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La 0.7 Sr 0.3 MnO 3 magnetic nanoparticles are synthesized by a solution combustion method and functionalised with polyvinyl alcohol and polyethylene glycol. The induction heating characteristics of coated magnetic nanoparticles (42 °C) were observed at a reasonably low concentration (5 mg/mL). Remarkably, coated magnetic nanoparticles exhibited a promisingly high specific absorption rate with varying magnetic field and constant frequency. The surface analysis is carried out by X-ray photoelectron spectroscopy. A reduction in the agglomeration of the particles was observed when the magnetic nanoparticles were functionalised with polyvinyl alcohol or polyethylene glycol and can be confirmed by transmission electron microscopy and dynamic light scattering studies. Vibrating sample magnetometer measurements indicate superparamagnetic behaviour at room temperature before and after coating. Colloidal stability revealed a considerably higher zeta potential value for coated system. In vitro cytotoxicity test of the magnetic nanoparticles indicates that coated nanoparticles have no significant effect on cell viability within the tested concentrations (1–5 mg mL -1 ) as compared to uncoated La 0.7 Sr 0.3 MnO 3 . All these findings explore the potentiality of La 0.7 Sr 0.3 MnO 3 nanoparticles for magnetic fluid hyperthermia. [ABSTRACT FROM AUTHOR]

Abstract: Structural, magnetic properties and an alternating current (AC) magnetic heating characteristics of Co0.5Zn0.5Fe2O4 nanoparticles (CZF NPs) have been investigated with respect to the possible application for magnetic hyperthermia treatments. The Specific Absorption Rate (SAR) was measured in alternating magnetic fields of 167.5–335.2Oe at fixed frequency of 265kHz. CZF NPs were fabricated by the chemical co-precipitation method using sodium hydroxide (NaOH) as the precipitating agent. The morphology of the particles was analysed by Transmission Electron microscopy (TEM). The TEM reveals that the grains are nearly spherical in shape with average particles size of 19nm. X-ray diffraction pattern indicated the sole existence of cubic spinel phase of CZF NPs. The magnetization (Ms) of CZF NPs was measured at room temperature (300K) using a Vibrating Sample Magnetometer (VSM). The magnetic heating ability of NPs was studied with an induction heating system. A highest SAR value of 114.98W/g for 5mg/mL sample concentration (265kHz, 335.2Oe) was determined. [Copyright &y& Elsevier]

Abstract: This paper reports the use of nonresonating microstripline for investigation of polyaniline thin film using overlay technique. Microwave absorption, DC conductivity, microwave conductivity, shielding effectiveness and microwave permittivity and dielectric loss of the conducting PANI films are reported. DC conductivity was between 0.15×10−3 and 3.13×10−3 S/cm. Microwave conductivity was between 0.1 and 10S/cm. The PANI films coated on alumina gave shielding effectiveness values of −1 to −8db. The ε′ was between 40 and 350. Measurements have been carried out over the frequency range 8.2–18GHz. The effect of thickness of the overlay is also reported. [Copyright &y& Elsevier]