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Highly substituted perfluoroacylated chitosan can alter the physicochemical properties of chitosan; however, the currently synthesized perfluoroacylated chitosan has a low degree of substitution. In this study, we present a simple method for the homogeneous preparation of highly substituted N-perfluoroacylated chitosan, conducted at room temperature without requiring strict anhydrous or oxygen-free conditions. Various perfluorocarbon chains were successfully attached to chitosan through a reaction between perfluorinated acid esters and amines, catalyzed by DBU. The synthesized N-perfluoroacylated chitosan, with high degree of substitution, demonstrated excellent solubility in common organic solvents. Comprehensive characterization was performed using elemental analysis, nuclear magnetic resonance (including two-dimensional NMR), gel permeation chromatography, infrared spectroscopy, X-ray diffraction, and thermal analysis. The resulting films exhibited high water contact angles. Notably, as the fluorocarbon chain length increased, tensile strength gradually decreased, while elongation at break improved. Additionally, water uptake, water vapor transmission rate, and oxygen transmission rate all exhibited a declining trend. The films exhibited good biocompatibility, and in the grape preservation experiment, HFBC treatment effectively delayed grape aging and deterioration while enhancing quality preservation. These results suggest that HFBC film holds promising potential for food packaging applications.
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http://dx.doi.org/10.1016/j.ijbiomac.2024.136716 | DOI Listing |
Front Sociol
August 2025
Laboratory of Anthropology of Contemporary Worlds (LAMC), Faculty of Philosophy and Social Sciences, Institute of Sociology, Université Libre de Bruxelles (ULB), Brussels, Belgium.
Contemporary debates about artificial intelligence (AI) still treat automation as a straightforward substitution of human labor by machines. Drawing on Goffman's dramaturgical sociology, this paper reframes AI in the workplace as rather than automation. We argue that the central-but routinely overlooked-terrain of struggle is symbolic-interactional: workers continuously stage, conceal, and re-negotiate what counts as "real" work and professional competence.
View Article and Find Full Text PDFTetrahedron
August 2024
Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, IL, 61801, USA.
A dearomative 1,4-hydroamination of nonactivated arenes has been developed, using a key arene-arenophile photocycloaddition strategy to disrupt aromaticity. Palladium catalysis with K-Selectride as a hydride source uniquely enables selective reactivity and provides access to a range of substituted 1,4-cyclohexadienes from aromatic starting materials. We demonstrate a few synthetic applications of this scalable procedure by preparing highly-functionalized small molecules in three to four steps from naphthalene.
View Article and Find Full Text PDFMater Today Bio
October 2025
Radboud University Medical Center, Research Institute for Medical Innovation, Department of Medical BioSciences, Geert Grooteplein 28, 6525 GA, Nijmegen, the Netherlands.
Severe scarring is an inevitable consequence of large full-thickness skin wounds, often leading to long-term complications that affect patients' well-being and necessitate extended medical interventions. While autologous split-thickness skin grafts remain the clinical standard for wound treatment, they frequently result in contractures, excessive scarring, and the need for additional corrective procedures. To address these challenges, bioengineered skin substitutes capable of promoting efficient healing while reducing complications are highly desirable.
View Article and Find Full Text PDFAnal Chim Acta
November 2025
Department of chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX, USA. Electronic address:
Background: Carbonate esters are polar aprotic solvents that can be used to replace polar solvents: methanol, acetonitrile, or even apolar solvents in the mobile phases for liquid chromatography. Dimethyl, diethyl, and propylene carbonates (DMC, DEC, and PC) are not fully soluble in water.
Results: Twelve volume phase diagrams of water, the three carbonates, and methanol, ethanol, propanol, and acetonitrile were determined.
Chemistry
September 2025
Department of Chemistry, Indian Institute of Technology Patna, Patna, Bihar, 801106, India.
In this work, we report the design, synthesis, and application of a hyper-crosslinked heterogeneous organometallic porous organic polymer (Pd@TP-DPPF) catalyst for the efficient and sustainable dicarbofunctionalization of internal alkynes via a facile three-component reaction. This strategy enables the highly trans-selective syntheses of tetrasubstituted olefins in excellent yields. The catalyst is constructed by integrating triptycene (TP) and 1,1'-bis(diphenylphosphino)ferrocene (DPPF) into a robust palladium-based porous framework, resulting in a unique heterogeneous system that efficiently mediates the coupling of internal alkynes with readily available iodoarenes and aryl/methyl boronic acids.
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