Multiferroic BaMnF4 powder was prepared by hydrothermal method. Hysteretic field dependent magnetization curve at 5 K confirms the weak ferromagnetism aroused from the canted antiferromagnetic spins by magnetoelectric coupling. The blocking temperature of 65 K for exchange bias coincides well with the peak at 65 K in the zero-field cooled temperature-dependent magnetization curve, which has been assigned to the onset temperature of two-dimensional antiferromagnetism. An upturn kink of exchange field and coercivity with decreasing temperature was observed from 40 K to 20 K, which is consistent with the two-dimensional to three-dimensional antiferromagnetic transition at Néel temperature (~26 K). In contrast to the conventional mechanism of magnetization pinned by interfacial exchange coupling in multiphases, the exchange bias in BaMnF4 is argued to be a bulk effect in single phase, due to the magnetization pinned by the polarization through magnetoelectric coupling.
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http://dx.doi.org/10.1038/srep18392 | DOI Listing |
Sci Rep
January 2025
Computer Science Department, Al Al-Bayt University, Mafraq, 25113, Jordan.
Electrochemical energy conversion technologies include proton exchange membrane fuel cells (PEMFCs) where proton interchange is an alternative to diesel distributed generation, and PEMFCs are considered as a promising backup power source and a tool to regulate power consumption. Some of the major benefits of these PEMFCs especially in power system applications include low emission of carbon, fast load following capability, no noise and high start-up reliability. It is challenging to find the best PEMFC parameters because the model is complex and the problem is nonlinear; not all optimization algorithms can solve this problem.
View Article and Find Full Text PDFACS Nano
January 2025
Center of Free Electron Laser & High Magnetic Field, Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
Recently, two-dimensional (2D) van der Waals (vdW) magnetic materials have emerged as a promising platform for studying exchange bias (EB) phenomena due to their atomically flat surfaces and highly versatile stacking configurations. Although complex spin configurations between 2D vdW interfaces introduce challenges in understanding their underlying mechanisms, they can offer more possibilities in realizing effective manipulations. In this study, we present a spin-orthogonal arranged 2D FeGaTe (FGaT)/CrSBr vdW heterostructure, realizing the EB effect with the bias field as large as 1730 Oe at 2 K.
View Article and Find Full Text PDFJ Diabetes
January 2025
Department of Pharmacy, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China.
Objective: Provide an evidence-based basis for the selection of cardiovascular benefit drugs in Type 2 diabetes mellitus (T2DM) patients with cardiovascular disease (CVD).
Methods: Conduct a comprehensive search of all relevant literature from PubMed, Embase, Web of Science, Cochrane Library, and Clinical Trials.gov from their establishment until December 13, 2023, and select randomized controlled trials (RCTs) that meet the pre-established inclusion and exclusion criteria.
Nat Commun
January 2025
State Key Laboratory of Millimeter Waves, School of Information Science and Engineering, Southeast University, Nanjing, China.
Microwave-optical interaction and its effective utilization are vital technologies at the frontier of classical and quantum sciences for communication, sensing, and imaging. Typically, state-of-the-art microwave-to-optical converters are realized by fiber and circuit approaches with multiple processing steps, and external powers are necessary, which leads to many limitations. Here, we propose a programmable metasurface that can achieve direct and high-speed free-space microwave-to-laser conversion.
View Article and Find Full Text PDFInt J Sports Physiol Perform
January 2025
Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel, Basel, Switzerland.
To define training zones, ventilatory thresholds (VTs) are commonly established by cardiopulmonary gas-exchange analysis during incremental exercise tests. Portable near-infrared spectroscopy (NIRS) devices have emerged as a potential tool for detecting these thresholds by monitoring muscle oxygenation. This study evaluated the accuracy of NIRS measurements to determine VTs or critical power (CP) based on muscle oxygen saturation and assesses the device's consistency across 2 constant-load tests.
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