Worsted Spinning

However, as stated above, the description of fiber fineness by reference to its diameter tends to be in the minority, and usually fiber fineness is expressed in terms of linear density. There have been many systems of yarn measurement throughout the world, not to mention the variations in the cotton spinning, worsted, and woollen industries, but for present purposes only the SI system will be used (tex = g km), as this is universally recognized and is the system employed in international standards after 50 years of gestation it is now being widely used across the globe. 

Flyer spinning n. A method of spinning by means of a driven flyer. It is used primarily for spinning worsted and coarser yarns. Also see flyer (1). 

Woolen spinning is thus a very short sequence compared to worsted processing. Woolen yams are economically uncompetitive with worsted yams even at relatively coarse yam counts, a result of the yams being virtually made on the carding machine, the expense of the much larger card used, the low dehvery speed, and the very low card production in spinning fine yams, resulting from the low deUvery speed. 

Today, controlling the mind of what is perceived as the enemy has risen to new heights. While propagandists and spin doctors are the more visible tools, there is a much more sinister understanding of how advances in technology can turn any human being into a kind of slave. The worst part of it all is that many of those so enslaved are so well conditioned to their state of misery that they accept the yoke with little struggle. 

Particular problems are encountered where the detector / couples to more than one S spin since the assembly of S spins can act as a unit. The result is false coherences relating the / spin to the sums or differences of the frequencies of the S spins and intensity distortions. In the worst case this can result in an HMQC spectrum in which only coherences resulting from multiple S spin transitions are seen. None of these transitions occur at the chemical shift of the S spin (Figure 12). 

Spinning lubricants for semi-worsted and woollen system especially suitable for carpet- and upholstery yarns free of mineral oil, antistatic. 

Fig. 12. Coherence-transfer functions under ideal isotropic-mixing conditions for a system of three coupled spins, which represents a typical H spin system of serine in DjO, with = 4.5 Hz, Jafi = 9 Hz, and = -15 Hz. In the simulations represented by the solid lines, the two-spin approximation is assumed to be valid. The dashed curves result when the exact three-spin case is calculated. The a-/3 transfer function demonstrates the worst case, in which the two-spin approximation predicts a maximum at the same time that the exact three-spin isotropic mixing transfer function reaches a minimum. (Adapted from Remerowski et al., 1989, courtesy of Taylor Francis.)...

In Table 4 the results of calculations of the FC contribution to heteronu-clear spin-spin coupling constants for HF, H2, NH3 and CH4 molecules for different types of exchange-correlation functional, basis sets, grid quality, values of perturbation parameter A in the FPT approach and choices of centre of the perturbation are presented. The most remarkable example in this Table, and the worst from the point of view of the agreement obtained with experimental data, is the HF molecule. As we will show later this molecule is a typical example of the calculations of the one-bond coupling of an F atom with C or H atoms. 

The one-bond spin-spin coupling with the F nucleus is the worst case which we have found up to now. In general, our experience is that the results go from good to worse in the series H, C, N, 0, and F and likely depend on the number of lone pairs at the nucleus and therefore on the ability of an exchange-correlation functional to describe spin-density... 

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