Swedish chemist Jons Jakob Berzelius, was born on this date in 1779. He is credited with identifying the chemical element selenium. 10 things you might not know about selenium:
Its chemical symbol is Se and its atomic number is 34.
Berzellius discovered it in reddish deposits in the Lead chambers at his sulphuric acid plant at Gripsholm in Sweden. At first he thought it was a compound of arsenic, but later noticed that this stuff smelled like Horseradish when burned, and arsenic doesn’t. An element that does is tellurium, so Berzellius then assumed it was a compound of that. But wait. He couldn’t find any tellurium deposits in his mine, so he realised this must be something new.
Telluriam was named after the Earth, so given its similarity to this element, Berzellius decided to name it after the Moon. Selenium gets its name from the Greek word “selene”, which means “moon”. Selene was the Greek goddess of the moon.
Its melting point is 494 K (221 °C, 430 °F), and its boiling point is 958K(685 °C, 1265 °F).
Although large amounts of selenium are toxic, it is necessary for cellular function in animals in trace amounts.
Plants vary in terms of how much selenium they need, from requiring fairly large amounts to not needing it at all.
The US Recommended Dietary Allowance (RDA) of selenium for teenagers and adults is 55 μg/day. The richest dietary source is Brazil nuts. It’s also found in meat, nuts, cereals and Mushrooms.
The chief commercial uses for selenium today are glassmaking and pigments.
Historically it was used as an electrical conductor, although today it has largely been replaced by Silicon.
Alexander Graham Bell used selenium in his photophone developed in 1879.
The first in a new series! It has invading aliens, gladiator-style contests, rivalry and romance.
The six richest people in Britain decide to hold a contest to settle the question of which of them is most successful. It will be a gladiator style contest with each entrant fielding a team of ten super-powered combatants. Entrepreneur Llew Powell sets out to put together his team, which includes his former lover, an employee of his company with a fascinating hobby, two refugees from another dimension (a lonely giant and a drunken sailor), two sisters bound together by a promise, a diminutive doctor, a former Tibetan monk initiate and two androids with a history. As the team train together, alliances form, friendships and more develop, while others find the past is not easy to leave behind.
Meanwhile, a ruthless race of aliens has its eyes on the Earth. Already abducting and enslaving humans, they work towards the final invasion which would destroy life on Earth as we know it. Powell’s group, Combat Team Alpha, stumble upon one of the wormholes the aliens use to travel to Earth and witness for themselves the horrors in store if the aliens aren’t stopped. Barely escaping with their lives, they realise there are more important things to worry about than a fighting competition.
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