A detailed study on the structural, magnetic, and transport properties of a monovalent (Na+) doped Pr0.75Na0·25MnO3 (PNMO) compound has been carried out. Temperature (T) and magnetic field (H) ...dependent magnetization (M), and resistivity (ρ) measurements have been carried out which reveal a second-order magnetic phase transition around TC = 60 K accompanied by a metal-insulator transition around TMI = 138 K. Magnetization measurements also confirm the coexistence of antiferromagnetic (AFM) and ferromagnetic (FM) components in the low-temperature regime. M − H has been used to calculate the magnetocaloric behavior and the system is found to show a maximum magnetic entropy change i.e. –ΔSmax as 2.54 J kg −1.K −1 for the field change of 5 T. Temperature dependence resistivity has been measured under the applied magnetic field and the system exhibits a colossal magnetoresistance (≅ 81%). Spin-polarized tunneling (SPT) model is applied to explain magnetoresistance (MR) phenomenon under applied magnetic field. Analysis of zero-field resistivity data signifies that a transition from Mott-VRH to Efros-Shklovskii-VRH (ES-VRH) conduction occurs in the low-temperature region in this present PNMO system.
Immobilisation of copper acetate onto a modified polystyrene provided a polymer-supported copper(II) Schiff base catalyst, which is effective in the O-arylation reaction of phenols with aryl halides ...to give diaryl ethers in high yields. This catalyst is air-stable and was recycled for five times with minimal loss of activity.
Extensive monitoring of particulate matter (PM) smaller than 2.5 µm, i.e., PM2.5, is critical for understanding changes in local air quality due to policy measures. With the emergence of low-cost air ...quality sensor networks, high spatiotemporal measurements of air quality are now possible. However, the sensitivity, noise, and accuracy of field data from such networks are not fully understood. In this study, we use spectral analysis of a 2-year data record of PM2.5 from both the Environmental Protection Agency (EPA) and PurpleAir (PA), a low-cost sensor network, to identify the contributions of individual periodic sources to local air quality in Chicago. We find that sources with time periods of 4, 8, 12, and 24 h have significant but varying relative contributions to the data for both networks. Further analysis reveals that the 8 and 12 h sources are traffic-related and photochemistry-driven, respectively, and that the contributions of both these sources are significantly lower in the PA data than in the EPA data. The presence of distinct peaks in the power spectrum analysis highlights recurring patterns in the air quality data; however, the underlying factors contributing to these peaks require further investigation and validation. We also use a correction model that accounts for the contribution of relative humidity and temperature, and we observe that the PA temporal components can be made to match those of the EPA over the medium and long term but not over the short term. Thus, standard approaches to improve the accuracy of low-cost sensor network data will not result in unbiased measurements. The strong source dependence of low-cost sensor network measurements demands exceptional care in the analysis of ambient data from these networks, particularly when used to evaluate and drive air quality policies.
Photonic crystal slab waveguides (PCSWs), based on the novel magnetooptic material, yttrium iron garnet (YIG), have been designed in order to enable fully integrated optical isolators. The PCSWs ...possess fundamental bandgaps for even (transverse-electric (TE)-like) modes around the wavelength of 1.33 μm. Propagation losses for both the TE-like and transverse-magnetic (TM)-like polarizations with various orientations have been investigated numerically using partial-wave analysis and a three-dimensional finite-difference time-domain method. The resulting PCSW designs can be used to isolate TE-like modes from TM-like modes and vice versa with isolation ratios of -60 and -40 dB, respectively. One of the main benefits of these designs is that they provide interface-free polarizers for the garnet waveguides. The designs can easily be extended to 1.55 μm for further versatility.
Though the significance of TMA as an etiological factor of hypertension in IgA nephropathy has been poorly understood, this finding should be actively searched for especially in patients with similar ...clinical phenotype.
Orexins (hypocretins) and the melanin-concentrating hormone (MCH) are neuropeptides localized to the lateral hypothalamic area and are potential regulators of energy homeostasis. Using highly ...sensitive radioimmunoassay for orexins and MCH, we determined their contents in the lateral hypothalamus (LH) of genetically obese
ob/
ob and
db/
db mice and their controls, C57BL/6J and C57BL/KSJ. The orexin contents in the lateral hypothalamus significantly increased in the
ob/
ob mice, whereas the orexin contents significantly decreased in the
db/
db mice. Mature orexin-A and -B peptides were the major endogenous orexin molecules in the lateral hypothalamus. Conversely, the MCH contents in the lateral hypothalamus of both obese mice increased compared to the control mice. MCH contents in the lateral hypothalamus were two- to five-fold higher than that of orexin contents. These results suggest that the regulatory mechanism of orexin and MCH may be different in the genetically obese mice.
In this letter, throughput performance of radio frequency (RF) energy harvesting-based multihop decode forward relay network with a novel adaptive harvesting scheme is proposed and performance is ...investigated. In the proposed adaptive power splitting scheme, the power splitting factors are adjusted dynamically to achieve the maximum end to end signal-to-noise ratio (SNR) by equalising the SNR at all nodes. The statistics of variation of power splitting factors of each node are reported. The simulation results show that the performance of the proposed scheme outperformed in comparison with the conventional scheme in terms of throughput and outage probability.
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