| hardness |
A property of water which causes an increase in the amount of soap that is needed to produce foam or lather and that also produces scale in hot water pipes, heaters, boilers and other units in which the temperature of water is increased materially. Hardness is produced almost completely by the presence of calcium and magnesium salts in solution. The following scale may assist in appraising water hardness, measured by weight of dissolved salts (in milligrams) per unit (in liters) of water:
출처: www.norfolk.gov/Utilities/quality/Terms.asp
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| hardness |
A measure of a material's resistance to indentation. For wire, normally the Rockwell Test or one of the superficial hardness tests are used.
출처: www.branfordwire.com/glossary.htm
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