Movable electrode

Most furnace shells are short vertical cylinders but may also be triangular, elliptical, or rectangular in plan view. Single-phase furnaces may have one or two movable electrodes. Three-phase furnaces usually have three movable electrodes, but some have six (three paks, two electrodes for each phase). 

One of the most important parts of the FTIR technique is the movable electrode in order to allow proper diffusion of species to and fro... 

Fig. 7.3.2 shows the principle of the capacitive sensor. The electrode consists of a fixed electrode and a movable electrode formed in the thin-walled diaphragm. When a pressure is applied, the diaphragm is distorted and the width of the gap between the above two electrodes is changed. The sensor retrieves the change in the gap width as the change in capacitance. The change in capacitance AC is expressed by the following equation. 

A much higher efficiency is reached in the apparatus developed by V. Kohlschiitter [5] (see Fig. 340), comprising an arc furnace with vertical electrodes. The bottom electrode has an indentation for the metal to be volatilized. The arc is struck between the metal and the top (movable) electrode. Usually the vaporization proceeds very smoothly if the metal is the anode. The optimum conditions for the operation of the arc and for removal of the vapors from the electrodes vary somewhat from metal to metal. 

Fig. 7 Schematic diagrams of the microchip electrophoretic system with the movable contactless-conductivity detector (A) along with a detailed design of the movable electrode system top (B) and bottom (C) views as well as cross-sectional views without (D) and with (E) the PMMA separation chip, (a) Run buffer reservoir, (h) sample reservoir, (c) unused reservoir, (d) movable electrodes, (e) separation chaimel, (f) sample waste reservoir, (g) PMMA chip, (h) conductive silver epoxy, (0 PVC clamps, (/ ) copper wires, (k) aluminum foil electrodes, and (/) Plexiglas plate (Reprinted with permission from Ref. [9])...

Fig. 6 (a) Top and (b) side view of a PMMA electrophoresis microchip with a sharp-tip inlet (h) and a movable electrode system (c) for the contactless conductivity detection and (c) a photograph of the final PMMA microchip with a sharp inlet tip. (a) PMMA chip, (b) hole linked to the buffer solution, (c) movable electrode system, (d) separation channel, (e) hole for the high-voltage power electrode, (f) platinum wire high-voltage electrode, (g) buffer vial, (h) sharp inlet tip, (i) sample solutions vial, (j) buffer reservoir, (k) pipette tip for buffer reservoir, (1) buffer solution (Reproduced with permission from [6])... 

The setup of the electrostatic drive is illustrated in Figure 18.14(b). The fixed electrodes consist of two thick poly-Si layers, separated by an oxide layer and can be connected to the deflection voltages. The movable electrodes are constructed of one layer... 

Spread films can be characterized by surface potentials as well as by force-area measurements. In this type of measurement the change of the electrical potential difference between the substrate solution and air produced by the compression of the spread film is studied. The experimental arrangement generally used consists of a movable electrode above the surface of the film, a reversible electrode in the substrate solution and the proper external circuit which permito the measurement of the potential difference between the air and the substrate solution. Descrip-... 

Gross 337] and Gcmant [338] subsequently pointed out that there will be some error in this method due to the interference between the electret surface and the movable electrode. When the electrode is lifted, the interference will be inaeased. Treating the system u a two-layer capacitor, Gross calculated the electric field ( ) in the air gap as... 

Electrobrushes/movable electrodes are being developed for specific decontamination applications. 

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