• Title/Summary/Keyword: Chemical energy

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High-Energy Proton Generation with High Energy Conversion Efficiency Driven by Ultrashort High-Intensity Ti:Sapphire Laser (극초단 고출력 티타늄 사파이어 레이저에 의한 높은 에너지 변환효율을 가지는 고에너지 양성자 발생)

  • Choe, Il-U;Yu, Tae-Jun;Seong, Jae-Hui;Kim, Hyeong-Taek;Jeong, Tae-Mun;Hong, Gyeong-Han;Kim, Jeong-Hun;No, Yeong-Cheol;Go, Do-Gyeong;Lee, Jong-Min;Sagisaka, Akito;Yogo, Akifumi;Orimo, Satoshi;Ogura, Koichi;Li, Zhong;Pirozhkov, Alexander;Daido, Hiroyuki;Oishi, Yuji;Nemoto, Koshichi;Nakamura, Shyu;Noda, Akira;Iwashita, Yoshihisa;Shirai, Toshiyuki
    • Proceedings of the Optical Society of Korea Conference
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    • 2006.07a
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    • pp.379-380
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    • 2006
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Analysis of Gas Emissions and Power Generation for Co-firing Ratios of NG, NH3, and H2 Based on NGCC (NGCC 기반 천연가스, 암모니아, 수소 혼소 발전 비율에 따른 CO2와 NOx 배출량 및 전력 생산량 분석)

  • Inhye Kim;Jeongjae Oh;Taesung Kim;Minsuk Im;Sunghyun Cho
    • Korean Chemical Engineering Research
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    • v.62 no.3
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    • pp.225-232
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    • 2024
  • The reduction of CO2 emissions in the energy production sector, which accounts for 86.8% of total greenhouse gas emissions, is important to achieve carbon-neutrality. At present, 60% of total power generation in South Korea is coal and natural gas. Replacing fossil fuel with renewable energy such as wind and solar has disadvantages of unstable energy supply and high costs. Therefore, this study was conducted through the co-firing of natural gas, ammonia and hydrogen utilizing the natural gas combined cycle process. The results demonstrated reduction in CO2 emissions and 34%~238% of the power production compared to using only natural gas. Case studies on mass fractions of natural gas, ammonia and hydrogen indicated that power production and NOx emissions were inversely proportional to the ammonia ratio and directly proportional to the hydrogen ratio. This study provides guidelines for the use of various fuel mixtures and economic analysis in co-firing power generation.

Morphology Controlled Cathode Catalyst Layer with AAO Template in Polymer Electrolyte Membrane Fuel Cells (AAO를 사용한 고분자전해질 연료전지의 공기극 촉매층 구조 제어)

  • Cho, Yoon-Hwan;Cho, Yong-Hun;Jung, Nam-Gee;Ahn, Min-Jeh;Kang, Yun-Sik;Chung, Dong-Young;Lim, Ju-Wan;Sung, Yung-Eun
    • Journal of the Korean Electrochemical Society
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    • v.15 no.2
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    • pp.109-114
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    • 2012
  • The cathode catalyst layer in polymer electrolyte membrane fuel cells (PEMFCs) was fabricated with anodic aluminum oxide (AAO) template and its structure was characterized with scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis. The SEM analysis showed that the catalyst layer was fabricated the Pt nanowire with uniform shape and size. The BET analysis showed that the volume of pores in range of 20-100 nm was enhanced by AAO template. The electrochemical properties with the membrane electrode assembly (MEA) were evaluated by current-voltage polarization measurements and electrochemical impedance spectroscopy. The results showed that the MEA with AAO template reduced the mass transfer resistance and improved the cell performance by approximately 25% through controlling the structure of catalyst layer.

Layered Nickel-Based Oxides on Partially Oxidized Metallic Copper Foils for Lithium Ion Batteries

  • Chung, Young-Hoon;Park, Sun-Ha;Kim, Hyun-Sik;Sung, Yung-Eun
    • Journal of Electrochemical Science and Technology
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    • v.2 no.4
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    • pp.204-210
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    • 2011
  • Thin film electrodes have been intensively studied for active materials and current collectors to enhance the electrochemical performance. Here, porous structures of nickel-based oxide films, consisting of nickel oxide and copper (II) oxide, which was derived from the copper substrate during the annealing process, were deposited on metallic copper foils. The half-cell tests revealed excellent capacity retention after $80^{th}$ charge/discharge cycles. Some films showed an excess of the theoretical capacity of nickel oxides, which mainly originate from partially oxidized copper substrates during annealing. These results exhibit that both a preparation method of an active materials and partially oxidized current collectors could be important roles to apply thin film electrodes.

Stretchable Carbon Nanotube Composite Clays with Electrical Enhancers for Thermoelectric Energy Harvesting E-Skin Patches

  • Tae Uk Nam;Ngoc Thanh Phuong Vo;Jun Su Kim;Min Woo Jeong;Kyu Ho Jung;Alifone Firadaus Nurwicaksono Adi;Jin Young Oh
    • Elastomers and Composites
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    • v.58 no.1
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    • pp.11-16
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    • 2023
  • Electronic skin (e-skin), devices that are mounted on or attached to human skin, have advanced in recent times. Yet, the development of a power supply for e-skin remains a challenge. A stretchable thermoelectric generator is a promising power supply for the e-skin patches. It is a safe and semi-permanent energy harvesting device that uses body heat for generating power. Carbon nanotube (CNT) clays are used in energy-harvesting e-skin patches. In this study, we report improved thermoelectric performance of CNT clays by using chemical doping and physical blending of thermoelectric enhancers. The n-type and p-type thermoelectric enhancers increase electrical conductivity, leading to increased power factors of the thermoelectric CNT clays. The blend of CNT clays and enhancers is intrinsically stretchable up to 50% while maintaining its thermoelectric property.