We show experimentally that the sliding friction on sand is greatly reduced by the addition of some-but not too much-water. The formation of capillary water bridges increases the shear modulus of the sand, which facilitates the sliding. Too much water, on the other hand, makes the capillary bridges coalesce, resulting in a decrease of the modulus; in this case, we observe that the friction coef...

In this study, a grain-scale modelling technique has been developed to generate the capillary pressure-saturation curves for swelling granular materials. This model employs only basic granular properties such as particles size distribution, porosity, and the amount of absorbed water for swelling materials. Using this model, both drainage and imbibition curves are directly obtained by pore-scale...

It is known that the governing equations for the evolution of the envelope of weakly nonlinear capillary-gravity wave packets, the so-called Davey-Stewartson equation, admit dromion solutions in the limit of shallow water and strong surface tension, i.e., when kh≪1 and the Bond number (Bo) ≡T/ρgh^{2}>1/3 (where T is the surface tension coefficient and h the water depth). Here we show that capil...

Hysteresis in the saturation versus capillary pressure curves of neutrally wettable fibrous media was simulated with a random pore network model using a Voronoi diagram approach. The network was calibrated to fit experimental air-water capillary pressure data collected for carbon fibre paper commonly used as a gas diffusion layer in fuel cells. These materials exhibit unusually strong capillary...

capillary electrophoresis (ce) with indirect uv detection is an interesting analytical method for the analysis of drugs and pharmaceuticals. good and reproducible capillary quality is needed to develop robust methods and to facilitate method transfer in ce. it is widely accepted that preconditioning procedures are indispensable in capillary electrophoresis in order to achieve reproducibility of...

We examined the elution behavior of isoluminol isothiocyanate (ILITC)-labeled biomolecules (α-amino acids, peptides, and proteins) in an open-tubular capillary chromatography system using an untreated fused-silica capillary tube and a water-acetonitrile-ethyl acetate mixture carrier solution. Such an open-tubular capillary chromatography is called "tube radial distribution chromatography (TRDC...

INTRODUCTION There are no available data addressing the potential clinical risks of open-water swimming competitions. OBJECTIVE Address the risks of hypothermia and hypoglycemia during a 10-km open-water swimming competition in order to alert physicians to the potential dangers of this recently-introduced Olympic event. METHODS This was an observational cross-sectional study, conducted duri...

Salinization of soil is primarily caused by capillary rise from saline shallow groundwater orapplication of saline irrigation water. In this investigation, the transient state analytical modelwas modified to predict water uptake from saline shallow groundwater, actual cropevapotranspiration, soil water content, dry matter, seed yield and soil salinity under differentsaline groundwater depths, i...