Density lead oxides

Paste Mixing. The active materials for both positive and negative plates are made from the identical base materials. Lead oxide, fibers, water, and a dilute solution of sulfuric acid are combined in an agitated batch mixer or reactor to form a pastelike mixture of lead sulfates, the normal, tribasic, and tetrabasic sulfates, plus PbO, water, and free lead. The positive and negative pastes differ only in additives to the base mixture. Organic expanders, barium sulfate [7727-43-7] BaSO carbon, and occasionally mineral oil are added to the negative paste. Red lead [1314-41 -6] or minium, Pb O, is sometimes added to the positive mix. The paste for both electrodes is characterized by cube weight or density, penetration, and raw plate density. 

Lead Oxides Leady litharge containing 25 to 30 percent free lead is required for storage-batteiy plates. It is processed on Raymond Imp mills. They have the ability to produce litharge that has a desired low density of 1.1 to 1.3 ff/cm (18 to 22 g/iu ). A 56-kW (75-hp) unit produces 860 kg/h (1900 Ib/h) of materialhaving this density. 

The uniformity of film thickness is dependent upon temperature and pressure. The nucleation rate rises with pressure, such that at pressures above atmospheric the high rate of nucleation can lead to comparatively uniform oxide films, while increase in temperature reduces the density of oxide nuclei, and results in non-uniformity. Subsequently, lateral growth of nuclei over the surface is faster than the rate of thickening until uniform coverage is attained, when the consolidated film grows as a continuous layer ... 

Once the thermal runaway had become established, the high temperature could allow a smelting reaction (reduction of lead oxides by carbon to metallic lead) to occur, and the low m.p. and high density (327°C, 10.6, respectively) would cause the molten lead to concentrate at the base of the reactor, decreasing the lead content and raising the manganese content of the bulk of the clinker residue, as was observed [2],... 

Compds containing waxy materials have been used in the role of simulating, principally density, in expl systems. Ammo containing the inert load are used for training purposes and engineering tests. In the early 1930 s inert fillers used were lead oxide/paraffin, barium carbonate/ paraffin and barium carbonate/paraffin/lead oxide. The specific desired density was obtained by varying the proportions of the constituents... 

In this chapter we discnssed the reaction mechanisms of the most important electrochemical reactions involved in low temperature fuel cells. Apart from the hydrogen oxidation reaction, which is relatively easy, and does not lead to a large overpotential even at high current densities, the oxidation of low weight alcohols... 

The catalytic activity of bismuth-lead molybdate catalysts is related to the defect site densities. Olefin oxidations take place most rapidly when ( ) = 0.06. Acrylonitrile is formed by the ammoxidation of propene in about 75% yield over these mixed oxides when <(> is between 0.04 and 0.08.38... 

Lead oxide (Table 7) and the lead dimer (Table 8) are reasonably well studied by both relativistic density functional and ab initio methods. 

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