Relative humidity effects on contact angle and water drop penetration time of hydrophobized fine sand(Soil Physics)

スポンサーリンク

概要

• 論文の詳細を見る

• The purpose of this study was to determine the effects of ambient relative humidity (RH) on contact angle and water drop penetration time (WDPT) using a series of sand samples hydrophobized with stearic acid. The contact angle was estimated using the sessile drop method. The contact angle increased first sharply and then slightly with increasing stearic acid content up to about 5.0g kg^<-1>. The contact angle did not change with increasing stearic acid content above 5.0g kg^<-1>. The contact angle increased with increasing RH from 33 to 94%. The RH did not affect the contact angle of samples with a stearic acid content above 5.0g kg^<-1>, where the particles were considered to be completely coated by hydrophobic organic material. The contact angle increased with increasing RH in sands partially coated with hydrophobic material, which might have resulted from an increase in adsorbed water molecules on the remaining high-energy mineral surfaces. The WDPT increased with increasing RH. The higher the RH, the lower the stearic acid content at which extreme repellency (WDPT≥3600s) appeared. Samples with a contact angle below 75° or with surface free energy above 72mN m^<-1> (equivalent to the surface tension of water) were non-repellent (WDPT<1s). Samples with a contact angle above 90° or with surface free energy below 50mN m^<-1> were extremely repellent. There was no effect of RH on the relationship between WDPT and contact angle (or surface free energy), indicating that the effect of RH was comparable on both measurements.

著者

• KARUBE Jutaro

  Faculty of Agriculture, Ibaraki University

• LEELAMANIE D.A.L.

  United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology

• YOSHIDA Aya

  Graduate School of Agriculture, Ibaraki University

• Yoshida Aya

  Graduate School Of Agriculture Ibaraki University

• Karube Jutaro

  Faculty Of Agriculture Ibaraki University

• Leelamanie D.a.l.

  United Graduate School Of Agricultural Science Tokyo University Of Agriculture And Technology

• Leelamanie D.

  United Graduate School Of Agricultural Science Tokyo University Of Agriculture And Technology

関連論文

• Effects of hydrophobic and hydrophilic organic matter on the water repellency of model sandy soils(Soil Physics)
• Time dependence of contact angle and its relation to repellency persistence in hydrophobized sand(Soil Physics)
• Relative humidity effects on contact angle and water drop penetration time of hydrophobized fine sand(Soil Physics)
• Characterizing water repellency indices : Contact angle and water drop penetration time of hydrophobized sand(Soil Physics)
• Effects of organic compounds, water content and clay on the water repellency of a model sandy soil(Soil Physics)
• Clay effects on the contact angle and water drop penetration time of model soils(Soil Physics)
• Material cycles in Asia : especially the recycling loop between Japan and China
• Water-dependent repellency of model soils as affected by clay(Soil Physics)
• Drop size dependence of soil-water contact angle in relation to the droplet geometry and line tension(Soil physics)
• Soil-water contact angle as affected by the aqueous electrolyte concentration(Soil physics)
• Stability analysis of aggregates in relation to the hydrophobicity of organic manure for Sri Lankan Red Yellow Podzolic soils(Soil physics)

もっと見る 閉じる

スポンサーリンク