Publications by authors named "JaeWoon Lee"

The use of elemental doping in lithium cobalt oxide (LCO) cathode material at high cutoff voltage is a widely adopted technique in the field of rechargeable batteries to mitigate multiple unfavorable phase transitions. However, there is still a lack of fundamental understanding regarding the rationality of each doping element implemented in this method, specifically considering the various thermodynamic stability and phase transitions. Herein, we investigated the effect of Ti doping on an O2 phase LCO (LCTO) cathode material that exhibited enhanced rate performance.

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In this article, the development of fluorescent imaging probes for the detection of Alzheimer's disease (AD)-associated protein aggregates is described. Indane derivatives with a donor-π-acceptor (D-π-A) structure were designed and synthesized. The probes were evaluated for their ability to bind to β-amyloid (Aβ) protein aggregates, which are a key pathological hallmark of AD.

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An intriguing mechanism for enabling fast Na kinetics during oxygen redox (OR) is proposed to produce high-power-density cathodes for sodium-ion batteries (SIBs) based on the P2-type oxide models, Na [Mn Ni ]O (NMNO) and Na [Ti Mn Ni ]O (NTMNO) using the "potential pillar" effect. The critical structural parameter of NTMNO lowers the Na migration barrier in the desodiated state because the electrostatic repulsion of O(2p)O(2p) that occurs between transition metal layers is combined with the chemically stiff Ti (3d)O(2p) bond to locally retain the strong repulsion effect. The NTMNO interlayer distance moderately decreases upon charging with oxygen oxidation, whereas that of NMNO decreases at a much faster rate, which can be explained by the dependence of OR activity on the coordination environment.

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Covalent surface modification of silica nanoparticles (SNPs) offers great potential for the development of multimodal nanomaterials for biomedical applications. Herein, we report the synthesis of covalently conjugated bifunctional SNPs and their application to multimodal imaging. Bis(methallyl)silane 15 with cyclopropene and maleimide, designed as a stable bifunctional linker, was efficiently synthesized by traceless Staudiger ligation, and subsequently introduced onto the surface of monodispersed SNPs Sc(OTf)-catalyzed siloxane formation.

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Oxygen redox (OR) reactions in sodium layered oxide cathodes have been studied intensively to harness their full potential in achieving high energy density for sodium-ion batteries (SIBs). However, OR triggers a large hysteretic voltage during discharge after the first charge process for OR-based oxides, and its intrinsic origin is unclear. Therefore, in this study, an in-depth reinvestigation on the fundamentals of the reaction mechanism in Na[LiMn]O with a Mn/Li ratio () of 2 was performed to determine the factors that polarize the OR activity and to provide design rules leading to nonhysteretic oxygen capacity using first-principles calculations.

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Background: Frontline healthcare workers responding to coronavirus disease 2019 (COVID-19) inevitably face tremendous psychological burden. Thus, the present study aimed to identify the psychological impact and the factors contributing to the likely increase in emotional distress of healthcare workers.

Methods: The participants include a total of 99 healthcare workers at Bugok National Hospital.

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An intriguing redox chemistry via oxygen has emerged to achieve high-energy-density cathodes and has been intensively studied for practical use of anion-utilization oxides in A-ion batteries (A: Li or Na). However, in general, the oxygen redox disappears in the subsequent discharge with a large voltage hysteresis after the first charge process for A-excess layered oxides exhibiting anion redox. Unlike these hysteretic oxygen redox cathodes, the two Na-excess oxide models NaIrO and NaRuO unambiguously exhibit nonhysteretic oxygen capacities during the first cycle, with honeycomb-ordered superstructures.

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Automatic robot gripper system which involves the automated object recognition of work-in-process in production line is the key technology of the upcoming manufacturing facility achieving Industry 4.0. Automatic robot gripper enables the manufacturing system to be autonomous, self-recognized, and adaptable by using artificial intelligence of robot programming dealing with arbitrary shapes of work-in-processes.

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A new paradigm based on an anionic O/O redox reaction has been highlighted in high-energy density cathode materials for sodium-ion batteries, achieving a high voltage (∼4.2 V Na/Na) with a large anionic capacity during the first charge process. The structural variations during (de)intercalation are closely correlated with stable cyclability.

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The methylation of lysine residues of histones plays a pivotal role in the regulation of chromatin structure and gene expression. Here, we report two crystal structures of SET7/9, a histone methyltransferase (HMTase) that transfers methyl groups to Lys4 of histone H3, in complex with S-adenosyl-L-methionine (AdoMet) determined at 1.7 and 2.

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