#strengthening  the act of increasing the strength of something
  exclusion:  weakening
  supertype:  step-up__increase  the act of increasing something; "he gave me an increase in salary"
  subtype:  concentration.strengthening  strengthening the concentration (as of a solute in a mixture) by removing extraneous material
     subtype:  pervaporation  the concentration of a colloidal solution whose colloid will not pass through a semipermeable membrane; solution is placed in a bag of the membrane and the solvent is evaporated off

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