polyvinylidene fluoride/polyvinylpyrrolidone (pvdf/pvp) hollow fiber membranes were fabricated by dry-jet wet-spinning process. the correlated effects of the air gap length and pvp concentration ((1) the air gap length effect at the low and high pvp concentration in the dope solutions, as well as (2) the effect of the pvp concentration at the same air gap length) on the cross-section structure ...

this paper investigates hollow and porous alumina nanospheres that were previously synthesized to be used for the dehydration of methanol to dimethyl ether (dme). as hollow nanostructures possess characteristics such as low density and high surface to volume ratio, their catalytic activity between hollow and porous structure is compared. for this purpose, three most important parameters (acidit...

Abstract Egyptian Chorisia hollow fibers have been blended with cotton waste, polyester and raw bamboo at various ratios weft counts using open-end spinning. The fabrics of hybrid composites were subjected to atmospheric plasma, pectinase, lipase enzyme treatments, as well the substitution all hazardous chemicals, sustainable alternatives traditional alkaline scouring. impacts treatments on hol...

We are developing a new method using ultrasonic longitudinal and torsional vibration of a hollow-type stepped horn for hole machining. We foresee that the equipment can be simplified and miniaturized. In this paper, ultrasonic vibration sources of a hollow-type stepped horn without a diagonal slits vibration converter and with a diagonal slits vibration converter are used. The longitudinal and ...

Tapered columns are a type of column that is used for different purposes, including architectural purposes or structural needs to take into account the changes occur moments along with height column. For example, in highway bridges, tapered reduce number transmitted base and from there foundation. This research studied analysis short reinforced concrete variable cross-sections linear manner by ...

The morphological features of the cell wall, plasma membrane, protoplasmic constituents, and flagella of Acetobacter suboxydans (ATCC 621) were studied by thin sectioning and negative staining. Thin sections of the cell wall demonstrate an outer membrane and an inner, more homogeneous layer. These observations are consistent with those of isolated, gram-negative cell-wall ghosts and the chemica...

This paper describes the results of an experimental study to verify proposed design requirements for eccentrically braced frame links with hollow rectangular i.e., tubular cross sections. Twelve primary link specimens and two supplementary links that have different end connections are tested. Three cross sections and four normalized link lengths are considered. Two of the cross sections have we...

We developed a process to fabricate 150-700 nm monodisperse polymer particles with 100-500 nm hollow cores. These hollow particles were fabricated via dispersion polymerization to synthesize a polymer shell around monodisperse SiO(2) particles. The SiO(2) cores were then removed by HF etching to produce monodisperse hollow polymeric particle shells. The hollow core size and the polymer shell th...