Pore Characterization in Cross Section of Yellow Poplar (Liriodendron tulipifera) Wood

Abstract

This study was conducted to analyze the pore structure of Yellow poplar. Cross-sectional surfaces of heartwood and sapwood of Yellow poplar (Liriodendron tulipifera) were observed by SEM, and the true density of the heartwood, intermediate wood and sapwood were measured by gas pycnometery, while gas permeability and pore size of heartwood, intermediate wood and sapwood were measured by capillary flow porometery. The pores were classified as through pore, blind pore and closed pore.It was determined that the permeability was increased due to the content and size of through pore being increased although the total porosity of specimen showed slight difference from pith to bark. The content of through pore porosity was 33.754 % of heartwood and 47.810 % of sapwood, showed an increasing trend from pith to bark, however, those for the blind pore porosity and closed pore porosity were 27.890 % and 19.492 % for heartwood and 19.447 % and 4.660 % for sapwood, showed a decreasing trend from pith to bark.The max pore size of specimens was increased by about 5 times from 5.927 μm to 31.334 μm, and mean flow pore size was increased by about 315 times from 0.397 μm to 12.437 μm from pith to bark.

Investigation of Sound Absorption Properties of Heat-Treated Indonesian Momala (Homalium foetidum (Roxb.) Benth.) and Korean Red Toon (Toona sinensis (A. Juss.) M. Roem.) Cross Sections

“…Pore size was measured by capillary flow porometry [32][33][34] using the standard method of ASTM F-316 [35]. This method's main characteristic is that it measures the constricted segments of only the through-pores to measure only the pores that affect permeability [25,31,[34][35][36][37][38][39]. The same equipment used for gas permeability was used to measure pore size.…”

Improving the Sensitivity of Nanofibrous Membrane-Based ELISA for On-Site Antibiotics Detection

“…Closed pores are formed in the middle of the membranes without access to out layers, which have no contribution to diffusion or partition of chemicals into the membranes. 15 Our recent study of diffusion of large molecules through nanofibrous membranes found that only when the measured pore size of the membrane is close to 1000 times larger than diffusant molecules, a regular diffusion pattern of the molecules could be observed through the membrane. 16 Such results indicate that the measured pore sizes could not represent the real pores of the nanofibrous membranes contributing to the diffusion of large molecules, which is defined as effective pores of the membranes.…”

“…The through pores can allow particles to penetrate through the membrane, and the blind pores have closed ends that can block the diffusion of the particles. Closed pores are formed in the middle of the membranes without access to out layers, which have no contribution to diffusion or partition of chemicals into the membranes . Our recent study of diffusion of large molecules through nanofibrous membranes found that only when the measured pore size of the membrane is close to 1000 times larger than diffusant molecules, a regular diffusion pattern of the molecules could be observed through the membrane .…”

“…The pores along this direction of the membrane could have three different types, through pores, blind pores, and closed pores. 15 The through pores can allow particles to penetrate through the membrane, and the blind pores have closed ends that can block the diffusion of the particles. Closed pores are formed in the middle of the membranes without access to out layers, which have no contribution to diffusion or partition of chemicals into the membranes.…”

“…The pore sizes and distributions in the membranes vary significantly depending on different directions, mainly in the vertical direction. The pores along this direction of the membrane could have three different types, through pores, blind pores, and closed pores . The through pores can allow particles to penetrate through the membrane, and the blind pores have closed ends that can block the diffusion of the particles.…”