Drift tube cylindrical

In an article on drift tubes of comparatively large size and a cylindrical geometry [54], Buryakov and Kolomiets combined a multi-capillary column [55,56] with the analyzer to obtain measurements and quantitative response curves with a GC-DMS configuration. 

Cylindrical drift tubes as described commonly require a machine shop to prepare components and technical experience to assemble the many parts into a drift tube. This in addition to the material and production costs can be seen as restrictions in innovations of drift tube designs and development of IMS methods. To speed drift... 

FIGURE 6.5 Drift tubes for FAIMS or DMS including the configuration commercialized by Thermo Fisher Scientific (a) with a cylindrical shape (with permission from Thermo Fisher Scientific) the first small planar design commercialized by Sionex, Incorporated (b) (from Miller et al., A novel micro-machined high field asymmetric waveform ion mobility spectrometer, Sens. Actuators B 2000 with permission) and the microfabricated, very small structures of the ultraFAlMS (c) manufactured by Owlstone Nanotechnology (from Owlstone White Paper, 2006). 

Giles and Grimsrnd described an instrument designed specifically for the study of ion/molecule reactions [35]. The cylindrical drift tube was large, 40 cm long and 9 cm in diameter, and the moveable ion source allowed facile change in drift length. 

The ion beam is brought to a focus at the intermediate slit, which is positioned 3/4 of the way through a cylindrical metal tube hereafter refered to as the drift tube. The beam then enters an 81.5 electrostatic analyser (ESA) which may be set to transmit either the parent ions, or fragment ions produced by dissociation of the parent beam. Those ions transmitted by the ESA may be detected on the second off-axis electron multiplier, or on a Faraday cup. 

The utility of the concept of aerosol particle electrical drift velocity can be shown by using it to estimate the theoretical efficiency of an electrostatic precipitator. For simplicity it is assumed that the collector is cylindrical, having a radius R (although this assumption does not affect the results), and that an aerosol is uniformly distributed across the entrance of the collector. In addition, turbulent flow in the collector is assumed such that the uncollected aerosol remains uniformly distributed at any distance from the entrance of the tube. If the electrical drift velocity is constant, the chance of a particle 4> being collected in a time At is... 

Migration (drift) velocity = 0.52 ft/s Cylindrical tube diameter = 6 in. 

The linear accelerator (also called LINAC) is a series of cylindrical tubes, which are alternately connected to a high-frequency generator, as shown in Rig. 50.17. The charged particles are accelerated in the gaps between the tubes and then they drift inside the tube in a field-free region. While the particles are inside the tube, the direction of the electric field is reversed. If the length of tubes is increased in proportion to the particle speed, the particles will always arrive at the next gap at the correct phase of the RF voltage. 

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