The invention relates to a method for analysing hydrocarbons, with the implementation of a gas chromatography separation according to a first controlled temperature profile, to separate a sample into a plurality of analytes and the detection of at least one of said analytes by measurement of a variation of the resonance frequency of at least one resonator of nano-electromechanical system (NEMS) type covered with a functional layer made to vibrate at the resonance frequency thereof, under the effect of an adsorption or desorption of the analyte by the functional layer, the resonator being subjected to a second controlled temperature profile, lower than the first profile.

The invention relates to a method for analysing hydrocarbons, with the implementation of a gas chromatography separation according to a first controlled temperature profile, to separate a sample into a plurality of analytes and the detection of at least one of said analytes by measurement of a variation of the resonance frequency of at least one resonator of nano-electromechanical system (NEMS) type covered with a functional layer made to vibrate at the resonance frequency thereof, under the effect of an adsorption or desorption of the analyte by the functional layer, the resonator being subjected to a second controlled temperature profile, lower than the first profile.

A system for sensing a fluid. The system including a fixed object; a first transducer generating a first sound wave in a horizontal direction and to detect a first echo of the first sound wave from the fixed object; a second transducer generating a second sound wave in a vertical direction; a temperature sensor detecting a temperature of the fluid; and a controller. The controller configured to produce a first signal to drive the first transducer to produce the first sound wave, produce a second signal to drive the second transducer to produce the second sound wave, receive a first indication of the detected first echo, receive a second indication of the detected second echo, receive a temperature indication, determine a quality of the fluid based on the first indication and the temperature indication, and determine a quantity of the fluid based on the second indication.