Search

Your search keyword '"Lee GA"' showing total 193 results
Start Over Author "Lee GA" Publisher elsevier b.v.
193 results on '"Lee GA"'

28. Effects of angiotensin receptor blocker at discharge in patients with heart failure with reduced ejection fraction: Korean Acute Heart Failure (KorAHF) registry

Author

Choi, Ki Hong, Lee, Ga Yeon, Choi, Jin-Oh, Jeon, Eun-Seok, Lee, Hae-Young, Cho, Hyun-Jai, Lee, Sang Eun, Kim, Min-Seok, Kim, Jae-Joong, Hwang, Kyung-Kuk, Chae, Shung Chull, Baek, Sang Hong, Kang, Seok-Min, Choi, Dong-Ju, Yoo, Byung-Su, Kim, Kye Hun, Park, Hyun-Young, Cho, Myeong-Chan, and Oh, Byung-Hee

Published
2018
Full Text
View/download PDF

46. Performance enhancement of a diffusion-type solar still: Wettability and flowability of condensation surface.

Author

Lee, Ga-Ram, Park, Chang-Dae, Lim, Hyuneui, Cho, Sung-Hoon, Choi, Seok-Min, and Lim, Byung-Ju

Subjects
*SOLAR stills, *CONDENSATION, *WETTING, *WATER purification, *CONTACT angle, *PRODUCTION increases
Abstract

Several studies have been conducted to enhance the production of solar stills. However, studies focusing on the augmentation of condensation are still insufficient compared with those focusing on production improvement by enhancing evaporation. This study evaluates the effect of contact and sliding angles of condensation surfaces, which are criteria for determining wettability and flowability on the production of solar stills. Single-effect diffusion solar still was fabricated, and glass specimens with various wettability properties were prepared as condensation plates of the still to compare the performances. Experiments were performed by changing the condensation plates of the solar still. Meanwhile, the condensation process and droplet forms were observed as a function of wettability. The experimental results showed that the production rate increased by 45% with a decrease in the sliding angle; it also increased as the surface became superhydrophilic or superhydrophobic, but the sliding angle was a better indicator. Therefore, the material to be used for the condensation surface should be selected based on the sliding angle preferentially. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

50. Assessment of internal short-circuit risks in overdischarged lithium batteries under various charging conditions.

Author

Lee, Ga-Eun, Min, Yu-Jeong, and Shin, Heon-Cheol

Subjects
*COPPER, *SHORT circuits, *STRAY currents, *SUBSTRATES (Materials science), *ANODES, *LITHIUM cells
Abstract

This study analyzes the internal short-circuit behavior of an overdischarged secondary lithium-ion cell (OD-cell) under subsequent charging conditions. The results revealed that Cu ions dissolved from the anode Cu substrate during overdischarge were initially deposited on the cathode, migrated back to the anode, and deposited there during subsequent charging. These Cu deposits on the anode maintained their shape throughout normal charge–discharge cycles. Post-charging destructive analysis of the OD-cells revealed that the morphology of the Cu deposits on the anode surface varied significantly with the charging current. Cu formed coarse spherical particles at low currents (< 0.2 C-rate). As the current increased, a mixture of spherical and dendritic structures appeared. Only dendritic structures were observed above a certain threshold (> 3 C-rate). The leakage currents in OD-cells charged at various rates were measured to calculate their internal short-circuit resistance (ISR), and the relationship between Cu morphology and self-discharge was investigated. The "ISR decrease rate" was defined to compare the calculated ISR with the ISR of a normal cell, which was used as an indicator of the internal short circuit of the cell. The OD-cells charged at low currents (< 0.2 C-rate) maintained an ISR similar to that of normal cells (ISR decrease rate < 10%) with minimal self-discharge. However, high-current charging (> 3 C-rate) significantly reduced the ISR (decrease rate of > 97%) and introduced severe self-discharge. These findings suggest that high-rate charging immediately after overdischarge may exacerbate the internal short circuit and self-discharge owing to Cu-bridge formation. [ABSTRACT FROM AUTHOR]

Published
2025
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results