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CSI Analysis Evidence

Decent Essays

Analysis of Paper Documents
The scientist from CSI explains that when the pen enters in contact with the paper, one part of the ink remains on the surface but the lower layers of the paper absorbs the other part. It allows scientists to recover what was written in a paper that was in contact with water, as example used in the episode. To analyse evidence like this it is necessary to do a procedure with Multi-spectral imaging system (United Nations Office on Drugs and Crime 2010), using equipment as a light source, a stereomicroscope, a magnifier, an UV light source and a VSC2000 Video Spectral Comparator (Virginia Department of Forensic Science 2012). Firstly, it is necessary to conduct a visual exam using natural or artificial lighting. Then, …show more content…

The sample can be collected with a tape, swab or even scraping and cutting objects (Williamson 2012). Then, a Polymerase Chain Reaction (PCR) is done to increase the number of genes (Houck & Houck 2008). Next, the sample is mixed with fluorescent compounds, which attach themselves to 13 specific locations in the DNA, finally giving a specific genetic profile of the person (Houck & Houck …show more content…

The material was suggested as motor oil. Then, the team analysed the motor oil of each motorcycle. They also explained that each motorcycle would generate specific motor oil because besides the components of each oil varies from branch to branch, each oil will contain particle of iron zinc from the motor of the motorcycle itself. After the collection, the team analysed the samples in an Inductively Coupled Plasma Mass Spectrometry.
In ICP, the sample goes through a peristaltic pump into a nebulizer where it will be broken into an aerosol of small droplets by a fast stream of argon gas. Then, it will pass through a spray chamber, eliminating larger droplets, going to the quartz plasma torch. The plasma will ionize and excite the atoms, which will emit light from their ions, which in turn, will passes through the monochromators, separating the light into many wavelengths. The light then will reach the charge-couped device (CCD) detector (Wolf

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