Elasmobranchs such as the dogfish shark Squalus acanthius achieve osmotic homeostasis by maintaining urea concentrations in the 300- to 400-mM range, thus offsetting to some degree ambient marine osmolalities of 900-1,000 mosmol/kgH(2)O. These creatures also maintain salt balance without losing urea by secreting a NaCl-rich (500 mM) and urea-poor (18 mM) fluid from the rectal gland that is isot...

near-surface environment. Also, many of the complicating effects found in the near-surface environment will Approaches for estimating liquid flux in the shallow (0–2 m) vadose be damped or eliminated with increasing depth. For zone are hindered by the high degree of spatial and temporal variability present near the land surface. It is hypothesized that high-frequency these reasons, flux measure...

in this research, process asymmetric polyetherimide hollow fiber membranes using ethanol (0, 2 and 4 wt%) as non-solvent additive in the polymer dope via phase inversion method were fabricated. aqueous solution of 1-methyl-2-pyrrolidine (nmp) (90%) was applied as a bore fluid to avoid inner skin layer formation and water was used as the external coagulant. the morphology of fabricated membranes...

in this study, a mixed matrix polyethersulfone/iron-nickel oxide nanoparticle nanofiltration membrane was prepared by the solution casting technique. polyvinylpyrrolidone was also used as a membrane pore former in membrane fabrication. the effect of iron-nickel oxide nanoparticles concentration in the casting solution on the membrane structure and performance was investigated. scanning optical ...

The resistances to liquid water transport in the soil and plant were determined directly and simultaneously from measurements of soil, root, and leaf water potentials and the flux of water through the soil-plant system to the sites of evaporation in the leaf. For soybean (Merr.) transporting water at a steady rate, water potential differences between soil and root were smaller than between root...

In this study, local area water content distribution under various gas purging conditions are experimentally analyzed for the first time. The local high frequency resistance (HFR) is measured using novel micro sensors. The results reveal that the liquid water removal rate in a membrane electrode assembly (MEA) is non-uniform. In the under-the-channel area, the removal of liquid water is governe...

Membranes that separate oil-water mixtures based on contrasting wetting properties have recently received significant attention. Separation of nanoemulsions, i.e. oil-water mixtures containing sub-micron droplets, still remains a key challenge. Tradeoffs between geometric constraints, high breakthrough pressure for selectivity, high flux, and mechanical durability make it challenging to design ...

4 A novel method for irrigation with saline water uses a polymer membrane, formed 5 into a tube, to treat and distribute the water simultaneously. The flux of water across 6 the membrane occurs by the process of pervaporation, during which a phase change from 7 liquid to vapor occurs. Thus water arrives in the soil in vapor phase. The experimental 8 results presented in this paper demonstrate t...

In the present study, mixed matrix PES/zeolite nanoparticles nanofiltration membranes were prepared via the solution casting technique. The effect of zeolite concentration on the PES membrane performance and its properties was studied. Cross-sectional scanning electron microscope (SEM) observations showed that the porosity in the membrane sub-layer was increased with addition of zeolite into th...

• Membrane structural parameters were evaluated for use in predicting water flux. • Membrane constant containing non-coupled membrane properties was introduced. • Membrane constant requires simple measurements and inexpensive analytical equipment. • Membrane constant correlates well with experimental water flux. • Comprehensive collection of MD membrane properties and water fluxes made availabl...