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A bronze is an alloy of copper and other metals, most often tin, but also aluminium and silicon. Aluminium bronzes are alloys of copper and aluminium. The content of aluminium ranges mostly between 5% and 11%. Iron, nickel, manganese and silicon are sometimes added.
Peak copper is the point in time at which the maximum global copper production rate is reached. Since copper is a finite resource, at some point in the future new production from mining will diminish, and at some earlier time production will reach a maximum. When this will occur is a matter of dispute.
The copper IUD is the most effective form of emergency contraception. It is more effective than the hormonal EC pills currently available. [18] The pregnancy rate among those using the copper IUD for EC is 0.09%. It can be used for EC up to five days after the act of unprotected sex and does not decrease in effectiveness during the five days. [19]
Beryllium copper (BeCu), also known as copper beryllium (CuBe), beryllium bronze, and spring copper, is a copper alloy with 0.5–3% beryllium. [1] Copper beryllium alloys are often used because of their high strength and good conductivity of both heat and electricity. [2] It is used for its ductility, weldability in metalworking, and machining ...
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [ 1 ] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals.
Isotopes of copper. Copper (29 Cu) has two stable isotopes, 63 Cu and 65 Cu, along with 28 radioisotopes. The most stable radioisotope is 67 Cu with a half-life of 61.83 hours. Most of the others have half-lives under a minute. Unstable copper isotopes with atomic masses below 63 tend to undergo β + decay, while isotopes with atomic masses ...
The Old Copper complex or Old Copper culture is an archaeological culture from the Archaic period of North America's Great Lakes region. Artifacts from some of these sites have been dated from 6500 to 1580 BCE. [1][2][page needed] It is characterized by widespread copper artifacts, including tools and weapons, as well as ornamental objects.
Copper. face-centered cubic (fcc) (cF4) Copper is a chemical element; it has symbol Cu (from Latin cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity ...