March 24, 2006 -- A torn ACL in the knee can be replaced -- but it can't be healed.A new technique now shows promise to change this. Doctors long ago gave up trying to repair a torn ACL (anterior cruciate ligament).arch 24, 2006 -- A torn ACL in the knee can be replaced -- but it can't be healed.
In chemistry, pH (/piËËeÉªtÊ/) is a numeric scale used to specify the acidity or basicity of an aqueous solution. It is approximately the negative of the logarithm to base 10 of the molar concentration, measured in units of moles per liter, of hydrogen ions.
pH is a measure of the acidic or basic (alkaline) nature of a solution. The concentration of the hydrogen ion [H+] activity in a solution determines the pH.Mathematically this is expressed as: pH = - log [H+]. The pH value is the negative power to which 10 must be raised to equal the hydrogen ion concentration.or example, 4 mg/l of iron would not present a toxic effect at a pH of 4.8. However, as little as 0.9 mg/l of iron at a pH of 5.5 can cause fish to die. Synergy has special significance when considering water and wastewater treatment.