Abstract Trapped or residual air (or gas) is known to affect the multiphase hydraulic properties of both soils and rocks. impact many vadose zone hydrologic applications such as infiltration flow in capillary fringe, but also a major issue affecting recoverable oil reserves. Although studies have focused on relationship between porosity trapped gas saturation ( S gt ) sandstones, far fewer been...

This study focused on phase separation of activated sludge mixed liquor by flat-sheet membranes of polytetrafluoroethylene (PTFE). A 20 liter working volume lab-scale MBR incorporating immersed PTFE flat-sheet membrane modules with different pore sizes (0.3, 0.5 and 1.0 μm) was operated for 19 days treating a synthetic wastewater. The experiment was interrupted twice at days 5 and 13 when the m...

M. E. Zeynali [email protected] Petrochemical Synthesis Group, Petrochemical Faculty, Iran Polymer and Petrochemical Institute (IPPI), P. O. Box: 14965/115, Tehran, Iran, Abstract In this study the diffusion coefficients for reaction components were determined for unimodal and bimodal pore size distribution and assuming transitional diffusion regime using a more realistic, Stewart-Johnson, m...

Underground rocks usually have complex pore system with a variety of pore types and a wide range of pore size. The effects of pore structure on elastic wave attenuation cannot be neglected. We investigated the pore structure effects on P-wave scattering attenuation in dry rocks by pore-scale modeling based on the wave theory and the similarity principle. Our modeling results indicate that pore ...

Bi2Mn2O7 nano-powders were synthesized via a stoichiometric 1:1 Bi:Mn molar ratio hydrothermal method at 180 °C for 48 h in a 1M NaOH aqueous solution; and solid state method, using Bi(NO3)3.5H2O and MnO2 as raw materials. The synthesized materials were characterized by powder X-ray diffraction (PXRD) technique. Also, the rietveld analysis was done in FullProf in profile matching mode. It was f...

The productive fusion pore in membrane fusion is generally thought to be toroidally shaped. Theoretical studies and recent experiments suggest that its formation, in some scenarios, may be preceded by an initial pore formed near the rim of the extended hemifusion diaphragm (HD), a rim-pore. This rim-pore is characterized by a nontoroidal shape that changes with size. To determine this shape as ...

In this work, a simple and effective way to modify the support surface is developed and a nanostructure ceramic support to facilitate deposition of a defect-free overlying micro and meso (nano) porous membrane is obtained. To achieve high performance nanocomposite membranes, average pore size of outer surface of support was reduced by dip-coating in submicron and nano α-alumina slurries. In...