166 results match your criteria: "Sungkyunkwan University Suwon[Affiliation]"

The synthesis of γ-chiral borylalkanes through copper-catalyzed enantioselective S2'-reduction of γ,γ-disubstituted allylic substrates and subsequent hydroboration was reported. A copper-DTBM-Segphos catalyst produced a range of γ-chiral alkylboronates from easily accessible allylic acetate or benzoate with high enantioselectivities up to 99% ee. Furthermore, selective organic transformations of the resulting γ-chiral alkylboronates generated the corresponding γ-chiral alcohol, arene and amine compounds.

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We report a novel strategy for the synthesis of Pt@Au nanorings possessing near-field focusing capabilities at the center through which single-particle surface enhanced Raman scattering could be readily observed. We utilized Pt@Au nanorings as a light-absorber; the absorbed light could be focused at the center with the aid of a Au nanoporous structure. We synthesized the Au nanolens structure through a Galvanic exchange process between Au ions and Ag block at the inner domain of the Pt@Au nanoring.

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Benzo[a]pyrene, classified as a Group 1 carcinogen, is metabolized to B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), causing DNA mutations and eventually cancer. Quercetin is a dietary flavonoid abundant in fruits and vegetables. After quercetin intake, quercetin's metabolites isorhamnetin and miquelianin are more highly concentrated than quercetin in the human plasma.

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The structure of microdroplet and microparticle is a critical factor in their functionality, which determines the distribution and sequence of physicochemical reactions. Therefore, the technology of precisely tailoring their shape is requisite for implementing the user demand functions in various applications. This review highlights various methodologies for droplet shaping, classified into passive and active approaches based on whether additional body forces are applied to droplets to manipulate their functions and fabricate them into microparticles.

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Cell reprogramming is considered a stochastic process, and it is not clear which cells are prone to be reprogrammed and whether a deterministic step exists. Here, asymmetric cell division (ACD) at the early stage of induced neuronal (iN) reprogramming is shown to play a deterministic role in generating elite cells for reprogramming. Within one day, fibroblasts underwent ACD, with one daughter cell being converted into an iN precursor and the other one remaining as a fibroblast.

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Extracellular vesicles (EVs) are essential mediators in intercellular communication that have emerged as natural therapeutic nanomedicines for the treatment of intractable diseases. Their therapeutic applications, however, have been limited by unpredictable in vivo biodistribution after systemic administration. To control the in vivo fate of EVs, their surfaces should be properly edited, depending on the target site of action.

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pH and redox dual-sensitive drug delivery system constructed based on fluorescent carbon dots.

RSC Adv

January 2021

MicroNano System Research Center, College of Information and Computer, Key Laboratory of Advanced Transducers and Intelligent Control System of the Ministry of Education and Shanxi Province, Taiyuan University of Technology Taiyuan 030024 China

Herein, a pH and redox dual-responsive drug delivery system (CDs-Pt(iv)-PEG) was developed based on fluorescence carbon dots (CDs). In this system, cisplatin(iv) prodrug (Pt(iv)) was selected as a model drug to reduce toxic side effects. The aldehyde-functionalized monomethoxy polyethylene glycol (mPEG-CHO) was conjugated to CDs-Pt(iv) to form pH sensitive benzoic imine bond.

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We discovered the efficient catalyst-free, photo-mediated oxidative cyclization reaction of bis--pyridinium benzoyl hydrazone (BH1) to 2-pyridinium-5-phenyl-1,3,4-oxadiazoles. This photoreaction is remarkable because it does not require additives (, bases, strong oxidants, or photocatalysts), which are essential in previous reports, and proceeds very effectively even with solid-state microporous organic polymers. Interestingly, we found that the inclusion complexation of BH1 with cucurbit[7]uril (CB7) interferes with the photo-induced electron transfer from BH1 to molecular oxygen through modification of the LUMO energy level, thus inhibiting the photo-medicated oxidative cyclization.

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The effect of magnetic flux pinning is investigated in GdBaCuO (GdBCO) thin films with two different types of ferromagnetic LaSrMnO (LSMO) buffers (nanoparticles and a layer) deposited on an STO substrate. Magnetization analyses reveal the presence of multiple flux pinning mechanisms responsible for the improvement in the critical current density of GdBCO films. While core pinning becomes a dominant pinning mechanism in GdBCO films with LSMO nanoparticles, a hybrid effect of magnetic-volume and core-point pinning is observed in GdBCO films with LSMO layers.

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Recently, combinations of 2D van der Waals (2D vdW) materials and organic materials have attracted attention because they facilitate the formation of various heterojunctions with excellent interface quality owing to the absence of dangling bonds on their surface. In this work, a double negative differential resistance (D-NDR) characteristic of a hybrid 2D vdW/organic tunneling device consisting of a hafnium disulfide/pentacene heterojunction and a 3D pentacene resistor is reported. This D-NDR phenomenon is achieved by precisely controlling an NDR peak voltage with the pentacene resistor and then integrating two distinct NDR devices in parallel.

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A series of quaternized polyphenylene oxide (QPPO) based alkaline electrolyte membranes with different degrees of quaternization were synthesized a benzyl bromination method at mild temperature (75 °C). Quite a high hydroxide conductivity under the reduced water uptake and swelling was exhibited by this method. When the degree of bromination measured from H NMR analysis was 30%, the corresponding hydroxide ion conductivity was 0.

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Etch characteristics of ovonic threshold switch (OTS) materials composed of Ge-As-Te for a phase-change random access memory (PCRAM) has been investigated using reactive ion etching hydrogen-based gases such as H, CH, NH, CH + H, and CH + NH. Among the investigated hydrogen-based gases, NH showed the highest etching rate of about 0.52 nm s, but the formation of nitride compounds and the increased roughness were observed on the OTS surface by nitrogen.

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To meet the growing demand for global electrical energy storage, high-energy-density electrode materials are required for Li-ion batteries. To overcome the limit of the theoretical energy density in conventional electrode materials based solely on the transition metal redox reaction, the oxygen redox reaction in electrode materials has become an essential component because it can further increase the energy density by providing additional available electrons. However, the increase in the contribution of the oxygen redox reaction in a material is still limited due to the lack of understanding its controlled parameters.

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Background Nonhyperemic pressure ratios (NHPRs) such as instantaneous wave-free ratio, resting full-cycle ratio, or diastolic pressure ratio have emerged as invasive physiologic indices precluding the need for hyperemic agents. The current study sought to evaluate the long-term prognostic implications of NHPRs compared with fractional flow reserve (FFR). Methods and Results NHPRs were calculated from resting pressure tracings by an independent core laboratory in 1024 vessels (435 patients).

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Using density functional theory, we investigate a novel two-dimensional silicon bismotide (SiBi) that has a layered GaSe-like crystal structure. molecular dynamic simulations and phonon dispersion calculations suggest its good thermal and dynamical stability. The SiBi monolayer is a semiconductor with a narrow indirect bandgap of 0.

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Bonding geometry engineering of metal-oxygen octahedra is a facile way of tailoring various functional properties of transition metal oxides. Several approaches, including epitaxial strain, thickness, and stoichiometry control, have been proposed to efficiently tune the rotation and tilt of the octahedra, but these approaches are inevitably accompanied by unnecessary structural modifications such as changes in thin-film lattice parameters. In this study, a method to selectively engineer the octahedral bonding geometries is proposed, while maintaining other parameters that might implicitly influence the functional properties.

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Herein, by using first-principles calculations, we demonstrate a two-dimensional (2D) of XSb (X = Si, Ge, and Sn) monolayers that have a honey-like crystal structure. The structural, mechanical, electronic, thermoelectric efficiency, and optical properties of XSb monolayers are studied. molecular dynamic simulations and phonon dispersion calculations suggests their good thermal and dynamical stabilities.

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Coral-like structured barium titanate (BaTiO) nanoparticles were synthesized as filler for a high dielectric elastomer. The nanoparticle size, and shape, and the reactivity of the synthesis were modified according to temperature, time, pH, and precursor materials. Dielectric properties of poly(dimethylsiloxane) (PDMS) composites were estimated by volume fractions of BaTiO of 5, 10, and 15 vol% for both sphere and coral-like shapes.

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L. is an annual herb belonging to the Asteraceae family. It is commonly grown in parts of Asia, including Korea and China, and is called by its nickname Gae-ddong-ssuk, or Chung-ho.

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In this work, by performing first-principles calculations, we explore the effects of various atom impurities on the electronic and magnetic properties of single layers of CN and CN. Our results indicate that atom doping may significantly modify the electronic properties. Surprisingly, doping Cr into a holey site of CN monolayer was found to exhibit a narrow band gap of 125 meV upon compression strain, considering the spin-orbit coupling effect.

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Understanding biointerfacial processes is crucial in various fields across fundamental and applied biology, but performing quantitative studies conventional characterization techniques remains challenging due to instrumentation as well as analytical complexities and limitations. In order to accelerate translational research and address current challenges in healthcare and medicine, there is an outstanding need to develop surface-sensitive technologies with advanced measurement capabilities. Along this line, nanoplasmonic sensing has emerged as a powerful tool to quantitatively study biointerfacial processes owing to its high spatial resolution at the nanoscale.

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A shingled module fabricated using electrically conductive adhesive (ECA) can increase the light-receiving area and provide greater power than a conventional module fabricated using solder-coated copper ribbons. However, several issues such as damage from laser cutting and poor contact by the conductive paste may arise. In this study, a 15.

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In this study, we synthesized and characterized two novel deep blue emitting materials based on indenoquinoline-substituted phenylanthracene derivatives. Multilayer organic light-emitting diodes were fabricated with the following sequence: indium-tin-oxide (ITO)/4,4',4″-tris[2-naphthyl(phenyl)amino (2-TNATA)/4,4'-bis(--naphthyl)--phenylamino) biphenyl (NPB)/Blue emitting material ( or )/Bathophenanthroline (Bphen)/lithium quinolate (Liq)/Al. A device using '7,7-dimethyl-9-(10-phenylanthracen-9-yl)-7H-indeno[1,2-f] isoquinoline ()' as an emitter showed the efficient emission with the luminous efficiency, power efficiency, and external quantum efficiency of 2.

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The ever-growing demand for high-energy lithium-ion batteries in portable electronics and electric vehicles has triggered intensive research efforts over the past decade. An efficient strategy to boost the energy and power density of lithium-ion batteries is to increase the Ni content in the cathode materials. However, a higher Ni content in the cathode materials gives rise to safety issues.

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