Nanofiber membranes are widely employed to prepare composite filter media. The traditional method of hot pressing may damage the structure nanofiber membrane, and thus increase pressure drop through filter. In this study, three-dimensional PET/TPU (polyethylene terephthalate/thermoplastic polyurethane) filters (PET/TPU-CNF) with beads-on-string were fabricated by one-step co-electrospinning. Be...

In this paper, a novel technique for the design of two-channel Quadrature Mirror Filter (QMF) banks with linear phase in frequency domain is presented. To satisfy the exact reconstruction condition of the filter bank, low-pass prototype filter response in pass-band, transition band and stop band is optimized using unconstrained indirect update optimization method. The objective function is form...

A sodium silicate-based chemical grout was used in the Karkheh dam site in order to examine the performance of the chemical grouting technique for stabilization of the dam's filter material. Karkheh, an embankment dam with the reservoir capacity of about 7.4 billion cubic meter at the maximum water level, is the largest dam in Iran. The grouting works performed at the dam site, were part of the...

Fine-grained particle systems build up a highly consolidated and thin layer on the filter medium cause high cake resistance. The objective of novel thin-film filtration process is an effective mechanical separation these using membranes vacuum drum filter. stability membrane evaluated since roller required for discharge performance compared with that commonly used cloth. Analyses reveal surface...

A two-layer membrane filtration (MF) medium (injury-mitigating MF [IM-MF]) and a procedure for the enumeration of injured fecal coliforms are described. These procedures included the addition of glycerol and acetate plus reducing agents to both layers of a two-layer medium and rinsing of the filter with a rich resuscitation medium. Some changes in incubation time and temperatures were used. Thi...

Cultures containing mixed flora from raw milk were heated at 62.8 C for 15, 20, 25, and 30 min. Dilutions were filtered through membrane filters, and the filters were incubated on Trypticase soy broth (TSB) and on TSB plus NaCl (TSBS). The TSB count indicated the total population which survived heating and included injured and uninjured cells. The colonies on TSBS indicated the uninjured cells ...

Particle emissions into the atmosphere can cause extensive damage to environment and human health. To improve efficiency in collection of submicronic particles, new filtration media appeared on market due textile technologies equipment, such as filter developed with polytetrafluoroethylene (PTFE) membranes; however, these are more expensive. A coating technique called precoating is a economical...

The membrane filter, also known as molecular filter, is valuable for its ability to permit passage of large volumes of fluid and yet retain on its surface particles of bacterial size. The history of its development and some of its properties have been reviewed by Goetz and Tsuneishi (1951). Other properties and specifications are available from the manufacturers.3 At present details of manufact...