A5100752295- Atmospheric chemistry and aerosols
- Advanced oxidation water treatment
- Atmospheric and Environmental Gas Dynamics
- Mercury impact and mitigation studies
- Atmospheric Ozone and Climate
- Marine and coastal ecosystems
- Advanced Photocatalysis Techniques
- Adsorption and biosorption for pollutant removal
- Methane Hydrates and Related Phenomena
- Toxic Organic Pollutants Impact
- Water Treatment and Disinfection
- Industrial Gas Emission Control
- Geology and Paleoclimatology Research
- Freezing and Crystallization Processes
- Phosphorus and nutrient management
- Transportation Planning and Optimization
- Ocean Acidification Effects and Responses
- Arsenic contamination and mitigation
- Environmental remediation with nanomaterials
- Atmospheric aerosols and clouds
- Isotope Analysis in Ecology
- Arctic and Antarctic ice dynamics
- Per- and polyfluoroalkyl substances research
- Fluoride Effects and Removal
- Railway Systems and Energy Efficiency
Korea Polar Research Institute
2016-2025
Korea Institute of Sport Science
2023-2025
Korea University of Science and Technology
2017-2024
Kobe City Medical Center General Hospital
2024
Kyung Hee University
2019-2023
Inha University
2014-2023
Korea National Sport University
2020
Seoul National University
2020
University of Science and Technology
2019-2020
Andong National University
2020
We present Si nanotubes prepared by reductive decomposition of a silicon precursor in an alumina template and etching. These show impressive results, which shows very high reversible charge capacity 3247 mA h/g with Coulombic efficiency 89%, also demonstrate superior retention even at 5C rate (=15 A/g). Furthermore, the Li-ion full cell consisting cathode LiCoO2 anode demonstrates 10 times higher than commercially available graphite after 200 cycles.
A new strategy (i.e., freezing) for the activation of IO4- degradation aqueous organic pollutants was developed and investigated. Although furfuryl alcohol (FFA) by negligible in water at 25 °C, it proceeded rapidly during freezing -20 °C. The rapid FFA should be ascribed to freeze concentration effect that provides a favorable site liquid brine) proton-coupled process concentrating IO4-, FFA, protons. maximum absorption wavelength cresol red (CR) changed from 434 nm (monoprotonated CR) 518...
Focusing on several message features that are prominent in antismoking campaign literature, this content-analytic study examines 934 video clips YouTube for the following characteristics: sensation value (MSV) and three types of appeal (threat, social humor). These four characteristics then linked to YouTube's interactive audience response mechanisms (number viewers, viewer ratings number comments) capture reach, preference engagement. The findings suggest following: (i) messages prevalent...
The redox transformation of trace elements is critically affected by properties the environmental media. While environmentally important chemical reactions in aquatic environments have been extensively studied, those ice phase studied only a few cases. In this work, chromium and arsenic species were selected as model inorganic oxyanion contaminants for study ice. We investigated (1) reduction hexavalent Cr(VI) (as chromate) organic acids (e.g., citric oxalic acid) (2) simultaneous removal...
Abstract. Since the start of industrial revolution, human activities have caused a rapid increase in atmospheric carbon dioxide (CO2) concentrations, which have, turn, had an impact on climate leading to global warming and ocean acidification. Various approaches been proposed reduce CO2. The Martin (or iron) hypothesis suggests that iron fertilization (OIF) could be effective method for stimulating oceanic sequestration through biological pump iron-limited, high-nutrient, low-chlorophyll...
The chemistry of reactive halogens in the polar atmosphere plays important roles ozone and mercury depletion events, oxidizing capacity, dimethylsulfide oxidation to form cloud-condensation nuclei. Among halogen species, sources emission mechanisms inorganic iodine compounds boundary layer remain unknown. Here, we demonstrate that production tri-iodide (I3–) via iodide oxidation, which is negligible aqueous solution, significantly accelerated frozen both presence absence solar irradiation....
The availability of iron has been thought to be a main limiting factor for the productivity phytoplankton and related with uptake atmospheric CO2 algal blooms in fresh sea waters. In this work, formation bioavailable (Fe(II)aq) from dissolution oxide particles was investigated ice phase under both UV visible light irradiation. photoreductive oxides proceeded slowly aqueous solution (pH 3.5) but significantly accelerated polycrystalline ice, subsequently releasing more ferrous upon thawing....
This study demonstrates that the production of reactive oxidizing species (e.g., hydroxyl radical (•OH)) during photolysis nitrite (NO2(-)) or nitrate (NO3(-)) leads to oxidative conversion arsenite (As(III)) arsenate (As(V)). While direct UV photolytic oxidation As(III) was absent, (20 200 μM) addition markedly accelerated under irradiation (λ > 295 nm), which implies a role NO2(-) as photosensitizer for oxidation. Nitrate-mediated photooxidation revealed an initial lag phase NO3(-) is...
Abstract Current chemistry climate models do not include polar emissions and of halogens. This work presents the first implementation an interactive module into very short‐lived (VSL) halogen version Community Atmosphere Model with Chemistry (CAM‐Chem) model. The includes photochemical release molecular bromine, chlorine, interhalogens from sea‐ice surface, brine diffusion iodine biologically produced underneath within porous sea‐ice. It also heterogeneous recycling inorganic reservoirs...
Developing an optimal train speed profile for energy-efficient operation is significant in both theory and applications but very difficult complex to achieve. An optimization method that minimizes energy consumption by considering track alignment, limit, schedule adherence proposed. The objective function total consumption, the decision variables include timing of motion regimes. A simulated annealing algorithm (SA) developed search or "golden run." model applied a segment New Haven line...
The reductive transformation of Cr(VI) to Cr(III) by H2O2 in ice was compared with that water. reduction significant at −20 °C (ice), whereas the efficiency very low 25 (water). This enhanced observed over a wide range concentration (20–1000 μM), pH (3–11), and freezing temperature (−10 −30 °C). molar ratio consumed [H2O2] reduced [Cr(VI)] close agreement theoretical (stoichiometric) (1.5) for H2O2-mediated through proton-coupled electron transfer (PCET). synergistic increase water...
Dissolution of iron from mineral dust particles greatly depends upon the type and amount copresent inorganic anions. In this study, we investigated roles sulfate, chloride, nitrate, perchlorate on dissolution maghemite lepidocrocite in ice under both dark UV irradiation compared results with those their aqueous counterparts. After 96 h reaction, total dissolved (pH 3 before freezing) was higher than that phase 3) by 6–28 times 10–20 irradiation, respectively. Sulfuric acid most efficient...
Dimethyl sulfide (DMS) produced by marine algae represents the largest natural emission of sulfur to atmosphere. The oxidation DMS is a key process affecting new particle formation that contributes radiative forcing Earth. In this study, atmospheric and its major products (methanesulfonic acid, MSA; non-sea-salt sulfate, nss-SO42–) size distributions were measured at King Sejong station located in Antarctic Peninsula during austral spring–summer period 2018–2020. observatory was surrounded...
In this study, the toxicity of hexavalent chromium [Cr(VI)] reduced by citric acid in ice was measured using representative aquatic model invertebrates (i.e., rotifer, water flea, amphipod, and polychaete) a vertebrate (zebrafish) analyzing short- and/or long-term endpoints that are frequently applied to each animal. Cr(VI) reduction presence markedly enhanced phase compared an aqueous solution through freeze concentration effect. The highly concentrated grain boundaries were also confirmed...
Abstract. Iron dissolution from mineral dusts and soil particles is vital as a source of bioavailable iron in various environmental media. In this work, the oxide trapped ice was investigated new pathway supply. The experiments were carried out absence presence organic complexing ligands under dark condition. acidic pH conditions (pH 2, 3, 4), oxides greatly enhanced phase compared to that water. dissolved mainly ferric form, which indicates not reductive process. extent affected by kind...
A new mechanism for the abiotic production of molecular iodine (I2) from iodate (IO3–), which is most abundant species, in dark conditions was identified and investigated. The I2 aqueous solution containing IO3– nitrite (NO2–) at 25 °C negligible. However, redox chemical reaction between NO2– rapidly proceeded frozen −20 °C, resulted I2, I–, NO3–. rapid ascribed to accumulation IO3–, NO2–, protons liquid regions ice crystals during freezing (freeze concentration effect). This freeze effect...