The melanin composition when deposited to our hair strands usually gets dark and then thick. This is attributed to the melanin composition of the hair. You will notice that women with dark hair have denser hair which goes to say that they most likely have thick strands. Take a look at the women with dark hair and lighter hair. It plays an important role in determining hair thickness as it influences hair follicle development.ĭid you know that generally, those with dark hair have thicker strands than those with lighter colored hair. It is is a protein and encoded by the ADAR gene. Scientists think that many genes also contribute to hair thickness such as Ectodysplasin A receptor. Several genetic syndromes affect hair stability such as Monilethrix, Uncombable hair syndrome, etc. We are all born with a unique genetic composition and genetic factors play a major role in determining the thickness of hair strands. There are several factors that effect to the thickness of a hair. What causes the difference in the thickness of a hair? The cortex comprises about 80 % of the hair mass. The cuticle layer envelops the inner part of the hair shaft called the hair cortex. Moreover, the cuticle layer forms the perfect outer layer for every hair. Human hair consists of roughly 80 % of keratin (protein), about 10 to 15 % is water, and the remaining (5 to 10 %) are pigments, minerals, and lipids. 0.06 -0.08mm is average and 0.08-1mm then the hair is very thick. Specifically, the thin hair ranges from 0.04-0.06mm. Typically, the thickness of hair strands ranges from 1/1500 to 1/500 of an inch in diameter. What’s more, your genetic composition will cause a major difference in the hair from that of other people. We all have different thickness at different times or weather conditions or on different parts of our head. It’s that the diameter of the human hair which describes the thickness varies. If you have a larger diameter the hair is considered thick but if you have a thinner diameter than the hair is considered fine. But the density is the number of hairs you have in a square inch of your head. Most people think that thickness refers to volume and hair density. The thickness refers to the diameter of a strand of hair. The main purpose of hair on head keeps warm, regulates body temperature, provides a little cushioning for skull and beautify. It is primarily made of dead, keratinized cells. ![]() Hair is a keratinous filament growing out of the epidermis. What causes the difference in the thickness of a hair?.The beginning and end of the distribution are commonly defined by D 10 and D 90, although other D values can be used to define the cumulative distribution as well (e.g. D 50 defines the point where 50 % of the particles are smaller and 50 % bigger than that certain diameter. In either direction, the cumulative curve always ranges from 0 % to 100 %, with the middle point D 50 being the most commonly reported result of particle sizing by laser diffraction. This is done either from the smallest to the biggest diameter (called the "undersize curve") or in the opposite direction (called the "oversize curve"). To get this distribution, values for all previous classes are added to the next. For this reason, usually the cumulative distribution is analyzed. spikey, flat, etc.), so peak values are rather unreliable. However, there might be more peaks or the peak might be weakly defined (e.g. The D mode value defines the position of the highest peak. The basic particle size distribution might have one or more peaks for size classes, which indicate the most common particle sizes. The sample de-agglomerates (breaks down into smaller sized particles) as particles collide with each other or with the wall of the dispersion unit.Ī typical result of a laser diffraction measurement is shown in Figure 11. In dry mode the powder is put into motion either by compressed air or by gravity, creating a dry flow which is positioned in front of the laser beam. ![]() The liquid dispersion unit is usually equipped with a mechanical stirrer with adjustable speed and with a sonicator with adjustable duration and power. The sample keeps circulating until the measurement is done. ![]() In liquid mode the particles are dispersed in a liquid and pumped into a glass measurement cell which is placed in front of the laser. it should be measured in liquid mode if the final product is a liquid dispersion and in dry mode if the final product is a powder. Usually a sample should be analyzed in a state relevant to its application, i.e. This means that each particle should be visible as a single particle in front of the laser, moving through either liquid medium or air. In order to get a clear diffraction, it is necessary to have a proper dispersion of the sample.
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