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Morse Code
In 1825 the electromagnet was invented. By 1930 it had
been proved that a current could be sent down a mile of wire,
where it would activate an electromagnet and strike a bell.
This was the beginning of the electric telegraph. Samuel
Morse was the first man to develop this idea further. He
proved that he could use the magnet to move a marker, and produce
written codes that became known as Morse code.
The telegraph system sent the information as a series of electronic
signals. These signals could be either short (dots) or
long (dashes). Each letter of the alphabet is represented
by a combination of these signals, and the gaps between letters
and words are represented by pauses of set lengths.
The most well-known piece of Morse code is the signal for SOS.
S is represented by three short signals, O by three long, and another three short signals for the final S. |
VX and nerve gases
VX and Sarin are the best known nerve agents, and the most deadly.
They both work in a similar way, but VX is even more toxic
than Sarin. They work by preventing the nerve cells from communicating
with each other. Nerve cells use acetylcholine to send
messages to one another. They rely on an enzyme called
cholinesterase to allow them to pass acetylcholine to one another.
Sarin and VX work as cholinesterase inhibitors, thereby preventing
the communication process from taking place.
In most cases death is caused when this process paralyses the
muscles around the lungs, preventing the victim from breathing.
There is an antidote, but it has to be administered incredibly
fast. Just one drop of Sarin can kill in a couple of minutes,
so there is very little time to take action. |
Gas Masks
When a mask is used to protect against biological or
chemical attacks it must be a full face mask. It is easy
for bacteria to enter the body through the eyes so these must
be covered as well as the nose and mouth. Most gas masks
work by having a filter through which air must pass before it
can be breathed in. In the simplest filters this can just
work like a coffee filter, preventing larger particles in the
air, passing through. However, this method doesn’t
work against chemical threats. Since they tend to be carried
in mists or vapours they would pass easily through a filter
such as this.
The answer is an activated charcoal filter. Activated
charcoal has been treated with oxygen. This opens up millions
of pores between the carbon atoms, giving the charcoal a surface
area of 300-2,000m 2per gram. This enormously enlarged
surface area is the key to how this process works. As
the rogue chemicals pass through the carbon surface, they attach
to it and get trapped. Obviously, the more surface there
is the more places there are for the chemicals to get trapped.
But as with any gas mask, the mask must be airtight to be sure no impurities can creep through. |
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