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Carbonyl fluoride (COF2) has gained interest as a low-GWP replacement candidate for the high-GWP fluorinated gases employed in semiconductor and display manufacturing. In this study, the infrared absorption cross-section of COF2 was experimentally measured using Fourier Transform Infrared (FTIR) spectroscopy, and its radiative efficiency was determined to be 0.119 W m−2 ppb−1 using the stratospheric-adjusted Pinnock curve. Atmospheric e-folding lifetimes derived from exponential decay measurements were 7.56 h in dry O2 and 54.86 and 36.67 min under low- and high-humidity ambient air, respectively. Incorporation of these lifetimes into the absolute GWP framework yielded GWP100 values of 4.05×10-4 (dry air), 6.82×10-6 (low humidity), and 3.16×10-6 (high humidity), demonstrating that rapid hydrolysis in the presence of water vapor suppresses the climate impact of COF2 to effectively zero under typical tropospheric conditions. Because CO2 is the terminal atmospheric degradation product, the long-term climate impact of COF2 emissions is equivalent to releasing only the stoichiometrically corresponding amount of CO2. These findings provide a fully experimental basis for determining the GWP100 of COF2 under atmospherically relevant conditions and demonstrate that its GWP100 is effectively near zero. This experimentally validated assessment confirms that COF2 is a viable low-GWP replacement gas for chamber-cleaning applications in semiconductor and display manufacturing.

The hard X-ray free-electron laser at the Pohang Accelerator Laboratory (PAL-XFEL) in the Republic of Korea achieved saturation of a 0.144 nm free-electron laser beam on 27 November 2016, making it the third hard X-ray free-electron laser in the world, following the demonstrations of the Linac Coherent Light Source (LCLS) and the SPring-8 Angstrom Compact Free Electron Laser (SACLA). The use of electron-beam-based alignment incorporating undulator radiation spectrum analysis has allowed reliable operation of PAL-XFEL with unprecedented temporal stability and dispersion-free orbits. In particular, a timing jitter of just 20 fs for the free-electron laser photon beam is consistently achieved due to the use of a state-of-the-art design of the electron linear accelerator and electron-beam-based alignment. The low timing jitter of the electron beam makes it possible to observe Bi(111) phonon dynamics without the need for timing-jitter correction, indicating that PAL-XFEL will be an extremely useful tool for hard X-ray time-resolved experiments. The Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) in South Korea has now entered operation with a timing jitter of just 20 fs.

This study reports the effects of changes in the waveform and frequency of radio frequency (RF) energy on the tissue ablation range. We developed a 70-watt RFA generator that provides sine and square waves and allows frequency control between 10 Hz and 500 kHz. The changes in the ablation range according to the waveform and frequency were observed using the developed generator. In the waveform variation test, the distance between the electrodes and the electrode type were changed for both waveforms with the frequency set to 500 kHz. In the frequency variation test, the waveform and electrode type were changed with the frequency set to 10, 100, and 500 kHz, while the distance between the electrodes was set to 20 mm. A fixed 45 voltage was applied using the bipolar method. RF energy was applied for 90 s in vitro. The temperature was regulated to not exceed 70°C. The ablation range was calculated using ImageJ software. The analysis results showed that the ablation range was larger with the square wave than with the sine wave and at 10 kHz than at 500 kHz. The developed generator can advance research on ablation area and depth in RF ablation.

The Korea Rare Isotope Accelerator, currently referred to as KoRIA, is briefly presented. The KoRIA facility is aimed to enable cutting-edge sciences in a wide range of fields. It consists of a 70 kW isotope separator on-line (ISOL) facility driven by a 70 MeV, 1 mA proton cyclotron and a 400 kW in-flight fragmentation (IFF) facility. The ISOL facility uses a superconducting (SC) linac for post-acceleration of rare isotopes up to about 18 MeV/u, while the SC linac of IFF facility is capable of accelerating uranium beams up to 200 MeV/u, 8 pμA and proton beams up to 600 MeV, 660 μA. Overall features of the KoRIA facility are presented with a focus on the accelerator design.

Owing to the advances in genome editing technologies, research on human pluripotent stem cells (hPSCs) have recently undergone breakthroughs that enable precise alteration of desired nucleotide bases in hPSCs for the creation of isogenic disease models or for autologous ex vivo cell therapy. As pathogenic variants largely consist of point mutations, precise substitution of mutated bases in hPSCs allows researchers study disease mechanisms with “disease-in-a-dish” and provide functionally repaired cells to patients for cell therapy. To this end, in addition to utilizing the conventional homologous directed repair system in the knock-in strategy based on endonuclease activity of Cas9 (i.e., ‘scissors’ like gene editing), diverse toolkits for editing the desirable bases (i.e., ‘pencils’ like gene editing) that avoid the accidental insertion and deletion (indel) mutations as well as large harmful deletions have been developed. In this review, we summarize the recent progress in genome editing methodologies and employment of hPSCs for future translational applications.

In a conventional two-dimensional (2D) culture method, cells are attached to the bottom of the culture dish and grow into a monolayer. These 2D culture methods are easy to handle, cost-effective, reproducible, and adaptable to growing many different types of cells. However, monolayer 2D cell culture conditions are far from those of natural tissue, indicating the need for a three-dimensional (3D) culture system. Various methods, such as hanging drop, scaffolds, hydrogels, microfluid systems, and bioreactor systems, have been utilized for 3D cell culture. Recently, external physical stimulation-based 3D cell culture platforms, such as acoustic and magnetic forces, were introduced. Acoustic waves can establish acoustic radiation force, which can induce suspended objects to gather in the pressure node region and aggregate to form clusters. Magnetic targeting consists of two components, a magnetically responsive carrier and a magnetic field gradient source. In a magnetic-based 3D cell culture platform, cells are aggregated by changing the magnetic force. Magnetic fields can manipulate cells through two different methods: positive magnetophoresis and negative magnetophoresis. Positive magnetophoresis is a way of imparting magnetic properties to cells by labeling them with magnetic nanoparticles. Negative magnetophoresis is a label-free principle-based method. 3D cell structures, such as spheroids, 3D network structures, and cell sheets, have been successfully fabricated using this acoustic and magnetic stimuli-based 3D cell culture platform. Additionally, fabricated 3D cell structures showed enhanced cell behavior, such as differentiation potential and tissue regeneration. Therefore, physical stimuli-based 3D cell culture platforms could be promising tools for tissue engineering.

An innovative continuous casting process named POCAST (POSCO’s advanced CASting Technology) was developed based on molten mold flux feeding technology to improve both the productivity and the surface quality of cast slabs. In this process, molten mold flux is fed into the casting mold to enhance the thermal insulation of the meniscus and, hence, the lubrication between the solidifying steel shell and the copper mold. Enhancement of both the castability and the surface quality of high-aluminum advanced high-strength steel (AHSS) slabs is one of the most important advantages when the new process has been applied into the commercial continuous casting process. A trial cast of TWIP steel has been carried out using a 10-ton scale pilot caster and 100-ton scale and 250-ton scale commercial casters. The amount of mold flux consumption was more than 0.2 kg/m 2 in the new process, which is much larger than that in the conventional powder casting. Trial TWIP castings at both the pilot and the plant caster showed stable mold performances such as mold heat transfer. Also, cast slabs showed periodic/sound oscillation marks and little defects. The successful casting of TWIP steel has been attributed to the following characteristics of POCAST: dilution of the reactant by increasing the slag pool depth, enlargement of channel for slag film infiltration at meniscus by elimination of the slag bear, and decrease of apparent viscosity of the mold slag at meniscus by increasing the slag temperature.

Oil/water (O/W) emulsions were prepared using the complex of quarternized cellulose nanofiber (QCNF) and octanoyl gelatin (OC−Gel) as an emulsifier, and the effect of pH value on their stability was investigated. OC−Gel was prepared through a condensation reaction, confirmed by 1H Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FT−IR) spectroscopy. It reduced air/water interfacial tension more effectively than unmodified gelatin. The complexation degree of OC−Gel and QCNF, measured by optical density, showed its maximum at a QCNF/OC−Gel mass ratio of 1/8 when the pH value of the medium was 7.4, and it increased in a saturated manner with increasing pH value. The signals of QCNF were found in the FT−IR and X−ray diffraction spectra of the complex, suggesting that the positively charged CNF were included in the OC−Gel−based complex. The complex formed a rough surface with smooth debris because the surface roughness of the complex aggregation reflected that of both QCNF and OC−Gel aggregation. QCNF could stabilize oil droplets to form a Pickering O/W emulsion. The complex of QCNF/OC−Gel was also a good emulsifier. QCNF and the complex were as potent as OC−Gel in emulsifying mineral oil in water. Most of the droplets fell within 5–25 µm, regardless of what the emulsifier was. The emulsion stabilized with OC−Gel increased in its oil droplet size more than two times in 20 days at all the pH vales tested (pH 3, 5, 7.4, 9), whereas the emulsion stabilized with QCNF remained almost constant in size during the same period regardless of the pH values. The droplet size of emulsion stabilized with the QCNF/OC−Gel complex did not change appreciably when the pH value was 5, 7.4, and 9. The complex seemed to act as a capsule wall and prevent the coalescence of the droplets. However, it increased dramatically due to the coalescence at pH 3, possibly because the complex could be dissolved under a strong acidic condition.

Implantation of ex vivo expanded and osteogenically differentiated mesenchymal stem cells (MSCs) for bone regeneration has drawbacks for clinical applications, such as poor survival of implanted cells and increased treatment expenses. As a new approach for bone regeneration that can circumvent these limitations, we propose dual delivery of substance P (SP) and bone morphogenetic protein-2 (BMP-2) to facilitate endogenous stem cell recruitment to bone defects by SP and subsequent in situ osteogenic differentiation of those cells by BMP-2. A heparin-conjugated fibrin (HCF) gel enabled dual delivery with fast release of SP and slow release of BMP-2, which would be ideal for prompt recruitment of endogenous stem cells in the first stage and time-consuming osteogenic differentiation of the recruited stem cells in the second stage. The HCF gels with SP and/or BMP-2 were implanted into mouse calvarial defects for 8 weeks. Local delivery of SP to the calvarial defects using HCF gel was more effective in recruiting MSCs to the calvarial defects than intraperitoneal or intravenous administration of SP. Many of the cells recruited by SP underwent osteogenic differentiation through local delivery of BMP-2. The efficacy of in vivo bone regeneration was significantly higher in the SP/BMP-2 dual delivery group. The dual delivery of SP and BMP-2 using the HCF gel therefore has potential as an effective bone regeneration strategy.

This reports a dual‐functional approach in which Fe catalysts, initially employed for methane pyrolysis to generate COx‐free hydrogen, are directly repurposed as anode materials following in situ carbon deposition. During methane splitting, catalytic decomposition of CH₄ at 900 °C forms onion‐like graphitic carbon shells (≈280 layers) around Fe cores (≈50 nm), producing a structurally stable and electrically conductive Fe@C900 composite without post‐treatment. This carbon‐enriched catalyst demonstrates exceptional electrochemical behavior when transitioned into a battery context. Without any conductive additives, Fe@C900 delivers a reversible capacity of 380 mAh g⁻¹ with 98% retention over 1000 cycles at 1 C. Under a 5000 G magnetic field, spin alignment within the Fe cores triggers directional lithium‐ion migration, enhancing rate performance by 150%. Multimodal characterization reveals accelerated lithium kinetics, stable SEI evolution, and deep lithiation behavior. DFT calculations further confirm strong lithium adsorption (−24.14 eV) and low insertion barriers (−22.85 eV), validating the spin‐guided diffusion mechanism. This work introduces a new class of hydrogen‐derived ferromagnetic anodes, where the byproduct of a clean hydrogen process is re‐engineered into a high‐rate, conductor‐free lithium storage platform. By coupling hydrogen generation with energy storage through shared material intermediates, this strategy offers a scalable path to carbon‐efficient, magnetically enhanced battery systems. Upcycled Fe@C900 from methane pyrolysis delivers superior lithium storage performance. Conductor‐free Fe@C900 achieves 367 mAh g−¹ and 98% capacity retention over 1000 cycles at 1C. Expanded interlayer spacing and stable SEI architecture ensure long‐term electrochemical durability. The external magnetic field aligns Fe core spins, accelerating Li⁺ diffusion and charge‐transfer kinetics. DFT calculations reveal low insertion barriers and strong Li⁺ binding in spin‐active carbon shells.