Push-pull arrangement

Figure 4.14 Three different electrooptic waveguide devices [1] (a) Mach-Zehnder modulator with push-pull arrangement of the electrodes, (b) electrically controlled directional coupler, (c) coupler with phase-reversal electrodes.

Low torsional barriers in combination with strong steric interactions between donor and acceptor groups in push-pull ethylenes have in several cases been demonstrated to cause permanently twisted double bonds, in which a planar arrangement of substituents at the double bond may represent an energy maximum. 

Essential Question If clay can be pushed, pulled, bent, and twisted, how are atoms and molecules arranged within... 

Since the vibrational spectra obtained for these two structures (iii) are very similar, we will describe in detail only the results obtained for the stacking geometry (Figure 4.17). This architecture seems to be a better model mimicking the arrangement of strongly interacting dimers as observed in crystals of similar push-pull polyenes [2],... 

This mast assembly consists of two ball screw arrangements to Impart linear drives to the serving shoe push/pull member and the links... 

The push-pull output driver overcomes the slew limitation and need for an external current source of the source follower output by providing two opposing source follower circuits that together provide both an active source (pull-up) and sink (pull-down) to drive the signal through the output cable. This arrangement, normally implemented with a complimentary pair of MOSFETs (p- and n-channel devices), significantly reduces the static power of the output driver. 

The so-called hyperbar vacuum filtration is a combination of vacuum and pressure filtration in a pull—push arrangement, whereby a vacuum pump of a fan generates vacuum downstream of the filter medium, while a compressor maintains higher-than-atmospheric pressure upstream. If, for example, the vacuum produced is 80 kPa, ie, absolute pressure of 20 kPa, and the absolute pressure before the filter is 150 kPa, the total pressure drop of 130 kPa is created across the filter medium. This is a new idea in principle but in practice requires three primary movers a Hquid pump to pump in the suspension, a vacuum pump to produce the vacuum, and a compressor to supply the compressed air. The cost of having to provide, install, and maintain one additional primary mover has deterred the development of hyperbar vacuum filtration only Andrit2 in Austria offers a system commercially. 

Figure 5.3. Basic equipment arrangements of pneumatic conveying systems, (a) Vacuum system with several sources and one destination, multiple pickup (b) pressure system with rotary valve feeder, one source and several destinations, multiple discharge (c) pressure system with Venturi feed for friable materials (d) pull-push system in which the fan both picks up the solids and delivers them [after F. J. Gerchow, Chem. Eng. [17 Feb. 1975, p. )].

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