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The oldest known pills were made of the zinc carbonates hydrozincite and smithsonite. The pills were used for sore eyes and were found aboard the Roman ship Relitto del Pozzino, wrecked in 140 BC. [78] [79] The Berne zinc tablet is a votive plaque dating to Roman Gaul made of an alloy that is mostly zinc. [80]
Zinc fingers help read DNA sequences.. Zinc is an essential trace element for humans [1] [2] [3] and other animals, [4] for plants [5] and for microorganisms. [6] Zinc is required for the function of over 300 enzymes and 1000 transcription factors, [3] and is stored and transferred in metallothioneins.
Zinc is mined as a mineral resource used by humans at a rate of 9800 Gg/yr [1] for use in metal alloys including brass and nickel silver, for galvanizing steel, and in zinc compounds such as zinc oxide. Half of zinc waste from industrial use is from tailings and slag; the rest comes from the oxidation of zinc metals and landfill waste ...
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
In prokaryotes, zinc can function as an antimicrobial, zinc oxide nano-particles can function as an antibacterial or antibiotic. Zinc homeostasis is highly controlled to allow for its benefits without risk of death via its high toxicity. [8] Because of zinc's antibiotic nature, it is often used in many drugs against bacterial infections in humans.
Zinc sulfide (or zinc sulphide) is an inorganic compound with the chemical formula of ZnS. This is the main form of zinc found in nature, where it mainly occurs as the mineral sphalerite . Although this mineral is usually black because of various impurities, the pure material is white, and it is widely used as a pigment.
Naturally occurring zinc (30 Zn) is composed of the 5 stable isotopes 64 Zn, 66 Zn, 67 Zn, 68 Zn, and 70 Zn with 64 Zn being the most abundant (48.6% natural abundance).Twenty-eight radioisotopes have been characterised with the most stable being 65 Zn with a half-life of 244.26 days, and then 72 Zn with a half-life of 46.5 hours.
Zinc oxide is an inorganic compound with the formula Zn O.It is a white powder which is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, [12] paints, sunscreens, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, semi conductors ...