In this work, the oxidation behavior of an aluminide coating at 900, 1000, and 1100 °C was investigated. The aluminide coating was prepared on a cobalt-based superalloy using a vapor phase aluminizing process, which is composed of a β-(Co,Ni)Al phase outer layer and a Cr-rich phase diffusion layer. The experimental results showed that the oxidation of the coating at 900-1100 °C all obey the parabolic law. The oxidation rate constants of the coating were between 2.19 × 10 and 47.56 × 10 mg·cm·s. The coating produced metastable θ-AlO at 900 °C and stable α-AlO at 1000 and 1100 °C. As the oxidation temperature increases, the formation of AlO is promoted, consuming large amount of Al in the coating, resulting in the transformation from β-(Co,Ni)Al phase to α-(Co,Ni,Cr) phase. And the decrease in the β phase in the coating led to the dissolution of the diffusion layer.
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http://dx.doi.org/10.3390/ma17235897 | DOI Listing |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643841 | PMC |
Environ Sci Pollut Res Int
January 2025
Post-Graduation Program in Ecology, Conservation, and Biodiversity, Federal University of Uberlândia, Uberlândia, MG, 38408144, Brazil.
Since the establishment of the COVID-19 pandemic, a range of studies have been developed to understand the pathogenesis of SARS-CoV-2 infection, vaccine development, and therapeutic testing. However, the possible impacts that these viruses can have on non-target organisms have been explored little, and our knowledge of the consequences of the COVID-19 pandemic for biota is still very limited. Thus, the current study aimed to address this knowledge gap by evaluating the possible impacts of oral exposure of C57Bl/6 J female mice to SARS-CoV-2 lysate protein (at 20 µg/L) for 30 days, using multiple methods, including behavioral assessments, biochemical analyses, and histopathological examinations.
View Article and Find Full Text PDFAdv Mater
January 2025
School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510641, China.
Understanding the behavior of high-entropy carbides (HECs) under oxygen-containing environments is of particular importance for their promising applications in structural components, catalysis, and energy-related fields. Herein, the structural evolution of (Ta, Ti, Cr, Nb)C (HEC-1) nanoparticles (NPs) is tracked in situ during the oxidation at the atomic scale by using an open-cell environmental aberration-corrected scanning transmission electron microscope. Three key stages are clearly discerned during the oxidation of HEC-1 NPs at the atomic level below 900 °C: i) increased amorphization of HEC-1 NPs from 300 to 500 °C due to the energetically favorable formation of carbon vacancies and substitution of carbon with oxygen atoms; ii) nucleation and subsequent growth of locally ordered nanocluster intermediates within the generated amorphous oxides from 500 to 800 °C; and iii) final one-step crystallization of non-equimolar MeO and MeO (Me = metallic elements, Ta, Ti, Cr, and Nb) high-entropy oxides above 800 °C, accompanied with the reduction in atomic defects.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China.
Layered transition metal oxide (NaTMO) cathodes are considered highly appropriate for the practical applications of sodium-ion batteries (SIBs) owing to their facile synthesis and high theoretical capacity. Generally, the phase evolution behaviors of NaTMO during solid-state reactions at high temperature closely related to their carbon footprint, prime cost, and the eventual electrochemical properties, while the thermal stability in various desodiated states associated with wide temperature fluctuations are extremely prominent to the electrochemical properties and safety of SIB devices. Therefore, in this review, the influences of sintering conditions such as pyrolysis temperature, soaking time, and cooling rates on the phase formation patterns of NaTMO are summarized.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
Diquat (DQ), a contact herbicide extensively utilized in both agricultural and nonagricultural domains, exhibits a high correlation with neuronal disorders. Nevertheless, the toxicity and underlying mechanisms associated with exposure to environmental concentrations of DQ remain ambiguous. Here, we report dose-dependent cellular neurotoxicity of DQ in .
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
The controllable synthesis of epitaxial nanopillar arrays is fundamentally important to the development of advanced electrical and optical devices. However, this fascinating growth method has rarely been applied to the bottom-up synthesis of plasmonic nanostructure arrays (PNAs) with many broad, important, and promising applications in optical sensing, nonlinear optics, surface-enhanced spectroscopies, photothermal conversion, photochemistry, etc. Here, a one-step epitaxial approach to single-crystalline NbTiN (NbTiN) nanopillar arrays based on the layer plus island growth mode is demonstrated by strain engineering.
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