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Conductivity carbons

Power Gables. The materials mostly used to produce power cables are ethylene copolymers loaded with conductive carbon black for ... [Pg.328]

Antistats such as polyoxyethylenes (151,152) and A/-alkyl polycarbonamide (153) are added to nylon to reduce static charge and improve moisture transport and soil release in fabrics. These additives also alter the luster of fiber spun from bright polymer. Static reduction in carpets is achieved primarily by the use of fibers modified with conductive carbon black (see Antistatic agents Carbon, carbon black). [Pg.257]

Bicomponent technology has been used to introduce functional and novelty effects other than stretch to nylon fibers. For instance, antistatic yams are made by spinning a conductive carbon-black polymer dispersion as a core with a sheath of nylon (188) and as a side-by-side configuration (189). At 0.1—1.0% implants, these conductive filaments give durable static resistance to nylon carpets without interfering with dye coloration. Conductive materials such as carbon black or metals as a sheath around a core of nylon interfere with color, especially light shades. [Pg.258]

Vulcani2ed mbber is an insulator (volume resistivity is 10 Q-cm), and the static generated by mbber tires created serious problems in vehicles until the introduction of electrically conductive carbon black as a reinforcing pigment. An excellent correlation was found between the potential generated and the resistivity of the tires (127,128) (see Rubber natural). [Pg.296]

N. Prost, Conductive Bacbber Compounds—Compounding with Extra-Conductive Carbon Black, Phillips Petroleum Chemicals Bulletin, June 1985. [Pg.556]

Most sulphones are known to react with chemical reducing reagents like dissolved metals or amalgams. However, electron transfers may be produced also directly from metallic or conducting carbon cathodes maintained at a certain potential depending on the desired reducing power. We will discuss the reactivity of sulphones towards electrons issued from cathodes, especially in the light of recent results. [Pg.1002]

Similarly, Pd, Ag, and Pd-Ag nanoclusters on alumina have been prepared by the polyol method [230]. Dend-rimer encapsulated metal nanoclusters can be obtained by the thermal degradation of the organic dendrimers [368]. If salts of different metals are reduced one after the other in the presence of a support, core-shell type metallic particles are produced. In this case the presence of the support is vital for the success of the preparation. For example, the stepwise reduction of Cu and Pt salts in the presence of a conductive carbon support (Vulcan XC 72) generates copper nanoparticles (6-8 nm) that are coated with smaller particles of Pt (1-2 nm). This system has been found to be a powerful electrocatalyst which exhibits improved CO tolerance combined with high electrocatalytic efficiency. For details see Section 3.7 [53,369]. [Pg.36]

The catalyst layer is the most expensive part of this fuel cell. It is made from a mixture of platinum, carbon powder, and PEM powder, bonded to a conductive carbon fiber cloth. We obtained ours from E-Tek Inc. The cost for an order of their ELAT catalyst cloth sheet includes a setup charge. So get together with others for a larger order if you want to keep costs down. We paid 360 for a piece of ELAT 15.2 centimeters by 15.2 centimeters [6 inches by 6 inches] including the 150 setup charge. This piece provides enough for about twelve disks. Each fuel cell requires two disks of ELAT and one larger disk of PEM to make the sandwich, so you can make six cells from this size... [Pg.2]

Carbon. The electronically conductive carbons are derived from the hexagonal crystalline modification—graphite. [Pg.324]

Figure 2 shows the SEM image of the flake at a magnification of 350 x, as it was mounted on the conductive carbon tape. If there is a polymeric film covering the sample, the SEM will only show the surface topography of the film, not the structure residing below the polymeric film. EDS was conducted on two areas on the sample as indicated in Figure 2. The EDS analysis was conducted in square spot mode, approximately 1 pm by 1 pm in size. The elemental results are shown in Table 2. Based on these data sets it is apparent that the Type A defect is an iron-rich particle. Based on the lack of chromium or nickel the Type A defect is a particle of steel, not stainless steel. Figure 2 shows the SEM image of the flake at a magnification of 350 x, as it was mounted on the conductive carbon tape. If there is a polymeric film covering the sample, the SEM will only show the surface topography of the film, not the structure residing below the polymeric film. EDS was conducted on two areas on the sample as indicated in Figure 2. The EDS analysis was conducted in square spot mode, approximately 1 pm by 1 pm in size. The elemental results are shown in Table 2. Based on these data sets it is apparent that the Type A defect is an iron-rich particle. Based on the lack of chromium or nickel the Type A defect is a particle of steel, not stainless steel.
A classic case is an EC of a faradic type in which an electrode is comprised of Ni(OH)2, MnOOH, etc. active materials. Since in these chemistries the conductivity depends on electrode state-of-charge charge level, they require presence of additional stable conductive skeletons in their structure. Noteworthy mentioning that besides traditional forms of carbon or other conductors that may form such a skeleton, the latest progressive investigations demonstrate the possibility of application of different nanostructured forms of carbon, such as single-wall and multi-wall carbon nanotubes [4, 5], Yet, for the industrial application, highly conductive carbon powders, fibers and metal powders dominate at present. [Pg.45]

Summarizing the above, it may be stated that activated carbons and pseudocapacitive materials in EC electrode structure are responsible for the energy storage parameters (specific energy), while non-active highly conductive carbon additives are responsible for the electrode internal resistance (EC specific power). [Pg.45]

Before measuring conductivity, carbon materials and their mixtures were dried to residual moisture content of less than 5wt%. A sample of the investigated material was put into a measuring cell, representing a dielectric cylinder closed at both ends by the measuring electrodes. [Pg.45]

First of all let us consider the morphological structure of an agglomerate electrode [6] by way of example of the model shown in Figure 1. This schematic represents a multiphase system with no fixed connection between its components. As a rule, the active mass of an electrode is a mixture of Nickel hydroxide (oxyhydroxide) with conductive carbon or a metal, which are well dispersed mechanically in the matrix. [Pg.51]

Figure 3 shows changes of the ESR and capacity during cycling. High stability of conductive carbon, represented by Boron-doped refined graphite (2939APH RG) in this critical test conditions was observed. [Pg.52]

Carbon-Zinc Sealant, cathode conductive carbon black matrix... [Pg.176]

In the paper from V. Matveyev of the Ukrainian State University of Chemical Engineering, an examination of the role of conductive carbon additives in a composite porous electrode is conducted. A model for calculation of the local electrochemical characteristics of an electrode is presented. A comparison on the polarization of the electrode as a function of the redox state of the electroactive species is emphasized in the model. The electrochemical reaction of chloranil (tetrachlorobenzoquinone) was measured and results compare favorably to calculations derived from the model. [Pg.451]

MODELING OF ELECTROCHEMICAL PROCESSES IN THE ELECTRODES BASED ON SOLID ACTIVE REAGENTS AND CONDUCTIVE CARBON ADDITIVES... [Pg.461]

Sterling NS is a fairly conductive carbon black and dispersions of... [Pg.339]

For a fast catalytic reaction, free access of gas, electrons, protons and water is needed. This leads to a best compromise of the volume fractions of protonconducting polymer, electron-conducting carbon, active sites and void space. [Pg.320]

It has been pointed out however that further innovative steps are needed before single nano-tubes devices with adequate reproducibility can be made. A paper by Zhang et al. (2006) indicates parallel research lines intended to develop the various complementary aspects of nano-sciences and their applications. They observed that metallic and semi-conducting carbon nano-tubes generally coexist in as grown... [Pg.599]

Zhou, Y., et al., Electrostatic self-assembly of graphene-silver multilayer films and their transmittance and electronic conductivity. Carbon, 2012. 50(12) p. 4343-4350. [Pg.167]

The ink , when screen-printing, is a slurry of conductive carbon particles (sometimes in a solution of conductive resin) that flows smoothly when wet and sets quickly without losing definition and shape. Alternatively, conductive silver paint (as above) will perform the same function. [Pg.287]


See other pages where Conductivity carbons is mentioned: [Pg.243]    [Pg.329]    [Pg.295]    [Pg.558]    [Pg.552]    [Pg.552]    [Pg.34]    [Pg.135]    [Pg.363]    [Pg.356]    [Pg.310]    [Pg.17]    [Pg.657]    [Pg.453]    [Pg.32]    [Pg.88]    [Pg.341]    [Pg.18]    [Pg.517]    [Pg.296]    [Pg.85]    [Pg.210]    [Pg.211]    [Pg.114]    [Pg.295]   
See also in sourсe #XX -- [ Pg.231 ]




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