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Uniform distribution of particles and crack suppression in dried particulate deposits are major challenges for applications in coating and printing technologies. To address this, we investigated the impact of the addition of a water-soluble polymer, poly(vinyl alcohol) (PVA), on the evaporative self-assembly and kinetics of crack formation in deposits of anisotropic colloids. The fluid flow inside the drying drop is significantly altered due to polymer-mediated adsorption of ellipsoids to the drop surface. The competition between outward capillary flow and Marangoni flow developed in the drying colloid-polymer dispersion drop dictates the distribution of particles in the final dried patterns. The deposits formed by drying drops of ellipsoids dispersed in PVA solutions show three distinct patterns depending on the PVA concentration. A transition from ring-like deposit to uniform deposition with intermittent cracks was observed for a critical PVA concentration of 0.3 wt %. Radial as well as annular cracks were observed in the case of no PVA, while only annular cracks were formed in the dried patterns as the PVA content increased, thus indicating the change of capillary stresses in the films. Analyses of the particle dynamics and deposition patterns confirmed the effectiveness of gelation-driven crack prevention. This method offers a facile and straightforward solution for obtaining crack-free coatings in drying-mediated colloidal nanoparticle assembly.
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http://dx.doi.org/10.1021/acs.langmuir.4c00754 | DOI Listing |
Angew Chem Int Ed Engl
September 2025
Engineering Research Center of the Ministry of Education for Advanced Battery Materials, School of Metallurgy and Environment, Central South University, Changsha, 410083, P.R. China.
Intragranular cracks have been identified as a direct reflection of failure in high-energy-density cathodes, especially for high-Ni Co-free cathodes with severe electrochemical-mechanical degradation. Here we show that antiphase boundaries (APBs) are prone to form in high-Ni Co-free cathodes and demonstrate their crucial role in determining the formation of intragranular cracks. The results show that the APBs grain boundaries are continuously expand during the electrochemical process, and their presence promotes the formation and accumulation of heterogeneous internal stresses within the layered structure, which in turn facilitates the nucleation and expansion of intragranular cracks.
View Article and Find Full Text PDFInt J Food Microbiol
August 2025
Institute of Nutrition and Functional Foods (INAF), Université Laval, Quebec City, QC, Canada. Electronic address:
Transmission of foodborne viruses such as human norovirus (HuNoV) and hepatitis A virus (HAV) via frozen berries has become a significant public health concern. In this study, we investigated the long-term persistence of murine norovirus-1 (MNV-1, a HuNoV surrogate) and HAV on five types of berries initially frozen at -20, -80 or -196 °C and stored at -20 °C for up to 24 months. MNV-1 titers decreased by up to 3.
View Article and Find Full Text PDFACS Appl Mater Interfaces
August 2025
Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry and Catalysis Research Center, Chair of Technical Electrochemistry, Lichtenbergstr. 4, 85748 Garching b. München, Germany.
The long-term stability of proton exchange membrane fuel cells (PEMFCs) faces significant challenges, particularly during start-up and shut-down events, which lead to degradation of the cathode catalyst through the oxidation of its carbon support. To improve catalyst durability, an anode catalyst with a high selectivity toward the hydrogen oxidation/evolution reaction rather than the oxygen reduction reaction is necessary. Pt/TiO/C ( < 2) catalysts have been reported to provide excellent hydrogen selectivity due to its strong metal-support interaction (SMSI) between Pt particles and TiO support.
View Article and Find Full Text PDFMicromachines (Basel)
August 2025
School of Mechanical and Electrical Engineering, Henan University of Technology, Zhengzhou 450001, China.
Single-crystal 4H silicon carbide (4H-SiC) is a key substrate material for third-generation semiconductor devices, where surface and subsurface integrity critically affect performance and reliability. This study systematically examined the evolution of surface morphology and subsurface damage (SSD) during nanoscratching of 4H-SiC under varying normal loads (0-100 mN) using a nanoindenter equipped with a diamond Berkovich tip. Scratch characteristics were assessed using scanning electron microscopy (SEM), while cross-sectional SSD was characterised via focused ion beam (FIB) slicing and transmission electron microscopy (TEM).
View Article and Find Full Text PDFMaterials (Basel)
August 2025
Department of Architecture, Faculty of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino Wakamatsu, Kitakyushu, Fukuoka 8080135, Japan.
The mitigation of early-age shrinkage and thermal cracking remains a pressing challenge in mass concrete structures. This study introduces a novel temperature-control admixture (TCA), formulated with gel-forming inorganic compounds, designed to suppress internal temperature rise while improving the mechanical stability of fly ash concrete. Four concrete mixes with TCA dosages of 0, 0.
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