Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, greyish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Germanium has five naturally occurring isotopes ranging in atomic mass number from 70 to 76. It forms a large number of organometallic compounds, including tetraethylgermane and isobutylgermane. Because few minerals contain it in large concentration, germanium was discovered relatively late despite the fact that it is relatively abundant in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties based on its position on his periodic table and called the element ekasilicon. Nearly two decades later, in 1886, Clemens Winkler found it in the mineral argyrodite. Winkler found that experimental observations agreed with Mendeleev's predictions and named the element after his country, Germany. Germanium is an important semiconductor material used in transistors and various other electronic devices. Its major end uses are fiber-optic systems and infrared optics, but is also used for polymerization catalysts, in electronics and in solar electric applications. Germanium is mined primarily from sphalerite, though it is also recovered from silver, lead, and copper ores. Some germanium compounds, such as germanium chloride and germane, can irritate the eyes, skin, lungs, and throat.

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_______________________________ Today's selected anniversaries:

193:

Praetorian Guards assassinated Roman Emperor Pertinax and sold the throne in an auction to Didius Julianus. http://en.wikipedia.org/wiki/Pertinax

1795:

Partitions of Poland: The Duchy of Courland, a northern fief of the Polish–Lithuanian Commonwealth, ceased to exist and became part of the Russian Empire. http://en.wikipedia.org/wiki/Duchy_of_Courland_and_Semigallia

1802:

German astronomer Heinrich Wilhelm Matthäus Olbers discovered 2 Pallas, the second asteroid known to man. http://en.wikipedia.org/wiki/2_Pallas

1979:

A partial core meltdown of the Three Mile Island Nuclear Generating Station near Harrisburg, Pennsylvania, USA resulted in the release of an estimated 43,000 curies (1.59 PBq) of radioactive krypton to the environment. http://en.wikipedia.org/wiki/Three_Mile_Island_Nuclear_Generating_Station

2005:

The Sumatra earthquake hit Indonesia, killing approximately 1,300 people. http://en.wikipedia.org/wiki/2005_Sumatra_earthquake

_____________________________ Wiktionary's word of the day:

satay (n): An Indonesian dish made from small pieces of meat or fish grilled on a skewer and served with a spicy peanut sauce http://en.wiktionary.org/wiki/satay

___________________________ Wikiquote quote of the day:

Just as we cannot stop the movement of the heavens, revolving as they do with such speed, so we cannot restrain our thought. And then we send all the faculties of the soul after it, thinking we are lost, and have misused the time that we are spending in the presence of God. Yet the soul may perhaps be wholly united with Him in the Mansions very near His presence, while thought remains in the outskirts of the castle, suffering the assaults of a thousand wild and venomous creatures and from this suffering winning merit. So this must not upset us, and we must not abandon the struggle, as the devil tries to make us do. Most of these trials and times of unrest come from the fact that we do not understand ourselves. --Teresa of Avila http://en.wikiquote.org/wiki/Teresa_of_Avila