Ni-Mn-based Heusler alloys are known to demonstrate magnetic shape memory and giant magnetocaloric effect (MCE). These effects depend on the phases, crystallographic and magnetic phase transitions, and the crystallographic texture characteristics. These structural characteristics, in turn, are a function of the processing parameters. In the current work, NiMnGaSi Heusler alloy was processed by melt-spinning under a helium atmosphere. This process results in a fine microstructure. The ribbon that was produced with a narrower nozzle width, faster wheel speed, and higher cast temperature, indicating a faster cooling rate, had double the magnetic entropy change close to room temperature. However, the other ribbon demonstrated a large entropy change over a broader temperature range, extending its usability. The effect of the melt-spinning process parameters on the developing microstructure, crystallographic structure and texture, transformation temperatures, and the magnetic entropy change were studied to explain the difference in magnetocaloric behavior.
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http://dx.doi.org/10.3390/ma16196590 | DOI Listing |
Biosystems
January 2025
ICube Laboratory, UMR 7357, Department of Mechanics, Civil Engineering and Energetics Team - GCE, CNRS, University of Strasbourg, INSA Strasbourg, Department of Architecture, 24 Boulevard de la Victoire, 67084 Strasbourg Cedex, France; MAP-Aria Laboratory, UMR CNRS/MCC 3495, École Nationale Supérieure d'Architecture de Lyon, 3 rue Maurice Audin, BP 170, 69512 Vaulx-en-Velin Cedex, France. Electronic address:
This paper explores the intersections of constructal thermodynamics, and its semantic ontology within the context of autopoetic, digital and computational design in protocell inspired numerical architectural and urban narratives that are examined here as open systems. Constructal law is the thermodynamic theory based on the analysis of fluxes across the border of an open system. Protocells, as dynamic and adaptive open finite size systems, serve in this paper as a compelling metaphor and design model for responsive and sustainable manmade architectural and urban environments.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Tel Aviv University, School of Mechanical Engineering and Center for Physics and Chemistry of Living Systems, 69978 Tel Aviv, Israel.
Materials that are constantly driven out of thermodynamic equilibrium, such as active and living systems, typically violate the Einstein relation. This may arise from active contributions to particle fluctuations which are unrelated to the dissipative resistance of the surrounding medium. We show that in these cases the widely used relation between informatic entropy production and heat dissipation does not hold.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; Shandong Energy Institute, Qingdao 266101, China; Qingdao New Energy Shandong Laboratory, Qingdao 266101, China. Electronic address:
Metamorphic proteins switch reversibly between distinctly different folds often with different functions under physiological conditions. Here, the kinetics and thermodynamics of the fold-switching at different temperatures in a metamorphic protein, KaiB, involved in cyanobacterial circadian clock, reveal that enthalpy-driven the fold-switching to form fold-switched KaiB (fsKaiB) and the fsKaiB and ground-state KaiB (gsKaiB) are more dominantly at lower and higher temperatures, respectively. Thermodynamic analysis indicates that conformational and solvent entropy have opposing effects on KaiB's fold-switching.
View Article and Find Full Text PDFJ Environ Manage
January 2025
School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China; Qilaotu Mountain National Observation and Research Station of Chinese Forest Ecosystem, Chifeng, 024400, China.
Climate change has profound implications for the distribution of suitable habitats for woody species. In this study, we assessed the optimal distribution thresholds for twelve woody species on the Loess Plateau using the Maximum Entropy (MaxEnt) model, incorporating sample points of tree species alongside relevant environmental variables. We analyzed the sustainability of potentially suitable zones and proposed a framework for selecting a regulatory model to establish the most suitable creation zones in response to future climate change.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Geomatics Engineering, Hacettepe University, 06800, Beytepe, Ankara, Türkiye.
This study presents a hybrid methodology for planning green spaces to enhance urban sustainability and livability, evaluating the impacts of climate change on cities. Cities, once accommodating a small population, have become major centers of migration and development since the eighteenth century. Rapid urban growth intensifies infrastructure, environmental, and social challenges.
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