Patent ID: 8178352

Claim:
A method for analyzing one or more characteristics of a use composition, the method comprising: providing a rotary valve analytical system comprising: a rotor having a rotor face, the rotor being rotatable about an axis perpendicular to the rotor face, wherein the rotor face has a plurality of openings, each of which extends into the rotor to form syringe barrels; a stator disposed coaxially with the rotor, the stator having a stator face in sealable, slidable, rotary contact with the rotor face, wherein the stator comprises a plurality of inlet passages and outlet passages passing therethrough, each inlet passage providing for fluid communication between a fluid source and an opening within the stator face, and each outlet passage providing for fluid communication between an opening within the stator face and a mixer line, wherein one or more of the fluid sources comprises a source of the use composition; a mixer having a plurality of inputs each in fluid communication with one of the mixer lines and an output in fluid communication with a sensor line; and a sensor coupled with the sensor line; rotating the rotor to a first position, such that the syringe barrels within the rotor are aligned with one or more of the inlet passages within the stator and the other openings within the stator face are sealed by the rotor face, wherein one or more of the aligned inlet passages are in fluid communication with the source of the use composition; drawing fluid into each of the syringe barrels from the aligned inlet passages; rotating the rotor to a second position, such that each of the syringe barrels are aligned with one of the outlet passages and the other openings within the stator face are sealed by the rotor face; driving fluid from the syringe barrels and through the aligned fluid outlet passages into the mixer lines; mixing the fluids in the mixer resulting in a sample mixture within the sensor line; measuring one or more properties of the sample mixture with the sensor, the properties being indicative of the one or more characteristics of the use composition; and determining the one or more characteristics of the use composition from the measurement.