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unknown facts about hair
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CHEMISTRY OF HAIR
ABDUR RAHMAN (XII-B)
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"There is no higher or lower
knowledge, but one and only one,
flowering out of experimentation."
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H.O.D External Internal
This is to certify that Mr. ABDUR RAHMAN AMMAR from class XII-B, Roll no.12212 has completed his investigatory project by taking into consideration all the formalities.
Examiner Examiner
CERTIFICATE
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I would like to express my sincere gratitude to my chemistry mentor Mr. S.K. PAUL for his vital support, guidance and encouragement without which this project would not have come forth from my side.
I would also like to express my heartily gratitude to principal Mrs. LILLY SIDDHARTAN for providing support to finish project on time.
I wish to thanks my PARENTS for their undivided support & interest who inspired me & encouraged me to go my own way, without which I would be unable to complete my project. And at last by no means the least I would thank to ALMIGHTY who made all the things possible.
ACKNOWLEDGEMENT
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INDEX
INTRODUCTION
INVESTIGATION
REMEDIES
FAQ’s
AIM
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AIM:-
• investigating oN hAIR ,iTS cHEMISTRY ,tENSILE ,aN oTHER fACTORS.
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INTRODUCTION
• A hair can be defined as a slender, thread-like outgrowth from a follicle in the skin of mammals
• Hair is composed of structural protein α-keratin
• This protein exists in α-helical form and is rich in cystine , oxidized form of amino acid cysteine
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Cuticle The cuticle is a
translucent outer layer of the
hair shaft consisting of scales
that cover the shaft.
The medulla is a central
core of cells that may be
present in the hair. If it is filled
with air, it appears as a black
or opaque structure under
transmitted light, or as a white
structure under reflected light.
Cortex The cortex is the main
body of the hair composed of
elongated and fusiform
(spindle-shaped) cells.
A hair grows from the papilla
and with the exception of that
point of generation is made up
of dead, cornified cells.
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INVESTIGATIONS
tensile strength • The point of failure i.e the time at which it breaks on
providing stress, is of much interest and is typically called its "Ultimate Strength" or UTS on the chart.
• Typically, the testing involves taking a small sample with a fixed cross-section area, and then pulling it with a tensometer, gradually increasing force until the sample breaks.
• When testing metals, indentation hardness correlates linearly with tensile strength. This important relation permits economically important nondestructive testing of bulk metal deliveries with lightweight, even portable equipment, such as hand-held Rockwell hardness testers.
• Stress is force acting unit cross section area thus, Tensile stress = F/A (unit-pascal).• Strain is extension per unit length thus, Tensile strain = e/l.
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Sr. No. Material tensile strength
1 Human Hair 200
2 Human Skin 20
3 Ordinary steel 400
4 Nylon Thread 75
5 Spider web (dragline) 1200
6 Carbon nanotube 62000
7 Carbon Fiber 6370
Obserevation
Sufficient tensile strength helps in maintaining toughness of hair, thereby a good hair breakage index which enables it long lasting.
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Effect of shaving and cutting hair
Cutting with scissors, shaving has no effect on hair growth. ( The myth was exploded by Dr. Mildred Trotter* at
the Washington University School of Medicine )
Reasons for the Disbelief 1. The shortness of the shaft of a shaved
hair allows changes in its length to be noticed more easily than noticing increase
in length of beard.2. Apparent coarseness is caused by the
short, shaved hairs being held more erect by the follicles clasped firmly around them.
* Under Dr. Trotter¹s observation, three girls shaved their legs from knee to ankle, twice a week for a period of eight months. At the end of this time, microscopic examination revealed that there was
absolutely no increase in the diameter or color of the hairs before or after the shaving period.
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Excessive washing of hair causes hair
loss/dryness Frequency of washing doesn’t harm hair. Although the
recommendation is three times a week.
Conditioner helps repair split ends
Conditioner can’t "repair" damaged hair. What it can do is smooth down the cuticle and make hair seem in better condition. A good conditioner can also prevent
damage from occurring in the first place.
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Sleeping with wet hair causes scalp
fungus Scalp or fungal diseases can’t be caught from sleeping with wet scalps. Scalp infections require prior involvement with infected
sources such as humans, tainted hair care tools or animals. Scalp fungus (tinea capitis) mainly affects children, whose immune systems
make them more susceptible to skin infections.
Smoking causes gray hair
According to J. G. Mosley of the Leigh Infirmary in Lancashire, England in an article in Science News (January 11, 1997) smokers are
four times more likely to have gray hair than non-smokers. Even worse, smoking has been conclusively linked to accelerated hair loss.
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Brushing your Hair
There is a school of thought that brushing your hair is good for it, even compared with combing. The
reasoning is that brushing is just like massaging the scalp, which will increase blood circulation, and
hence stimulate hair growth. This is also nonsense; in fact too much brushing could damage the hair
by causing split ends
Split ends will travel
Uncut split ends can travel up the hair shaft towards the roots. Hair that is not tended to,
over time, may develop splits that migrate and split all or part of the entire hair. Some
ends can actually tear multiple times so that your split ends have splits.
Steroids have no side effects on
hair
Bodybuilders beware! Anabolic steroids are very potent chemicals that have some
treacherous side effects including acceleration of hair loss. The problem is that these side
effects are usually delayed by several years.
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1.The cause of the most common type of hair loss is physical or emotional stress.
2.According to the mayo clinic. Doctors refer to this type of hair loss as telogen effluvium. It occurs when stress causes a large amount of growing hairs to settle
into a resting phase. Within a few months, the hairs suddenly seem to
appear everywhere during hair washing, combing or brushing. The hair will grow back, but not until the stressor has been
resolved.
3.Infection like dissecting cellulitis, fungal infections (such as tinea capitis),folliculitis, secondtemporary or
permanent hair loss can be caused by several medications, including those for
blood pressure problems, diabetes, heart disease and cholesterolary syphilis
also causes hair loss
Hair loss (alopecia)
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2. Finasteride (propecia) is used in male-pattern hair loss in a pill form taken on a daily basis. It is not indicated for women and is not recommended in pregnant women. Treatment is effective within six to eight months of treatment. Side effects include decreased sex drive, erectile dysfunction, ejaculatory dysfunction, gynecomastia, and myopathy, hair loss resumes again.. Once treatment is stopped
1.Minoxidil (rogaine) is a nonprescription medication approved for male pattern baldness and alopecia areata. In a liquid or foam, it is rubbed into the scalp twice a day. However, only 30–40% of patients experience hair growth most frequent side effects are mild scalp irritation, allergic contact dermatitis, and increased facial hair
REMEDIES
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3. Immunosuppressants applied to the scalp have been shown to temporarily reverse alopecia areata, though the side effects of some of these drugs make such therapy questionable.
4. Hormonal modulators (oral contraceptives or antiandrogens such as spironolactone and flutamide) can be used for female-pattern hair loss associated with hyperandrogenemia.
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How can hair stretch? Before breaking, a hair undergoes changes. For example, by delicately handling a reasonably long hair it can easily be shown that it behaves like a piece of elastic; after extending slightly, it returns to its original length.
The use of the extensiometer which progressively stretches a hair at the rate of 1 cm per minute allows precise study of the modifications hair undergoes before it breaks.
Thus, for lengthening of up to 5%, hair is elastic .
FAQ’s
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What is keratin?
a fibrous protein forming the main structural constituent of
hair, feathers, hoofs, claws, horns, etc.
what is cysteine?
Cysteine is an α-amino acid with the chemical formula
HO2CCHCH2SH. It is a semi-essential amino acid, which
means that it can be biosynthesized in humans.
Formula: C3H7NO2S
Molar mass: 121.16 g/mol
IUPAC ID: Cysteine
Melting point: 240 °C
Soluble in: Water
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BIBLIOGRAPHY• www.google.com• www.wikipedia.en• www.instron.com• www.zapahair.com• www.hair-science.com• www.wikhow.com• www.disabled-worled.com• Askville.amazon.com• www.Studyhealth.com