Hydrogen bonding and mechanical refining are closely correlated. In this work, structural variations of hydrogen bonding patterns in cellulose during mechanical pulp refining, including the hydrogen bonding energy and distance as well as the content of hydrogen bonds, have been explored by using the second derivative FTIR spectra and deconvolving spectra in the OH stretching vibrational region. Results show that except for the bond distance, both the hydrogen bonding energy and the content of hydrogen bonds exhibit a significant variation at an increasing beating degree. The calculated hydrogen bonding energies for intermolecular O6H⋯O3' decrease by 12.9%, while those of intramolecular O3H⋯O5 and O2H⋯O6 vary little. Evolutions of the content of certain hydrogen bonds differ depending on the different refining stage. It is suggested that along with the role of water, hydration and swelling, internal/external fibrillation and delamination are strongly related to the structural variations of hydrogen bonding patterns in cellulose during mechanical pulp refining.
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http://dx.doi.org/10.1016/j.carbpol.2018.10.024 | DOI Listing |
Sci Rep
December 2024
Geotechnical Institute, TU Bergakademie Freiberg, Freiberg, Germany.
The development of new urban areas necessitates building on increasingly scarce land, often overlaid on weak soil layers. Furthermore, climate change has exacerbated the extent of global arid lands, making it imperative to find sustainable soil stabilization and erosion mitigation methods. Thus, scientists have strived to find a plant-based biopolymer that favors several agricultural waste sources and provides high strength and durability for sustainable soil stabilization.
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December 2024
Department of Botany, The University of Burdwan, Purba Bardhaman, 713104, West Bengal, India.
The continuous exposure of chemical pesticides in agriculture, their contamination in soil and water pose serious threat to the environment. Current study used an approach to evaluate various pesticides like Hexaconazole, Mancozeb, Pretilachlor, Organophosphate and λ-cyhalothrin degradation capability of esterase. The enzyme was isolated from Salinicoccus roseus.
View Article and Find Full Text PDFJ Inorg Biochem
December 2024
Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina; Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina. Electronic address:
Here, we show that the replacement of the distal residues Asp and/or Arg of the DyP peroxidases from Bacillus subtilis and Pseudomonas putida results in functional enzymes, albeit with spectroscopically perturbed active sites. All the enzymes can be activated either by the addition of exogenous HO or by in situ electrochemical generation of the reactive oxygen species (ROS) OH, O and HO. The latter method leads to broader and upshifted pH-activity profiles.
View Article and Find Full Text PDFJ Phys Chem B
December 2024
Research Institute of Interdisciplinary Science & School of Materials Science and Engineering, Dongguan University of Technology, Dongguan 523808, China.
Peptide-based hydrogels form a kind of promising material broadly used in biomedicine and biotechnology. However, the correlation between their hydrogen bonding dynamics and mechanical properties remains uncertain. In this study, we found that the adoption of β-sheet and α-helix secondary structures by ECF-5 and GFF-5 peptides, respectively, could further form fiber networks to immobilize water molecules into hydrogels.
View Article and Find Full Text PDFGels
December 2024
Department of General Surgery, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing 211199, China.
Bacterial-infected skin wounds caused by trauma remain a significant challenge in modern medicine. Clinically, there is a growing demand for wound dressings with exceptional antibacterial activity and robust regenerative properties. To address the need, this study proposes a novel multifunctional dressing designed to combine efficient gas exchange, effective microbial barriers, and precise drug delivery capabilities, thereby promoting cell proliferation and accelerating wound healing.
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