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Germanium | |||
The alloy silicon germanide[?] (SiGe) is rapidly becoming an important semiconductor material, for use in high speed integrated circuits. Circuits utilising the properties of Si-SiGe junctions can be much faster than those using silicon alone.
Other uses:
Certain compounds of germanium have low toxicity to mammals, but have toxic effects against certain bacteria. This property makes these compounds useful as chemotherapeutic agents.
| Property | Ekasilicon | Germanium |
|---|---|---|
| atomic mass | 72 | 72.59 |
| density (g/cm3) | 5.5 | 5.35 |
| melting point (°C) | high | 947 |
| color | gray | gray |
The development of the germanium transistor opened the door to countless applications of solid-state[?] electronics. From 1950 through the early 1970s, this area provided an increasing market for germanium, but then high purity silicon began replacing germanium in transistors, diodes, and rectifiers. Silicon has superior electrical properties, but requires much higher purity samples—a purity which could not be commercially achieved in the early days. Meanwhile, demand for germanium in fiber optics communication networks, infrared night vision[?] systems, and polymerization catalysts increased dramatically. These end uses represented 85% of worldwide germanium consumption for 2000.
Germanium is obtained commercially from zinc ore processing smelter dust and from the combustion by-products of certain coals. A large reserve of this element is therefore in coal sources.
This metaloid can be extracted from other metals by fractional distillation of its volatile tetrachloride. This technique permits the production of ultra-high purity germanium.
In 1997 the cost of germanium was about US$ 3 per gram. The yearend price for germanium in 2000 was $1,150 per kilogram.
Congreve, on his play called The Old bachelor.html">Bachelor.
Wit, like true gold, refined from all allay,
'Tis in all times and languages the same,
For, though the form and fashion don't remain,
Then let each studied scene be writ with art,
Each character be just, and nature seem:
For that's the soul, which all the mass must move,
But you, too bounteous, sow your wit so thick,
And while with clapping we are just to you,
What mayn't we then, great youth, of thee presage,
How wilt thou shine at thy meridian height,
When Dryden dying shall the world deceive,
Thou shalt succeed, the glory of the stage,
Written by the Lord Falkland.
Most authors on the stage at first appear
They judge, from the experience of the dame,
And who falls short of furnishing a course
With utmost rage from her embraces thrown,
Thus often, to his shame, a pert beginner
As for our youngster, I am apt to doubt him,
But he, more sanguine, trusts in one and twenty,
For though his bachelor be worn and cold,
And what alone can be achieved by neither,
The briskest of you all have felt alarms,
With broken sighs, in her old fumbler's arms:
Of any rivals, but young lusty fellows.
After his bragging, prove a washy knave,
And never more have leave to dip his.
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