Fibre fineness

Most textile fibres are in the range of 2 to 20 dtex, with diameters, depending on density, between about 10 and 50 ym. Polyester microfibres have been developed for apparel textiles, including leather-like products. With suitable precautions, direct melt-spinning can be taken down to 0.4 dtex (6 ym);

conjugate melt-spinning followed by splitting to 0.1 dtex (3 ^m); and islands-in-a-sea spinning, in which an enveloping material is dissolved away, to 10-4 dtex (0.1 pm or 100 nm). The last of these could be called a nano-fibre, but the development of electro-spinning makes finer fibres possible. As a goal, 1 nm would correspond to about 10-8 dtex and would have few molecules in its cross-section

The fineness of fibres is a determinant of barrier performance. A closely packed assembly of fibres will have small spaces2 between fibres, which are less than the fibre diameter, thus inhibiting particulate entry. The large surface area is effective in absorbing chemicals: 1 kg of a 100 nm diameter fibre would have a surface area of about 30,000 m (200 x 150 m); at 1 nm the figure would be 3 x 106m2 (2 x 1.5 km).

End of Days Apocalypse

End of Days Apocalypse

This work on 2012 will attempt to note them allfrom the concepts andinvolvement by the authors of the Bible and its interpreters and theprophecies depicted in both the Hopi petroglyphs and the Mayan calendarto the prophetic uttering of such psychics, mediums, and prophets asNostradamus, Madame Blavatsky, Edgar Cayce, and Jean Dixon.

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