| Term | Definition |
|---|
| Natural Fibers | Come from animals or plants, Animal fibers are most commonly found at crime scene, Animal fiber examination is the same as animal hair examination, |
| Cotton | comes from the cotton plat, the principal fiber of clothing in the world; fiber is hollow an looks like a twisted under a microscope |
| Wool | comes from the fur of animals like sheep, goats, mink, alpacas and llamas (Mohair – from the Angora goat; Angora wool – from the Angora rabbit; Cashmere – from the Kashmir goat) |
| Silk | comes from silkworm cocoons; for its size it is stronger than steel |
| Linen | is a vegetable fiber that is 2 to 3 times stronger than cotton; comes from stalk fibers of the flax point |
| Hemp | is a vegetable fiber taken from the stem of the Cannabis plant; it is very strong and can be used to make rope or woven into a fabric |
| Regenerated Fibers | fibers manufactured from natural raw materials |
| Synthetic | fibers produced in a lab from other materials |
| Acetate and Rayon | formed from regenerated cellulose obtained by dissolving cotton in various solvents |
| Nylon | the 1st synthetic fiber, discovered in 1930; can be stretched several times its length |
| Kevlar (aramid) | is a synthetic fiber sold by Dupont, It has great strength and great resistance to stretching, When woven properly it can be used as a bullet proof garment (not often marketed as bulletproof) some bullets can penetrate various vests, Different thicknesses of body armor can withstand different types of ammunition |
| Examinations of Fibers | Microscope comparison for color and diameter, shape, surface striations |
| Parts of hair | shaft, root |
| Layers of shaft | cuticle, medulla, cortex |
| cuticle | outside covering of hair, formed by overlapping scales |
| Cortex | located in the protective layer of the cuticle, composed of spindle shaped corticle cells, important aspect of comparison |
| Medulla | collection of cells running through the center of hair |
| Medullary Index | measures the diameter of the medulla relative to the diameter of the hair shaft (humans less than 1/3, others more than 1/3) |
| Humans | either haver no medulla or fragmented medulla (monogoloids have continuous) |
| Animals | either have continuous or interrupted |
| Cats | medullae have a string of pearls like appearance |
| Deer | medullae are like spherical shaped cells |
| Anagen Phase | May last up to 6 years, Root is attached to follicle, Root-bulb has a flame shaped appearance, Follicular tag may be found |
| Catagen Phase | Hair continues to grow, but at a decreasing rate, Lasts 2-3 weeks, Roots appear elongated, Root bulb shrinks in size and is being pushed out of hair follicle |
| Telogen Phase | This phase begins when hair growth ends, Root appears club shaped, Lasts 2 – 6 moths, Hair is pushed out of follicle causing hair to shed |
| Binder | support for pigments and additives |
| Pigments | color and opacity |
| Electrocoat primer | Color ranges from black to gray |
| Primer surface | Highly pigmented |
| Basecoat | Provides vehicle with its color |
| Clearcoat | Not pigmented |
| Microscope | locates and compares paint to specimens |
| Stereoscope | Used to compare color, surface texture, and color of layer sequence of paint |
| Prolysis Gas Chromatography | shows chemical make-up of binder |
| Infrared Spectrophotometry | aides in determing binder composition |
Combine with other sets
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