Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Electro-conductive additives

Electro-conductivity of molten salts is a kinetic property that depends on the nature of the mobile ions and ionic interactions. The interaction that leads to the formation of complex ions has a varying influence on the electroconductivity of the melts, depending on the nature of the initial components. When the initial components are purely ionic, forming of complexes leads to a decrease in conductivity, whereas associated initial compounds result in an increase in conductivity compared to the behavior of an ideal system. Since electro-conductivity is never an additive property, the calculation of the conductivity for an ideal system is performed using the well-known equation proposed by Markov and Shumina (Markov s Equation) [315]. [Pg.149]

Some theoretical prerequisites for application of modified and expanded graphites, Si- and Sn-based composites and alloys, electroconducting polymers as active materials, catalysts and electro-conductive additives for lithium - ion batteries, metal-air batteries and electrochemical capacitors are considered. The models and the main concepts of battery-related use for such materials are proposed. [Pg.311]

Electro-conductive rubber material Because of its great strength and much lower price than such expensive metals as silver and palladium, nano copper or copper-silver double metal powder can be used in the electronics industry to take the place of those expensive metals for the preparation of electro-conductive rubbers [191], electro-conductive slurry, and electrode materials etc. in addition, the copper-silver double metal powder has the characteristic of antibiosis. For such use nano copper or copper-silver powder should be needle-like crystalline the nano copper powders of sphere-like crystalline has very low electro-conductivity. [Pg.285]

The Thomson effect is related to the release of extra heat in a conductor (in addition to the well known Joule heat released due to the finite value of the electric conductivity) owing to the combined action of heat and electro conduction. In physical chemistry, classical examples of conjugate processes in nonuniform systems are thermomechanical and mechanocaloric effects. [Pg.80]

With regard to substrate-selective sensors with pre-organized cavities, impressive advances have been made in molecular imprinting [55-57]. The discovery of MIP-membrane electro conductivity was an interesting issue, which actually led to the appearance of the earliest MIP sensors [58,59]. It was shown that the membrane electroconductivity could be a function of the interaction between MIP-membrane and ligand (i.e., imprint species) (Fig. 5). An increase in the ligand concentration would result in an enhancement of membrane conductivity. With the same level of concentration, a maximal electro conductivity with the imprint species could be achieved. In addition, it has also been confirmed that polymers imprinted with amino acids, nucleosides, atrazines, sialic acids, or cholesterols can show similar features if coupled with the appropriate transducer [60-64], In particular, molecular imprinting is presently probably the only choice when no suit-... [Pg.198]

Similar to the interaction of individual polyacids and polybases with surfactants, cationic detergents form cooperative complexes with acidic groups of polyampholytes, and anionic ones with their basic groups [75-78]. The addition of detergents leads to considerable variation in pH, electro conductivity, turbid-... [Pg.152]

Positive plates need much more time to form than negatives. The reason for this is the dielectric behaviour of the cured positive paste. Oxidation of the bivalent lead compounds in the paste and formation of the Pb02 positive active mass passes through a number of chemical reactions, some of which proceed at a low rate, which retards the technological process of formation of the positive plate. In an attempt to accelerate the formation process, additives to the positive paste have been looked for, which are characterised by electro-conductive properties and stability in sulfuric acid. These additives create an electro-conductive network in the paste and the process of oxidation proceeds simultaneously within a large paste volume, thus accelerating plate formation. [Pg.350]

Carbon materials have long been incorporated into the electrodes of energy-storage devices as electro-conductive additives supports for active materials electron transfer catalysts intercalation hosts substrates for... [Pg.420]

In this section, additives for cathodes are reported by categorizing them into (1) sulfur-containing compounds with active site poisoning function [105-107] and (2) aromatic compounds forming an electro-conducting membrane (ECM) [2,109,110]. [Pg.183]

In classic electro-thermal atomizer the process of formation of the analytical signal is combination of two processes the analyte supply (in the process of evaporation) and the analyte removal (by diffusion of the analyte from the atomizer). In double stage atomizer a very significant role plays the process of conductive transfer of the analyte form the evaporator to the atomizer itself and this makes the main and a principle difference of these devices. Additionally to the named difference arises the problem with optimization of the double stage atomizer as the amount of design pai ameters and possible combination of operation pai ameters significantly increases. [Pg.84]

The stereochemistry of dienes has been found to have a pronounced effect in the concerted cyclo-additions with benzyne 64>65h A concerted disrotatory cyclo-addition of tetrafluorobenzyne, leading for example with trans- (3-methylstyrene to (63, R = Me), is likely and in accord with the conservation of orbital symmetry 68>. However while the electro-cyclic rearrangement of (63, R = H) to (65, R = H) is not allowed, base catalysed prototropic rearrangement is possible. A carbanion (64, R = H) cannot have more than a transient existence in the reaction of tetrafluorobenzyne with styrene because no deuterium incorporation in (65) was detected when either the reaction mixture was quenched with deuterium oxide or when the reaction was conducted in the presence of a ten molar excess of deuteriopentafluorobenzene. [Pg.56]

Reversed-phase separations currently dominate in CEC. As a result, the vast majority of the mobile phases are mixtures of water and an organic solvent, typically acetonitrile or methanol. In addition to the modulation of the retention, the mobile phase in CEC also conducts electricity and must contain mobile ions. This is achieved by using aqueous mixtures of salts instead of pure water. The discussion in Sect. 2 of this chapter indicated that the electro osmotic flow is created by ionized functionalities. The extent of ionization of these functionalities that directly affects the flow rate depends on the pH value of the mobile phase. Therefore, the mobile phase must be buffered to a pH that is desired to achieve the optimal flow velocity. Obviously there are at least three parameters of the mobile phase that have to be controlled (i) percentage of the organic solvent, (ii) the ionic strength of the aqueous component, and (iii) its pH value. [Pg.37]

Electro- magnetic Liquids only 1.5 (See Volume 1, Section 6.3.9) Additives in pharmaceuticals, paint, pulp and paper, water treatment using chlorine Good chemical resistance. Hygenic and intrinsically safe. Wide range. Requires some conductivity... [Pg.449]


See other pages where Electro-conductive additives is mentioned: [Pg.288]    [Pg.285]    [Pg.569]    [Pg.925]    [Pg.336]    [Pg.140]    [Pg.193]    [Pg.206]    [Pg.351]    [Pg.351]    [Pg.351]    [Pg.354]    [Pg.597]    [Pg.181]    [Pg.222]    [Pg.12]    [Pg.371]    [Pg.113]    [Pg.1317]    [Pg.1925]    [Pg.385]    [Pg.509]    [Pg.59]    [Pg.375]    [Pg.56]    [Pg.49]    [Pg.391]    [Pg.740]    [Pg.1105]    [Pg.385]    [Pg.509]    [Pg.469]   
See also in sourсe #XX -- [ Pg.351 ]




SEARCH



Conductive additive

© 2024 chempedia.info