Cellulosic pulp has been processed into insulation paper since the earliest days of electrical engineering. This polymer synthetized by nature has proved to be competitive to man-made plastics throughout the last century and is still widely used in electrical power transformers. The high working temperatures prevailing in such apparatuses and the desired lifespans of up to 40 years shifted the thermal stability of cellulose to the center of attention of many researchers. In this literature review, a summary of theories and recent insights regarding the processes upon thermal degradation of cellulose in the temperature range relevant for electrical power transformers is given, followed by an overview of strategies to improve the thermal stability of cellulosic insulators. Special emphasis is placed on the discussion of additives and modification agents and their action modes, and on the understanding how successful upgrading of cellulose towards high thermal stability is achieved.
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http://dx.doi.org/10.1016/j.carbpol.2020.117196 | DOI Listing |
Clin Oral Investig
January 2025
Department of Conservative Dentistry and Bucofacial Prostheses, Faculty of Odontology, Complutense University of Madrid, Madrid, Spain.
Objectives: This study aimed to assess the vertical misfit at the implant-abutment interface in external and internal connections across various implant brands, comparing original milled titanium abutments with laser-sintered cobalt-chromium (Co-Cr) abutments.
Materials And Methods: A total of 160 implants from four different brands were utilized, with 80 featuring external connections (EC) and 80 internal connections (IC). Original milled titanium abutments (n = 160) and Co-Cr laser-sintered abutments (n = 160) were randomly attached to each connection type, following the manufacturer's recommended torque.
Protein Sci
February 2025
Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.
The B domain of protein A is a biotechnologically important three-helix bundle protein. It binds the Fc fragment of antibodies with helix 1/2 and the Fab region with helix 2/3. Here we designed a helix shuffled variant by changing the connectivity of the helices, in order to redesign the helix bundle, yielding altered helix-loop-helix properties.
View Article and Find Full Text PDFProteins
January 2025
Institute of Molecular Biosciences, University of Graz, Graz, Austria.
The Old Yellow Enzyme from Ferrovum sp. JA12 (FOYE) displays an unusual thermal stability for an enzyme isolated from a mesophilic organism. We determined the crystal structure of this enzyme and performed bioinformatic characterization to get insights into its thermal stability.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Chemistry and Centre for Processable Electronics, Imperial College London, London, W12 0BZ, UK.
Most current highly efficient organic solar cells utilize small molecules like Y6 and its derivatives as electron acceptors in the photoactive layer. In this work, a small molecule acceptor, SC8-IT4F, is developed through outer side chain engineering on the terminal thiophene of a conjugated 6,12-dihydro-dithienoindeno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IDTT) central core. Compared to the reference molecule C8-IT4F, which lacks outer side chains, SC8-IT4F displays notable differences in molecule geometry (as shown by simulations), thermal behavior, single-crystal packing, and film morphology.
View Article and Find Full Text PDFChemistry
January 2025
Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India.
Chlorinated polymers have made enormous contributions to materials science and are commercially produced on a large scale. These chlorinated polymers could be recycled as chlorine sources to efficiently produce valuable chlorinated compounds owing to their facile release of HCl. Although the thermal stability of PVDC is low compared to PVC, this can be advantageous in terms of easy and fast dehydrochlorination.
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