https://repository.kopri.re.kr/handle/201206/15773 2026-09-14T09:03:20Z https://repository.kopri.re.kr/handle/201206/16871 Title: Investigating anthropogenic and natural characteristics of atmosphere-ice sheet exchanges using the international deep ice coring network Authors: Han, Yeongcheol 2026-02-27T00:00:00Z https://repository.kopri.re.kr/handle/201206/16886 Title: 미량기체를 활용한 남극 해안 신규 천부시추 빙하코어 연령 측정 Authors: 안진호 2026-01-31T00:00:00Z https://repository.kopri.re.kr/handle/201206/16849 Title: 빅토리아랜드 빙하코어시료의 강설량복원을 통한 과거대기대순환 복원 Authors: 이정훈 2026-01-12T00:00:00Z https://repository.kopri.re.kr/handle/201206/16545 Title: Molecular Mechanisms of Gas？Ice Interfacial Transport: Size- and Charge-Dependent Fractionation during Bubble Close-off Authors: Yi, Yoo Soo; Han, Yeongcheol Abstract: Gas？ice interfacial transport phenomena are essential across diverse cryogenic environments, ranging from gas fractionation in polar glaciers to the preservation of cosmogenic noble gases on icy celestial bodies. Bubble close-off in polar glaciers is a compelling example of the complex gas？ice interactions that challenge the interpretation of paleoclimate records preserved in ice cores. While previous studies have provided valuable insights, the molecular mechanisms governing fractionation, especially those involving both geometric and electronic characteristics, remain incompletely understood. Here, using density functional theory (DFT) calculations, we determine effective permeation energy barriers (EP) for noble gases (He, Ne, Ar, Kr, and Xe) and molecular gases (N2, O2, and CO2) through a model ice layer. Our results reveal that noble gases largely follow a size-dependent trend, whereas molecular gases deviate from such a simple relationship due to more complex gas？ice interactions resulting from their anisotropic charge distribution. The exponential dependence of permeation rates on EP accounts for the observed nonlinear depletion phenomenon. He and Ne, with their smaller sizes and weaker surface adsorption, exhibit higher permeation rates and rapid depletion from closed-off bubbles. Conversely, larger noble gases and molecular gases are preferentially retained due to increased energy barriers. Notably, molecular gases show significantly lower permeation rates than Ne despite comparable effective cross-sectional sizes, owing to stronger adsorption affinity. Chemical hardness, a descriptor reflecting electronic properties, helps reconcile the fractionation patterns observed for both gas types, indicating that interfacial interactions, not molecular size alone, govern transport through ice layers. These findings provide insights into gas preservation in diverse cryogenic environments, which is essential for the fidelity of paleoclimate reconstruction and the rational design of materials for selective transport. Discrepancies with field observations underscore the role of structural heterogeneities, such as grain boundaries, suggesting that bubble close-off fractionation involves additional pathways beyond idealized lattice permeation. 2025-11-01T00:00:00Z