title: Wettability determined by capillary rise with pressure increase and hydrostatic effects.
abstract: Capillary rise is the basis of some methods that are widely applied for the determination of contact angles as well as wettabilities of small particles. The equivalent hydraulic radius r(d) in the Classical Washburn equation is assumed to be particle-specific. But it seems that r(d) is not always constant when the type of liquids is different. The new equation with the pressure increment and the hydrostatic effects are theoretically derived based on the Washburn equation, so contact angles of small particles can be measured experimentally independently of r(d). The result shows the validity of the proposed method, and therefore, it becomes possible to accurately measure the wettability of small particles.
authors.affiliation: Engineering Research Center for Cold and Arid Regions Water Resource Comprehensive Utilization of Ministry of Education, School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China.
authors.forename: Bigui
authors.initials: B
authors.lastname: Wei
authors.forename: Qing
authors.initials: Q
authors.lastname: Chang
authors.forename: Caiyun
authors.initials: C
authors.lastname: Yan
mesh_terms: D000465:Algorithms; D002627:Chemistry, Physical / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D006874:Hydrostatic Pressure; D010316:Particle Size; D015203:Reproducibility of Results; D017155:Wettability