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Abstract: Magnetocaloric properties of Ni2.29Mn0.89Ga0.82, a Ga deficient and Ni rich composition have been studied. It has been shown that an optimum shape of magnetic entropy change versus temperature curve results in large refrigeration capacity (RC) of 100 J/Kg in an applied field of 5T, around 319 K. [Copyright &y& Elsevier]

In this paper, we present a dual wide-band ingestible antenna design for wireless capsule endoscopy (WCE) biotelemetry applications. The design process employs Characteristic Mode Analysis (CMA) and driven modal analysis. The effectiveness of the prototype antenna is afterward assessed through measurements using a tissue-equivalent phantom liquid model. We investigate the effects of antenna implantation depth and capsule shell thickness on its performance, providing insights into practical considerations. The proposed dual-band antenna demonstrates good performance in both the 1.4 GHz Wireless Medical Telemetry Services (WMTS) and 2.45 GHz Industrial, Scientific, and Medical (ISM) bands, exhibiting measured impedance bandwidths of 36% and 22%, respectively. The measured peak realized gains are −22.9 dBi and −25.3 dBi for the WMTS and ISM bands, respectively, with a compact footprint of 78.5 mm2. To ensure health and safety and optimal performance, we evaluate the antenna's specific absorption rate (SAR) and link margin (LM). Additionally, we assess the performance of the proposed antenna in comparison with the state-of-the-art design for capsule antennas in WCE applications. [ABSTRACT FROM AUTHOR]

We have studied the magnetic behavior of YMn 1− x Fe x O 3 ( x =0 and 0.2) nanoparticles synthesized by conventional solid state reaction method. The as-synthesized nanoparticles were found to have hexagonal phase with P6 3 cm space group confirmed by X-Ray diffraction. The particle size was found to be ~70 nm as confirmed by both X-Ray diffraction and Transmission Electron Microscopy. DC magnetization and memory effect measurements imply that the h-YMnO 3 nanoparticles bear a resemblance to super spin-glass state following de Almeida–Thouless like behavior which is being suppressed by Fe-doping. The Fe-doping in YMnO 3 enhances the antiferromagnetic (AFM) transition temperature T N to ~79 K and induces a new magnetic state due to the surface spins which is realized as diluted antiferromagnet in a field (DAFF) as explored by the thermoremanent and isothermoremanent magnetization measured with different applied magnetic field. [ABSTRACT FROM AUTHOR]

The structural and magnetic properties of polycrystalline Nd 2 NiMnO 6 (NNMO) synthesized by solid state reaction method have been investigated. Rietveld refinement of Powder X-Ray diffraction data suggests that NNMO compound crystallizes in monoclinic phase with space group P 2 1 / n. Magnetic measurements reveal an additional magnetic transition T C ׳ ~85 K due to to Ni 3+ –O–Mn 3+ antiferromagnetic superexchange interaction along with ferromagnetic transition ~196 K in M–T curve, leading to antiferromagnetic interactions in this compound. High sintering temperature (upto 1100 °C) leads to the formation of antisite disorders and antiferromagnetic antiphase boundaries in the present sample. The magnetic hysteresis measurements show ferromagnetic behavior with low saturation magnetization value (~2 μ B /f.u.) than the theoretical spin-only value (5 μ B /f.u.) of Ni/Mn ions. Hence, antisite disorders diminish the long range ferromagnetic ordering and also affect the magnetic properties of this compound. Exchange bias behavior has been observed in the hysteresis loops when the sample was field cooled from 300 K to 5 K. Exchange coupling between the ferromagnetic moments and antiferromagnetic antiphase boundaries is responsible for the observation of exchange bias in the present system. [ABSTRACT FROM AUTHOR]

Epitaxial thin films of double perovskite Nd 2 NiMnO 6 (NNMO) have been successfully grown on (001) oriented substrates of (LaAlO 3 ) 0.3 -(Sr 2 AlTaO 6 ) 0.7 (LSAT), SrTiO 3 (STO) and LaAlO 3 (LAO) by pulsed laser deposition under optimum growth conditions. X-Ray diffraction and reciprocal space maps of the asymmetric (103) peak reveal that the films deposited on LSAT and STO substrates are fully relaxed, while a large in- plane compressive strain has been observed in film grown on LAO. This results into the coexistence of anti-site disorder and orthorhombic phase in the film deposited on LAO, which is further confirmed from observed shift and broadening in the antisymmetric vibrations in the Raman spectra. The temperature dependent magnetization shows a ferromagnetic transition close to 200 K in all the three samples. However, film grown on LAO substrate shows an additional upturn transition at ~ 96 K ( T ′), which could be ascribed to the formation of antisite disorders further responsible for reduction of saturation magnetization (~ 1.8 × 10 5 A/m) in hysteresis curve of the sample. The ordered structure obtained on LSAT and STO exhibit in-plane easy axis with a large coercivity of ~ 0.2 T, while, the film deposited on LAO does not show any preferred anisotropic direction. [ABSTRACT FROM AUTHOR]