J. Jpn. Soc. Soil Phys.
౔৕ͷ෺ཧੑ

No. 124, p.43 ∼ 49 (2013)ਫ෼‫ٵ‬୤ணଌఆ૷ஔ “AquaLab VSA”Λ༻͍ͨ௿ਫ෼ྖҬͷ౔ͷਫ෼อ࣋‫ۂ‬ઢͷଌఆ౉ล৾ੜ 1 · ௕ా༑ཬ‫ ܙ‬1 · ࡔҪɹউ 1 · औग़৳෉ 1

Successive measurement of water retention curves for relativity dry soils using “AquaLab VSA”
Kunio WATANABE 1 , Yurie OSADA1 , Masaru SAKAI1 and Nobuo TORIDE1

Abstract: The AquaLab Vapor Sorption Analyzer (VSA)
is an automatic isotherm generator to measure water potential for a sample with a chilled-mirror dew-point sensor
while gravimetrically tracking the sample weight during
wetting and drying processes. In this study, we applied theVSA to measure water retention curves for relatively drysoils ranging from −7.2 × 104 cm to −3.2 × 106 cm, andinvestigated the accuracy of measurement and properties ofthe VSA setting parameters. We conﬁrmed that soil water
potential was equilibrated with air humidity for the DVS
method with 0.01 % h−1 of the weight trigger. The equilibrated water content by weight was almost identical regardless of the soil bulk density since the surface retention
was dominant in the dry range. The newly developed DDI(Dynamic Dewpoint Isotherm) method was validated with
the DVS method. The DDI method could accurately measure successive retention curves for 50 h measuring timewith the ﬂow rate of 100 mL min−1 . Hysteretic retention
curves as well as scanning curves in a dry range could bealso observed in a repeatable manner for Fujinomori silty
loam soil, Tokachi Andisol, and Tottori dune sand using
the DDI method.
Key Words : water retention curve, soil water potential,
chilled-mirror dew-point potentiometer, DDI method, hysteresis

1. ͸͡Ίʹ
ۙ೥ɼDecagon ࣾͷ WP4 ʹ୅ද͞ΕΔ‫ڸ‬໘ྫྷ٫࿐఺ࣜਫϙςϯγϟϧ‫ܭ‬ʢChilled-mirror dew-point potentiome-terʣ͕ී‫͠ٴ‬ɼਫ಄୯ҐͰ −5000 cm ఔ౓ҎԼͷ௿ਫਫ෼ྖҬͷਫ෼อ࣋‫ۂ‬ઢͷଌఆ๏ͱͯ͠ɼՃѹ൘๏΍ৠ‫ؾ‬ѹ๏ͱஔ͖‫׵‬ΘΓͭͭ͋ΔʢKirkham, 2005; Watanabe

et al., 2012ʣɽ౔ͷਫ෼อ࣋‫ۂ‬ઢ͸ɼࢼྉͷ࣪५΍‫ס‬૩ͷཤྺʹґଘ͢ΔɽͦͷͨΊɼ୤ਫͷओ‫ۂ‬ઢͰ͸๞࿨ࢼྉ͔Β୤ਫɼ‫ٵ‬ਫͷओ‫ۂ‬ઢͰ͸‫ס‬૩ࢼྉ͔Β‫ٵ‬ਫʹΑΓࢼྉΛ࡞੒͢
Δඞཁ͕͋Δɽ͔͠͠ɼ௿ਫ෼ྖҬͷࢼྉͰ͸ɼ࡞੒࣌ͷࢼྉ؅ཧ΍ඍগͳਫ෼ྔมԽͷௐ੔ɼਫ෼ฏߧͷ൑ఆͳͲɼཤྺΛ໌֬ʹͨ͠ࢼྉௐ੔͕೉͍͠ɽ·ͨɼ௿ਫ෼ྖҬͷਫ෼อ࣋‫ۂ‬ઢͷώεςϦγεͷଌఆྫ͕΄ͱΜͲͳ͍ͨΊɼࢼྉͷཤྺͷਫ෼อ࣋‫ۂ‬ઢʹ‫͢΅ٴ‬Ө‫ڹ‬ͷৄࡉ͸ෆ໌Ͱ͋Δɽͱ͜ΖͰɼ৯඼ͷ඼࣭؅ཧ΍คཻମͷਫৠ‫ؾ‬ಁա཰ͷଌఆ౳ʹ͸ɼࢼྉपғͷ૬ର࣪౓Λࣗಈతʹௐ੔͠ɼಉ࣌ʹࢼྉͷਫϙςϯγϟϧΛ‫ڸ‬໘ྫྷ٫࿐఺ࣜਫϙςϯγϟϧ‫Ͱܭ‬ଌఆ͢Δࣗಈਫ෼‫ٵ‬୤ணଌఆ૷ஔ͕༻͍ΒΕ͍ͯΔʢͨͱ͑͹ Barbosa-Cánovas et al., 2007; Oliver andMeinders, 2011; Barba et al., 2013ʣɽਫϙςϯγϟϧͷଌఆํࣜʹ͸ɼҰఆ࣪౓ͷۭ‫ؾ‬Λ༩͑ͯਫৠ‫ٵ͕ؾ‬ண͢ΔաఔͷࢼྉͷॏྔΛ࿈ଓଌఆ͢Δ DVSʢDynamic VaporSorptionʣํࣜͱΘ͔ͣͳ࣪౓มԽΛ༩͑ͳ͕ΒฏߧͱΈͳ͢ਫϙςϯγϟϧͱࢼྉͷॏྔΛ࿈ଓଌఆ͢Δ DDIʢDynamic Dewpoint Isothermʣํ͕ࣜ͋ΔɽDVS ͸ैདྷ͔ΒͷଌఆํࣜͰ͋ΓɼDDI ͸ Decagon ࣾͷ AquaLabVSAʢVapor Sorption Analyzer, ҎԼ VSAʣ͕৽ͨʹ࠾༻ͨ͠ํࣜͰ͋ΔɽDDI ͸ɼDVS ʹൺ΂ଌఆ͕࣌ؒ୹͘ɼߴղ૾౓ͷਫ෼อ࣋‫ۂ‬ઢ͕ಘΒΕΔಛ௃Λ࣋ͭɽ৯෼ྖҬͷ౔ͷਫϙςϯγϟϧଌఆʹ‫͞༻׆‬Ε͍ͯΔɽ͜඼ʹ͍ͭͯ͸ɼVSA Λ༻͍ͨ DVS ଌఆͱଞͷଌఆ๏ͱͷਫϙςϯγϟϧ‫Ͱܭ‬ଌఆ͞ΕΔ౔தͷਫϙςϯγϟϧͷൺֱʢShands and Labuza, 2009ʣ΍ DDI ͱ DVS ͷൺ͸ɼ௨ৗͷ༹࣭ೱ౓ͷൣғͰ͸ϚτϦοΫϙςϯγϟϧֱ‫ݕ‬౼ʢSchmidt and Lee, 2009ʣ΋ਐΊΒΕ͍ͯΔɽ͠ʹ౳͍͠ʢJury and Horton, 2004ʣɽͦ͜Ͱɼଌఆͷਝ଎͔͠ɼVSA ͷ౔ࢼྉ΁ͷԠ༻ྫ͸গͳ͘ɼDDI ଌఆʹΑ͞΍؆ศ͔͞Βɼ‫ڸ‬໘ྫྷ٫࿐఺ࣜਫϙςϯγϟϧ‫ܭ‬͸ɼ௿Δ౔ͷਫ෼อ࣋‫ۂ‬ઢʹରͯ͠͸ɼ౔ࢼྉͱૹ෩ۭ‫ؾ‬ͷฏߧʹ͍ͭͯͷ‫ݕ‬౼͕ඞཁͰ͋Δɽ

1 Graduate

School of Bioresources, Mie University, 1577 KurimaMachiya, Tsu 514-8507, Japan. Corresponding authorɿ౉ล৾ੜɼࡾ
ॏେֶɹେֶӃੜ෺ࢿ‫ڀݚֶݯ‬Պ
2013 ೥ 4 ݄ 2 ೔डߘɹ 2013 ೥ 6 ݄ 27 ೔डཧͦ͜Ͱຊ‫Ͱڀݚ‬͸ɼ·ͣ VSA ͷଌఆ‫ݪ‬ཧΛ঺հ্ͨ͠Ͱɼ௿ਫ෼ྖҬͷ౔ͷਫ෼อ࣋‫ۂ‬ઢଌఆ΁ͷ DVS ͱDDI ͷద༻Λ‫ݕ‬౼͢ΔɽͦΕͧΕͷํࣜͷઃఆύϥϝʔ౔৕ͷ෺ཧੑɹୈ 124 ߸ɹ (2013)44ଌఆ͢Δɽࢼྉͷਫ෼ྔʹ͍ͭͯ͸ɼॳ‫ظ‬ʢ͋Δ͍͸࠷ऴʣࢼྉͷ‫ؚ‬ਫൺΛ‫ج‬४஋ͱͯ͠ɼࢼྉॏྔͷ૬ରతมԽ͔Β‫ؚ‬ਫൺΛ‫ٻ‬ΊΔɽࢼྉͷਫϙςϯγϟϧਫ಄ hT ʢcmʣ͸ɼ·ͣࢼྉԹ౓ T ʢKʣʹରԠ͢Δ๞࿨ਫৠ‫ؾ‬ѹ P∗ ʢPaʣͱ‫ڸ‬໘Թ౓ʹରԠ͢Δ๞࿨ਫৠ‫ؾ‬ѹ PʢPaʣΛͦΕͧΕࢉग़͠ɼ૬ର࣪౓ aw = P/P∗ Λ‫ٻ‬ΊΔɽ͜ͷ aw ͸ਫ෼‫׆‬ੑͱ΋Α͹ΕΔʢStokes and Robinson, 1949; Campbell

et al., 2010ʣɽͦͯ͠ɼ࣍ͷ Kelvin ํఔࣜʹ‫ ͖ͮج‬hT Λࢉग़͢ΔʢSchoﬁeld, 1935; Kirkham, 2005ʣɽ
hT =Fig. 1 VSA ࢼྉࣨͷ֓೦ਤɽ
Schematics of the VSA sample chamber.

100 RTln aw
ρw g M(1)͜͜ͰɼR ͸‫ؾ‬ମఆ਺ɼρw ͸ਫͷີ౓ɼg ͸ॏྗՃ଎౓ɼ
M ͸ਫͷ෼ࢠྔͰ͋ΔɽhT ͸ɼϚτϦοΫϙςϯγϟϧ h ͱਁಁϙςϯγϟϧͷ࿨Ͱ͋Δɽͳ͓ɼຊใͰ͸ɼϙςϯγϟϧʹ͸ਫ಄୯ҐʢcmʣΛ༻͍Δɽʢ1ʣࣜʹै͑͹ɼ25 ◦ C ʹ͓͍ͯ aw ͕ 0.600, 0.950,

Fig. 2 ‫ٵ‬Ҿ๏ɼՃѹ൘๏ɼWP4 Ͱଌఆͨ͠ 3 छͷ౔ͷਫ෼อ࣋‫ۂ‬ઢɽ

Water retention curves for three types of soils measured withhanging water, pressure plate and chilled-mirror dew-point methods.

0.995 ͱ૿Ճ͢ΔͱɼhT ͸ −7.03 × 105 , −7.06 × 104 ,−6.90 × 103 cm ͱࢦ਺ؔ਺తʹ૿Ճ͢Δɽ·ͨɼʢ1ʣࣜ
ͷ aw ͱ hT ͷਫ਼౓͸ɼओʹ੺֎Թ౓‫ʹܭ‬ΑΔ T ͷଌఆਫ਼౓ʹґଘ͢Δɽ·ͨɼaw ͕๞࿨ʹ͍ۙྖҬ΄ͲɼT ͷଌఆਫ਼౓ͷӨ‫ڹ‬Λड͚Δɽͨͱ͑͹ɼT ͷਫ਼౓͕
±0.012 ◦ C Ͱ͋Ε͹ɼhT ͷਫ਼౓͸ ±1000 cmɼ±0.12 ◦ CͰ͋Ε͹ ±104 cm ͱͳΔɽۙ೥ɼWP4 ͸੺֎Թ౓‫ܭ‬ͷਫ਼౓Λ ±0.01 ◦ C ʹ޲্ͤ͞ɼ૬ର࣪౓ͷଌఆՄೳྖҬΛ 0.1 < aw < 0.993ʢ − 3.2 × 106 < hT < −1000 cmʣʹ޿͛ͨɽҰํɼ‫ࡏݱ‬ͷ VSA ͷ੺֎Թ౓‫ܭ‬ͷਫ਼౓͸ ±0.1
◦ C Ͱ͋Δɽ VSA ͷଌఆՄೳྖҬ͸ɼૹ෩ۭ‫ؾ‬ͷ࣪౓ௐ੔ͷ‫ػ‬ցత໰୊ʹ΋ؔ࿈ͯ͠ɼ࢓্༷ 0.03 < aw <0.95ʢ − 5 × 106 < hT < −7.2 × 104 cmʣʹ੍‫͞ݶ‬Ε͍ͯΔɽ

λɼଌఆ্ͷ஫ҙ఺Λ໌Β͔ʹ͠ɼDDI ʹΑΔฏߧϙς

2.2 ૬ର࣪౓ͷ੍‫ޚ‬
VSA Ͱ͸ɼ‫ס‬૩ۭ‫࣪ͱؾ‬५ۭ‫ؾ‬ͷࠞ߹ʹΑΓࢼྉࣨϯγϟϧଌఆͷਫ਼౓Λ‫ݕ‬౼͢Δɽͦͯ͠ɼҟͳΔ౔ੑͷʹૹ෩͢Δۭ‫ؾ‬ͷ࣪౓Λௐ੔͢Δɽ͜ͷ‫ؾۭڅڙ‬ͷ࣪౓௿ਫ෼ྖҬͷ౔ͷਫ෼อ࣋‫ۂ‬ઢɼ‫ٵ‬ਫ‫ۂ‬ઢͱ୤ਫ‫ۂ‬ઢͷͷ੍‫ʹޚ‬͸ɼDVS ͱ DDI ͷ 2 ํ͔ࣜΒબ୒Ͱ͖ΔɽैώεςϦγεͷଌఆ݁ՌΛใࠂ͢Δɽ

2. VSA ͷଌఆ‫ݪ‬ཧ
2.1 ਫϙςϯγϟϧͱਫ෼ྔͷଌఆདྷํࣜͰ͋Δ DVS ͸ɼҰఆ࣪౓ͷۭ‫ؾ‬Λૹ෩͠ɼࢼྉ
ॏྔ m ͱ૬ର࣪౓ aw Λଌఆͨ͠‫ޙ‬ɼૹ෩ۭ‫ؾ‬ͷ࣪౓Λஈ֊తʹมߋͤͯ͞ଌఆΛ‫܁‬Γฦ͢ɽଌఆʹؔ͢Δઃఆ߲໨͸ɼଌఆ։͓࢝Αͼऴྃʢ͋Δ͍͸ંΓฦ͠఺ʣͷ͍ͯΔɽ0.5 ∼ 5 g ͷࢼྉΛ಺‫ ܘ‬37 mm ͷεςϯϨεηaw ɼࢼྉࣨͷԹ౓ T ɼstep ͱΑ͹ΕΔૹ෩ۭ‫ؾ‬ͷ࣪౓ͷࠁΈ෯ Δastep ɼtrigger ͱΑ͹ΕΔฏߧ൑ఆʹؔ͢Δ‫ج‬४஋ mtrig ɼevent ͱΑ͹ΕΔ mtrig ͷ൑ఆ‫܁‬Γฦ͠ճ਺ ntrig ɼ֤ஈ֊ͷ࠷େ‫ܭ‬ଌ࣌ؒͷ Δtmax Ͱ͋ΔɽDVS Ͱ͸ɼૹ෩ྲྀྔͷௐઅ͸Ͱ͖ͳ͍ɽmtrig ͷ‫ج‬४ͷৄࡉ͸࢓༷ॻʹ͸ϧ಺ʹ޿͛ɼਫ਼ີട্ʹ੩ஔ͢ΔɽࢼྉࣨΛີด‫ޙ‬ɼઃ໌‫͞ه‬Ε͍ͯͳ͍͕ɼଌఆॏྔͷ૬ରมԽ཰ʹ‫جͮ͘ج‬Fig. 1 ʹɼVSA ͷࢼྉࣨͷ֓ཁΛࣔ͢ɽࢼྉࣨͷ༰ੵ
͸ 15 mL ఔ౓Ͱ͋Δɽࢼྉ্ࣨ෦ʹ͸ϖϧνΣૉࢠͱαʔϛελΛඋ͑ͨ‫ڸ‬ɼ੺֎Թ౓‫ܭ‬ɼখ‫ܕ‬ϑΝϯ͕ɼࢼྉࣨԼ෦ʹ͸ਫ਼౓ 0.1 mg ͷਫ਼ີട͕ͦΕͧΕ഑ஔ͞ΕఆԹ౓ʹอͪͳ͕Βখ‫ܕ‬ϑΝϯΛճ͠ɼࢼྉࣨͷۭ‫ؾ‬ͷ४஋Ͱ͋Γ୯Ґ͸ % h−1 Ͱ͋Δɽଌఆॏྔͷ૬ରมԽ૬ର࣪౓ͱࢼྉΛฏߧͤ͞Δɽ࣍ʹɼϨʔβʔޫΛ‫ڸ‬໘཰͕࿈ଓͯ͠ ntrig ճ mtrig ҎԼʹͳͬͨ࣌఺Ͱ m Λଌఆʹরࣹ͠ͳ͕Βɼ‫ڸ‬ͷද໘Թ౓ΛϖϧνΣૉࢠʹΑΓม͠ɼૹ෩ۭ‫ؾ‬ͷ࣪౓Λ Δastep มԽͤ͞Δɽmtrig ͕খ͘͞Խͤ͞Δɽͦͯ͠ɼ൓ࣹޫͷ‫౓ڧ‬มԽ͔Β‫ڸ‬໘ͷ݁࿐Λ

ntrig ͷճ਺͕ଟ͍΄Ͳ aw ʹฏߧͨ͠ m ͷਪఆਫ਼౓͸ߴ൑ఆ͠ɼ݁࿐࣌ͷ‫ڸ‬໘Թ౓ΛαʔϛελͰଌఆ͢Δɽ·͘ͳΔ͕ɼଌఆ࣌ؒ͸௕͘ͳΔɽ·ͨɼmtrig ͷ৚݅ΛຬͨɼࢼྉͷԹ౓ͱॏྔΛ੺֎Թ౓‫ͱܭ‬ਫ਼ີടͰͦΕͧΕͨ͞ͳͯ͘΋ɼ‫ܭ‬ଌ͕࣌ؒ Δtmax ʹୡ͢Δͱɼ࣍ͷઃఆ‫ڀݚ‬ϊʔτɿਫ෼‫ٵ‬୤ணଌఆ૷ஔʠAquaLab VSAʡΛ༻͍ͨ௿ਫ෼ྖҬͷ౔ͷਫ෼อ࣋‫ۂ‬ઢͷଌఆ

45

Fig. 3 DVS ͱ DDI Ͱଌఆͨ͠ʢaʣ૬ର࣪౓ aw ͱʢbʣࢼྉͷॏྔมԽ Δmɽ
DVS vs. DDI for (a) relative humidity aw and (b) sample weight Δm as a function of relative time.

࣪౓ͷଌఆʹҠߦ͢ΔɽͦͷͨΊɼେ͖ͳ mtrig ɼ·ͨখௗऔٰ࠭࠭ʢρb = 1.45 g cm−3 ʣͷ୤ਫաఔͷਫ෼อ࣋͞ͳ ntrig ͱ Δtmax ͸ɼଌఆ࣌ؒΛ୹ॖ͢Δ͕ m ͷฏߧͷ‫ۂ‬ઢͰ͋Δɽਤதͷ࣮ઢ͸ɼvan Genuchtenʢ1980ʣͷࣜ৴པੑΛ௿Լͤ͞ΔɽʹΑΔద߹‫ۂ‬ઢͰ͋Δɽ

ҰํɼVSA ʹ৽ͨʹ࠾༻͞Εͨ DDI ͸ɼ‫ؾۭڅڙ‬ͷ࣪౓Λ࿈ଓతʹมԽͤ͞ͳ͕ΒɼฏߧͱΈͳ͢ m ͱ aw

VSA ͷଌఆʹ͸ɼे෼ʹ‫ס‬૩ͨ͠ॳ‫ظ‬ঢ়ଶͱͯ͠ɼ෩‫ ʹޙס‬2 mm ᝲ௨աͷ౻ͷ৿౔ͱࠇϘΫ౔ɼਫચ‫ʹޙ‬࿍Λಉ࣌ʹଌఆ͢Δɽଌఆʹؔ͢Δઃఆ߲໨͸ɼଌఆ։࢝

‫ס‬૩ͨ͠ௗऔٰ࠭࠭Λ༻͍ͨɽ͜ͷͱ͖ɼࢼྉΛਫ෼อ͓Αͼऴྃͷ aw ɼࢼྉࣨͷ T ɼresolution ͱΑ͹ΕΔ aw࣋‫ۂ‬ઢͷ ρb ͰηϧʢFig. 1ʣʹॆర͢Δͱɼଌఆ։࢝ͷͷग़ྗղ૾౓ Δares ɼ୯Ґ࣌ؒ͋ͨΓͷૹ෩ྲྀྔ Qair ɼશaw ͱࢼྉ͕ฏߧ͢Δ·Ͱͷ͕࣌ؒ௕͘ͳΓɼͦͷؒͷaw ͷ͹Β͖͕ͭେ͖͘ͳͬͨɽ౻ͷ৿౔ͷ৔߹ɼࢼྉΛΏΔ͘ηϧఈʹ޿͛ΔΑ͏ʹ ρb = 0.84 g cm−3 Ͱॆరͨ͠ͱ͖͸ɼρb = 1.18 g cm−3 ͷ৔߹ʹൺ΂ͯଌఆ։࢝ͷaw ʹୡ͢Δ·Ͱʹཁ͢Δ͕࣌ؒ 23 h ୹͘ɼ͜ͷؒͷ awͷ͹Β͖ͭ΋൒෼ఔ౓ͱͳͬͨɽҰํɼଌఆ։࢝ͷ aw౸ୡ‫ʹޙ‬ಘΒΕΔ hT ʹ͸ɼρb ͷӨ‫ڹ‬͸ೝΊΒΕͳ͔ͬଌఆͷ࠷େ‫ܭ‬ଌ࣌ؒͷ tmax Ͱ͋ΔɽDDI ʹ͓͚Δ Δaresͷৄࡉ͸࢓༷ॻʹࣔ͞Ε͍ͯͳ͍͕ɼΔares ͕খ͍͞΄ͲɼΑΓখ͞ͳࠁΈ෯Ͱ aw ͕มԽ͢Δɽ Δares Λ 0.01
͔Β 0.1 ·Ͱେ͖ͯ͘͠΋ɼଌఆ࣌ؒ͸ 3 ׂఔ౓͔͠୹ॖ͞Εͳ͍ͷͰɼҎԼɼຊ‫Ͱڀݚ‬͸ൺֱత࿈ଓతʹଌఆ݁ՌΛग़ྗͰ͖Δਪ঑஋ͷ Δares = 0.01 Λ༻͍ͨɽฏߧաఔͷਫ෼มԽͷ‫ݕ‬౼΍ɼ͋Δಛఆͷਫϙςϯͨɽ͜Ε͸ɼ௿ਫ෼ྖҬͰ͸౔ཻࢠද໘ͷอਫ͕୎ӽ͢γϟϧͷਫ෼ྔΛಘΔʹ͸ DVS ͕ద͓ͯ͠Γɼ࿈ଓ͠ΔͨΊͰ͋Δɽͦ͜Ͱɼ͍ͣΕͷࢼྉ΋ 2 g ఔ౓ΛΏΔͨਫ෼อ࣋‫ۂ‬ઢͷଌఆʹ͸ DDI ͕ద͍ͯ͠Δɽ͘ηϧఈʹ෴͏Α͏ʹ޿͛ͯଌఆʹ‫ͨ͠ڙ‬ɽॏྔมԽ͔

3. VSA ͷ౔΁ͷద༻ྫ
3.1 ࢼྉ

Β‫·ٻ‬Δ‫ؚ‬ਫൺ w ͸ɼͦΕͧΕͷࢼྉͷ ρb Λ৐ͯ͡ମੵ‫ؚ‬ਫ཰ θ ʹ‫ͨ͠ࢉ׵‬ɽ

3.2 DVS ͱ DDI ͷઃఆύϥϝʔλ·ͨɼ͍ͣΕͷ౔ʹ͍ͭͯ΋ి‫఻ؾ‬ಋ౓͸‫ۃ‬Ίͯ௿͘
DVS ʹ͍ͭͯ͸౻ͷ৿౔ɼDDI ʹ͍ͭͯ͸౻ͷ৿౔ɼ−1 ɼh ʹର͢ΔਁಁϙςϯγϟϧʢECT
1:5 < 8.5 mS m ʣेউࠇϘΫ౔ɼௗऔٰ࠭࠭ͷ 3 छͷ౔Λର৅ʹ VSA ͷద༻ΛࢼΈͨɽ౻ͷ৿౔͸ɼ༗‫ػ‬෺Λ΄ͱΜͲ‫͍ͳ·ؚ‬੒෼ͷ‫د‬༩͸े෼ʹখ͍͞ͱߟ͑ΒΕͨɽͦ͜ͰɼҎԼԼ૚౔Ͱ͋Γɼ೪౔෼͕ 24 % Λ઎ΊΔγϧτϩʔϜͰͷٞ࿦Ͱ͸ɼVSA Ͱଌఆ͞ΕΔ hT ΛϚτϦοΫϙςϯ͋ΔɽेউࠇϘΫ౔͸ɼ๺ւಓ೶‫ڀݚۀ‬ηϯλʔժࣨ‫ݚ‬‫఺ڌڀ‬ͷແ২ੜะ৔ͷද૚͔Β࠾౔ͨ͠ɽ Fig. 2 ͸ɼ‫ٵ‬Ҿ๏ɼՃѹ൘๏ɼWP4 Ͱଌఆͨ͠౻ͷ৿౔ʢ‫ס‬૩ີ౓ρb = 1.18 g cm−3 ʣɼेউࠇϘΫ౔ʢρb = 0.95 g cm−3 ʣɼγϟϧਫ಄ h ͱΈͳ͠ɼਫ෼อ࣋‫ۂ‬ઢʢθ –h ؔ܎ʣΛ‫ٻ‬Ίͨɽͳ͓ɼ͢΂ͯͷଌఆ͸ 25 ◦ C ͷ߃ԹࣨͰɼࢼྉࣨ

ͷઃఆԹ౓Λ 25 ◦ C ͱͯ͠ߦͬͨɽFig. 3 ʹɼDVS ͱ DDI ʹΑΔ౻ͷ৿౔ͷ‫ٵ‬ਫ‫ޙ‬୤ਫա

46౔৕ͷ෺ཧੑɹୈ 124 ߸ɹ (2013)aw = 0.95 ͸ h = −7.2 × 104 cm ʹରԠ͢Δɽࢼྉͷଌఆ‫ج‬४ͷҰ൪‫͍͠ݫ‬৚݅ͱͯ͠༩͑ͨ mtrig = 0.01 % h−1 ɼΔtmax ͷ੍‫͠ͳݶ‬ͷଌఆ஋Λ࣮ઢͰ݁ΜͰࣔ͠ɼҎԼͷൺֱͰ͸࠷΋৴པੑͷߴ͍σʔλͱΈͳͨ͠ɽ‫ٵ‬ਫաఔʹൺ΂ͯ୤ਫաఔͷਫ෼อ࣋‫ۂ‬ઢ͸େ͖ͳਫ෼ྔ θ Λࣔ͠ɼώεςϦγε͕‫ݟ‬ΒΕͨɽh = −2.5 × 105 cm ෇ۙͰ‫ٵ‬ਫաఔͱ୤ਫաఔͷ θ ͷࠩ͸࠷େʹͳΓɼΔθ =0.008

m3 m−3 ఔ౓Ͱ͋ͬͨɽ·ͨɼ͜ͷ‫ٵ‬୤ਫաఔશྖҬͷଌఆʹ͸ 84.2 h Λཁͨ͠ɽ

mtrig Λ 0.1% h−1 ʹେ͖͘͢Δͱɼଌఆ࣌ؒ͸ 42.2 hͱ൒‫͕ͨ͠ݮ‬ɼ‫ٵ‬ਫ‫ۂ‬ઢΛશମతʹ Δθ =0.002 m3 m−3ఔ౓աখධՁͨ͠ɽ‫ʹٯ‬ɼmtrig Λ 0.01 % h−1 ΑΓখ͞
͘͢Δͱɼଌఆ࣌ؒ͸‫ʹܹٸ‬௕͘ͳ͕ͬͨɼଌఆ͞ΕΔਫ෼อ࣋‫ۂ‬ઢ͸΄΅౳͔ͬͨ͠ɽ
ҟͳΔฏߧ൑ఆ‫ج‬४஋ mtrig ͱ࠷େ‫ܭ‬ଌ࣌ؒ Δtmax Λ༻͍ͯ DVS Ͱ‫ٻ‬Ίͨ౻ͷ৿౔ͷਫ෼อ࣋‫ۂ‬ઢɽ

Fig. 4

Water retention curves for Fujinomori silt loam measured with
DVS with different trigger mtrig and timeout Δtmax .

Ұํɼmtrig = 0.01 % h−1 ͷଌఆ࣌ؒ͸ɼΔtmax = 1 hͰ͸ 10.8 hɼΔtmax = 0.25 h Ͱ͸ 5.2 h ͱ୹͘ͳ͕ͬͨɼh ͕େ͖͍΄Ͳ‫ٵ‬ਫաఔͷ θ ΛաখධՁͨ͠ɽΔtmax Λઃఆ͢ΔͱɼંΓฦ͠ͷ୤ਫ։࢝࣌ʢaw = 0.95ʣͷ θ ͕খ͍ͨ͞ΊɼΔtmax ͷ੍‫ʹ͠ͳݶ‬ൺ΂ͯ୤ਫաఔॳ‫ظ‬ͷθ ΛաখධՁͨ͠ɽ͔͠͠ɼh < −106 cm Ͱ͸‫ ʹٯ‬θ ΛաେධՁͨ͠ɽ͜Ε͸ɼΔtmax ͕খ͗͢͞Δͱɼ࣪౓ͷ௿Լʹରͯ͠ɼࢼྉ͕े෼ʹ୤ਫͤͣʹ࣍ͷ૬ର࣪౓΁Ҡߦ͢ΔͨΊͰ͋Δɽ2 g ఔ౓ͷ౻ͷ৿౔Ͱ͸ɼΔtmax ͷ੍‫͠ͳݶ‬ͷ৔߹ɼ֤ஈ֊ͷଌఆʹ͸໿ 10 h Λཁͨ͠ɽ௨ৗ
ͷࢼྉͷ৔߹ɼDVS ʹ͓͚Δ m ͷߴ͍ਫ਼౓ͷଌఆʹ͸ɼ

Δmtrig = 0.01 % h−1 ఔ౓Ͱ Δtmax > 10 h ͷઃఆ͕ඞཁͰ
͋Δɽ·ͨɼ୹࣌ؒͷଌఆͷͨΊʹখ͞ͳ Δtmax ͷઃఆ͕ඞཁͳ৔߹͸ɼFig. 4 ʹࣔͨ͠ํ๏ʹΑΔଌఆਫ਼౓ͷ֬ೝ͕ඞཁͰ͋Δɽ

Fig. 5 ͸ɼҟͳΔૹ෩ྲྀྔ Qair ͷ DDI ଌఆʹΑΔ౻ͷ৿౔ͷਫ෼อ࣋‫ۂ‬ઢͰ͋Δɽ‫ٵ‬୤ਫͷ৚݅͸ɼFig. 3ɼ੍‫ͨ͠ͱ͠ͳݶ‬ɽ·ͨɼଌఆ࣌ؒ͸ํࣜʹΑΓҟͳΔͨ

Fig. 4 ͱ౳͍͠ɽे෼ʹฏߧͨ͠ਫ෼อ࣋‫ۂ‬ઢͱͯ͠ɼ
Fig. 4 ʹࣔͨ͠ mtrig = 0.01 % h−1 ɼΔtmax ͷ੍‫͠ͳݶ‬ͷ
DVS ͷ݁ՌΛϓϩοτͨ͠ɽDDI ଌఆ͸ɼQair = 500mL min−1 Ͱ͸‫ٵ‬ਫաఔͷ θ Λ΍΍աখධՁͨ͠ɽ͍ͣ
Εͷ Qair ʹ͓͍ͯ΋ɼ୤ਫաఔͰ͸΍΍աେධՁͷ܏޲͕‫ݟ‬ΒΕ͕ͨɼશମతʹ͸ DVS ͷਫ෼อ࣋‫ۂ‬ઢͱΑ͘Ұகͨ͠ɽDDI ͷଌఆ࣌ؒ͸ɼQair = 500 mL min−1 Ͱ͸ 49 hɼQair = 100 mL min−1 Ͱ͸ 54 h Ͱ͋ΓɼQair =25 mL min−1 Ͱ͸ 408 h ͱେ͖͘૿Ճͨ͠ɽ·ͨɼਤʹ͸͍ࣔͯ͠ͳ͍͕ɼ͞Βʹখ͞ͳ Qair = 10 mL min−1 Ͱ͸ɼh = −1.6 × 105 cm Ҏ্ʹ‫ٵ‬ਫͰ͖ͳ͔ͬͨɽଞͷΊɼԣ࣠ͷ࣌ؒ͸ɼશଌఆ࣌ؒΛ 1 ͱͨ͠૬ର࣌ؒͰࣔ౔ੑͷଌఆ݁Ռ΋ߟྀ͢Δͱɼ௨ৗͷ౔ੑͷࢼྉʹ͓͚

Fig. 5 ҟͳΔૹ෩ྲྀྔ Qair Λ༻͍ͯ DDI Ͱ‫ٻ‬Ίͨ౻ͷ৿౔ͷਫ෼อ࣋‫ۂ‬ઢɽ
Water retention curves for Fujinomori silt loam measured with
DDI with different ﬂow rate Qair .

ఔͷ૬ର࣪౓ aw ͱࢼྉͷॏྔมԽ Δm ͷଌఆྫΛࣔ͢ɽॳ‫ظ‬͸ aw = 0.1ɼંΓฦ͠఺͸ aw = 0.95 Ͱ͋ΔɽDVSͷઃఆ৚݅͸ɼΔastep = 0.1ɼmtrig = 0.01 % h−1 ɼntrig =3 ճɼDDI ͸ɼQair = 100 mL min−1 ɼΔtmax ɼtmax ͸࣌ؒͨ͠ɽDVS Ͱ͸ aw ͱ m ͕֊ஈঢ়ʹมԽ͢Δͷʹର͠ɼΔਫ਼౓ͷߴ͍ DDI ଌఆʹ͸ɼQair = 100 mL min−1 ఔ౓DDI ͷ aw ͱ m ͸࿈ଓతʹมԽ͢ΔɽDVS ͷ֤ஈ֊ʹ͓͍ͯɼaw ͱ m ͷมԽ͕े෼ʹখ͘͞ͳͬͨͱ͖ɼۭ͕࣮༻తͱ‫͑ݴ‬Δɽ‫ؾ‬ͷ࣪౓ͱࢼྉͷਫ෼ྔ͕ฏߧʹୡͨ͠ͱΈͳ͢͜ͱ͕Ͱ͖Δɽͦ͜ͰɼDDI ଌఆͷଥ౰ੑΛɼे෼ʹฏߧͯ͠

3.3 ౔ͷਫ෼อ࣋‫ۂ‬ઢͱώεςϦγε౻ͷ৿౔ʹରͯ͠͸ɼQair = 100 mL min−1 ͷ DDI ʹΑΓҟͳΔંΓฦ͠఺ͷਫ෼อ࣋‫ۂ‬ઢ΋ଌఆͨ͠ɽFig.
6ʢaʣ͸ɼaw = 0.1 ͔Βͷ‫ٵ‬ਫ‫ޙ‬ɼҟͳΔંΓฦ͠఺
Fig. 4 ͸ɼmtrig ͱ Δtmax ͷҟͳΔ DVS ଌఆʹΑΔ౻ ʢaw = 0.95ɼ0.9ɼ0.8ɼ0.6ʣ͔Β aw = 0.1 ΁ͷ୤ਫաఔɼ
Fig. 6ʢbʣ͸ aw = 0.95 ͔Βͷ୤ਫ‫ޙ‬ɼҟͳΔંΓฦ͠ͷ৿౔ͷ‫ٵ‬ਫ‫ޙ‬୤ਫաఔͷਫ෼อ࣋‫ۂ‬ઢͰ͋Δɽ‫ٵ‬୤ਫ
6
৚݅͸ Fig. 3 ͱ౳͘͠ɼaw = 0.1 ͸ h = −3.2 × 10 cmɼ ఺ʢaw = 0.8ɼ0.6ɼ0.3ɼ0.1ʣ͔Β aw = 0.95 ΁ͷ‫ٵ‬ਫ͍Δ DVS ଌఆͱͷൺֱ͔Β‫ݕ‬౼ͨ͠ɽ‫ڀݚ‬ϊʔτɿਫ෼‫ٵ‬୤ணଌఆ૷ஔʠAquaLab VSAʡΛ༻͍ͨ௿ਫ෼ྖҬͷ౔ͷਫ෼อ࣋‫ۂ‬ઢͷଌఆ

47

Fig. 6 DDI Ͱ‫ٻ‬Ίͨʢaʣ‫ٵ‬ਫ‫ޙ‬୤ਫաఔͱʢbʣ୤ਫ‫ٵޙ‬ਫաఔͷ౻ͷ৿౔ͷ૸ࠪ‫ۂ‬ઢɽ
Scanning curves for Fujinomori silt loam measured with DDI for (a) wetting and subsequent drying,and (b) drying and subsequent wetting.

աఔͰ͋Δɽaw Λ 0.1 ͔Β 0.95 ʹ্ঢ‫ ʹޙ‬0.1 ΁࠶Լ߱ͨ͠‫ٵ‬ਫ‫ޙ‬୤ਫաఔͱɼaw Λ 0.95 ͔Β 0.1 ʹԼ߱‫ޙ‬
ʹ 0.95 ΁࠶্ঢͨ͠୤ਫ‫ٵޙ‬ਫաఔͷਫ෼อ࣋‫ۂ‬ઢ͸Ұக͓ͯ͠ΓɼώεςϦγεଌఆͷ࠶‫ݱ‬ੑ͸ߴ͍ɽ·ͨɼ

aw = 0.1 ͸௨ৗͷ෩‫ס‬৚݅ΑΓ‫ס‬૩ঢ়ଶʹ͋ΔɽͦͷͨΊɼaw = 0.1 ͔Βͷ‫ٵ‬ਫ‫ۂ‬ઢ͸ɼ‫ٵ‬ਫͷओ‫ۂ‬ઢͱΈͳͤΔɽҰํɼओ୤ਫ‫ۂ‬ઢ͸๞࿨͔Βͷ୤ਫ‫ۂ‬ઢͰ͋ΔͷͰɼaw = 0.95 ͔Βͷ୤ਫ‫ۂ‬ઢ͸ɼ୤ਫ૸ࠪ‫ۂ‬ઢͰ͋Δɽ
Fig. 6ʢaʣͷ‫ٵ‬ਫ‫ޙ‬୤ਫաఔͷਫ෼อ࣋‫ۂ‬ઢ͸ɼओ‫ٵ‬ਫ‫ۂ‬ઢΛંΓฦ͠఺·ͰͨͲͬͨ‫ޙ‬ɼaw = 0.95 ͔Βͷ୤ਫ‫ۂ‬ઢʹ઴ۙ͢Δ୤ਫ૸ࠪ‫ۂ‬ઢΛࣔͨ͠ɽͦͯ͠ɼ࠷ऴతʹ࢝఺ͷ aw = 0.1 ͷ h = −3.2 × 106 cm Ͱดͨ͡ɽFig. 6ʢbʣͷ୤ਫ‫ٵޙ‬ਫաఔʹ͓͍ͯ΋ɼaw = 0.95 ͔Βͷ୤ਫ૸ࠪ‫ۂ‬ઢΛͨͲͬͨ‫ޙ‬ɼંΓฦ͠఺͔Β aw =0.1 ͔Βͷओ‫ٵ‬ਫ‫ۂ‬ઢʹ઴ۙ͢ΔΑ͏ͳ‫ٵ‬ਫ૸ࠪ‫ۂ‬ઢΛࣔ͠ɼ࢝఺ͷ aw = 0.95 ͷ h = −7.2 × 104 cm Ͱดͨ͡ɽҎ্ͷΑ͏ʹɼDDI ͸ɼ༷ʑͳ‫ٵ‬୤ਫաఔͷ૸ࠪ‫ۂ‬ઢΛߴ͍࠶‫ݱ‬ੑͰଌఆՄೳͰ͋Δɽ

Fig. 7 ʹɼFig. 6 ͱಉ͡ DDI Λ༻͍ͯɼaw = 0.1 ͔Β aw = 0.95 ΁ͷ‫ٵ‬ਫ‫ޙ‬ɼ୤ਫͤͯ͞ଌఆͨ͠౻ͷ৿౔ɼेউࠇϘΫ౔ɼௗऔٰ࠭࠭ͷਫ෼อ࣋‫ۂ‬ઢΛࣔ͢ɽਤʹ͸ɼFig. 2 ʹࣔͨ͠ WP4 ʹΑΔଌఆ݁Ռ΋ซ‫ͨ͠ه‬ɽௗऔٰ࠭࠭ʹ͍ͭͯ͸ɼଞͷ౔ʹൺ΂ͯ θ ͕খ͍ͨ͞Ίɼ

Fig. 7ʢbʣʹॎ࣠Λ֦େͨ͠ਤΛࣔͨ͠ɽ͍ͣΕͷࢼྉ΋ɼ‫ٵ‬ਫ‫ޙ‬୤ਫաఔͷਫ෼อ࣋‫ۂ‬ઢΛ 50 h ఔ౓ͰଌఆͰ͖ͨɽ
ώεςϦγε͸ɼ౻ͷ৿౔ͱൺ΂ͯ͸খ͍͕͞ɼेউࠇϘΫ౔ɼௗऔٰ࠭࠭ʹ͓͍ͯ΋‫͞࡯؍‬Εͨɽͦͷ࠷େͷࠩ͸ɼेউࠇϘΫ౔Ͱ͸ Δθ = 0.005 m3 m−3 ɼௗऔٰ࠭࠭Ͱ͸ Δθ = 0.0005 m3 m−3 Ͱ͋ͬͨɽ͜͏ͨ͠௿ਫ෼ྖҬͷώεςϦγε͸ɼ౔ཻࢠද໘ʹ͓͚Δਫͷ઀৮֯ͷώεςϦγεɼද໘ૈ౓΍ૄਫੑͷޮՌʢIsraelachvili,2011ʣ͕‫ݪ‬Ҽͱߟ͑ΒΕΔɽͦͷͨΊɼ͕࠭େ൒Λ઎Ίͯൺද໘ੵ͕খ͍͞ௗऔٰ࠭࠭Ͱ͸ɼώεςϦγε͸খ

DDI ͱ WP4 Ͱ‫ٻ‬Ίͨʢaʣ3 छྨͷ౔ͷਫͷਫ෼อ࣋‫ۂ‬ઢͱʢbʣௗऔٰ࠭࠭ͷਫ෼อ࣋‫ۂ‬ઢͷ֦େਤɽʷ͸ VSAɼ˚ɼ˔ɼ˜͸ WP4 ͷଌఆ஋ɽFig. 7(a) Water retention curves for three different soils measured withDDI(ʷ) and a chilled-mirror dew-point method (˚, ˔, ˜).
(b) Enlargement for the Tottori dune sand.

౔৕ͷ෺ཧੑɹୈ 124 ߸ɹ (2013)48

͍͞ɽ͔͠͠ɼVSA ʹΑΔଌఆਫ਼౓͸ߴ͘ɼ͜͏ͨ͠ඇอ࣋‫ۂ‬ઢͷଌఆ͸ɼ౔ͷද໘ಛੑ΍ൺද໘ੵͷ‫ݕ‬౼ɼϚৗʹখ͞ͳώεςϦγε΋ଌఆՄೳͰ͋ΔʢFig. 7ʢbʣʣɽτϦοΫϙςϯγϟϧมԽʹͱ΋ͳ͏อਫ‫ߏػ‬ͷมԽɼ

DDI ଌఆ͸ɼ͍ͣΕͷ౔΋ WP4 ʹΑΔଌఆͱ΄΅Ұඍࡉͳ౔ཻࢠߏ଄มԽͷϚτϦοΫϙςϯγϟϧʹ‫΅ٴ‬கͨ͠ɽͨͩ͠ɼ‫ٵ‬ਫͷओ‫ۂ‬ઢ΍‫ٵ‬୤ਫͷ૸ࠪ‫ۂ‬ઢ͸ɼ͢Ө‫Ͳͳڹ‬ͷղ໌ʹ΋໾ཱͭ͜ͱ͕‫ظ‬଴͞ΕΔɽVSA Λ༻͍ͨ࿈ଓଌఆʹΑΓɼΑΓਫ਼౓ͷߴ͍ଌఆ͕ՄೳͱͳΔɽҰํɼVSA ͷ θ ͷઈର஋͸ɼҰ࿈ͷ VSAҾ༻จ‫ݙ‬ଌఆͱ͸ผʹଌఆ͢Δࢼྉͷॳ‫͋ظ‬Δ͍͸ଌఆऴྃ࣌ͷ‫ؚ‬ਫൺ w Λ‫ج‬४ʹͯ͠‫ٻ‬ΊΔɽଌఆʹ༻͍ͨ 2 g ͷࢼྉBarba, C., Marti, M., Carilla, J., Manich, A.M. and Coderch, L.

ͷ৔߹ɼVSA ͷଌఆൣғͰ‫·ؚ‬ΕΔਫ෼ͷॏྔ͸ 0.2 ∼(2013): Moisture sorption/desorption of protein ﬁbres. Ther-0.02 g ఔ౓Ͱ͋Δɽ͜Ε͸ɼࢼྉͷηϧ΁ͷग़͠ೖΕ΍

mochimica Acta, 552: 70–76.

࿍‫ס‬ॏྔଌఆͷࡍɼਫৠ‫ؾ‬ͷ‫࣪ٵ‬΍‫ס‬૩ͷӨ‫ڹ‬Λड͚Δ

Barbosa-Cánovas, G.B., Fontana, A.J., Schmidt, S.J. and Labuza,ྔͰ͋ΔɽͦͷͨΊɼVSA ʹ͓͚Δ௿ਫ෼ྖҬͷ θ ͷT.P. (2007): Water activity in foods. Blackwell Publishing Pro-ߴ͍ਫ਼౓ͷਪఆʹ͸ɼ‫ج‬४ͱ͢Δ w ͷଌఆʹ஫ҙ͕ඞཁͰ͋Δɽैདྷ͔Βɼதఔ౓ͷ h ྖҬʹ͸Ճѹ൘͕༻͍ΒΕ͖͕ͯͨɼಛʹ h < −1.5 × 104 cm ͷࢼྉͷฏߧ͕࣌ؒ‫ۃ‬Ίͯ௕͘ɼଌఆͷਫ਼౓΍࠶‫ݱ‬ੑɼॴ༻࣌ؒʹ໰୊͕ࢦఠ͞Ε͍ͯΔʢCampbell and Gee, 1986; Madsen et al.,

1986; Cresswell et al., 2008ʣɽͦͷͨΊɼՃѹ൘ͷଌఆ͸
h > −103 cm ͷྖҬʹ‫ݶ‬ఆ͢Δํ͕๬·͍͠ɽh > −103cm ͸‫ٵ‬Ҿ๏ͳͲͷํ๏ͱՃѹ൘๏ͷ૊Έ߹Θͤɼ·ͨh < −7.2 × 104 cm ͸ VSA ʹΑΓ࿈ଓతʹଌఆ͢Ε͹ɼ౔৕༹ӷͷೱ౓͕௿͍౔Ͱ͸ɼࢼྉͷཤྺ͕໌֬ͳਫ෼
อ࣋‫ۂ‬ઢΛɼਝ଎ʹɼ޿͍ྖҬͰଌఆՄೳͰ͋Δɽ͞Βʹɼ−5 × 104 < h < −5000 cm ͷཤྺͷ໌Β͔ͳࢼྉʹ

WP4 Λ༻͍Ε͹ɼVSA ͱՃѹ൘๏ͷଌఆΛิ‫͖Ͱ׬‬Δɽ

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Kirkham, M.B. (2005): Principles of soil and plant water rela-ͨɽैདྷ๏ͷ DVS Ͱ͸ mtrig = 0.01 % h−1 ɼ৽ͨʹ࠾༻

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͞ΕͨฏߧͱΈͳ͢ਫϙςϯγϟϧΛ࿈ଓଌఆ͢Δ DDI

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isotherm method to the standard saturated salt slurry method.
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49

Watanabe, K., Takeuchi, M., Osada, M. and Ibata, K. (2012):Yuan, X., Carter, B.P. and Schmidt, S.J. (2011): Determining theMicro-chilled-mirror hygrometer for measuring water poten-

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ཁࢫਫ෼‫ٵ‬୤ணଌఆ૷ஔ AquaLab VSA ͸ɼૹ෩ۭ‫ؾ‬ͷ࣪౓੍‫ڸͱޚ‬໘ྫྷ٫࿐఺ηϯαʔʹΑΓɼ࿈ଓతʹ‫ٵ‬ਫɼ͋Δ͍͸୤ਫաఔͷਫϙςϯγϟϧͱࢼྉͷॏྔΛࣗಈଌఆ͢Δɽຊ‫Ͱڀݚ‬͸ɼγϧτϩʔϜͷ౻ͷ৿౔ɼेউࠇϘΫ౔ɼௗऔٰ࠭࠭ͷ 3 छྨͷ౔Λର৅ʹɼVSA Λ༻͍ͯ −7.2 × 104 cm ͔Β−3.2 × 106 cm ͷ‫ס‬૩ྖҬͷਫ෼อ࣋‫ۂ‬ઢΛଌఆ͠ɼͦͷଌఆਫ਼౓΍ઃఆύϥϝʔλͷಛੑΛௐ΂ͨɽ
0.01 % h−1 ҎԼͷ‫ج‬४஋ mtrig Λ༻͍ͨ DVS ํࣜͰ͸ɼ౔தਫͷϙςϯγϟϧͱۭ‫౓࣪ؾ‬ͷे෼ͳฏߧ͕֬ೝ͞Εͨɽ·ͨɼ௿ਫ෼ྖҬͰ͸ද໘อਫ͕୎ӽ͢ΔͨΊɼฏߧͨ͠ॏྔ‫ؚ‬ਫൺ͸ɼ౔ͷ‫ס‬૩ີ౓ʹΑΒͣҰఆͰ͋ͬͨɽ৽ͨʹ։ൃ͞Εͨ DDI ํࣜͷଥ౰ੑΛɼDVS ํࣜͱͷൺֱʹΑΓ֬ೝͨ͠ɽDDI ํࣜͰ͸ɼૹ෩ۭ‫ؾ‬ͷྲྀྔ Qair Λ 100 mL min−1 ʹઃఆ͢Δ͜ͱͰɼ࿈ଓతͳਫ෼อ࣋‫ۂ‬ઢΛ 50h ఔ౓Ͱਫ਼౓ྑ͘ଌఆͰ͖ͨɽDDI ํࣜΛ༻͍Δͱɼ‫ס‬૩ྖҬͷਫ෼อ࣋‫ۂ‬ઢͷώεςϦγε΍૸ࠪ‫ۂ‬ઢΛ࠶‫ݱ‬ੑྑ͘ଌఆͰ͖Δ͜ͱ͕֬ೝ͞ΕͨɽΩʔϫʔυɿਫ෼อ࣋‫ۂ‬ઢɼਫϙςϯγϟϧɼ‫ڸ‬໘ྫྷ٫ࣜ࿐఺‫ܭ‬ɼDDI ํࣜɼώεςϦγε