2000 B.C - The first recorded (The Susruta Samhita, Sanskrit writing) water purification began with the Egyptians. It is said that impure water should be boiled over a fire, heated in the sun, have a hot iron dipped into it or purified by filtration through sand and course gravel.
A major step in the development of desalination technologies came in the 1940s during World War II when various m
charges in the polarized C-F bond
C-F bond
: strongest bond in
organic chemistry
: high energy bond
Two most studied compounds
PFOS (Perfluorooctanesulfonic acid)
PFOA (Perfluorooctanoic acid)
Other PFCs include:
PFNA(Perfluorononaoic acid)
PFBS(Perfluorobutanesulfonic acid)
POSF(Perfluorooctanesulfonyl fluoride)
PFOSA(Perfluorooctanesulfonamide)
FC-75
water?
Nedda, get me some water, please.
Youre going to be OK.
- Im fine.
- Ill tell you when youre fine.
- Whats wrong?
- Hes sending me home.
Twice in one week?
Dizzy spells, not good.
Its my medication.
- Nick, I got a cab.
- Good.
Heres $ for the cab,
you take Helen home.
- What about me?
- You take the bus.
Ill call you this afternoon.
That woman at table five
stiffed me last week.
OK, thank
fluoridated toothpastes, these hard tissues progressively break down, producing dental caries (cavities, holes in the teeth).
2) Stomatitis
Stomatitis is an inflammation of the mucous lining of any of the structures in the mouth, which may involve the cheeks, gums, tongue, lips, throat, and roof or floor of the mouth. The inflammation can be caused by conditions in the mouth itself, such a