METHOD OF GENERATING A GRADIENT FLOW HAVING A CONSTANT COMPOSITIONAL NOISE CHARACTERISTIC

摘要

Described is a method of generating a flow having a composition gradient. A plurality of pump strokes is generated for each pump in a plurality of pumps. Each pump stroke has an initiation time and provides a volume contribution of a liquid to be mixed in the flow according to the composition gradient for the flow. The pump strokes of the pumps are controlled so that a sum of the volume contributions of the liquids that occurs between consecutive initiations of one of the pumps is maintained at a constant value throughout the duration of the flow. For each pump, the flow rates and the times between stroke initiations can change as long as the sum of all volumes contributed between the consecutive initiations of one of the pumps is held constant. Advantageously, the method achieves a constant compositional noise characteristic throughout the duration of the flow.

主权项

1. A method of generating a flow having a composition gradient, the method comprising:
generating a plurality of pump strokes with a first pump, each of the pump strokes of the first pump having an initiation time and providing a volume contribution of a first liquid to a flow, the volume contributions of the first pump changing in time based on a contribution of the first liquid to the flow according to a predetermined composition gradient; and generating a plurality of pump strokes with at least one additional pump, each of the pump strokes of each of the additional pumps providing a volume contribution of an additional liquid to the flow, the volume contributions of each of the additional pumps changing in time based on a contribution of a respective one of the additional liquids to the flow according to the predetermined composition gradient, the pump strokes of the first pump and the additional pumps being controlled so that a sum of the volume contribution of the first liquid occurring between consecutive initiations of the first pump and volumes of the additional liquids contributed by the additional pumps between the consecutive initiations of the first pump is constant throughout a duration of the predetermined composition gradient.