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How Cellulose Elongates - a QM/MM Study of the Molecular Mechanism of Cellulose Polymerization in Bacterial CESA
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Cyanine-Incorporated Amorphous Polymeric Carbon Dots for Optical Reactive Oxygen Species Sensing
Reactive oxygen species (ROS) are common cellular oxidants that when overproduced by cellular stressors cause harm to cells. Detection of ROS is of utmost importance to understanding a wide variety of cellular function and toxicity mechanisms. Conventional ROS fluorescence assays involve using a single dye to visualize the ROS quantity. Herein, we describe ROS-sensitive, fluorescent-dye-incorporated carbon dots with dual fluorescence capabilities and good biocompatibility. Carbon dots (CDs) made of citric acid and urea were synthesized with incorporated cyanine-3-amine (Cy3), a bright red fluorescent dye, to create Cy3-CDs. Additionally, to get Cy3 into the ROS-sensitive form, this work demonstrated that Cy3 alone and Cy3 within carbon dots can be electrochemically reduced to their colorless ROS-sensitive form. Cy3, CDs, and Cy3-CDs are all responsive to additions of superoxide, leading to an increase in the fluorescence. Overall, this work examines how O 2 •– and additional oxidizers interact with CDs, Cy3, and Cy3-CDs, and molecular-level hypotheses are explored that will inform the design of future carbon dot-based ROS sensors.
Close Packing of Nitroxide Radicals in Stable Organic Radical Polymeric Materials
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Chemical Vapor Deposition of Thin, Conductive, and Fouling-Resistant Polymeric Films
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Curious Case of BiEDOT: MALDI-TOF Mass Spectrometry Reveals Unbalanced Monomer Incorporation with Direct (Hetero)arylation Polymerization
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Cu-Catalyzed Atom Transfer Radical Polymerization in the Presence of Liquid Metal Micro/Nanodroplets
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Dynamics of Polymerization and Gelation in Epoxy Nanocomposites via X-ray Photon Correlation Spectroscopy
The details of the curing process of epoxy resins are notoriously difficult to ascertain, hampering polymer matrix composite manufacturing. Here, the curing of a series of six epoxy resins containing dilute spherical nanoparticles was investigated via X-ray photon correlation spectroscopy (XPCS). The resin formulation was varied to achieve a range of crosslink densities and topologies. Prior to gelation, the viscosities obtained from XPCS agreed with bulk rheology. A clear dynamic transition was detected in all samples, where the q-scaling changes from approximately q2 .2 to q 1 , indicating a transition from sub-diffusive to ballistic-like nanoparticle motion. For the samples with a high crosslink density, this change was abrupt and coincided with gelation, and there was no evidence of crosslink heterogeneity. Chain entanglement played a role in the transition for samples with lower crosslink density. Finally, this work reveals the potential of XPCS to deliver new quantitative insights into the curing process of thermosetting resins.
Are RAFT and ATRP Universally Interchangeable Polymerization Methods in Network Formation?
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Anionic Ring-Opening Polymerizations of N -Sulfonylaziridines in Ionic Liquids
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Toward Sustainable Elastomers from the Grafting-Through Polymerization of Lactone-Containing Polyest
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User Guide to Ring-Opening Metathesis Polymerization of endo -Norbornene Monomers with Chelated Initiators
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