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 ...

The importance of adventitious air leakage under normal operational conditions and its reduction in order to save energy is highlighted by the relvant building standards of many countries. This operational leakage is often inferred via the measurement of air permeability, a physical property of a building that indicates the resistance of its fabric to airflow. A building’s permeability is the m...

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 ...

Mercury intrusion porosimetry (MIP) measurements are widely used to determine pore throat size distribution (PSD) curves of porous materials. The pore throat size of porous materials has been used to estimate their compressive strength and air permeability. However, the effect of sample size on the determined PSD curves is often overlooked. In pursuit of a better understanding of the effect of ...

OBJECTIVES The high values of thermal resistance (Rct) and/or vapor resistance (Ret) of chemical protective clothing (CPC) induce a considerable thermal stress. The present study compared the physiological strain induced by CPCs and evaluates the relative importance of the fabrics' Rct, Ret, and air permeability in determining heat strain. METHODS Twelve young (20-30 years) healthy, heat-accl...

The presence of capillary pores and air voids influences concrete permeability to a large extent. Concrete density is inversely proportional to its porosity. The ingress of aggressive agents into the pore structure is responsible for various durability problems in concrete structures. Therefore, a durable concrete should have low permeability. Permeability of concrete increases with the increas...

The aerosol penetration efficiency and quality factor for three Chemical Biological Radiological protective fabrics were evaluated using a particle counting technique. Both parameters characterise aerosol penetration through tested material; the latter accounts for the effect of fabrics air permeability. The overall and size dependent penetrations of 0.03–3 μm sized Sodium Chloride (NaCl) and D...