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Lead has the highest atomic number of any stable element and three of its isotopes are endpoints of major nuclear decay chains of heavier elements. Lead is a relatively unreactive post-transition metal. Its weak metallic character is illustrated by its amphoteric nature; lead and lead oxides react with acids and bases, and it tends to form ...
Lead interferes with metabolism of bones and teeth [188] and alters the permeability of blood vessels and collagen synthesis. [5] Lead may also be harmful to the developing immune system, causing production of excessive inflammatory proteins; this mechanism may mean that lead exposure is a risk factor for asthma in children. [188]
Lead is the most prevalent heavy metal contaminant. [57] Levels in the aquatic environments of industrialised societies have been estimated to be two to three times those of pre-industrial levels. [58] As a component of tetraethyl lead, (CH 3 CH 2) 4 Pb, it was used extensively in gasoline from the 1930s until the 1970s. [59]
Lead (82 Pb) has four observationally stable isotopes: 204 Pb, 206 Pb, 207 Pb, 208 Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide.The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series ...
The FDA recommends a maximum of 0.1 parts per million (ppm) of lead in candy, but many imported types exceed this limit. The lead usually comes from things like lead-based ink used on the ...
The lead–acid battery is a type of rechargeable battery first invented in 1859 by French physicist ... and thereby improves handling and pasting characteristics. It ...
IUoU is a DIN-designation [1] (DIN 41773) for a lead-acid battery charging procedure that is also known as 3-stage charging, 3-phase charging, or 3-step charging. It consists of three phases (or stages), to be executed by a battery charger .
Lead white paint dries relatively quickly to form a strong, flexible paint film. Lead-based white is one of the oldest manufactured pigments. It was the only white pigment available to artists in appreciable quantities until the twentieth century, when zinc white and titanium white became available. [44]