Graded electrodes

Property Regular-grade electrodes Premium-grade electrodes Premium-grade connecting pins... 

Fabrication of TICs with graded electrodes that have a conversion efficiency above 15%. 

For the above reasons, most efforts in the design and production of pH sensors have focused on the development of high-precision sensors for industrial process streams owing to the diverse and often difficult conditions that are experienced in these media. These pH sensors are designed to have long-term stability and extended life, based on the use of industrial-grade electrodes with silver/silver chloride reference electrodes incorporated into gel-polymer electrolytes. Some of the industrial-grade pH sensors use modified gel-solid electrolyte, which is free of silver chloride and, hence, can be used in presence of sulfides. 

Caldwell CW, Parker RC, Diehl H (1944) Apparatus for automatic control of electrodeposition with graded electrode potential. Ind Eng Chem 16 532-535... 

Dissociation of the second proton is insignificant. The pH of its aqueous solutions can be measured reproducibly with a glass electrode, but a correction dependent on the concentration must be added to obtain the tme pH value. Correction values for the most common commercial solutions are Hsted in Table 3. The apparent pH of commercial product solutions can be affected by the type and amount of stabilizers added, and many times the pH is purposely adjusted to a grade specification range. 

Pitch. The principal outlet for coal-tar pitch is as the binder for the electrodes used in aluminum smelting. These are of two types. Older plants employ Sn derberg furnaces, which incorporate paste electrodes consisting of a mixture of about 70% graded petroleum coke or pitch coke and 30% of a medium-hard coke-oven pitch. This paste is added periodically to the top of the monolithic electrode as it is consumed. The more modem smelters employ prebaked electrodes requiring less binder, about 18%. 

Sintered Cells. Tlie fabrication of sintered electrode batteries can be divided into fwe principal operations preparation of sintering-grade nickel powder preparation of the sintered nickel plaque impregnation of the plaque with actwe material assembly of the impregnated plaques (often called plates) into electrode groups and into cells and assembly of cells into batteries. 

Property Aluminum anode-grade coke Graphite electrode-grade needle coke... 

Table 2. Typical Room Temperature Properties of Regular- and Premium-Grade Graphite Electrodes and Connecting Pins...

A variety of products are made in submerged-arc furnaces. Among them are various alloys and compounds. Each uses a particular type or grade of carbon electrode to hold production costs at the lowest possible level. Graphite electrodes could be and are used in some submerged-arc furnaces. Such a choice is the result of special conditions that warrant use of the more expensive graphite in Heu of carbon. 

Several grades of carbon electrodes are available. The characteristics of each result from the raw materials and processes used ia manufacturiag. The generic descriptions and primary constituents are as follows ... 

The physical properties of carbon electrodes are deterrnined by the raw materials and processes used in their manufacturer. There are no universal grade designations and the pubHshed properties are quite broad. Table 3 shows ranges for some of the common commercially available grades. 

Table 3. Ranges of Physical Properties of Typical Carbon Electrode Grades...

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