Publications by authors named "Geonwoo Park"

We report the synthesis and characterization of an iron(III)-hydroperoxo complex generated from salicylate-assisted dioxygen activation by a cation-liganded iron(II) complex. Spectroscopic and theoretical data revealed stabilization of the end-on hydroperoxo ligand, and mechanistic insights, including a "V-shaped" Hammett plot, were confirmed by conducting oxygen atom transfer and proton-coupled electron transfer reactions.

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High-manganese steel (high-Mn) is valuable for its excellent mechanical properties in cryogenic environments, making it essential to understand its deformation behavior at extremely low temperatures. The deformation behavior of high-Mn steels at extremely low temperatures depends on the stacking fault energy (SFE) that can lead to the formation of deformation twins or transform to ε-martensite or α'-martensite as the temperature decreases. In this study, submerged arc welding (SAW) was applied to fabricate thick pipes for cryogenic industry applications, but it may cause problems such as an uneven distribution of manganese (Mn) and a large weldment.

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Controlling the formation of photoexcited triplet states is critical for many (photo)chemical and physical applications. Here, we demonstrate that a permanent out-of-plane distortion of the benzothioxanthene imide (BTI) dye promotes intersystem crossing by increasing spin-orbit coupling. This manipulation was achieved through a subtle chemical modification, specifically the bay-area methylation.

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A laser power bed fusion (L-PBF) manufacturing process was optimized by analyzing the surface morphology and track width of single scan tracks (SSTs) on Fe-3.4wt.%Si.

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Accurate hydrogen sulfide (HS) detection has attracted much attention because its toxicity may affect aquatic environments and human health. However, recognizing HS levels by conventional fluorescent probes in turbid wastewater has been challenging because the opaque environment interferes with their photophysical properties. To overcome this limitation, a fluorous-tagging strategy can be used for the development of fluorescent sensors to detect HS in turbid solutions.

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Interest in securing energy production channels from renewable sources is higher than ever due to the daily observation of the impacts of climate change. A key renewable energy harvesting strategy achieving carbon neutral cycles is artificial photosynthesis. Solar-to-fuel routes thus far relied on elaborately crafted semiconductors, undermining the cost-efficiency of the system.

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Marigold ( spp.) flower petals are the most vital sources of carotenoids, especially lutein esters, for the production of natural lutein to use for food, feed, and pharmaceutical industries. Several marigold cultivars are cultivated globally; however, their lutein ester composition and contents have not been widely investigated.

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Medial patellar luxation (MPL) is a common orthopedic disease in dogs, which predisposes elderly and small-breed dogs. Unlike in humans, diagnosis in the early course of the disease is challenging because symptoms and joint-pain expression in canines are vague. Herein, we introduced a deep-learning system to diagnose MPL using a single rear-view hindlimb image.

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The oxygen evolution reaction (OER) is a significant contributor to the cell overpotential in solid oxide electrolyzer cells (SOECs). Although noble metals such as Ru and Ir have been utilized as OER catalysts, their widespread application in SOECs is hindered by their high cost and limited availability. In this study, we present a highly effective approach to enhance air electrode performance and durability by depositing an ultrathin layer of metallic Ru, as thin as ∼7.

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Article Synopsis
  • Hyperactivated airway mucosa cells produce excess mucin, leading to severe breathing issues, and this study investigates the effects of saponins, particularly ginsenoside Rg5, on inflammation and mucin overproduction.
  • The study utilized NCI-H292 cells, treating them with various saponins and inducing mucin production with phorbol 12-myristate 13-acetate, measuring mucin levels and gene expression to assess the impact of Rg5.
  • Results showed that Rg5 significantly reduced mucin secretion and inflammation by modulating specific cellular pathways and promoting lipid droplet formation to clear reactive oxygen species, indicating its potential as a treatment for respiratory disorders linked to mucosa cell hyperactivation.
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Purpose: Of the 260,000 women diagnosed with breast cancer annually in the United States, more than 60% are treated with breast-conserving surgery or lumpectomy, followed by radiation to decrease the chance of local recurrence. More than 70% of breast cancer recurrences are localized to the original tumor cavity. Hence, targeted radiation therapy after lumpectomy is critical for recurrence prevention.

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This study investigated the mechanical properties of steel in flanges, with the goal of obtaining high strength and high toughness. Quenching was applied alone or in combination with tempering at one of nine combinations of three temperatures and durations . Cooling rates at various flange locations during quenching were first estimated using finite element method simulation, and the three locations were selected for mechanical testing in terms of cooling rate.

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