55 results match your criteria: "Yonsei University Seoul 03722[Affiliation]"

Non-destructive color sensors are widely applied for rapid analysis of various biological and healthcare point-of-care applications. However, existing red, green, blue (RGB)-based color sensor systems, relying on the conversion to human-perceptible color spaces like hue, saturation, lightness (HSL), hue, saturation, value (HSV), as well as cyan, magenta, yellow, key (CMYK) and the CIE L*a*b* (CIELAB) exhibit limitations compared to spectroscopic methods. The integration of machine learning (ML) techniques presents an opportunity to enhance data analysis and interpretation, enabling insights discovery, prediction, process automation, and decision-making.

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Article Synopsis
  • - Metal halide perovskites are promising for optoelectronic applications but struggle with moisture sensitivity, which affects their performance and commercialization.
  • - Moisture causes degradation in these materials due to their ionic nature, making it challenging to fully understand how this impacts their luminescent properties.
  • - This study investigates the degradation of perovskite nanocrystals, finding that larger crystal sizes lead to improved stability in moist conditions, enhancing their optical performance and potential for light-emitting technologies.
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The selection of electrode material is a critical factor that determines the selectivity of electrochemical organic reactions. However, the fundamental principles governing this relationship are still largely unexplored. Herein, we demonstrate a photoelectrocatalytic (PEC) system as a promising reaction platform for the selective radical-radical coupling reaction owing to the inherent charge-transfer properties of photoelectrocatalysis.

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The impact of respiratory diseases is vast and multifaceted, affecting individuals, healthcare systems, and global economies. In response to the spread of respiratory pathogens, masks and respirators have become pivotal, demonstrating their capability to mitigate transmission. However, the limitations of conventional face masks or respirators, such as their single-use nature, environmental impact, and the risk of contact-based transmission, have accelerated the development of antimicrobial masks.

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  • Electrochemical production of hydrogen peroxide (HO) through a two-electron oxygen reduction reaction (2e ORR) is gaining interest for its sustainable and on-site benefits.
  • This study focuses on improving Ni-based catalysts, specifically designing atomically dispersed catalysts (Ni ADCs) to enhance HO production efficiency while addressing the low activity of traditional Ni catalysts.
  • Key findings indicate that using a coordinated precursor and controlled pyrolysis can create highly active Ni-N sites, which are crucial for achieving a record level of mass activity and selectivity in hydrogen peroxide synthesis.
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Accurate postoperative assessment of varying mechanical properties is crucial for customizing patient-specific treatments and optimizing rehabilitation strategies following Achilles tendon (AT) rupture and reconstruction surgery. This study introduces a wireless, chip-less, and immune-tolerant in vivo strain-sensing suture designed to continuously monitor mechanical stiffness variations in the reconstructed AT throughout the healing process. This innovative sensing suture integrates a standard medical suturing thread with a wireless fiber strain-sensing system, which incorporates a fiber strain sensor and a double-layered inductive coil for wireless readout.

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Two-dimensional radial-π-stacks in solution.

Chem Sci

April 2024

Department of Chemistry, College of Chemistry and Chemical Engineering, MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, Xiamen University Xiamen 361005 P. R. China.

Highly organized π-aggregate architectures can strongly affect electronic couplings, leading to important photophysical behaviors. With the escalating interest in two-dimensional (2D) materials attributed to their exceptional electronic and optical characteristics, there is growing anticipation that 2D radial-π-stacks built upon radial π-conjugation nanorings, incorporating intra- and inter-ring electronic couplings within the confines of a 2D plane, will exhibit superior topological attributes and distinct properties. Despite their immense potential, the design and synthesis of 2D π-stacks have proven to be a formidable challenge due to the insufficient π-π interactions necessary for stable stacking.

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The production of vanillin from biomass offers a sustainable route for synthesizing daily-use chemicals. However, achieving sunlight-driven vanillin synthesis through HO activation in an aqueous environment poses challenges due to the high barrier of HO dissociation. In this study, we have successfully developed an efficient approach for gram-scale vanillin synthesis in an aqueous reaction, employing Mn-defected γ-MnO as a photocatalyst at room temperature.

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Composites of reduced graphene oxides (rGOs) with transition metal dichalcogenides have garnered considerable attention as promising anode materials for sodium-ion batteries (SIBs) because of their superior theoretical capacity and long-term stability compared with pure graphene. However, the underlying mechanism of how the oxygen functional groups improve the functionality of rGO remains unclear. In this study, we investigated the roles of functional groups in rGO-based heterogeneous bilayers using first-principles density functional theory calculations.

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SnSe with its layered structure is a promising thermoelectric material with intrinsically low lattice thermal conductivity. However, its poor electronic transport properties have motivated extensive doping studies. Br doping effectively improves the power factor and converts the dimorphic SnSe to a fully hexagonal structure.

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The epidermal growth factor receptor (EGFR) is a cell-surface glycoprotein that is involved mainly in cell proliferation. Overexpression of this receptor is intimately related to the development of a broad spectrum of tumors. In addition, glycans linked to the EGFR are known to affect its EGF-induced activation.

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In the past decade, many approaches have been suggested to execute ML workloads on a DBMS. However, most of them have looked at in-DBMS ML from a training perspective, whereas ML inference has been largely overlooked. We think that this is an important gap to fill for two main reasons: (1) in the near future, every application will be infused with some sort of ML capability; (2) behind every web page, application, and enterprise there is a DBMS, whereby in-DBMS inference is an appealing solution both for efficiency (e.

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Understanding the characteristics of intrinsic defects in crystals is of great interest in many fields, from fundamental physics to applied materials science. Combined investigations of scanning tunneling microscopy/spectroscopy (STM/S) and density functional theory (DFT) are conducted to understand the nature of Se vacancy defects in monolayer (ML) ReSe grown on a graphene substrate. Among four possible Se vacancy sites, we identify the Se4 vacancy close to the Re layer by registry between STM topography and DFT simulated images.

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This study presents the development of a β-hairpin (tryptophan zipper, Trpzip)-based molecular tweezer (MT) that can control the folding and binding of α-helical peptides. When an α-helix isolated from the p53 protein was conjugated with Trpzip in an optimized macrocyclic structure, the folded β-hairpin stabilized the helix conformation through the side chain-to-side chain stapling strategy, which notably enhanced target (hDM2) affinity of the peptide. On the other hand, the helicity and binding affinity were significantly reduced when the hairpin was unfolded by a redox stimulus.

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Synthesis and Prospects of Holey Two-dimensional Platinum-group Metals in Electrocatalysis.

Angew Chem Int Ed Engl

December 2023

Center for Nanospace-confined Chemical Reactions (NCCR), Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea.

Advanced electrocatalysts can enable the widespread implementation of clean energy technologies. This paper reviews an emerging class of electrocatalytic materials comprising holey two-dimensional free-standing Pt-group metal (h-2D-PGM) nanosheets, which are categorically challenging to synthesize but inherently rich in all the qualities necessary to counter the kinetic and thermodynamic challenges of an electrochemical conversion process with high catalytic efficiency and stability. Although the 2D anisotropic growth of typical nonlayered metal crystals has succeeded and partly improved their atom-utilization efficiency, regularly distributed in-planar porosity can further optimize three critical factors that govern efficient electrocatalysis process: mass diffusion, electron transfer, and surface reactivity.

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We have successfully synthesized a novel form of polyglycerol with an unprecedentedly low degree of branching (DB = 0.08-0.18), eliminating the need for glycidol protection.

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Transition metal dichalcogenides (TMDs) are promising candidates for the semiconductor industry owing to their superior electrical properties. Their surface oxidation is of interest because their electrical properties can be easily modulated by an oxidized layer on top of them. Here, we demonstrate the XeF-mediated surface oxidation of 2H-MoTe (alpha phase MoTe).

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We describe fluorescent probes to detect formaldehyde (FA) in aqueous solutions and cells. The probes rapidly respond to FA in aqueous solutions and have great selectivity toward FA over other biologically relevant analytes. The results of cell studies reveal that probe 1 can be utilized to monitor endogenous and exogenous FA in live cells.

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In this study, we investigated the effect of phase-change characteristics on the device performance of carbon-incorporated GeSbTe (CGST) to understand the origin of the enhanced reliability and stabilization of the device. Macroscopic and microscopic measurements confirmed that the structural stability significantly increased with the incorporation of as much as 10% carbon. After the completion of bond formation between C and Ge, the excess C (>5 atomic%) engages in bonding with Sb in localized regions because of the difference in formation energy.

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Article Synopsis
  • The study introduces a wearable photodetector made from hybrid nanocomposites of carbon materials and biocompatible semiconductor nanocrystals (NCs), highlighting strong photoresponsivity and durability.
  • The research addresses the limitations of traditional heavy metal quantum dots, such as lead and cadmium, which are toxic and unsuitable for biomedical applications, by using silver sulfide (AgS) NCs and multi-walled carbon nanotubes (MWCNTs) instead.
  • A simple ultrasonic irradiation technique was used to fabricate the nanocomposite film without harmful chemicals, optimizing the size of AgS NCs to enhance both photo-response and mechanical durability for applications in near-infrared light detection.
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Lead-free halides with perovskite-related structures, such as the vacancy-ordered perovskite CsBiBr, are of interest for photovoltaic and optoelectronic applications. We find that addition of SnBr to the solution-phase synthesis of CsBiBr leads to substitution of up to 7% of the Bi(iii) ions by equal quantities of Sn(ii) and Sn(iv). The nature of the substitutional defects was studied by X-ray diffraction, Cs and Sn solid state NMR, X-ray photoelectron spectroscopy and density functional theory calculations.

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The regular ABX cubic perovskite structure is composed of close-packed AX layers stacked along the 〈111〉 axis. An equivalent hexagonal close-packed network can also be formed, in addition to a series of intermediate polytype sequences. Internally, these correspond to combinations of face- and corner-sharing octahedral chains that can dramatically alter the physical properties of the material.

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The tau protein is a highly soluble and natively unfolded protein. Under pathological conditions, tau undergoes multiple post-translational modifications (PTMs) and conformational changes to form insoluble filaments, which are the proteinaceous signatures of tauopathies. To dissect the crosstalk among tau PTMs during the aggregation process, we phosphorylated and ubiquitylated recombinant tau using GSK3β and CHIP, respectively.

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The development of synthetic routes to access stable, ultra-small ( <5 nm) lead halide perovskite (LHP) quantum dots (QDs) is of fundamental and technological interest. The considerable challenges include the high solubility of the ionic LHPs in polar solvents and aggregation to form larger particles. Here, we demonstrate a simple and effective host-guest strategy for preparing ultra-small lead bromide perovskite QDs through the use of nano-sized MOFs that function as nucleating and host sites.

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The recent advancements in multivalued logic gates represent a rapid paradigm shift in semiconductor technology toward a new era of hyper Moore's law. Particularly, the significant evolution of materials is guiding multivalued logic systems toward a breakthrough gradually, whereby they are transcending the limits of conventional binary logic systems in terms of all the essential figures of merit, i.e.

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