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A condition called the zinc shakes or "zinc chills" can be induced by inhalation of zinc fumes while brazing or welding galvanized materials. [149] Zinc is a common ingredient of denture cream which may contain between 17 and 38 mg of zinc per gram. Disability and even deaths from excessive use of these products have been claimed.
The B 2 FH paper [1] was a landmark scientific paper on the origin of the chemical elements. The paper's title is Synthesis of the Elements in Stars, but it became known as B 2 FH from the initials of its authors: Margaret Burbidge, Geoffrey Burbidge, William A. Fowler, and Fred Hoyle.
The two discovered a new element in a molybdenum sample that was used in a cyclotron, the first element to be discovered by synthesis. It had been predicted by Mendeleev in 1871 as eka-manganese. [171] [172] [173] In 1952, Paul W. Merrill found its spectral lines in S-type red giants. [174]
The oldest known pills were made of the zinc carbonates hydrozincite (described 1853) and smithsonite (described 1832). Calamine is a historic name for an ore of zinc (hemimorphite (IMA1962 s.p.) and smithsonite). [6] De architectura (about 15 BC) of Marcus Vitruvius Pollio, Libri X, vol. VII, Caput 8.
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
Sphalerite is an important ore of zinc; around 95% of all primary zinc is extracted from sphalerite ore. [42] However, due to its variable trace element content, sphalerite is also an important source of several other metals such as cadmium, [ 43 ] gallium, [ 44 ] germanium, [ 45 ] and indium [ 46 ] which replace zinc.
The balangay was the first wooden marine vessel ever excavated in Southeast Asia. It is also known as the Butuan boat, as nine specimens of these boats, dating back to pre-Hispanic times (the earliest being in 320 CE), were discovered in 1976, Butuan, Mindanao. It is believed that the Austronesians migrated to the Philippine archipelago, riding ...
The other metals discovered before the Scientific Revolution largely fit the pattern, except for high-melting platinum: Bismuth melts at 272 °C (521 °F) [21] Zinc melts at 420 °C (787 °F), [21] but importantly boils at 907 °C (1665 °F), a temperature below the melting point of silver. Consequently, at the temperatures needed to reduce ...