties of the microcapsules were analyzed using scanning electron microscopy, energy dispersive X-ray spectroscopy, a laser particle size analyzer, an X-ray diffractometer, a differential scanning calorimeter, a thermogravimetric analyzer, and a vibrating sample magnetometer. The thermoregulation of the fibers was evaluated using a thermal infrared imager. The results indicated that the microcapsules had a uniform size distribution and good thermal properties. When the mass fraction of Fe3O4 nanoparticles was 8%, the microcapsules exhibited a saturation magnetization of 2.44 emu/g and an enthalpy value of 94.25 J/g, indicating effective phase change and magnetic properties. Furthermore, the thermoregulated seaweed fibers showed a high enthalpy value of 19.8 J/g with fine shape, offering potential for developing multifunctional fiber products.

Preparation and characterization of smart hydrogels (magnetic field responsive)

Iron nanoparticles were prepared by using the co-precipitation process, and then used to fabricate magnetic field-responsive hydrogel films. The magnetic nanoparticles' structural, physical-chemical, morphological, and magnetic characteristics and the effect of hydrogel films' coating concentration were studied. The properties of the hydrogel film responsive to the magnetic field were investigated using Fourier analysis spectroscopy infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and a vibration sample magnetometer (VSM). The results indicated that all samples showed good inter-integration of the constituent materials and their functional groups. The hydrogel film samples which were polycrystalline, had broad diffraction peaks and showed constant particle size with nearly spherical particles with rounded edges. The SEM image of the magnetic nanoparticles with and without coating was established for the accumulation of numerous nanoparticles with a 17 nm mean diameter. In addition, the magnetic properties of the magnetic field-sensitive hydrogel films were evident and sufficient for drug delivery to the desired location.

Structural, magnetic and electrical studies on nickel doped copper ferrite synthesized using sol-gel method

Nickel doped copper ferrite nanoparticles NixCu1-xFe2O4(x = 0.1, 0.3, 0.5, 0.7, and 0.9) have been prepared through well known sol-gel technique. Numerous analytical methods, including the Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and powder X-ray diffractometer (XRD), were used to analyze the synthesized materials. Synthesized sample XRD patterns reveal the single phase development of the spinel crystalline structure in the absence of any contaminant. The concentration of Ni ions rises with a corresponding decrease in crystallite size. Scanning electron microscopy (SEM) was also used to assess the microstructure. By using UV–Visible spectrometer an optical absorbance and through FTIR, two of ferrite's distinctive bands were verified. The M-H loops show that when the concentration of nickel ions increases, saturation magnetization varies. The Cyclic-Voltameter was used to perform the ionic electrochemical analysis. The NixCu1-xFe2O4 nanopowder's enhanced magnetic characteristics suggest that these substances would make good candidates for magnetic catalysts.

Structural, electrical and magnetic studies on Zn doped MnFe2O4 nanoparticles with via Sol-Gel approach

A manganese ferrite (MnFe2O4) nanoparticle is prepared through sol-gel method. The various concentration of Zn (x = 0.0, 0.1, 0.3, 0.5, 0.7, 0.9) was added to the initial solutions. Through X-Ray diffraction examinations results confirmed the cubic spinel structure of Mn1-xZnxFe2O4 and have larger crystallite size. The functional analysis is obtained through Fourier transform infrared spectroscopy (FTIR) analysis and it is indicated that Fe-O, Mn-O, and Zn-O vibrational bands. The optical analysis carried out through UV–visible spectrometer. The surface features with morphology and its content of elements in the samples were found through scanning electron microscope (SEM) with energy dispersive (EDAX) analysis. The energy analysis carried out through Xray Photo electro absorption (XPS) analysis. The detailed magnetic characteristics of the resulting samples such as cohersivity (Hc), magnetization (Ms), retentivity (Hr), squareness ratio (SQR) and anisotripic constant (Ki) were found through vibrating sample magnetometer (VSM), shows good magnetic property, multi grain wall and the strong dependents of Zn . The dielectric related parameters like dielectric constant for real and imaginary components, loss tangent with AC conductivity with respect to applied frequency are enhanced dielectric constant and at the same time it reduces the dielectric loss tangent discussed through LCR measurement. The electrochemical behaviour of the samples was tested through cyclic voltameter setup. Finally, concluded with their merits and demerits.

Structural, Morphology and Electromagnetic Interference Shielding Studies of Multifunctional Hybrids of Low-Density Polyethene with Graphene, Carbon Nanotube and Magnetite

ABSTRACT In this study, we investigate the EMI SE (Electromagnetic interference shielding effectiveness) of novel multifunctional polymer hybrids in the X-band and Ku-band frequencies. Magnetite nanoparticles were synthesized via wet chemical reduction and nanographene was synthesized through chemical exfoliation combined with microwave treatment. Nine different composites were prepared with varying weight ratios of graphene and magnetite. X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed their structural and morphological properties. SEM analysis revealed magnetite particle sizes ranging from 10.05 nm to 29.8 nm. Vibrating Sample Magnetometer (VSM) analysis indicated that the magnetite nanoparticles exhibit super paramagnetic behavior with a magnetic anisotropy constant (K) of approximately 63.9375 × 106 J/m3. Impedance analysis, permittivity and permeability measurements showed frequency-dependent behaviors, with interfacial polarization effects due to magnetite agglomeration. The highest conductivity, observed in the 50:5:37.5:7.5 hybrid, peaked at 8 S/cm at lower frequencies. The 50:5:37.5:7.5 hybrid demonstrated the highest EMI SE of 50.08 dB (99.999019% suppression) in the X-band, which is suitable for advanced EMI-shielding applications.

Facile microwave synthesis of various-shaped magnetite/ reduced graphene oxide heterostructures and their magnetization properties

Heterostructures of magnetite (Fe3O4) nanoparticles and reduced graphene oxide (RGO) sheets are very common composite materials for different applications such as catalysis, energy storage, and biomedicine. Developing methods for the facile control of the size and shape of both freestanding Fe3O4 nanoparticles and those anchored onto RGO sheets is in demand. Herein, we report on the rapid and facile microwave synthesis (MWS) of Fe3O4 nanoparticles and Fe3O4/RGO with various sizes and shapes using the oleylamine (OAm)/oleic acid (OAc) ligand pair. The solvothermal synthesis using microwave irradiation (MWI) resulted in the concurrent conversion of graphene oxide (GO) into RGO and the in-situ formation of various-shaped Fe3O4 on RGO sheets. Freestanding Fe3O4 nanoparticles of various shapes were prepared using MWS for comparison. The morphological, structural, and surface properties of the samples were studied using different characterization techniques. The magnetization properties of the prepared samples were determined using a vibrating sample magnetometer. Various-shaped standalone and RGO-supported Fe3O4 nanoparticles including nanospheres, nanocubes, and nanotriangles were synthesized via MWI at 1000 W for 20 min by changing the ratios of the iron precursor and the OAm/OAc ligand pair. Interestingly, the MWI using OAm/OAc ligand pair of a molar ratio of 3:4 resulted in the in-situ formation of large hexagonal Fe3O4/RGO. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results confirm the crystallinity and spinel structure of the prepared Fe3O4 samples and prove the concurrent conversion of GO into RGO with assemblies of Fe3O4 nanoparticles. The magnetization measurements further emphasized the role of size and shape in affecting the magnetic properties of Fe3O4 and Fe3O4/RGO heterostructures. The results identify the qualities of the prepared samples and prove the MWS as a facile one-pot method for the preparation of Fe3O4 and Fe3O4/RGO heterostructures.

Study of Fe3O4 and Cu2+ doped modified Fe3O4 nano catalyst for photocatalytic degradation of methylene blue and eriochrome black-T dyes: Synthesis, characterization, and antimicrobial assessment

This study presents the synthesis and characterization of undoped Fe3O4 and 3% Cu-doped Fe3O4 nanoparticles via a cost-effective and environmentally friendly co-precipitation method. A comprehensive suite of nanomaterial characterization techniques, including energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS), was employed to confirm the elemental composition, structural parameters, and chemical states of the prepared materials. Additionally, fragmentation analysis using LC–MS illustrated the structural stability and breakdown of the nanoparticles under specific conditions. Both the materials were characterized by vibrating sample magnetometer (VSM), Brunauer-Emmett-Teller (BET) for investigating the magnetic, and surface characteristics respectively. Furthermore, the synthesized nanoparticles were evaluated for their photocatalytic degradation efficiency towards methylene blue and eriochrome black T dyes. A systematic investigation of various parameters, including the pH of the dye solution, dye concentration over time, catalyst dose, dye concentration versus degradation, catalyst reusability, and kinetic study, was conducted to understand the factors influencing the photocatalytic activity of both undoped and Cu-doped Fe3O4 nanoparticles. The LC-MS analysis predicted the probable degradation pathways of MB and EBT dyes. This work provides insights into the sustainable synthesis, comprehensive characterization, and practical application of Fe3O4-based nanoparticles for water treatment applications, highlighting their potential as efficient and environmentally benign Photocatalyst for wastewater remediation. An investigation was conducted to investigate the antimicrobial properties of both undoped and doped nanoparticles. The minimum inhibitory concentration (MIC) of the synthesized nanoparticles were determined against the bacterial strains E. coli, P. aeruginosa, S. aureus, and S. pyogenes, as well as the fungal strains C. albicans, A. niger, and A. clavatus.

Dissociative Oxygen Adsorption and Incorporation in Co3O4-Dispersed BaZr0.9Sc0.1O2.95 for PCFC Cathode.

The development of air electrodes with superior surface oxygen exchange properties at intermediate temperatures is crucial for improving the efficiency of protonic ceramic fuel cells. This study evaluated the surface exchange properties of Co3O4 dispersed protonic conductors, BaZr0.9Sc0.1O2.95. Although Co3O4 is widely acknowledged as superior dissociative adsorption catalysts, there is still ambiguity regarding the enhancement mechanisms of their surface exchange properties by Co3O4, as well as their optimal composition to achieve high catalytic activity. To overcome these difficulties, this study elucidated the effect of the chemical states and composition of composites on their surface exchange properties by evaluating their chemical states and surface exchange reaction rates with several compositions prepared at different temperature conditions using a vibrating-sample magnetometer and the pulse isotope exchange technique. For samples annealed at a high temperature, it became evident that the surface exchange activity became the most active by adding only 1 vol % Co3O4 and indicated an abrupt decline above this composition despite an increase in the volume of the catalysts. This was attributed to the combined effect of the high dissociative adsorption activity of the Co-containing solid solutions formed at a high temperature and a decrease in oxygen vacancies due to hole compensation. For samples annealed at intermediate temperature, their chemical states remained unchanged from those of the original milled powders, and their surface exchange properties monotonically improved with an increase in the volume of Co3O4. Based on the results, different chemical states of composites derived from different preparation conditions lead to completely different activation behavior of the surface exchange reaction.

Research on cadmium-injected manganese ferrite made through the sol-gel method, focusing on its structure, magnetic properties, electrical conductivity, and electrochemical behavior

Cadmium was integrated into Manganese ferrite (Mn1-xCdxFe2O4) nanofine particles via the sol-gel method for potential sensing uses. The X-ray diffraction (XRD) revealed that the particles contained a cubic spinel structure and FTIR spectroscopy was employed to identify the metal-oxide (MO) stretching, bending and stretching vibrations. The purity of the samples and the surface feature were scrutinized using an energy dispersive X-ray (EDAX) spectrum and scanning electron microscope (SEM). The magnetic properties were examined as ferromagnetic found through a vibrating sample magnetometer (VSM). An LCR meter gives information on dielectric constants (ε’ & ε’’), loss (tanδ) with AC conductivity (σAC), and cyclic-voltammetry was used to evaluate the electrochemical properties, including voltage/current responses (V/I), Nyquist frequency, voltage/current response to SCR, and phase angle as a function of frequency. From the results the magnetic, dielectric, electrochemical behavior and etc., can be interpreted and discussed extensively.

Research on preparation and stability of high viscosity carbon nanotube-modified PAO20-based magnetic fluids

The preparation of high-performance magnetic fluids with high viscosity, high saturation magnetization and high stability, has remained a pivotal challenge limiting the advancement of associated applications. In the present study, we synthesized modified magnetic nanoparticles through an innovative approach combining in-situ carbon nanotube (CNT) generation with chemical co-precipitation. These nanoparticles were then co-coated with OA/PIBA, resulting in the preparation of advanced PAO20-based magnetic fluids. The effects of CNT modification on particle microstructure and magnetic properties were studied by transmission electron microscopy and vibrating sample magnetometer, the magnetoviscous properties of magnetic fluids were studied by a rotating rheometer equipped with a magnetic field module, and the stability of the prepared magnetic fluids under a strong magnetic field was tested by a self-made LC oscillation circuit. The results show that the saturation magnetization of the prepared magnetic fluids surpasses 32 emu/g, while their viscosity reaches a remarkable 6625 mPa·s (at 0.24 T, 100 1/s shear rate and 25 °C), which is significantly higher than that of traditional magnetic fluids (usually about 100 mPa·s). Furthermore, when exposed to a 0.6 T magnetic field, the magnetic fluids could exhibit Rosensweig instability that persists for over 468 h. The stability is at least 93 times superior to that of unmodified PAO20-based magnetic fluids. Based on these encouraging results, it can be fully predicted that the CNT-modified PAO20-based magnetic fluids developed in this study will play a pivotal role in various applications, including sealing, lubrication, and vibration reduction. Their exceptional properties will hold immense promise for numerous engineering applications.

Tailoring magnetism in chromium-doped zinc cobalt ferrite nanostructure for advanced spintronic memory devices

Soft magnetic ferrites serve as a crucial component in a wide array of sensing and actuating applications across various industries, including consumer electronics, automotive systems, spintronics, and more. These materials also find utility in spintronics, particularly for next-generation magnetic random-access memory (MRAM) due to their excellent inductive properties, which enhance the performance and scalability of spintronic memory devices. This study focuses on fine-tuning soft magnetic ferrites for inductive applications by doping them with Cr ions. By utilizing advanced experimental techniques such as the vibrating sample magnetometer (VSM) for bulk magnetometry and X-ray magnetic circular dichroism (XMCD) alongside X-ray absorption spectroscopy for atomic studies, the research aims to investigate the structural, electronic, and magnetic properties of the nanoferrites. Addition of doping in the soft ferrites observes reduction in the general magnetic parameters, with the only exception being coercivity, which decreases from 381 Oe to 275 Oe as the doping concentration increases from x = 0 to x = 0.02, and then increases to 350 Oe at x = 0.03. Through such precise tuning of the nanoparticles, this study aims to investigate the controllable soft magnetic properties of the nanoferrites, thereby paving the way for fast access times, non-volatility, and low energy consumption, presenting a compelling alternative to conventional memory technologies.

Synthesis and characterization of (Ba2Zn2Fe12O22)1−x(NiFe2O4)x ferrite composites for antenna applications

A series of (Ba2Zn2Fe12O22)1−x(NiFe2O4)x ferrites (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) were successfully synthesized by one-pot coprecipitation route. XRD analysis reveals the formation of Ba2Zn2Fe12O22 and NiFe2O4 composite after sintering calcined precursor powder at 1200 °C/4 h. Densification behaviour was evaluated by Archimedes’ principle. Field emission scanning electron microscopy was used to study morphological characteristics. Room temperature magnetization behaviour was evaluated using a vibrating sample magnetometer. In composite, it was observed that the saturation magnetization (Ms) and coercivity (Hc) increased with increasing NiF content. With the increase of NiF in the composite, the permittivity (ε) decreased from 28.6 (for x = 0.2) to 13.6 (for x = 0.8) with the corresponding decrease in dielectric loss (tanδε) at 100 MHz. The permeability (μ) also decreased from 21.3 (x = 0.2) to 17.9 (x = 0.8) with the associated decrease of the magnetic losses (tanδμ) at 100 MHz. Miniaturization factor (n) of 19.2 and characteristic impedance of 1.1 were obtained for x = 0.4 composition at 100 MHz along with low dielectric loss factor (tan δε/ε) and magnetic loss factor (tan δµ/µ). The ferrite resonator antenna was fabricated using FR4 as substrate and ferrite pellet as magneto-dielectric resonator material. The antenna characteristics parameters reflection loss S (1,1) and voltage standing wave ratio (VSWR) were measured by vector network analyser (VNA).

Adsorptive removal of Pb2+ from aqueous solution by magnetic biodegradable and polymeric cellulose/Nylon 6 @Fe3O4 nanocomposite encapsulated with chitosan

A novel polymeric magnetic nanocomposite adsorbent (CNCs/N6 @ Fe3O4–CT) of low-cost, biodegradable, and ultra-permeable materials was prepared and characterized. The adsorbent was used to evaluate the effect of influencing factors and competitive ions on the adsorption of Pb2+ ions. The obtained data was fitted to equilibrium and thermodynamic models. The chemical and structural features of the adsorbent were investigated using a range of characterization techniques, including a vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). FTIR confirmed the presence of OH–, –NH2, and FeO sorption sites. SEM micrographs revealed presence of visible pores on the surface of the adsorbent, while VSM established a magnetic strength of 26.90 emu/g. The adsorption data fitted well with Langmuir isotherm, whereas the adsorption kinetics followed the pseudo-second-order kinetic model with a coefficient of determination (R2 >0.98). The thermodynamic parameters indicated that the adsorption of Pb2+ was exothermic and spontaneously adsorbed. The adsorption process was dominated by a chemical process with E > 10 kJ/mole, indicating an ion exchange process. The results established that the synthesized CNCs/N6 @ Fe3O4–CT nanocomposite adsorbent is viable for the removal of metal ions from aqueous solutions and has the potential for optimization and scale-up.