Electrode connector

Simplified schematics of a gliding arc-type plasma reformer. 1 = Electrodes, 2 = discharges, 3 = vessel with insulation, and 4 = electrode connectors. 

The pH meter can be analog, digital, or, as mentioned earlier, attached to a computer. As shown in Figure 9.6, each electrode has a different connector illustrating the need to match electrode connector with meter. Regardless of the make, pH meters are usually robust and should need little maintenance. 

Apply silicone to the outside top of the 1" ID pipe cap. Keep the silicone away from the electrode hole so that when the screw connector goes through this hole, it does not get silicone on its threads, which would compromise the electrical connection. Now, push the 10/24 screw electrode connector through the wire mesh (see illustration)... 

Insert the electrode connector screws from the inside, though a nickel washer, then the Monel screen,... 

A silicon carbide rod, held in place by two electrode connector clamps, is fitted into a Liebig condenser. The electrode clamps are sealed into Pyrex caps, which fit over the groimd-glass male joints of the condenser. 

Furthermore, the electrode should always be immersed carefully into the electrolyte solution. Otherwise, corrosion products of the electrode body or of electrode connectors are almost guaranteed to spoil the intended electrochemical experiment. Corrosion will preferably occur at loci of high current densities, which are typically produced when contacts to the electrode made by alligator clips are immersed into the electrolyte solution. This is also true for the case where entire solid samples need to be contacted in order to undertake electrochemical studies. Therefore, under no circumstances should the contact area be allowed to be wetted by the electrolyte solution. This problem can be circumvented by suitably covering the contact area in the case of an electrolyte solution with low surface tension, this process can be hard work and may even lead to the construction of a special cell design. 

See Figure 7.33 and Section 7.13. The electrode wire is a trivial but very important part of the electrode. There are many things to consider the best cable track, no wire drag on the electrode, and minimal weight of the electrode connector. Very flexible wire, perhaps shielded The best is to have no connector at the electrode side, a wire with prefabricated direct entry into the electrode. 

With an electrode connector, the left version in Figure 7.33 has the problem that to connect, pressure must be applied that can squeeze contact electrolyte out and make the skin contact area unstable. The connector in the middle can be fixed without any vertical... 

Fig. 2.8. Zirconium Chloride Plant. 1, feed hopper 2, star valve feeder 3, ball valve 4, silica brick 5, steel shell 6, insulating brick 7, clean out 8, water-cooled copper electrode connector 9, graphite electrode and nipple 16, chlorine inlet pipe 11, nickel cross-over pipe 12, primary condenser 13, condenser jacket 14, ba 3e 15, discharge valve 16, air heater 17, blower 18, cyclone-type aftercondenser 19, water scrubbing tower 20, caustic scrubbing tower 21, exit gas outlet to stack 22, caustic circulating pump 23, waste water inlet 24, caustic bleed line (Stephens, W. W. and Gilbert, H. L.

Presently platinum or silver wire is generally used to connect into glass electrodes. In some cases, the silver wire is chlorided to make a reversible-electrode connector. Reversible electrodes are discussed in Chapter 5. 

Electronic Applications. The PGMs have a number of important and diverse appHcations in the electronics industry (30). The most widely used are palladium and mthenium. Palladium or palladium—silver thick-film pastes are used in multilayer ceramic capacitors and conductor inks for hybrid integrated circuits (qv). In multilayer ceramic capacitors, the termination electrodes are silver or a silver-rich Pd—Ag alloy. The internal electrodes use a palladium-rich Pd—Ag alloy. Palladium salts are increasingly used to plate edge connectors and lead frames of semiconductors (qv), as a cost-effective alternative to gold. In 1994, 45% of total mthenium demand was for use in mthenium oxide resistor pastes (see Electrical connectors). 

Electrical Connections. Electric current is brought from the transformers by air-cooled copper busbars and close to the electrode by water-cooled bus tubes and flexible cables, connecting to water-cooled copper contact plates at the electrode. The plates are held against the electrode by hydraulic pressure. The connectors are as short and as balanced as possible to allow cancelling of magnetic fields associated with individual conductors. 

Figure 8.12 Two types of electrotransfer apparatus. At the left a tank transfer cell is shown in an exploded view. The cassette (1) holds the gel (2) and transfer membrane (3) between buffer-saturated filter paper pads (4). The cassette is inserted vertically into the buffer-filled tank (5) between positive and negative electrodes (not shown). A lid with connectors and leads for applying electrical power is not shown. On the right side of the figure is shown an exploded view of a semidry transfer unit. The gel (5) and membrane (6) are sandwiched between buffer-saturated stacks of filter paper (4) and placed between the cathode assembly (3) and anode plate (7). A safety lid (1) attaches to the base (9). Power is applied through cables (8).

Reference Electrodes By definition, the normal hydrogen electrode (N H E) is the reference for electrode potentials (see Sect. 2.3.2.1), but practically it is scarcely usable. A reference electrode (RE) has to provide a well-defined potential between the electrolyte and its electric connector, joined with the input of the measuring instrument. Usually, a metal and a slightly soluble salt of this metal is applied (secondary electrode) [76, 77]. The electrolyte in the RE is connected to the electrolyte in the electrochemical cell via a diaphragm, which has to separate both electrolytes, as far as possible without a potential difference (see below). 

Fill the transfer tank with lx transfer buffer so that the buffer completely covers the electrode panels but does not touch the electrical connectors. 

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