메뉴 건너뛰기




Volumn 31, Issue 3-4, 2006, Pages 165-179

Spectroscopic studies of synthetic and natural beidellites: A review

Author keywords

Beidellite; Hydrothermal synthesis; Infrared spectroscopy; Raman spectroscopy; Solid state Nuclear Magnetic Resonance spectroscopy; X ray photoelectron spectroscopy

Indexed keywords

HYDROTHERMAL SYNTHESIS; INFRARED SPECTROSCOPY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; RAMAN SPECTROSCOPY; STRUCTURE (COMPOSITION); X RAY PHOTOELECTRON SPECTROSCOPY;

EID: 33144457844     PISSN: 01691317     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.clay.2005.10.003     Document Type: Article
Times cited : (27)

References (88)
  • 3
    • 0007095626 scopus 로고
    • The hexa-aquo aluminum cation as reference in aluminum-27 NMR spectroscopy. Possible detection of second sphere effects
    • J.W. Akitt J.M. Elders The hexa-aquo aluminum cation as reference in aluminum-27 NMR spectroscopy. Possible detection of second sphere effects Journal of Magnetic Resonance 63 1985 587-589
    • (1985) Journal of Magnetic Resonance , vol.63 , pp. 587-589
    • Akitt, J.W.1    Elders, J.M.2
  • 5
    • 33845184982 scopus 로고
    • 113Cd nuclear magnetic resonance study of exchanged montmorillonite
    • 113Cd nuclear magnetic resonance study of exchanged montmorillonite Journal of Physical Chemistry 93 1989 4847-4855
    • (1989) Journal of Physical Chemistry , vol.93 , pp. 4847-4855
    • Bank, S.B.J.F.1    Ellis, P.D.2
  • 8
    • 0027789056 scopus 로고
    • Reflectance and Mössbauer spectroscopy of ferrihydrite-montmorillonite assemblages as Mars soil analogues
    • J.L. Bishop C.M. Pieters R.G. Burns Reflectance and Mössbauer spectroscopy of ferrihydrite-montmorillonite assemblages as Mars soil analogues Geochimica et Cosmochimica Acta 57 1993 4583-4595
    • (1993) Geochimica Et Cosmochimica Acta , vol.57 , pp. 4583-4595
    • Bishop, J.L.1    Pieters, C.M.2    Burns, R.G.3
  • 9
    • 0028552957 scopus 로고
    • Infrared spectroscopic analyses on the nature of water in montmorillonite
    • J.L. Bishop C.M. Pieters J.O. Edwards Infrared spectroscopic analyses on the nature of water in montmorillonite Clays and Clay Minerals 42 6 1994 702-716
    • (1994) Clays and Clay Minerals , vol.42 , Issue.6 , pp. 702-716
    • Bishop, J.L.1    Pieters, C.M.2    Edwards, J.O.3
  • 10
    • 0031268331 scopus 로고    scopus 로고
    • Acid-activated organoclays: Preparation, characterization and catalytic activity of acid-treated tetraalkylammonium-exchanged smectites
    • C. Breen R. Watson J. Madejova P. Komadel Z. Klapyta Acid-activated organoclays: Preparation, characterization and catalytic activity of acid-treated tetraalkylammonium-exchanged smectites Langmuir 13 24 1997 6473-6479
    • (1997) Langmuir , vol.13 , Issue.24 , pp. 6473-6479
    • Breen, C.1    Watson, R.2    Madejova, J.3    Komadel, P.4    Klapyta, Z.5
  • 12
    • 0001336851 scopus 로고
    • Pillared clays
    • R. Burch Pillared clays Catalysis Today 2 2-3 1988 185-368
    • (1988) Catalysis Today , vol.2 , Issue.2-3 , pp. 185-368
    • Burch, R.1
  • 14
    • 0019654003 scopus 로고
    • Water molecules and hydroxyl groups in montmorillonites as studied by near infrared spectroscopy
    • F. Cariati L. Erre G. Micera P. Piu C. Gessa Water molecules and hydroxyl groups in montmorillonites as studied by near infrared spectroscopy Clays and Clay Minerals 29 2 1981 157-159
    • (1981) Clays and Clay Minerals , vol.29 , Issue.2 , pp. 157-159
    • Cariati, F.1    Erre, L.2    Micera, G.3    Piu, P.4    Gessa, C.5
  • 15
    • 0021052507 scopus 로고
    • Effect of layer charge on the near-infrared spectra of water molecules in smectites and vermiculites
    • F. Cariati L. Erre G. Micera P. Piu C. Gessa Effect of layer charge on the near-infrared spectra of water molecules in smectites and vermiculites Clays and Clay Minerals 31 6 1983 447-449
    • (1983) Clays and Clay Minerals , vol.31 , Issue.6 , pp. 447-449
    • Cariati, F.1    Erre, L.2    Micera, G.3    Piu, P.4    Gessa, C.5
  • 16
    • 0021022059 scopus 로고
    • Polarization of water molecules in phyllosilicates in relation to exchange cations as studied by near infrared spectroscopy
    • F. Cariati L. Erre G. Micera P. Piu C. Gessa Polarization of water molecules in phyllosilicates in relation to exchange cations as studied by near infrared spectroscopy Clays and Clay Minerals 31 2 1983 155-157
    • (1983) Clays and Clay Minerals , vol.31 , Issue.2 , pp. 155-157
    • Cariati, F.1    Erre, L.2    Micera, G.3    Piu, P.4    Gessa, C.5
  • 17
    • 0019675472 scopus 로고
    • Determination of tetrahedral substitutions and interlayer surface heterogeneity from vibrational spectra of ammonium in smectites
    • B. Chourabi J.J. Fripiat Determination of tetrahedral substitutions and interlayer surface heterogeneity from vibrational spectra of ammonium in smectites. Clays and Clay Minerals 29 1981 260-268
    • (1981) Clays and Clay Minerals , vol.29 , pp. 260-268
    • Chourabi, B.1    Fripiat, J.J.2
  • 20
    • 0016984948 scopus 로고
    • Formation of phyllosilicates from pure silica-alumina gels
    • C.R. De Kimpe Formation of phyllosilicates from pure silica-alumina gels Clays and Clay Minerals 24 1976 200-207
    • (1976) Clays and Clay Minerals , vol.24 , pp. 200-207
    • De Kimpe, C.R.1
  • 22
    • 0035702227 scopus 로고    scopus 로고
    • Porous clays and pillared clay-based catalysts: Part 2. A review of the catalytic and molecular sieve applications
    • Z. Ding J.T. Kloprogge R.L. Frost G.Q. Lu H.Y. Zhu Porous clays and pillared clay-based catalysts: Part 2. A review of the catalytic and molecular sieve applications Journal of Porous Materials 8 2001 273-293
    • (2001) Journal of Porous Materials , vol.8 , pp. 273-293
    • Ding, Z.1    Kloprogge, J.T.2    Frost, R.L.3    Lu, G.Q.4    Zhu, H.Y.5
  • 25
    • 33144487787 scopus 로고    scopus 로고
    • Drift spectroscopy for determination of organic acids on montmorillonite
    • (Progress in Fourier Transform Spectroscopy)
    • R.L. Frost R.W. Parker Drift spectroscopy for determination of organic acids on montmorillonite Mikrochimica Acta. Supplementum 14 1997 691-692
    • (1997) Mikrochimica Acta. Supplementum , vol.14 , pp. 691-692
    • Frost, R.L.1    Parker, R.W.2
  • 29
    • 0343222515 scopus 로고
    • Clay mineral synthesis: II. A randomly interstratified aluminian montmorillonoid
    • W.T. Granquist S.S. Pollack Clay mineral synthesis: II. A randomly interstratified aluminian montmorillonoid American Mineralogist 52 1967 212-226
    • (1967) American Mineralogist , vol.52 , pp. 212-226
    • Granquist, W.T.1    Pollack, S.S.2
  • 30
    • 0342787907 scopus 로고
    • Clay mineral synthesis: III. Rapid hydrothermal crystalization of an aluminian smectite
    • W.T. Granquist G.W. Hoffmann R.C. Boteler Clay mineral synthesis: III. Rapid hydrothermal crystalization of an aluminian smectite Clays and Clay Minerals 20 1972 323-329
    • (1972) Clays and Clay Minerals , vol.20 , pp. 323-329
    • Granquist, W.T.1    Hoffmann, G.W.2    Boteler, R.C.3
  • 31
    • 0001324741 scopus 로고
    • Preparation of silicate composition by a gelling method
    • D.L. Hamilton C.M. Henderson Preparation of silicate composition by a gelling method Mineralogical Magazine 36 1968 832-838
    • (1968) Mineralogical Magazine , vol.36 , pp. 832-838
    • Hamilton, D.L.1    Henderson, C.M.2
  • 32
    • 0001411940 scopus 로고
    • Visible and near-infrared spectra of minerals and rocks: I. Silicate minerals
    • G.R. Hunt J.W. Salisbury Visible and near-infrared spectra of minerals and rocks: I. Silicate minerals Modern Geology 1 1970 283-300
    • (1970) Modern Geology , vol.1 , pp. 283-300
    • Hunt, G.R.1    Salisbury, J.W.2
  • 33
    • 0342787898 scopus 로고
    • Hydrothermal Method for Manufacturing a Novel Catalytic Material, Catalysts Containing Said Material and Processes Using Said Catalysts U.S
    • J. Jaffe Hydrothermal Method for Manufacturing a Novel Catalytic Material, Catalysts Containing Said Material and Processes Using Said Catalysts, U.S 1974
    • (1974)
    • Jaffe, J.1
  • 36
    • 0038944664 scopus 로고
    • Effect of hydration o the local symmetry around aluminum in ZSM-5 zeolites studied by aluminum-27 nuclear magnetic resonance
    • A.P.M. Kentgens K.F.M.G.J. Scholle W.S. Veeman Effect of hydration o the local symmetry around aluminum in ZSM-5 zeolites studied by aluminum-27 nuclear magnetic resonance Journal of Physical Chemistry 87 1983 4357-4360
    • (1983) Journal of Physical Chemistry , vol.87 , pp. 4357-4360
    • Kentgens, A.P.M.1    Scholle, K.F.M.G.J.2    Veeman, W.S.3
  • 37
    • 0031655474 scopus 로고    scopus 로고
    • Synthesis of smectites and porous pillared clay catalysts: Review
    • J.T. Kloprogge Synthesis of smectites and porous pillared clay catalysts: Review Journal of Porous Media 5 1 1998 5-42
    • (1998) Journal of Porous Media , vol.5 , Issue.1 , pp. 5-42
    • Kloprogge, J.T.1
  • 38
    • 0033393286 scopus 로고    scopus 로고
    • Infrared emission spectroscopy of Al-pillared beidellite
    • J.T. Kloprogge R.L. Frost Infrared emission spectroscopy of Al-pillared beidellite Applied Clay Science 15 1999 431-445
    • (1999) Applied Clay Science , vol.15 , pp. 431-445
    • Kloprogge, J.T.1    Frost, R.L.2
  • 39
    • 0012742705 scopus 로고
    • Hydrothermal synthesis of ammonium-beidellite
    • J.T. Kloprogge R. Vogels Hydrothermal synthesis of ammonium-beidellite Clays and Clay Minerals 43 1 1995 135-137
    • (1995) Clays and Clay Minerals , vol.43 , Issue.1 , pp. 135-137
    • Kloprogge, J.T.1    Vogels, R.2
  • 46
    • 0026852037 scopus 로고
    • Temperature influence on the Al13 comple x in partially neutralized aluminum solutions: An aluminum-27 nuclear magnetic resonance study
    • J.T. Kloprogge D. Seykens J.W. Geus J.B.H. Jansen Temperature influence on the Al13 comple x in partially neutralized aluminum solutions: An aluminum-27 nuclear magnetic resonance study Journal of Non-Crystalline Solids 142 1-2 1992 87-93
    • (1992) Journal of Non-Crystalline Solids , vol.142 , Issue.1-2 , pp. 87-93
    • Kloprogge, J.T.1    Seykens, D.2    Geus, J.W.3    Jansen, J.B.H.4
  • 48
    • 0028167346 scopus 로고
    • The effect of thermal treatment on the properties of hydroxy-Al and hydroxy-Ga pillared montmorillonite and beidellite
    • J.T. Kloprogge E. Booy J.B.H. Jansen J.W. Geus The effect of thermal treatment on the properties of hydroxy-Al and hydroxy-Ga pillared montmorillonite and beidellite Clay Minerals 29 1994 153-167
    • (1994) Clay Minerals , vol.29 , pp. 153-167
    • Kloprogge, J.T.1    Booy, E.2    Jansen, J.B.H.3    Geus, J.W.4
  • 49
    • 0000727514 scopus 로고    scopus 로고
    • An infrared emission spectroscopic study of the thermal transformation mechanisms in Al13-pillared clay catalsts with and without tetrahedral substitutions
    • J.T. Kloprogge R. Fry R.L. Frost An infrared emission spectroscopic study of the thermal transformation mechanisms in Al13-pillared clay catalsts with and without tetrahedral substitutions Journal of Catalysis 184 1999 157-171
    • (1999) Journal of Catalysis , vol.184 , pp. 157-171
    • Kloprogge, J.T.1    Fry, R.2    Frost, R.L.3
  • 51
    • 0033560550 scopus 로고    scopus 로고
    • Infrared emission spectroscopic study of the dehydroxylation via surface silanol groups of synthetic and natural beidellite
    • J.T. Kloprogge S. Komarneni K. Yanagisawa R. Fry R.L. Frost Infrared emission spectroscopic study of the dehydroxylation via surface silanol groups of synthetic and natural beidellite Journal of Colloid and Interface Science 212 1999 562-569
    • (1999) Journal of Colloid and Interface Science , vol.212 , pp. 562-569
    • Kloprogge, J.T.1    Komarneni, S.2    Yanagisawa, K.3    Fry, R.4    Frost, R.L.5
  • 52
    • 0033684343 scopus 로고    scopus 로고
    • The effect of increasing layer charge on the infrared absorption spectra of synthetic beidellites
    • J.T. Kloprogge L. Hickey R.L. Frost The effect of increasing layer charge on the infrared absorption spectra of synthetic beidellites Journal of Materials Science Letters 19 13 2000 1131-1134
    • (2000) Journal of Materials Science Letters , vol.19 , Issue.13 , pp. 1131-1134
    • Kloprogge, J.T.1    Hickey, L.2    Frost, R.L.3
  • 54
    • 0002188052 scopus 로고    scopus 로고
    • Structure and chemical characteristics of modified clays
    • Series E (atural Microporous Materials in Environmental)
    • P. Komadel Structure and chemical characteristics of modified clays NATO Science Series. Series E 362 1999 3-18
    • (1999) NATO Science Series , vol.362 , pp. 3-18
    • Komadel, P.1
  • 55
    • 0021366618 scopus 로고
    • The effect of pressure on the dehydration reaction of interlayer water in
    • A.F. Koster van Groos S. Guggenheim The effect of pressure on the dehydration reaction of interlayer water in American Mineralogist 69 1984 872-879
    • (1984) American Mineralogist , vol.69 , pp. 872-879
    • Koster van Groos, A.F.1    Guggenheim, S.2
  • 56
    • 0021366618 scopus 로고
    • The effect of pressure on the dehydration reaction of interlayer water in Na-montmorillonite (SWy-1)
    • A.F. Koster van Groos S. Guggenheim The effect of pressure on the dehydration reaction of interlayer water in Na-montmorillonite (SWy-1) American Mineralogist 69 1984 872-879
    • (1984) American Mineralogist , vol.69 , pp. 872-879
    • Koster van Groos, A.F.1    Guggenheim, S.2
  • 57
    • 0022926280 scopus 로고
    • Dehydration of K-exchanged montmorillonite at elevated temperatures and
    • A.F. Koster van Groos S. Guggenheim Dehydration of K-exchanged montmorillonite at elevated temperatures and Clays and Clay Minerals 34 1986 281-286
    • (1986) Clays and Clay Minerals , vol.34 , pp. 281-286
    • Koster van Groos, A.F.1    Guggenheim, S.2
  • 58
    • 0022926280 scopus 로고
    • Dehydration of K-exchanged montmorillonite at elevated temperatures and pressures
    • A.F. Koster van Groos S. Guggenheim Dehydration of K-exchanged montmorillonite at elevated temperatures and pressures Clays and Clay Minerals 34 1986 281-286
    • (1986) Clays and Clay Minerals , vol.34 , pp. 281-286
    • Koster van Groos, A.F.1    Guggenheim, S.2
  • 59
    • 0023497152 scopus 로고
    • Dehydration of a Ca-and a Mg-exchanged montmorillonite (SWy-1) at elevated pressures
    • A.F. Koster van Groos S. Guggenheim Dehydration of a Ca-and a Mg-exchanged montmorillonite (SWy-1) at elevated pressures American Mineralogist 72 1987 292-298
    • (1987) American Mineralogist , vol.72 , pp. 292-298
    • Koster van Groos, A.F.1    Guggenheim, S.2
  • 60
    • 0023497152 scopus 로고
    • Dehydration of a Ca-and a Mg-exchanged montmorillonite (SWy-1) at elevated pressures
    • A.F. Koster van Groos S. Guggenheim Dehydration of a Ca- and a Mg-exchanged montmorillonite (SWy-1) at elevated pressures American Mineralogist 72 1987 292-298
    • (1987) American Mineralogist , vol.72 , pp. 292-298
    • Koster van Groos, A.F.1    Guggenheim, S.2
  • 63
    • 0000120780 scopus 로고
    • Gel preparation of starting materials for hydrothermal experimentation
    • W.C. Luth C.O. Ingamells Gel preparation of starting materials for hydrothermal experimentation American Mineralogist 50 1965 255-258
    • (1965) American Mineralogist , vol.50 , pp. 255-258
    • Luth, W.C.1    Ingamells, C.O.2
  • 64
    • 0034535033 scopus 로고    scopus 로고
    • Effects of chemical composition and temperature of heating on the infrared spectra of Li-saturated dioctahedral smectites. (I) Mid-infrared region
    • J. Madejova J. Bujdak S. Petit P. Komadel Effects of chemical composition and temperature of heating on the infrared spectra of Li-saturated dioctahedral smectites. (I) Mid-infrared region Clay Minerals 35 5 2000 739-751
    • (2000) Clay Minerals , vol.35 , Issue.5 , pp. 739-751
    • Madejova, J.1    Bujdak, J.2    Petit, S.3    Komadel, P.4
  • 65
    • 0034535035 scopus 로고    scopus 로고
    • Effects of chemical composition and temperature of heating on the infrared spectra of Li-saturated dioctahedral smectites. (II) Near-infrared region
    • J. Madejova J. Bujdak S. Petit P. Komadel Effects of chemical composition and temperature of heating on the infrared spectra of Li-saturated dioctahedral smectites. (II) Near-infrared region Clay Minerals 35 5 2000 753-761
    • (2000) Clay Minerals , vol.35 , Issue.5 , pp. 753-761
    • Madejova, J.1    Bujdak, J.2    Petit, S.3    Komadel, P.4
  • 67
    • 0023524865 scopus 로고
    • Pillaring processes of smectites with and without tetrahedral substitutions
    • D.G.L. Plee J.J. Fripiat Pillaring processes of smectites with and without tetrahedral substitutions Clays and Clay Minerals 35 1987 81-88
    • (1987) Clays and Clay Minerals , vol.35 , pp. 81-88
    • Plee, D.G.L.1    Fripiat, J.J.2
  • 68
    • 0342352154 scopus 로고
    • Zeolite-Like Materials from Clays, France
    • D. Plee et. al. Zeolite-Like Materials from Clays, France 1984
    • (1984)
    • Plee, D.1
  • 69
    • 33750639833 scopus 로고
    • High-resolution solid-state 27Al and 29Si nuclear magnetic resonance study of pillared clays
    • D. Plee F. Borg L. Gatineau J.J. Fripiat High-resolution solid-state 27Al and 29Si nuclear magnetic resonance study of pillared clays Journal of the American Chemical Society 107 1985 2362-2369
    • (1985) Journal of the American Chemical Society , vol.107 , pp. 2362-2369
    • Plee, D.1    Borg, F.2    Gatineau, L.3    Fripiat, J.J.4
  • 70
    • 0347120224 scopus 로고
    • Small-angle X-ray scattering from hydrolyzed aluminum nitrate solutions
    • W.V. Rausch H.D. Bale Small-angle X-ray scattering from hydrolyzed aluminum nitrate solutions Journal of Chemical Physics 40 1964 3391-3394
    • (1964) Journal of Chemical Physics , vol.40 , pp. 3391-3394
    • Rausch, W.V.1    Bale, H.D.2
  • 71
    • 0003717030 scopus 로고
    • Minerals of the montmorillonite group
    • U.S. Geological Survey Professional Paper
    • C.S. Ross S.B. Hendricks Minerals of the montmorillonite group U.S. Geological Survey Professional Paper 205-B 1945
    • (1945) , vol.205 B
    • Ross, C.S.1    Hendricks, S.B.2
  • 73
    • 0343221602 scopus 로고
    • A note on some properties of synthetic montmorillonites
    • R. Roy L.B. Sand A note on some properties of synthetic montmorillonites American Mineralogist 41 1956 505-509
    • (1956) American Mineralogist , vol.41 , pp. 505-509
    • Roy, R.1    Sand, L.B.2
  • 75
    • 0010569506 scopus 로고
    • Acidity and catalytic properties of pillared montmorillonite and beidellite
    • Denver
    • A. Schutz et. al. Acidity and catalytic properties of pillared montmorillonite and beidellite Proceedings of the International Clay Conf. Denver 1985 305-310
    • (1985) Proceedings of the International Clay Conf. , pp. 305-310
    • Schutz, A.1
  • 76
    • 0023524869 scopus 로고
    • Preparation and characterisation of bidimensional zeolitic structures obtained from synthetic beidellite and hydroxy-aluminum solutiions
    • A. Schutz W.E.E. Stone G. Poncelet J.J. Fripiat Preparation and characterisation of bidimensional zeolitic structures obtained from synthetic beidellite and hydroxy-aluminum solutiions Clays and Clay Minerals 35 1987 251-261
    • (1987) Clays and Clay Minerals , vol.35 , pp. 251-261
    • Schutz, A.1    Stone, W.E.E.2    Poncelet, G.3    Fripiat, J.J.4
  • 77
    • 0021080511 scopus 로고
    • Infrared spectroscopic study of adsorbed water on reduced-charge Na/ Li-montmorillonites
    • G. Sposito R. Prost J.-P. Gaultier Infrared spectroscopic study of adsorbed water on reduced-charge Na/Li-montmorillonites Clays and Clay Minerals 31 1 1983 9-16
    • (1983) Clays and Clay Minerals , vol.31 , Issue.1 , pp. 9-16
    • Sposito, G.1    Prost, R.2    Gaultier, J.-P.3
  • 78
    • 0021335069 scopus 로고
    • The distribution of octahedral cations in the 2:1 layers of dioctahedral smectites studied by oblique-texture electron diffraction
    • S.I. Tispursky V.A. Drits The distribution of octahedral cations in the 2:1 layers of dioctahedral smectites studied by oblique-texture electron diffraction Clay Minerals 19 1984 177-193
    • (1984) Clay Minerals , vol.19 , pp. 177-193
    • Tispursky, S.I.1    Drits, V.A.2
  • 79
    • 0000514354 scopus 로고
    • Two pressure vessels for silicate-water studies
    • O.F. Tuttle Two pressure vessels for silicate-water studies Geological Society of America Bulletin 60 1949 1727-1729
    • (1949) Geological Society of America Bulletin , vol.60 , pp. 1727-1729
    • Tuttle, O.F.1
  • 80
    • 0002357938 scopus 로고    scopus 로고
    • Preparation and catalytic properties of cationic and anionic clays
    • A. Vaccari Preparation and catalytic properties of cationic and anionic clays Catalysis Today 41 1998 53-71
    • (1998) Catalysis Today , vol.41 , pp. 53-71
    • Vaccari, A.1
  • 83
    • 0023960478 scopus 로고
    • Pillared clays - A historical perspective
    • D.E.W. Vaughan Pillared clays - A historical perspective Catalysis Today 2 1988 187-198
    • (1988) Catalysis Today , vol.2 , pp. 187-198
    • Vaughan, D.E.W.1
  • 88
    • 0030146536 scopus 로고    scopus 로고
    • Hydrothermal synthesis of Na-beidellite from coprecipitated gel
    • K. Yanagisawa et. al. Hydrothermal synthesis of Na-beidellite from coprecipitated gel Journal of Materials Science Letters 15 1996 861-863
    • (1996) Journal of Materials Science Letters , vol.15 , pp. 861-863
    • Yanagisawa, K.1


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.