A contact lens is a lens placed on the cornea of the eye.
Importance of buffers in contact lens products:
Buffers: They aim to keep the pH of the solutions at values between 6.6 and 7.8 in order to maintain the lens parameters and the effectiveness of the solutions. They are made by the combination of an acid and its sodium salt (phosphate and acetate for example). Borate and citrate buffers are used.
Importance of isotonicity in contact lens products:
The solution composed by isotonic saline solution.
Isotonia is expressed by osmolarity or cryoscopic lowering
- 0.236 to 0.446 mOsmoles / l (increases during the day)
- If the osmolarity of the mixture is different from that of the tears, it causes discomfort and irritation
• Increased tear secretion
• Increase the blink frequency
- If hypotonia, entry of water to the epithelial cells, if hypertonia: inverse
- Osmolarity restored 1 or 2 minutes after instillation
So it should have a similarities because the words makes sense
<span>Desertification is the cancer of the earth,” Argentine geographer Elena Abraham told IPS. “It is a process of degradation that does not manifest itself in spectacular ways but furtively advances, and by the time it is visible there is nothing to be done, and people have to move away, in search of an alternative.”</span>
Well there are three reasons
it drains into rivers, streams, etc. or
it seeps into soil and gather underground as ground-water
or
falls into high mountains and freeze and in the summer it will melt and flows into the rivers
