Investigations were made of rotary resonance recouplings (R) of chemical shift anisotropy ~CSA!, heteronuclear dipolar ~HTD!, and homonuclear dipolar ~HMD! couplings involving half-integer quadrupolar nuclei under magic-angle sample spinning condition. Under rotary resonance conditions provided by a low amplitude rf field and a high spinning speed, the spectrum of the central transition coheren...

A passive false twist unit (spiral) has been developed to assist with the handling lowstrength slivers on a high speed-spinning machine with a high-speed feed. In the first trial, a falsetwist simulator device was constructed to determine whether the passive false twist unit can be usedon high speed feeding with different can distance from the feeding device. In the second trial, theeffects of ...

This paper surveys recent progress in fiber spinning technology for reducing polarization mode dispersion with the focus on theoretical understanding of fiber spinning mechanism and features of spun fibers, as well as their applications in fiber spin profiles designs. First, a brief introduction to the requirements of fiber PMD for high-speed optical fiber communications systems is given. Furth...