Application of Carbon Paper Layer for Polymer Membrane Fuel Cell Operation in Low Humidity Environment

황원찬,김성준,안치영,허민,김용민,조용훈,성영은 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Polymer electrolyte membrane fuel cell is an energy conversion system that converts chemical energy into electrical energy through an electrochemical reaction and has attracted attention for using a pollution-free energy source. Water management in fuel cells is an important factor in improving and maintaining performance. The lack of moisture in the polymer electrolyte membrane leads to problems such as reduced conductivity of hydrogen ions in the membrane and the catalyst layer. Therefore, a humidifier may be required for proper water management. However, additional humidifiers for humidification affect the system volume and weight increase. Therefore, it is important to improve the performance of fuel cells in low-humidity environments. In this study, we tried to apply carbon paper layer to MEA to operate in low-humidity environments.

Inhibition of phospholipase D2 induces autophagy in colorectal cancer cells

황원찬,김미경,송주현,최강열,민도식 생화학분자생물학회 2014 Experimental and molecular medicine Vol.46 No.-

Autophagy is a conserved lysosomal self-digestion process used for the breakdown of long-lived proteins and damaged organelles, and it is associated with a number of pathological processes, including cancer. Phospholipase D (PLD) isozymes are dysregulated in various cancers. Recently, we reported that PLD1 is a new regulator of autophagy and is a potential target for cancer therapy. Here, we investigated whether PLD2 is involved in the regulation of autophagy. A PLD2-specific inhibitor andsiRNA directed against PLD2 were used to treat HT29 and HCT116 colorectal cancer cells, and both inhibition and genetic knockdown of PLD2 in these cells significantly induced autophagy, as demonstrated by the visualization of light chain 3 (LC3)puncta and autophagic vacuoles as well as by determining the LC3-II protein level. Furthermore, PLD2 inhibition promoted autophagic flux via the canonical Atg5-, Atg7- and AMPK-Ulk1-mediated pathways. Taken together, these results suggest that PLD2 might have a role in autophagy and that its inhibition might provide a new therapeutic basis for targeting autophagy.

2P-479 A relatively simple method of forming pore structure in catalyst layer of polymer electrolyte membrane fuel cell

황원찬,안치영,김성준,허민,조용훈,성영은 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.0

Application of a hydrophilic carbon layer containing water for polymer membrane fuel cell for operation in low-humidity environment

황원찬,박성빈,성영은 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Water management is important in polymer electrolyte membrane fuel cells, which are emerging as pollution-free energy sources. Because the performance of polymer electrolyte membrane fuel cells depends on water management. The lack of moisture in the polymer electrolyte membrane leads to problems such as reduced conductivity of hydrogen ions in the membrane and the catalyst layer. When less than the appropriate moisture, the proton conductivity of membrane and ionomer decreases, resulting in a decrease in performance. Therefore, it is important to minimize the reduction in fuel cell performance even in low-humidity environments. In this study, we tried to apply hydrophilic carbon paper layer for gas diffusion layer to MEA that can hold the water to operate in low-humidity environments.

Effect of Porous Metal foam Structure as Flow Field in Polymer Electrolyte Membrane Fuel Cell

황원찬,박지은,성영은 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

In polymer electrolyte membrane fuel cells, mass transfer is a factor to consider to improve performance. In particular, the flow field of bipolar plates is an important factor for mass transfer, such as the supply of reactants and the removal of products. Various kind of porous materials have been studied as flow fields for improving mass transport and enhancing cell performance. Among them, metal foams have a three-dimensional pore structure and have advantages such as high porosity and good electrical conductivity. Copper foam is relatively inexpensive and can produce a variety of structures. In this study, the effects on copper foam structures such as thickness, area density, and pore size were identified.

Micro Channels for Humidification of Polymer Electrolyte Membrane Fuel Cells

황원찬,안치영,성영은 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Polymer electrolyte membrane fuel cells have attracted attention as energy conversion devices utilizing the use of pollution-free energy sources, oxygen (air) and hydrogen. In polymer electrolyte membrane fuel cells, water management is an important factor affecting performance. The lack of moisture in the polymer electrolyte membrane fuel cell causes problems such as a decrease in the conductivity of proton. Therefore, a humidification system is required to maintain sufficient proton conductivity for performance of fuel cell. In this study, an additional water supply channel is added to the separator plate of the fuel cell. Through this, it is possible to supply the moisture to the membrane and catalyst layer through the separator rather than the humidifying gas.

마태복음 12장 1-14절에 나타난 안식일 규례에 대한 마태 공동체와 유대교의 관계

황원찬(Won Chan Hwang) 한국Q학회 2018 예수말씀연구 Vol.12 No.-

마태 공동체와 유대교의 관계는 무엇인가? 학자들은 정반대의 의견을 가지고 이 질문에 대해서 대답을 주고 있다. 한편으로는, 마태공동체는 유대교로부터 독립된 이방인으로 구성된 그룹이라고 주장한다. 반면에, 마태공동체는 유대인 기독교 그룹이라고 주장된다. 양극의 입장들의 주장들은 모두 마태 공동체와 유대교의 관계를 해석하는데 중요한 역할을 한다. 그러나 이 모두 입장을 살펴보는 것은 이 논문에서 할 수 있는 범위를 벗어난다. 따라서 이 논문은 모세의 율법, 특히 안식일 규례에 대한 연구로 그 초점을 좁힌다. 이 논문은 마태 공동체와 바리새인들의 율법에 대한 해석의 차이를 다음과 같이 제안하고자 한다. 안식일 규례를 범할 수 있는 랍비들의 예외적인 허용은 오직 생명의 위협 가운데 있는 사람을 구하는 목적에만 제한을 두는 반면, 마태 공동체는 랍비들의 허용을 무제한적으로 넓혀서 랍비들이 허락할 수 없는 범위로까지 안식일 규례를 범하도록 허용한다. 그 근거로는 예수님은 그의 제자들이 안식일에 곡식의 이삭을 자르는 것을 합법화하며, 생명의 위협이 없는 마른 손을 가진 사람을 치료해주고, 마태 12장 11절에 있는 마태의 예수님의 말씀이 암시하듯이, 안식일에 구덩이에 빠진 한 동물을 끄집어내도록 허락한다. 이와 같은 마태의 예수님께서 보이신 행동과 안식일에 행해야 바른 행동에 관하여 하신 말씀은 안식일 규례에 대한 마태공동체의 입장을 드러내고, 더불어 안식일 규례에 대한 마태 공동체의 이해가 랍비들의 이해와 대치됨을 보여준다. The question of this dissertation is, what is the difference between the Matthean community and Judaism regarding the understanding of the Law? This question is set both in a broad range of the scholarly debate about whether Matthean community was an independent Gentile group from Judaism or was a Jewish Christian group and in a narrow range of the debate whether Matthean community abolished the law or distinctly interpreted it. To find some answer to this question, the dissertation choses the sabbath debates in Matthew 12:1-14. The two reasons for this are as follows: first, permitted or unpermitted actions of both Matthean community and the Pharisees on the sabbath and the Pharisees questions and Jesus answers provide better answer to the dissertation question than such abstract debates as relation between sentences and eschatological events at the end time (in 5:17-18); and, second, no scholar deals with the Pharisees question and Jesus answer (vv 10-11) which are the most important, to understand the difference between Matthean community and Judaism regarding the sabbath regulation. As method, the dissertation applies text, literary, and redaction criticisms to Matthew 12:1-14, and interprets this passage in the light of Jewish literatures, particularly rabbinic literatures and Qumran literatures. The two foundings are as follows: first, both Jewish halakhic characteristics (in vv 5-7) and Jesus entering the Synagogue and Pharisee s going out indicate that Matthean community stayed within Jewish community through participating in Jewish legal debates; second, Matthean community indiscriminately extends the rabbinic permistion with regard to violation of the sabbath regulations far beyond what the rabbi can permit (Mt 12:1, 11, 13).

1P-394 Application of metal foam on flow field of polymer electrolyte membrane fuel cell

박지은,황원찬,조용훈,성영은 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

Polymer-electrolyte-membrane fuel cells (PEMFCs) are attractive power sources for transportation applications. Unfortunately, the cell performance of PEMFCs is decreased due to three main losses: activation, ohmic, and mass transport loss. Among these losses, mass transport loss can be reduced by modifying the design of flow field in the bipolar plates. Metal foam, which is a three-dimensional porous material, can play a role in flow field because high porosity distributes reactants on entire area and removes efficiently generated water. In this work, we proposed various kinds of copper foam as flow field and optimized the structure of copper foam to achieve high cell performance. Single cell test, oxygen gain, and electrochemical impedance spectroscopy were evaluated to investigate the effect of copper foam on cell performance.

Regularly distributed cracks in fuel cell electrode for enhanced performance and durability

박성빈,황원찬,김성준,조용훈,성영은 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Polymer electrolyte fuel cells that use hydrogen and oxygen (air) as fuels are considered environmentally friendly devices because their by-products are heat and water. The research for improving the performance of such fuel cells has been progressed in various research groups. In this study, we tried to improve the fuel cell performance by introducing regular macropores into the fuel cell membrane-electrode assembly. The pores were prepared by simple mechanical post treatment on the prism patterned film to which the electrodes were applied. The membrane electrode assembly was inserted into a single-cell and subjected to electrochemical evaluation, and showed better performance than the conventional assembly.

Randomly distributed cracks in fuel cell electrode for enhanced performance and durability

박성빈,김성준,황원찬,조용훈,성영은 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Polymer electrolyte fuel cells are spotlighted as environmentally friendly power generation devices. This is the first study to introduce cracks into a fuel cell electrode, which are considered defects in a typical electrochemical energy conversion device. By introducing cracks in a simple mechanical method, the fuel cell's performance is increased and its durability is also improved. The morphologies of the cracks in the electrodes formed under various conditions was confirmed by scanning electron microscope, and the improved fuel cell characteristics were also confirmed through electrochemical evaluation.