A theory of sideband intensity is derived by expanding into a Taylor series the free induction decay observed under magic angle spinning (MAS). According to this procedure, the free induction decay signal is completely represented by a basis of irreducible tensors from rank zero to rank infinity. After averaging over all orientations, only the zero-order irreducible tensors contribute to the si...

Regarding the importance of ring spinning method among spinning systems, great potentials exist for research about on the improvement of the quality and properties of ring spun yarn. This study aims to improve yarn quality by changing the shape and dimensions of spinning triangle through forming a groove in the middle zone of the front darfting roller with a curvature of 5 to 7 mm. For the to...

Several different amplitude-modulated two-dimensional high-resolution methods, based on MQMAS and STMAS, are compared. They include 3QMAS, 5QMAS, DQ-STMAS, and DQF-STMAS experiments. A new method, called t1-split-STMAS, is also proposed for spin-3/2 nuclei. The comparison is performed in terms of isotropic resolution and spectral-width, efficiency, and sensitivity to magic-angle offset and spin...

Crocodilians, including the alligator (Alligator mississippiensis), perform a spinning maneuver to subdue and dismember prey. The spinning maneuver, which is referred to as the ;death roll', involves rapid rotation about the longitudinal axis of the body. High-speed videos were taken of juvenile alligators (mean length=0.29 m) performing death rolls in water after biting onto a pliable target. ...

In the manufacture of yarn, predicting the effect of changing production conditions is vital to reducing defects in the end product. This study compares, for the first time, non-linear regression and artificial neural network (ANN) models in predicting 10 yarn properties shaped by the influence of winding speed, quenching air temperature and/or quenching air speed during production. A multilaye...

Bimetallic nanorods are propelled without chemical fuels in megahertz (MHz) acoustic fields, and exhibit similar behaviors to single-metal rods, including autonomous axial propulsion and organization into spinning chains. Shape asymmetry determines the direction of axial movement of bimetallic rods when there is a small difference in density between the two metals. Movement toward the concave e...