Abstract: According to an example aspect of the present invention, there is provided an apparatus comprising a volume for receiving a gas sample; and an ultrasonic transducer; wherein the ultrasonic transducer is caused to generate a standing wave to the volume, said standing wave comprising at least one particle trapping zone for trapping particles carried by the gas sample, and to release particles trapped to the at least particle trapping zone by decreasing power of the standing wave to at least one lower power level and/or switching off the standing wave.

Abstract: A microelectromechanical (MEMS) resonator includes a resonator structure having a plurality of beam elements and connection elements with certain geometry, where the plurality of beam elements are positioned adjacent to each other and adjacent beam elements are mechanically connected to each other by the connection elements, where the geometry of the beam elements or the connection elements varies within the resonator structure.

Abstract: A MEMS (microelectromechanical system) resonator with a material layer of single-crystalline silicon, at least one layer made of material with low thermal diffusivity to reduce thermoelastic dissipations in the MEMS resonator, a layer of piezoelectric material, and a layer made of electrically conducting material. The said-layer with low thermal diffusivity is between the single-crystalline silicon layer and the piezoelectric layer, or between the piezoelectric layer and the electrically conducting layer. The use of a material layer of low thermal diffusivity.

Abstract: A microelectromechanical (MEMS) resonator includes a resonator structure having a plurality of beam elements and connection elements with certain geometry, where the plurality of beam elements are positioned adjacent to each other and adjacent beam elements are mechanically connected to each other by the connection elements, where the geometry of the beam elements or the connection elements varies within the resonator structure.

Abstract: A microelectromechanical (MEMS) resonator includes a resonator structure having a plurality of beam elements and connection elements with certain geometry, where the plurality of beam elements are positioned adjacent to each other and adjacent beam elements are mechanically connected to each other by the connection elements, where the geometry of the beam elements or the connection elements varies within the resonator structure.

Abstract: According to an example aspect of the present invention, there is provided an apparatus, comprising: a channel for receiving gas; thermophoretic unit configured to create a temperature gradient in the channel, and a particle detector for detecting particles in the gas on the basis of particle landing positions in the channel.

Abstract: According to an example aspect of the present invention, there is provided an apparatus comprising a microelectromechanical, MEMS, capacitor comprising two plates and a gap between the plates, a gas conveyor configured to cause gas to flow through the gap, and readout circuitry configured to measure a capacitance of the MEMS capacitor.

Abstract: According to an example aspect of the present invention, there is provided an apparatus comprising a volume for receiving a gas sample; and an ultrasonic transducer; wherein the ultrasonic transducer is caused to generate a standing wave to the volume, said standing wave comprising at least one particle trapping zone for trapping particles carried by the gas sample, and to release particles trapped to the at least particle trapping zone by decreasing power of the standing wave to at least one lower power level and/or switching off the standing wave.

Abstract: A sensor (1) comprises a transducer (2), a base plate (3) comprising a space (4) for accommodating the transducer (2), and a silicon-on-insulator plate (5) on top of the base plate (3). The base plate (3) forms a frame for the transducer (2) and the silicon-on-insulator plate (5) at least partly defines a horizontally and vertically extending cavity (6) arranged in connection with the transducer (2). The sensor (1) further comprises a top element (7) on top of the silicon-on-insulator plate (5) for terminating the cavity (6).

Abstract: A capacitive pressure sensor for an internal combustion engine is provided having a housing having a bottom surface, variable capacitor and circuitry. The variable capacitor is formed by a stationary electrode and an elastically bendable electrode. Pressure exerted on the bottom surface acts to bend the elastically bendable electrode. This bending alters the capacitance of the variable capacitor. The circuitry is configured to generate a signal based on the variable capacitance of the variable capacitor. This capacitance is representative of the pressure exerted on the bottom surface.

Abstract: A capacitive pressure sensor for an internal combustion engine is provided having a housing having a bottom surface, variable capacitor and circuitry. The variable capacitor is formed by a stationary electrode and an elastically bendable electrode. Pressure exerted on the bottom surface acts to bend the elastically bendable electrode. This bending alters the capacitance of the variable capacitor. The circuitry is configured to generate a signal based on the variable capacitance of the variable capacitor. This capacitance is representative of the pressure exerted on the bottom surface.