Publications by authors named "Jaecheol Choi"

Despite significant advancements in all-solid-state batteries (ASSBs), the reliance on thick solid electrolyte (SE) membranes hinders their commercial viability. Although the dry process using polytetrafluoroethylene (PTFE) binder is proposed for thin SE membranes, a comprehensive understanding of the correlation between PTFE fibrillation and SE membrane quality remains lacking. Here an important guidance is provided for producing durable SE membranes that can be reduced to sub-20-µm thickness by regulating the entanglement networks of PTFE.

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The conventional dosage form of Ethyol (amifostine), a sterile lyophilized powder, involves reconstituting it with 9.7 mL of sterile 0.9% sodium chloride in accordance with the United States Pharmacopeia specifications for intravenous infusion.

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All-solid-state batteries (ASBs) have been identified as a potential next-generation technology for safe energy storage. However, the current pellet form of solid electrolytes (SEs) exhibits low cell-level energy densities and mechanical brittleness, and this has hampered the commercialization of ASBs. In this work, we report on the development of an ultrathin SE membrane that can be reduced to a thickness of 31 μm with minimal thermal shrinkage at 140 °C, while exhibiting robust mechanical properties (tensile strength of 19.

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Problematic issues with electrically inert binders have been less serious in the conventional lithium-ion batteries by virtue of permeable liquid electrolytes (LEs) for ionic connection and/or carbonaceous additives for electronic connection in the electrodes. Contrary to electron-conductive binders used to maximize an active loading level, the development of ion-conductive binders has been lacking owing to the LE-filled electrode configuration. Herein, we represent a tactical strategy for improving the interfacial Li conduction in all-solid-state electrolyte-free graphite (EFG) electrodes where the solid electrolytes are entirely excluded, using lithium-substitution-modulated (LSM) binders.

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Ammonia (NH) is a globally important commodity for fertilizer production, but its synthesis by the Haber-Bosch process causes substantial emissions of carbon dioxide. Alternative, zero-carbon emission NH synthesis methods being explored include the promising electrochemical lithium-mediated nitrogen reduction reaction, which has nonetheless required sacrificial sources of protons. In this study, a phosphonium salt is introduced as a proton shuttle to help resolve this limitation.

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The oral disintegrating film (ODF) has advantages over suspension and tablet. These include convenience of administration, patient compliance, and accurate dosing. We evaluated the bioequivalence between the ODF and the meloxicam suspension by using a crossover design with a 3-week washout period.

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Ammonia is of emerging interest as a liquefied, renewable-energy-sourced energy carrier for global use in the future. Electrochemical reduction of N (NRR) is widely recognised as an alternative to the traditional Haber-Bosch production process for ammonia. However, though the challenges of NRR experiments have become better understood, the reported rates are often too low to be convincing that reduction of the highly unreactive N molecule has actually been achieved.

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Metformin hydrochloride (MFM) is often used as a controlled-release (CR) tablet to reduce dosing frequency. However, the MFM CR tablet contains significant amounts of excipients and the tablet size is also large. Dosing convenience and patient compliance can be increased by reducing the size of the CR tablets.

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Metal-N-C is a type of attractive electrocatalyst for efficient CO reduction to CO. Because of the ambiguity in their atomic structures, the active sites and catalytic mechanisms of the catalysts have remained under debate. Here, the effects of N and C hybrid coordination on the activity of Ni-N-C catalysts were investigated, combining theoretical and experimental methods.

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It has become apparent that renewable energy sources are plentiful in many, often remote, parts of the world, such that storing and transporting that energy has become the key challenge. For long-distance transportation by pipeline and bulk tanker, a liquid form of energy carrier is ideal, focusing attention on liquid hydrogen and ammonia. Development of high-activity and selectivity electrocatalyst materials to produce these energy carriers by reductive electrochemistry has therefore become an important area of research.

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The original version of this Article contained errors in the author affiliations. Affiliation 1 incorrectly read 'School of Chemical Engineering, University of New South Wales (UNSW), Sydney, NSW 2031, Australia' and affiliation 4 incorrectly read 'School of Engineering, RMIT University, Melbourne, VIC 3001, Australia.' This has now been corrected in both the PDF and HTML versions of the Article.

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Negative carbon emission technologies are critical for ensuring a future stable climate. However, the gaseous state of CO does render the indefinite storage of this greenhouse gas challenging. Herein, we created a liquid metal electrocatalyst that contains metallic elemental cerium nanoparticles, which facilitates the electrochemical reduction of CO to layered solid carbonaceous species, at a low onset potential of -310 mV vs CO/C.

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Polymeric binder distribution within electrodes is crucial to guarantee the electrochemical performance of lithium-ion batteries (LIBs) for their long-term use in applications such as electric vehicles and energy-storage systems. However, due to limited analytical tools, such analyses have not been conducted so far. Herein, the adhesion properties of LIB electrodes at different depths are measured using a surface and interfacial cutting analysis system (SAICAS).

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Tumor necrosis (TN) can lower responsiveness to chemotherapy and confer basic resistance to anti-cancer therapy. We investigated the association of TN with poor clinical features and outcome in diffuse large B cell lymphoma (DLBCL). We examined the presence or absence of TN in 476 DLBCL patients of who received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy.

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The efficient and selective catalytic reduction of CO2 is a highly promising process for both of the storage of renewable energy as well as the production of valuable chemical feedstocks. In this work, we show that the addition of an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, in an aprotic electrolyte containing a proton source and FeTPP, promotes the in situ formation of the [Fe(0) TPP](2-) homogeneous catalyst at a less negative potential, resulting in lower overpotentials for the CO2 reduction (670 mV) and increased kinetics of electron transfer. This co-catalysis exhibits high Faradaic efficiency for CO production (93 %) and turnover number (2 740 000 after 4 hour electrolysis), with a four-fold increase in turnover frequency (TOF) when compared with the standard system without the ionic liquid.

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Although splenomegaly is major characteristic of primary myelofibrosis (PMF), splenomegaly has been devalued due to a less reliable method based on physical examination (PEx). We evaluated whether spleen volume (SV) on CT would accurately predict clinical outcomes in PMF. A total of 188 patients were enrolled.

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A highly adhesive and thermally stable copolyimide (P84) that is soluble in organic solvents is newly applied to silicon (Si) anodes for high energy density lithium-ion batteries. The Si anodes with the P84 binder deliver not only a little higher initial discharge capacity (2392 mAh g(-1)), but also fairly improved Coulombic efficiency (71.2%) compared with the Si anode using conventional polyvinylidene fluoride binder (2148 mAh g(-1) and 61.

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Background: DNA methyltransferase 3A (DNMT3A) mutation was recently introduced as a prognostic indicator in normal karyotype (NK) AML and we evaluated the incidence and prognostic impact of DNMT3A mutations in Korean NK AML patients.

Methods: Total 67 NK AML patients diagnosed during the recent 10 years were enrolled. DNMT3A mutations were analyzed by direct sequencing and categorized into nonsynonymous variations (NSV), deleterious mutations (DM), and R882 mutation based on in silico analysis results.

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The adhesion strength of lithium-ion battery (LIB) electrodes consisting of active material, a nanosized electric conductor, and a polymeric binder is measured with a new analysis tool, called the Surface and Interfacial Cutting Analysis System (SAICAS). Compared to the conventional peel test with the same electrode, SAICAS gives higher adhesion strength owing to its elaborate cutting-based measurement system. In addition, the effects on the adhesion property of the polymeric binder type and content, electrode density, and measuring point are also investigated to determine whether SAICAS provides reliable results.

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Mesoporous silicon nanofibers (m-SiNFs) have been fabricated using a simple and scalable method via electrospinning and reduction with magnesium. The prepared m-SiNFs have a unique structure in which clusters of the primary Si nanoparticles interconnect to form a secondary three-dimensional mesoporous structure. Although only a few nanosized primary Si particles lead to faster electronic and Li(+) ion diffusion compared to tens of nanosized Si, the secondary nanofiber structure (a few micrometers in length) results in the uniform distribution of the nanoparticles, allowing for the easy fabrication of electrodes.

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A colorimetric antifungal susceptibility test was performed using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride. Among 24 strains of Candida species, no trailing growth was found. In 22 and 20 strains, the MICs obtained in the colorimetric assay were within two dilutions of those obtained by the National Committee for Clinical Laboratory Standards method for ketoconazole and itraconazole, respectively.

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