Выражение встречается в следующем контексте:
Linearity and Range
Experiment: A series of standard preparations of working standard will be prepared over a range of 50% to 150% of the working standard concentration of *** in ***. Since the working concentration is 20.0µg/mL the range proposed is about 10.0µg/mL to 30.0µg/mL
Preparation of linearity stock solution:
Weigh accurately about 20.0mg working standard and transfer into a 100mL volumetric flask. Add 70.0mL of Tetrahydrofuran and sonicate to dissolve. Cool to room temperature. Dilute to volume with Tetrahydrofuran and mix. This is linearity stock solution-I. From this prepare the linearity solution as given below in table No.3

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