Graphite cloth

Diphenyl ditellurium was electrochemically reduced to benzenetellurolate in acetonitrile with sonication in anH-type cell. Tetrabutylammonium hexafluorophosphate served as the electrolyte. The cathode was a cylindrical graphite cloth and the anode a platinum grid. The cathodic solution was purged with argon. The potential had to be changed from — 1.20 to — 2.35 V during the reduction1-3. 

A convenient arrangement of a sacrificial selenium cathode is the tea bag method, in which a graphite cloth bag is filled with selenium pearls [143]. Other forms of sulfur or selenium electrodes have been described [144]. 

Para-Substituted anilines are oxidized in low to moderate yields to azobenzenes in basic solution (Table 5, number 4a). By elimination of one / ara-substituent (Cl or OMe) during the reaction, they can also couple to 4-substituted 4-aminodiphenyla-mines [76]. Carbon-carbon coupling can occur with 4-substituted arylamines as substrates. The / ara-substituent is eliminated and a / ara-benzidine is obtained (Table 5, number 6), ortho carbon-carbon coupling occurs (number 7), or a benzyl radical is formed, which subsequently couples (number 8). The ortho- and mera-substituted anilines yield at graphite cloth electrodes in 6iV H2SO4 substituted benzidines and 4-aminodiphenylamines. The latter products are converted by further oxidation and hydrolysis to 2-substituted / (7ra-benzoquinones, sometimes in substantial yields (e.g., 35%) [81],... 

A four-ply graphite cloth laminate based on polymer (e) was fabricated. Limiting oxygen index of this laminate was determined according to ASTM D2863-74 and was found to be 71%. Similar values for the graphite cloth laminates fabricated from 9,9-bis(p-maleimidophenyl)fluorene have been obtained earlier (2). 

Potassium 10-tungstodivanado (IV,V) phosphate was prepared by controlled potential reduction of a solution of the oxidized complex in an acetate buffer, pH 5. A graphite cloth cathode (Union Carbide Corp.)... 

In polymer electrolyte membrane fuel cells, like in many other kinds of fuel cells, gas-diffusion electrodes are used. They consist of a porous, hydrophobic gas-diffusion layer (GDL) and of a catalytically active layer. The diffusion layers (often called backing layers) usually consist of a mixture of carbon black and about 35% by mass of polytetrafluoroethylene (PTFE) applied to a conducting base (most often a thin graphitized cloth). The GDLs yield a uniform supply of reactant gas... 

HI Thompson Fiber Glass Co., Graphite cloth aids carburizing. Steel, 155, No. 14, 100, 1964. 

Most commonly, the battery will be configured with a stack of bipolar cells (10 -100 cells per stack) to give a useful output voltage and with parallel flows for the electrolytes to each of the cells in the stack. Hence, the electrodes will be bipolar with a solid core from carbon, graphite, or a carbon/polymer composite and the three-dimensional elements bonded or pressed onto either side of the solid core. The composites are a blend of a chemically stable polymer and a micron-scaled carbon powder, most commonly an activated carbon Radford et al. [127] have considered the influence of the source of the carbon and the chemical and thermal treatments on the properties of such activated carbons, especially the pore size and distribution [126]. Even though reticulated vitreous carbon has been used for the three-dimensional elements [117], the predominant materials are graphite cloths or felts with a thickness of up to 5 mm, and it is clear that such layers are essential to scale the current density and thereby achieve an acceptable power density. Details of electrode performance in the more developed flow batteries are not available but, for example, Skyllas-Kazacos et al. [124] have tabulated an overview of the development of the all vanadium redox flow battery that includes the electrode materials and the chemical and thermal treatments used to enhance activity and stability. 

The following polymeric materials have been used as ablative materials for specific applications phenolics, phenyl silanes, nitrile phenolics, nitrile rubber, silicones, epoxy polyamide, and novolac epoxies. Fillers and reinforcements are used in ablative formulations to improve performance and reduce thermal conductivity. Common ablative fillers are glass, siUca, and quartz cloth carbon and graphite cloth microbubbles (phenolic, silica, and glass) and asbestos fiber. 

Composite fabrication. Test laminates were prepared by coating graphite cloth (8-harness satin weave cloth) designed as a style 133 fabric with a DMF solution of bis-maleimide E and drying the prepregs in an air oven at 160°C-170°C for 15 min. The dried prepregs (4 or 9 plies) were stacked and pressed between aluminum plates covered with a tetrafluoroethylene film. The resulting laminate was then cured in a flat platen press at 232°C at a pressure... 

Table 6. Some Physical Properties of Graphite Cloth Laminates Based on Resin E...

Our results indicate that the high flame resistance for the graphite cloth laminates based on resin E is due to both the gas-phase and condensed-phase reactions of phosphorus. 

If electrode is carbon paper, graphite cloth, or other woven fabric, cut electrode subsample as needed. Try to cut a 1 cm x 1 cm square to keep surface area estimations simple. 

GRAPHITE, STRUCTURAL. Plates and shapes fabricated from laminated graphite cloth. Sp. gr. 1.2-1.8. Structural sections can be tailored to achieve required tensile and flexural properties in specific orientations. 

W. J. Gray, Neutron Irradiation Effects on Carbon and Graphite Cloths and Fibres, BNWL-2390, BatteUe, Pacific Northwest Laboratories, 1977. 

The commonest materials for the production of diaphragms are asbestos, ceramic, plastic materials, such as P.V.C., polypropylene and Terylene, graphite cloths and stainless steel. The two latter materials are conductors and, therefore, acquire a potential respective to the solution when placed in the cell. They may, if not properly designed and placed, function as extra electrodes in the cells. This should always be borne in mind when using conducting diaphragms. 

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