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Epoxy and phenolic resins are extensively used for modern microelectronics, for example, as packaging materials. Humidity may greatly alter or degrade their function and application, leading to failure of the device. A nonlinear optical laser technique, sum frequency generation (SFG) vibrational spectroscopy, was used to investigate the molecular surface structures of the epoxy and phenolic resins after exposure to humid air. It was found that the adsorbed water molecules at the phenolic resin surface can induce substantial surface restructuring. The surface phenyl groups were reoriented closer to a perpendicular position to the surface after exposure to humid air from a more parallel position in air. Epoxide group surface restructuring was not observed.
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http://dx.doi.org/10.1021/jp9058092 | DOI Listing |
Langmuir
September 2025
Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States.
Amphiphilic monolayers composed of end groups with distinct polar and nonpolar functional groups offer rapid and reversible interfacial adaptation in response to environmental stimuli such as a change in interfacial medium polarity. We have synthesized and characterized a suite of monolayers with functional groups of competing polarity designed to reconfigure their interfacial chemical composition in response to solvent polarity. In these films, the end group is designed to be able to reorient and expose the functional groups that minimize the interfacial free energy between the film and the environment.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, P. R. China.
Supported metal clusters have reactivities that depend on their nuclearity and structure. Herein, we present a strategy for precisely controlling the nuclearity of platinum clusters and demonstrate their size-dependent restructuring behavior and catalytic properties. The clusters are located on isolated CeO nanoislands on high-area SiO, and the isolation facilitates control of the migration of the platinum.
View Article and Find Full Text PDFThe brain is a metabolically demanding organ as it orchestrates and stabilizes neuronal network activity through plasticity. This mechanism imposes enormous and prolonged energetic demands at synapses, yet it is unclear how these needs are met in a sustained manner. Mitochondria serve as a local energy supply for dendritic spines, providing instant and sustained energy during synaptic plasticity.
View Article and Find Full Text PDFDiabetes
September 2025
Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA.
Unlabelled: Type 1 diabetes (T1D) is caused by the selective autoimmune ablation of pancreatic β-cells. Emerging evidence reveals β-cell secretory dysfunction arises early in T1D development and may contribute to diseases etiology; however, the underlying mechanisms are not well understood. Our data reveal that proinflammatory cytokines elicit a complex change in the β-cell's Golgi structure and function.
View Article and Find Full Text PDFSmall
September 2025
Institute of New Energy Materials, School of Materials Science and Engineering, Tianjin University, Tianjin, 300072, China.
Copper (Cu) catalysts with abundant defects are pivotal for converting CO into valuable multi-carbon products. However, the practical application of Cu catalysts is challenged by the thermodynamic instability of the defects, often leading to surface reconstruction during catalytic processes. Here, it is found that particle size and COO-containing intermediates are key factors driving reconstruction, as the defect stability is size-dependent and can be amplified by leveraging the highly reactive intermediates as the initial reactant.
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