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| Bombs
And Explosives |
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need for studying bombs and explosives by forensic personnel mainly
relates to mass murder cases, where bombs would obviously be the ideal
weapon .Such bomb cases also have their own special methods to help
deduce different forms of evidence. |
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Choose one of the following topics to read more:
--> Bombs
--> What
are bombs?
--> Bomb
deposits
--> Fragments
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| Bombs |
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| Today, making a bomb is
a very simple exercise, with recipes readily available on the internet
and the materials easily accessible. The make-up of a bomb is very
simple and easily fashioned. A timer or remote control device is used
to start the primary charge, or spark, which then ignites the gas
inside the bomb, triggering a much larger, high powered blast which
causes the damage. |
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| What
is a Bomb? |
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| The are many bomb types
available, some very basic ones that yield little power and some which
can cause mass destruction. But what's important is to know that an
explosion from a bomb occurs as a result of an endothermic
chemical reaction, which is one that releases vast amounts of heat
energy and takes place very quickly, thus releasing an explosion.
The chemical reactants the bomb maker decides to use reflects on the
power of the bomb, since some chemical reactions release more energy
than others.
Noble gases and alkali
metals are among some of the most reactive elements in the
periodic table and their compounds are likely bomb materials for eg.
In a basic soda bomb, the use of sodium bicarbonate is the use of
a sodium compound, subsequently an alkali metal. |
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| Bomb
Deposits |
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When a bomb explodes, a lot of it is thrown far away from the scene.
Investigators search for any possible fragments of the bomb by agents
that react by changing colour when it comes in contact with fuel.
Fragments that carry traces of unburned fuel are taken back to the
laboratory, where they are studied under microscopes. The shapes
of the fuel particles are identified and are then washed in water
and a colourless and inflammable liquid called acetone.
The purpose of this process is to turn the particles into a liquid
solution for further testing.
The solution is then screened and analysed using
mass
spectrometry, which involves an instrument that breaks
up ions. These ions are attracted into a magnetic
field and when their charges are measured in contrast
to the mass of the ions, it identifies the chemical composition
of the solution.
Another method used is thin-layer
chromatography, which involves the liquid sample being
pushed in an upward direction by a specially coated plate, using
an organic solvent that soaks upwards from the base. The different
components in the liquid sample move up at different speeds and
separate onto a plate, which then allows the solution to be identified.
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| Fragments |
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| Even though when a bomb
explodes, it is reduced tiny fragments, these fragments can still
lead investigators to the bomb's creator. Occasionally, the fragments
of the bomb may carry fingerprints, but in most situations, a piece
of a bomb simply leads to determining where the bomb was manufactured.
Explosives units around the world usually retain a large collection
of frequently used bomb parts, batteries, timers, remote control devices
and fuel components, which makes it possible for investigators find
similarities between certain blasts. |
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