Enhanced magnetic properties of polymer-magnetic nanostructures synthesized by ultrasonication

Polymer based nickel (Ni) and cobalt (Co) co-doped ferrites were prepared by adept ultrasonication route. Different concentrations of polymer [polyvinyl alcohol (PVA)] (0.2 g and 0.5 g) was added as a surfactant to the magnetic particles. The phase purity of Ni-Co ferrites (spinel structure) was confirmed by X-ray diffraction (XRD). Enhanced saturation magnetization of polymer based magnetic nanoparticles due to shape anisotropy and size. 0.2 wt% doped ferrite showed superparamagnetic characteristics with blocking temperature above room temperature. Hence, ultrasonication route is a rapid and effective technique for tailoring size and morphology of magnetic nanostructure that could be useful in magnetic-sensor applications

Impact of Dopants on the Electrical and Optical Properties of Hydroxyapatite

This chapter deals with the effect of alternating electrical current on hydroxyapatite [HAp, Ca10(PO4)6(OH)2] and doped HAp along with their optical response and the processes involved. The dielectric constant, permittivity and ac conductivity were analyzed to have an insight into the surface charge polarization phenomenon. Further, the magnitude and the polarity of the surface charges, microstructure, and phases also play significant role in the cell proliferation and growth on the implants. Besides, the mechanism behind the electrical properties and the healing of bone fracture are discussed. The influence of various dopants on the optical properties of HAp viz., absorbance, transmission, band gaps and defects energy levels are analyzed along with the photoluminescence and excitation independent emission. In the future outlook, the analysis of effect of doping is summarized and its impact on the next generation biomaterials are elucidated

Enhanced magnetic properties of polymer-magnetic nanostructures synthesized by ultrasonication

Polymer based nickel (Ni) and cobalt (Co) co-doped ferrites were prepared by adept ultrasonication route. Different concentrations of polymer [polyvinyl alcohol (PVA)] (0.2 g and 0.5 g) was added as a surfactant to the magnetic particles. The phase purity of Ni-Co ferrites (spinel structure) was confirmed by X-ray diffraction (XRD). Enhanced saturation magnetization of polymer based magnetic nanoparticles due to shape anisotropy and size. 0.2 wt% doped ferrite showed superparamagnetic characteristics with blocking temperature above room temperature. Hence, ultrasonication route is a rapid and effective technique for tailoring size and morphology of magnetic nanostructure that could be useful in magnetic-sensor applications

Novel multifunctional of magnesium ions (Mg++) incorporated calcium phosphate nanostructures

Magnesium ions incorporated calcium phosphate was synthesized by wet chemical route and followed by microwave assisted method. XRD analysis was confirmed that the presence of calcium phosphate (hydroxyapatite). TEM analysis was exhibited rod-like morphology. XRF results were showed the percentage of calcium, phosphate, magnesium and oxygen. There was a slight blue shift observed in magnesium ions based samples. Higher magnesium (0.1 Mg-HAp) was revealed the greater discharging time with capacitance voltage (0.55 V). Magnesium based calcium phosphate was showed prolonged rate of drug release. At higher frequency, the Nyquist plot was showed the electrochemical behavior, however at lower frequency, revealed mass transfer process. Magnesium ions tailor the specific capacitance of calcium phosphate. Therefore, magnesium ions based phosphate samples could be an outstanding multifunctional candidate for drug release and supercapacitor applications

Enhanced anticorrosion properties of nitrogen ions modified polyvinyl alcohol/Mg-Ag ions co-incorporated calcium phosphate coatings

Nitrogen ions (70 keV) were implanted on composite coatings containing polymer/Mg (magnesium)–Ag (silver) ions co-incorporated hydroxyapatite which is developed by microwave irradiation. Average crystallite size of modified coatings is reduced to 80% compared to pristine. The variation of bond strength of modified coatings is realized. The electrical resistance (77%), microhardness (4.3%), roughness (4.5 times) and pore size are enhanced on the modified coatings. Superhydrophilic surface is tuned to hydrophobic on implantation. At higher fluence (1×1017 ions/cm2) depicted an enhanced corrosion potential compared to the other coatings. Thus, the new insight of modified coatings is realized by correlating phase-structure, surface and anticorrosion

Design and finite element simulation of metal-core piezoelectric fiber/epoxy matrix composites for virus detection.

From PubMed via Jisc Publications RouterHistory: received 2020-12-01, revised 2021-03-17, accepted 2021-04-02Publication status: ppublishUndoubtedly, the coronavirus disease 2019 (COVID-19) has received the greatest concern with a global impact, and this situation will continue for a long period of time. Looking back in history, airborne transimission diseases have caused huge casualties several times. COVID-19 as a typical airborne disease caught our attention and reminded us of the importance of preventing such diseases. Therefore, this study focuses on finding a new way to guard against the spread of these diseases such as COVID-19. This paper studies the dynamic electromechanical response of metal-core piezoelectric fiber/epoxy matrix composites, designed as mass load sensors for virus detection, by numerical modelling. The dynamic electromechanical response is simulated by applying an alternating current (AC) electric field to make the composite vibrate. Furthermore, both concentrated and distributed loads are considered to assess the sensitivity of the biosensor during modelling of the combination of both biomarker and viruses. The design parameters of this sensor, such as the resonant frequency, the position and size of the biomarker, will be studied and optimized as the key values to determine the sensitivity of detection. The novelty of this work is to propose functional composites that can detect the viruses from changes of the output voltage instead of the resonant frequency change using piezoelectric sensor and piezoelectric actuator. The contribution of this detection method will significantly shorten the detection time as it avoids fast Fourier transform (FFT) or discrete Fourier transform (DFT). The outcome of this research offers a reliable numerical model to optimize the design of the proposed biosensor for virus detection, which will contribute to the production of high-performance piezoelectric biosensors in the future. [Abstract copyright: © 2021 Elsevier B.V. All rights reserved.

Improving electrochromic properties of V2O5 smart film through Ti incorporation: Local atomic and electronic perspectives

In this work, vanadium pentoxide (V2O5) and titanium-modified V2O5 thin films were synthesized using the sol-gel spin coating route. The effect of Ti-doping concentration on the electrochromic optical properties and atomic/electronic structures of V2O5 smart thin films is examined. As the doping concentration of Ti increases, the surface roughness of the films is reduced. The structure of the films is analyzed using X-ray diffraction (XRD) and Raman spectroscopy, while the electrochromic modulation of atomic and electronic structures is elucidated through Raman and X-ray absorption spectroscopy (XAS) conducted during lithiation and delithiation. The XRD patterns demonstrate that an increase in Ti concentration leads to a more amorphous structure of the films and a shift of the main diffraction peak to a lower angle, attributable to the enlarged spacing between the stacking layers resulting from the incorporation of Ti ions. Soft X-ray absorption spectroscopy (XAS) and in situ hard XAS of the V L-edge, the O K-edge, and the V K-edge revealed a reduction in the charge state of V and local atomic structural symmetry modification upon lithated coloration and delithiated bleaching process. The critical insights provided by in situ XAS provides reveal that a small amount of Ti has the ability to modify the interlayer distance and local atomic structure of V2O5, thereby improving its electrochromic switching rate and stability when utilized in smart windows