Holding magnet

One such index is line frequency, which provides indications of instability. Modulations, or harmonics, of line frequency may indicate the motor s inability to find and hold magnetic center. Variations in line frequency also increase the amplitude of the fundamental and other harmonics of running speed. 

Magnetic yokes in permanent magnet devices, such as lifting and holding magnets, loudspeakers... 

If there are inserts made from magnetizable materials, the fixation can be done using so-called holding magnets. 

Chu WC, Yeung DT, Lee KH et al (2005) Feasibility of morphologic assessment of vascular and biliary anatomy in pediatric liver transplantation all-in-one protocol with breath-hold magnetic resonance. J Pediatr Surg 40 1605-1611... 

Alternatively, ions of any one selected m/z value can be chosen by holding the magnetic field steady at the correct strength required to pass only the desired ions any other ions are lost to the walls of the instrument. The selected ions pass through the gas cell and are detected in the singlepoint ion collector. If there is a pressure of a neutral gas such as argon or helium in the gas cell, then ion-molecule collisions occur, with decomposition of some of the selected incident ions. This is the MS/MS mode. However, without the orthogonal TOF section, since there is no further separation by m/z value, the new ions produced in the gas cell would not be separated into individual m/z values before they reached the detector. Before the MS/MS mode can be used, the instrument must be operated in its hybrid state, as discussed below. 

The solid tenaciously holds a small amount of chloroform which can be detected by proton magnetic resonance (S 7.25). Vacuum drying overnight at 60 removes this impurity. 

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