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Reb Blood Cells viewed by Scanning Electron Microscopy - SEM
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FORENSIC ANALYSIS (EXAMPLES)
FORENSIC ANALYSIS
CORROSION
Pieces of airplane wings from jet fighters, based on aircraft carriers, were brought to EMSL to compare the degree of corrosion following the application of various solvents used to desalt the airplanes. A small piece of the metal from each wing was embedded in epoxy and polished to a smooth finish. A detailed analysis with SEM and EDX was performed, and the level of corrosion was assessed in each sample. The results were used to pick the most effective desalting solvent.
EXPOLSIONS
An explosion and subsequent fire in a cargo tanker caused the ship to nearly sink along with ist cargo of iron pellets. EMSL was asked to determine if the cargo of iron pellets, known as Direct Reduced Iron (DRI), could have caused the accident. Analysis with the Scanning Electron Microscope (SEM) revealed aberrations in the protective coating applied to the pellets which alllowed access points for moisture to contact the sensitive inner surface of the DRI. Analysis was then pe
rformed to measure and identify gasses produced from the pellets when exposed to the conditions indicative of hold of a ship. It was determined that the DRI pellets would act as a catalyst to separate the hydrogen and oxygen in the highly humid air within the ship.
Furthermore, the cargo was sufficient to replace the air in the holds three times over with a combination of free hydrogen and oxygen. One spark is all it would take to ignite the hydrogen that would then be fed by oxygen resulting in and explosion capable of causing the accident that befell the cargo ship.
INDOOR AIR QUALITY
Respiratory problems were being experienced in a four-story post office building. EMSL requested air samples from the consultant hired to solve the problem for the client. SEM revealed the dominant presence of bacteria with concentrations diminishing with increased floor level. Conversations with the consultant revealed that pigeons socialized near the buildings AC system located outside the building at ground level. EMSL requested a pigeon feather and was able to match the bacteria on the pigeon feather with the airborne bacteria within the building.
FOOD PRODUCTS
A well-known soup manufacturer was having difficulty with a line of prepared soups. Their noodles would become too soft after cooking and consumers would not wish to purchase a product with mushy noodles. Cryogenic sectioning and staining of the noodles revealed poor bonding between the starches and proteins in the product when compared to other soups which consumers liked. The manufacturer was then able to alter the preparation process to yield a noodle which remained firm after cooking.
ACCIDENTS
An automobile was involved in an accident and the driver claimed that he could not stop. Upon inspection by a mechanic it was determined that the brake shoes may have been faulty. EMSL was asked to analyze the brakes. Extensive testing with Scanning Electron Microscopy revealed cracks and pores within the pads that were not within the tolerance limits for brake shoes. These defects caused the collapse of the brakes.
A motorcycle was involved in an automobile accident that occurred after dark. EMSL was asked to determine if the headlight of the motorcycle was on or off at the time of the accident. EMSL examined the filament of the smashed headlight and found, with Scanning Electron Microscopy (SEM) and X-Ray Microanalysis (EDX), the presence of microscopic glass fragments bound to the filament, thus proving that the filament was hot at the time of the accident.
An automobile was involved in an accident and the driver claimed that he could not stop. Upon inspection by a mechanic it was determined that the brake shoes may have been faulty. EMSL was asked to analyze the brakes. Extensive testing with Scanning Electron Microscopy revealed cracks and pores within the pads that were not within the tolerance limits for brake shoes. These defects caused the collapse of the brakes.
LEAD PAINT
EMSL was asked to determine if the paint covering the woodwork of an apartment building contained a specific type of lead pigment, which would point to a certain paint manufacturer. With SEM and EDX it was shown that the lead-based paint was present in only the three innermost (oldest) layers. By collecting paint only from these layers and performing X-Ray Diffraction Analysis (XRD) the presence of the specific lead pigment sought was established.
BIOLOGICAL
A hospital was experiencing an increased occurrence of infections in one of their intensive care units. EMSL was hired to determine the cause of the problem. Initial Air Quality analysis revealed an unusually high concentration of airborne mold spores. Additional testing narrowed the problem to an air conditioning unit that was collecting the water condensed by the cooling coils producing a natural incubator for mold growth. The problem was compounded by the fact that the contaminated water was next to the fresh air intake for that wing of the hospital.
QUALITY ASSURANCE
Many companies send the material used in the production of specialized products to EMSL for Quality Assurance. For example; a major manufacturer of brake pads submits the primary components used in the manufacture of their brakes for inspection to insure a quality product. They insist on an unbiased outside laboratory to perform the testing.
BIOLOGICAL
A hospital was experiencing an increased occurrence of infections in one of their intensive care units. EMSL was hired to determine the cause of the problem. Initial Air Quality analysis revealed an unusually high concentration of airborne mold spores. Additional testing narrowed the problem to an air conditioning unit that was collecting the water condensed by the cooling coils producing a natural incubator for mold growth. The problem was compounded by the fact that the contaminated water was next to the fresh air intake for that wing of the hospital.
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