메뉴 건너뛰기




Volumn , Issue , 2008, Pages 547-607

Electrochemical methods for catalyst activity evaluation

Author keywords

[No Author keywords available]

Indexed keywords


EID: 84891978928     PISSN: None     EISSN: None     Source Type: Book    
DOI: 10.1007/978-1-84800-936-3_11     Document Type: Chapter
Times cited : (10)

References (66)
  • 3
    • 0029327090 scopus 로고
    • In situ membrane resistance measurements in polymer electrolyte fuel cells by fast auxiliary current pulses
    • Buchi FN, Marek A, Scherer GG. In situ membrane resistance measurements in polymer electrolyte fuel cells by fast auxiliary current pulses. J Electrochem Soc 1995;142:1895-901.
    • (1995) J Electrochem Soc , vol.142 , pp. 1895-1901
    • Buchi, F.N.1    Marek, A.2    Scherer, G.G.3
  • 4
    • 0038167451 scopus 로고    scopus 로고
    • Investigation of the transversal water profile in Nafion membranes in polymer electrolyte fuel cells
    • Buchi FN, Scherer GG. Investigation of the transversal water profile in Nafion membranes in polymer electrolyte fuel cells. J Electrochem Soc 2001;148:A183-8.
    • (2001) J Electrochem Soc , vol.148
    • Buchi, F.N.1    Scherer, G.G.2
  • 5
    • 0027709936 scopus 로고
    • AC impedance investigations of proton conduction in Nafion™
    • Cahan BD, Wainright JS. AC impedance investigations of proton conduction in Nafion™. J Electrochem Soc 1993;140:L185-6.
    • (1993) J Electrochem Soc , vol.140
    • Cahan, B.D.1    Wainright, J.S.2
  • 6
    • 33947598425 scopus 로고    scopus 로고
    • Electro-oxidation of methanol and formic acid on PtRu and PtAu for direct liquid fuel cells
    • Choi JH, Jeong KJ, Dong Y, Han J, Lim TH, Lee JS, et al. Electro-oxidation of methanol and formic acid on PtRu and PtAu for direct liquid fuel cells. J Power Sources 2006;163:71-5.
    • (2006) J Power Sources , vol.163 , pp. 71-75
    • Choi, J.H.1    Jeong, K.J.2    Dong, Y.3    Han, J.4    Lim, T.H.5    Lee, J.S.6
  • 7
    • 0033321385 scopus 로고    scopus 로고
    • 2/CO mixtures on Ptbased gas-diffusion electrodes
    • 2/CO mixtures on Ptbased gas-diffusion electrodes. J Electrochem Soc 1999;146:4031-40.
    • (1999) J Electrochem Soc , vol.146 , pp. 4031-4040
    • Ciureanu, M.1    Wang, H.2
  • 8
    • 0034511075 scopus 로고    scopus 로고
    • Carbon monoxide electro-oxidation properties of carbon-supported PtSn catalysts prepared using surface organometallic chemistry
    • Crabb EM, Marshall R, Thompsett D. Carbon monoxide electro-oxidation properties of carbon-supported PtSn catalysts prepared using surface organometallic chemistry. J Electrochem Soc 2000;147:4440-7.
    • (2000) J Electrochem Soc , vol.147 , pp. 4440-4447
    • Crabb, E.M.1    Marshall, R.2    Thompsett, D.3
  • 10
    • 27944444164 scopus 로고    scopus 로고
    • Instability of Pt/C electrocatalysts in proton exchange membrane fuel cells: A mechanistic investigation
    • Ferreira PJ, la O' GJ, Shao-Horn Y, Morgan D, Makharia R, Kocha S, et al. Instability of Pt/C electrocatalysts in proton exchange membrane fuel cells: a mechanistic investigation. J Electrochem Soc 2005;152:A2256-71.
    • (2005) J Electrochem Soc , vol.152
    • Ferreira, P.J.1    Lao, G.J.2    Shao-Horn, Y.3    Morgan, D.4    Makharia, R.5    Kocha, S.6
  • 12
    • 0039874843 scopus 로고
    • 2 evolution reaction at Pt in KOH solution
    • 2 evolution reaction at Pt in KOH solution. J Electroanal Chem 1995;395:261-71.
    • (1995) J Electroanal Chem , vol.395 , pp. 261-271
    • Gao, L.J.1    Conway, B.E.2
  • 13
    • 0024622682 scopus 로고
    • The effect of phosphoric acid concentration on electrocatalysis
    • Glass JT, Cahen GLJ, Stoner GE. The effect of phosphoric acid concentration on electrocatalysis. J Electrochem Soc 1989;136:656-60.
    • (1989) J Electrochem Soc , vol.136 , pp. 656-660
    • Glass, J.T.1    Glj, C.2    Stoner, G.E.3
  • 14
    • 0242677744 scopus 로고    scopus 로고
    • Study of ionic conductivity profiles of the air cathode of a PEMFC by AC impedance spectroscopy
    • Guo Q, Cayetano M, Tsou YM, De Castro ES, White RE. Study of ionic conductivity profiles of the air cathode of a PEMFC by AC impedance spectroscopy. J Electrochem Soc 2003;150:A1440-9.
    • (2003) J Electrochem Soc , vol.150
    • Guo, Q.1    Cayetano, M.2    Tsou, Y.M.3    De Castro, E.S.4    White, R.E.5
  • 15
    • 2042435765 scopus 로고    scopus 로고
    • A steady-state impedance model for a PEMFC cathode
    • Guo Q, White RE. A steady-state impedance model for a PEMFC cathode. J Electrochem Soc 2004;151:E133-49.
    • (2004) J Electrochem Soc , vol.151
    • Guo, Q.1    White, R.E.2
  • 16
    • 84916391128 scopus 로고
    • In situ FT-IR spectroscopic study of electrochemical adsorption of phosphoric acid on platinum
    • Habib MA, Bockris JOM. In situ FT-IR spectroscopic study of electrochemical adsorption of phosphoric acid on platinum. J Electrochem Soc 1983;130:2510-2.
    • (1983) J Electrochem Soc , vol.130 , pp. 2510-2512
    • Habib, M.A.1    Bockris, J.O.M.2
  • 17
    • 0036685666 scopus 로고    scopus 로고
    • An electrochemical method to improve the performance of air cathodes and methanol anodes
    • He C, Qi Z, Hollett M, Kaufman A. An electrochemical method to improve the performance of air cathodes and methanol anodes. Electrochem Solid-State Lett 2002;5:A181-3.
    • (2002) Electrochem Solid-State Lett , vol.5
    • He, C.1    Qi, Z.2    Hollett, M.3    Kaufman, A.4
  • 18
    • 27644537999 scopus 로고    scopus 로고
    • Platinum-iridium alloys as oxygen reduction electrocatalysts for polymer electrolyte fuel cells
    • Ioroi T, Yasuda K. Platinum-iridium alloys as oxygen reduction electrocatalysts for polymer electrolyte fuel cells. J Electrochem Soc 2005;152:A1917-24.
    • (2005) J Electrochem Soc , vol.152
    • Ioroi, T.1    Yasuda, K.2
  • 19
    • 0029360298 scopus 로고
    • Modeling of proton exchange membrane fuel cell performance with an empirical equation
    • Kim J, Lee SM, Srinivasan S. Modeling of proton exchange membrane fuel cell performance with an empirical equation. J Electrochem Soc 1995;142:2670-4.
    • (1995) J Electrochem Soc , vol.142 , pp. 2670-2674
    • Kim, J.1    Lee, S.M.2    Srinivasan, S.3
  • 20
    • 33646889980 scopus 로고    scopus 로고
    • Unusually active palladium-based catalysts for the electrooxidation of formic acid
    • Larsen R, Ha S, Zakzeski J, Masel RI. Unusually active palladium-based catalysts for the electrooxidation of formic acid. J Power Sources 2006;157:78-84.
    • (2006) J Power Sources , vol.157 , pp. 78-84
    • Larsen, R.1    Ha, S.2    Zakzeski, J.3    Masel, R.I.4
  • 22
    • 0037076742 scopus 로고    scopus 로고
    • Assessment of CO-tolerance for different Pt-alloy anode catalysts in a polymer electrolyte fuel cell using AC impedance spectroscopy
    • Leng YJ, Wang X, Hsing IM. Assessment of CO-tolerance for different Pt-alloy anode catalysts in a polymer electrolyte fuel cell using AC impedance spectroscopy. J Electroanal Chem 2002;528:145-52.
    • (2002) J Electroanal Chem , vol.528 , pp. 145-152
    • Leng, Y.J.1    Wang, X.2    Hsing, I.M.3
  • 23
    • 0242509207 scopus 로고    scopus 로고
    • Ionic conductivity of PEMFC electrodes: Effect of Nafion loading
    • Li G, Pickup PG. Ionic conductivity of PEMFC electrodes: effect of Nafion loading. J Electrochem Soc 150 2003;C745-52.
    • (2003) J Electrochem Soc , vol.150
    • Li, G.1    Pickup, P.G.2
  • 24
    • 33750937538 scopus 로고    scopus 로고
    • Nanostructured Pt/C and Pd/C catalysts for direct formic acid fuel cells
    • Liu Z, Hong L, Tham MP, Lim TH, Jiang H. Nanostructured Pt/C and Pd/C catalysts for direct formic acid fuel cells. J Power Sources 2006;161:831-5.
    • (2006) J Power Sources , vol.161 , pp. 831-835
    • Liu, Z.1    Hong, L.2    Tham, M.P.3    Lim, T.H.4    Jiang, H.5
  • 25
    • 0029271732 scopus 로고
    • Oxygen reduction on platinum low-index single-crystal surfaces in sulfuric acid solution: Rotating ring-Pt(hkl) disk studies
    • Markovic NM, Gasteiger HA, Ross PN. Oxygen reduction on platinum low-index single-crystal surfaces in sulfuric acid solution: rotating ring-Pt(hkl) disk studies. J Phys Chem 1995;99:3411-5.
    • (1995) J Phys Chem , vol.99 , pp. 3411-3415
    • Markovic, N.M.1    Gasteiger, H.A.2    Ross, P.N.3
  • 28
    • 0038587071 scopus 로고    scopus 로고
    • Impedance studies on direct methanol fuel cell anodes
    • Muller JT, Urban PM, Holderich WF. Impedance studies on direct methanol fuel cell anodes. J Power Sources 1999;84:157-60.
    • (1999) J Power Sources , vol.84 , pp. 157-160
    • Muller, J.T.1    Urban, P.M.2    Holderich, W.F.3
  • 29
    • 0001026315 scopus 로고
    • Ohmic potential measured by interrupter techniques
    • Newman J. Ohmic potential measured by interrupter techniques. J Electrochem Soc 1970;117:507-8.
    • (1970) J Electrochem Soc , vol.117 , pp. 507-508
    • Newman, J.1
  • 30
    • 0036476076 scopus 로고    scopus 로고
    • Examining a potential fuel cell poison: A voltammetry study of the influence of carbon dioxide on the hydrogen oxidation capability of carbon-supported Pt and PtRu anodes
    • Papageorgopoulos DC, De Bruijn FA. Examining a potential fuel cell poison: a voltammetry study of the influence of carbon dioxide on the hydrogen oxidation capability of carbon-supported Pt and PtRu anodes J. Electrochem. Soc 149 2002;A140-5.
    • (2002) J. Electrochem. Soc , vol.149
    • Papageorgopoulos, D.C.1    De Bruijn, F.A.2
  • 31
    • 0026138376 scopus 로고
    • 2 reduction reaction at the platinum/Nafion® interface using a solid-state electrochemical cell
    • 2 reduction reaction at the platinum/Nafion® interface using a solid-state electrochemical cell. J Electrochem Soc 1991;138:916-21.
    • (1991) J Electrochem Soc , vol.138 , pp. 916-921
    • Parthasarathy, A.1    Martin, C.R.2
  • 32
    • 0026913131 scopus 로고
    • Temperature dependence of the electrode kinetics of oxygen reduction at the platinum/Nafion® interface-A microelectrode investigation
    • Parthasarathy A, Srinivasan S, Appleby AJ. Temperature dependence of the electrode kinetics of oxygen reduction at the platinum/Nafion® interface-a microelectrode investigation. J Electrochem Soc 1992;139:2530-7.
    • (1992) J Electrochem Soc , vol.139 , pp. 2530-2537
    • Parthasarathy, A.1    Srinivasan, S.2    Appleby, A.J.3
  • 33
    • 0035808152 scopus 로고    scopus 로고
    • Oxygen reduction on a high-surface area Pt/Vulcan carbon catalyst: A thin-film rotating ring-disk electrode study
    • Paulus UA, Schmidt TJ, Gasteiger HA, Behm RJ. Oxygen reduction on a high-surface area Pt/Vulcan carbon catalyst: a thin-film rotating ring-disk electrode study. J Electroanal Chem 2001;495:134-45.
    • (2001) J Electroanal Chem , vol.495 , pp. 134-145
    • Paulus, U.A.1    Schmidt, T.J.2    Gasteiger, H.A.3    Behm, R.J.4
  • 35
    • 33748413167 scopus 로고    scopus 로고
    • Electrochemical impedance spectroscopy for direct methanol fuel cell diagnostics
    • Piela P, Fields R, Zelenay P. Electrochemical impedance spectroscopy for direct methanol fuel cell diagnostics. J Electrochem Soc 2006;153:A1902-13.
    • (2006) J Electrochem Soc , vol.153
    • Piela, P.1    Fields, R.2    Zelenay, P.3
  • 36
    • 0026835219 scopus 로고
    • Nafion distribution in gas diffusion electrodes for solid-polymer- electrolyte-fuel-cell applications
    • Poltarzewski Z, Staiti P, Alderucci V, Wieczorek W, Giordano N. Nafion distribution in gas diffusion electrodes for solid-polymer-electrolyte-fuel-cell applications. J Electrochem Soc 1992;139:761-5.
    • (1992) J Electrochem Soc , vol.139 , pp. 761-765
    • Poltarzewski, Z.1    Staiti, P.2    Alderucci, V.3    Wieczorek, W.4    Giordano, N.5
  • 37
    • 4544296026 scopus 로고    scopus 로고
    • Investigation of oxygen gain in polymer electrolyte membrane fuel cells
    • Prasanna M, Ha HY, Cho EA, Hong SA, Oh IH. Investigation of oxygen gain in polymer electrolyte membrane fuel cells. J Power Sources 2004;137:1-8.
    • (2004) J Power Sources , vol.137 , pp. 1-8
    • Prasanna, M.1    Ha, H.Y.2    Cho, E.A.3    Hong, S.A.4    Oh, I.H.5
  • 40
    • 0037168023 scopus 로고    scopus 로고
    • Performance of 2-propanol in direct-oxidation fuel cells
    • Qi Z, Kaufman A. Performance of 2-propanol in direct-oxidation fuel cells. J Power Sources 2002;112:121-9.
    • (2002) J Power Sources , vol.112 , pp. 121-129
    • Qi, Z.1    Kaufman, A.2
  • 41
    • 0038823811 scopus 로고    scopus 로고
    • Liquid-feed direct oxidation fuel cells using neat 2-propanol as fuel
    • Qi Z, Kaufman A. Liquid-feed direct oxidation fuel cells using neat 2-propanol as fuel. J Power Sources 2003;118:54-60.
    • (2003) J Power Sources , vol.118 , pp. 54-60
    • Qi, Z.1    Kaufman, A.2
  • 42
    • 0024607017 scopus 로고
    • Perfluorosulfonimide as an additive in phosphoric acid fuel cell
    • Razaq M, Razaq A, Yeager E. Perfluorosulfonimide as an additive in phosphoric acid fuel cell. J Electrochem Soc 1989;136:385-90.
    • (1989) J Electrochem Soc , vol.136 , pp. 385-390
    • Razaq, M.1    Razaq, A.2    Yeager, E.3
  • 44
    • 0031238067 scopus 로고    scopus 로고
    • Electro-osmotic drag of water in ionomeric membranes: New measurements employing a direct methanol fuel cell
    • Ren X, Henderson W, Gottesfeld S. Electro-osmotic drag of water in ionomeric membranes: new measurements employing a direct methanol fuel cell. J Electrochem Soc 1997;144:L267-70.
    • (1997) J Electrochem Soc , vol.144
    • Ren, X.1    Henderson, W.2    Gottesfeld, S.3
  • 45
    • 0000038994 scopus 로고    scopus 로고
    • Nuclear magnetic resonance and voltammetry studies of carbon monoxide adsorption and oxidation on a carbon-supported platinum fuel cell electrocatalyst
    • Rush BM, Reimer JA, Cairns EJ. Nuclear magnetic resonance and voltammetry studies of carbon monoxide adsorption and oxidation on a carbon-supported platinum fuel cell electrocatalyst. J Electrochem Soc 2001;148:A137-48.
    • (2001) J Electrochem Soc , vol.148
    • Rush, B.M.1    Reimer, J.A.2    Cairns, E.J.3
  • 46
    • 0023455724 scopus 로고
    • The kinetics of oxygen reduction in molten phosphoric acid at high temperatures
    • Scharifker BR, Zelenay P, Bockris JOM. The kinetics of oxygen reduction in molten phosphoric acid at high temperatures. J Electrochem Soc 1977;134:2714-25.
    • (1977) J Electrochem Soc , vol.134 , pp. 2714-2725
    • Scharifker, B.R.1    Zelenay, P.2    Bockris, J.O.M.3
  • 47
    • 0032668165 scopus 로고    scopus 로고
    • Rotating disk electrode measurements on the CO tolerance of a high-surface area Pt/Vulcan carbon fuel cell catalyst
    • Schmidt TJ, Gasteiger HA, Behma RJ. Rotating disk electrode measurements on the CO tolerance of a high-surface area Pt/Vulcan carbon fuel cell catalyst. J Electrochem Soc 1999;146:1296-304.
    • (1999) J Electrochem Soc , vol.146 , pp. 1296-1304
    • Schmidt, T.J.1    Gasteiger, H.A.2    Behma, R.J.3
  • 48
    • 0032122852 scopus 로고    scopus 로고
    • Characterization of high-surface-area electrocatalysts using a rotating disk electrode configuration
    • Schmidt TJ, Gasteiger HA, Stab GD, Urban PM, Kolb DM, Behm RJ. Characterization of high-surface-area electrocatalysts using a rotating disk electrode configuration. J Electrochem Soc 1998;145:2354-58.
    • (1998) J Electrochem Soc , vol.145 , pp. 2354-2358
    • Schmidt, T.J.1    Gasteiger, H.A.2    Stab, G.D.3    Urban, P.M.4    Kolb, D.M.5    Behm, R.J.6
  • 49
    • 31044433934 scopus 로고    scopus 로고
    • Pt-Ru-Ir nanoparticles prepared by vapor deposition as a very efficient anode catalyst for methanol fuel cells
    • Sivakumar P, Tricoli V. Pt-Ru-Ir nanoparticles prepared by vapor deposition as a very efficient anode catalyst for methanol fuel cells. Electrochem Solid-State Lett 2006;9:A167-70.
    • (2006) Electrochem Solid-State Lett , vol.9
    • Sivakumar, P.1    Tricoli, V.2
  • 50
    • 0030129788 scopus 로고    scopus 로고
    • Proton conductivity of Nafion 117 as measured by a four-electrode AC impedance method
    • Sone Y, Ekdunge P, Simonsson D. Proton conductivity of Nafion 117 as measured by a four-electrode AC impedance method. J Electrochem Soc 1996;143:1254-9.
    • (1996) J Electrochem Soc , vol.143 , pp. 1254-1259
    • Sone, Y.1    Ekdunge, P.2    Simonsson, D.3
  • 51
    • 0030084123 scopus 로고    scopus 로고
    • Characterization of polymer electrolyte fuel cells using AC impedance spectroscopy
    • Springer TE, Zawodzinski TA, Wilson MS, Gottesfeld S. Characterization of polymer electrolyte fuel cells using AC impedance spectroscopy. J Electrochem Soc 1996;143:587-99.
    • (1996) J Electrochem Soc , vol.143 , pp. 587-599
    • Springer, T.E.1    Zawodzinski, T.A.2    Wilson, M.S.3    Gottesfeld, S.4
  • 53
    • 33748100890 scopus 로고    scopus 로고
    • PEM fuel cell cathode carbon corrosion due to the formation of air/fuel boundary at the anode
    • Tang H, Qi Z, Ramani M, Elter JF. PEM fuel cell cathode carbon corrosion due to the formation of air/fuel boundary at the anode. J Power Sources 2006;158:1306-12.
    • (2006) J Power Sources , vol.158 , pp. 1306-1312
    • Tang, H.1    Qi, Z.2    Ramani, M.3    Elter, J.F.4
  • 55
    • 0141884964 scopus 로고    scopus 로고
    • Change of electrochemical impedance spectra during CO poisoning of the Pt and Pt-Ru anodes in a membrane fuel cell (PEFC)
    • Wagner N, Schulze M. Change of electrochemical impedance spectra during CO poisoning of the Pt and Pt-Ru anodes in a membrane fuel cell (PEFC). Electrochim Acta 2003;48:3899-907.
    • (2003) Electrochim Acta , vol.48 , pp. 3899-3907
    • Wagner, N.1    Schulze, M.2
  • 57
    • 33644804381 scopus 로고    scopus 로고
    • Steady-state and EIS investigations of hydrogen electrodes and membranes in polymer electrolyte fuel cells: I. modeling
    • Wiezell K, Gode P, Lindbergh G. Steady-state and EIS investigations of hydrogen electrodes and membranes in polymer electrolyte fuel cells: I. modeling. J Electrochem Soc 2006;153:A749-58.
    • (2006) J Electrochem Soc , vol.153
    • Wiezell, K.1    Gode, P.2    Lindbergh, G.3
  • 58
    • 33644790292 scopus 로고    scopus 로고
    • Steady-state and EIS investigations of hydrogen electrodes and membranes in polymer electrolyte fuel cells: II. Experimental
    • Wiezell K, Gode P, Lindbergh G. Steady-state and EIS investigations of hydrogen electrodes and membranes in polymer electrolyte fuel cells: II. Experimental. J Electrochem Soc 2006;153:A759-64.
    • (2006) J Electrochem Soc , vol.153
    • Wiezell, K.1    Gode, P.2    Lindbergh, G.3
  • 59
    • 0010428222 scopus 로고
    • Hydrogen adsorption on platinum, iridium and rhodium electrodes at reduced temperatures and the determination of real surface area
    • Woods R. Hydrogen adsorption on platinum, iridium and rhodium electrodes at reduced temperatures and the determination of real surface area. J Electroanal Chem 1974;49217-26.
    • (1974) J Electroanal Chem , pp. 49217-49226
    • Woods, R.1
  • 60
    • 20344367747 scopus 로고    scopus 로고
    • Microstructural changes of membrane electrode assemblies during PEFC durability testing at high humidity conditions
    • Xie J, Wood III DL, More KL, Atanassov P, Borup RL. Microstructural changes of membrane electrode assemblies during PEFC durability testing at high humidity conditions. J Electrochem Soc 2005;152:A1011-20.
    • (2005) J Electrochem Soc , vol.152
    • Xie, J.1    Wood III, D.L.2    More, K.L.3    Atanassov, P.4    Borup, R.L.5
  • 61
    • 33748430198 scopus 로고    scopus 로고
    • Discrepancies in the measurement of ionic conductivity of PEMs using two-and four-probe AC impedance spectroscopy
    • Xie Z, Song C, Andreaus B, Navessin T, Shi Z, Zhang J, et al. Discrepancies in the measurement of ionic conductivity of PEMs using two-and four-probe AC impedance spectroscopy. J Electrochem Soc 2006;153:E173-8.
    • (2006) J Electrochem Soc , vol.153
    • Xie, Z.1    Song, C.2    Andreaus, B.3    Navessin, T.4    Shi, Z.5    Zhang, J.6
  • 62
    • 33845361119 scopus 로고    scopus 로고
    • Investigation of platinum oxidation in PEM fuel cells at various relative humidities
    • Xu H, Kunz R, Fenton JM. Investigation of platinum oxidation in PEM fuel cells at various relative humidities. Electrochem Solid-State Lett 2007;10:B1-5.
    • (2007) Electrochem Solid-State Lett , vol.10
    • Xu, H.1    Kunz, R.2    Fenton, J.M.3
  • 66
    • 33947601750 scopus 로고    scopus 로고
    • PEM fuel cell open circuit voltage (OCV) in the temperature range of 23 °c to 120 °c
    • Zhang J, Tang Y, Song C, Zhang J, Wang H. PEM fuel cell open circuit voltage (OCV) in the temperature range of 23 °C to 120 °C. J Power Sources 2006;163:532-7.
    • (2006) J Power Sources , vol.163 , pp. 532-537
    • Zhang, J.1    Tang, Y.2    Song, C.3    Zhang, J.4    Wang, H.5


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.