The magnetic properties and magnetocaloric effect (MCE) in PrCaBaMnO have been investigated supplemented by electrical data. X-ray diffraction shows that the sample crystallizes in the distorted orthorhombic system with the space group. PrCaBaMnO undergoes paramagnetic-ferromagnetic (PM-FM) phase transition at ∼ 85 K. For a magnetic field change of 5 T, the maximum value of the magnetic entropy change (-Δ ) is estimated to be 4.4 J kg K around with a large relative cooling power (RCP) value of 263.5 J kg. While the modified Arrott plots suggested that the magnetic transition belongs to the second order phase transitions, the universal curves of the rescaled magnetic entropy (Δ ) proved the opposite. The electrical properties of PrCaBaMnO have been investigated using impedance spectroscopy techniques. The dc-resistivity ( ) study shows the presence of semiconductor behavior. Ac-conductivity ( ) analysis shows that the conductivity is governed by a hopping process. From the analysis of the alternating regime, the exponent variation obtained is in good agreement with Mott theory. The impedance spectrum analysis reveals the presence of a relaxation phenomenon. Based on these analyzes, the sample can be modeled by an electrical equivalent circuit.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9085919 | PMC |
http://dx.doi.org/10.1039/c8ra05747h | DOI Listing |
Bioelectromagnetics
January 2025
Seibersdorf Labor GmbH, Seibersdorf, Austria.
The electrical conductivity of human tissues is a major source of uncertainty when modelling the interactions between electromagnetic fields and the human body. The aim of this study is to estimate human tissue conductivities in vivo over the low-frequency range, from 30 Hz to 1 MHz. Noninvasive impedance measurements, medical imaging, and 3D surface scanning were performed on the forearms of ten volunteer test subjects.
View Article and Find Full Text PDFAnal Methods
September 2020
College of Life Sciences, Fujian Normal University, Fuzhou 350117, Fujian, China.
An innovative magnetic immunoassay was developed for the voltammetric detection of carbohydrate antigen-125 (CA-125) on a home-made microfluidic device including a multisyringe pump, selection valve and magneto-controlled detection cell. Two kinds of biofunctionalized nanostructures including anti-CA-125 capture antibody-conjugated magnetic beads and anti-CA-125 detection antibody-labeled silver-polypyrrole (Ag-PPy) nanohybrids were utilized for a sandwiched immunoreaction in the presence of CA-125. With the help of an external magnet, the formed magnetic immunocomplexes were attached to the sensing interface to activate the electrical contact between Ag-PPy nanohybrids and the base electrode, thus resulting in the switching on of the sensor circuit for the generation of voltammetric signals thanks to electroactive Ag-PPy nanohybrids.
View Article and Find Full Text PDFJ Physiol Anthropol
January 2025
University of Wrocław, Wrocław, Poland.
Background: The oxidative handicap hypothesis posits that testosterone-dependent traits, such as muscle mass and strength, may be costly to develop due to testosterone's pro-oxidative properties, leading to increased oxidative stress. This hypothesis suggests that only individuals with superior biological conditions can afford these costs. This study examines the oxidative handicap hypothesis, exploring the relationship between muscle mass or handgrip strength and oxidative stress markers in men.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Electrical Engineering, Indian Institute of Technology, Gandhinagar, Gujarat, India.
Graphene quantum dots (GQDs) are highly valued for their chemical stability, tunable size, and biocompatibility. Utilizing green chemistry, a microwave-assisted synthesis method was employed to produce water-soluble GQDs from Mangifera Indica leaf extract. This approach is efficient, cost-effective, and environmentally friendly, offering reduced reaction times, energy consumption, and uniform particle sizes, and has proven advantageous over other methods.
View Article and Find Full Text PDFNat Commun
January 2025
Institute of Optoelectronic Thin Film Devices and Technology, Key Laboratory of Optoelectronic Thin Film Devices and Technology of Tianjin, College of Electronic Information and Optical Engineering, National Institute for Advanced Materials, Nankai University, Tianjin, China.
Biological neural systems seamlessly integrate perception and action, a feat not efficiently replicated in current physically separated designs of neural-imitating electronics. This segregation hinders coordination and functionality within the neuromorphic system. Here, we present a flexible device tailored for neuromorphic computation and muscle actuation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!