To synthesize well-defined poly (α-amino acid)s (PAAs), ring opening polymerizations (ROP) of cyclic monomers of α-amino acid -carboxyanhydrides (NCAs) and -thiocarboxyanhydrides (NTAs) are most widely used. In this mini-review, we summarize the mechanism details of the monomer preparation and ROP. The present study used density functional theory calculations to reveal the mechanisms together with experimental phenomena in the past decades. Detailed discussion includes normal amine mechanism and the selectivity of the initiators bearing various nucleophilic groups.
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http://dx.doi.org/10.3389/fchem.2021.645949 | DOI Listing |
J Strength Cond Res
December 2024
Department of Human Performance and Health Education, Western Michigan University, Kalamazoo, Michigan.
Garner, C, Nachtegall, A, Roth, E, Sterenberg, A, Kim, D, Michael, T, and Lee, S. Effects of movement sonification auditory feedback on repetitions and brain activity during the bench press. J Strength Cond Res 38(12): 2022-2028, 2024-Auditory stimulation and feedback have been found to enhance aspects of motor performance such as motor learning, sense of agency, and movement execution.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
Architecting Prussian blue analogue (PBA) cathodes with optimized synergistic bimetallic reaction centers is a paradigmatic strategy for devising high-energy sodium-ion batteries (SIBs); however, these cathodes usually suffer from fast capacity fading and sluggish reaction kinetics. To alleviate the above problems, herein, a series of early transition metal (ETM)-late transition metal (LTM)-based PBA (Fe-VO, Fe-TiO, Fe-ZrO, Co-VO, and Fe-Co-VO) cathode materials have been conveniently fabricated via an "acid-assisted synthesis" strategy. As a paradigm, the FeVO-PBA (FV) delivers a superb rate capability (148.
View Article and Find Full Text PDFLangmuir
January 2025
Centre for Energy (M473), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
The mechanisms of NO reduction by CO over nitrogen-doped graphene (N-graphene)-supported single-atom Ni catalysts in the presence of O, HO, CO, and SO have been studied via density functional theory (DFT) modeling. The catalyst is represented by a single Ni atom bonded to four N atoms on N-graphene. Several alternative reaction pathways, including adsorption of NO on the Ni site, direct reduction of NO by CO, decomposition of NO to NO followed by reduction of NO to N, formation of active oxygen radical O*, and reduction of O* by CO, were hypothesized and the energy barrier corresponding to each of the reaction steps was calculated using DFT.
View Article and Find Full Text PDFChemphyschem
January 2025
Durgapur Government College, Department of Chemistry, INDIA.
The relative reactivity and cis/trans selectivity of the intramolecular [3+2] cycloaddition (IM32CA) reactions of nitrile oxide (NO), azide (AZ), nitrile sulfide (NS) and nitrile ylide (NY), leading to functionalized heterocycles are studied within the Molecular Electron Density Theory. The kinetically controlled IM32CA reactions are predicted to be cis stereospecific, while the reaction feasibility follows the order NY > NS > NO > AZ with the respective activation Gibbs free energies of 13.7, 17.
View Article and Find Full Text PDFNano Lett
January 2025
Department of Mechanical Engineering & Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States.
The development of accurate methods for determining how alloy surfaces spontaneously restructure under reactive and corrosive environments is a key, long-standing, grand challenge in materials science. Using machine learning-accelerated density functional theory and rare-event methods, in conjunction with environmental transmission electron microscopy (ETEM), we examine the interplay between surface reconstructions and preferential segregation tendencies of CuNi(100) surfaces under oxidation conditions. Our modeling approach predicts that oxygen-induced Ni segregation in CuNi alloys favors Cu(100)-O c(2 × 2) reconstruction and destabilizes the Cu(100)-O (2√2 × √2)45° missing row reconstruction (MRR).
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