An aftertreatment system for treating constituents of an exhaust gas produced by an engine includes a heater configured to selectively heat the exhaust gas entering the aftertreatment system. An aftertreatment component is disposed downstream of the heater. A gas sensor is disposed downstream of the heater and upstream of the aftertreatment component. The gas sensor comprises a sensing element, and a heating element configured to selectively heat the sensing element to an operating temperature of the sensing element.

An exhaust gas treatment device includes a housing having a wall. The wall of the housing defines an interior chamber. A substrate is supported by the housing within the interior chamber of the housing. The substrate extends along a longitudinal axis. The substrate includes a flow through structure that allows the flow of exhaust gas to flow through the substrate. The substrate includes a catalytic composition disposed thereon for reacting with the flow of exhaust gas. The substrate includes a cavity, extending along a cavity axis, which is transverse to the longitudinal axis of the substrate. A sensor is attached to the housing. The sensor includes a probe that at least partially extends into the cavity of the substrate, for sensing a gaseous component in the flow of exhaust gas. The cavity mixes the flow of exhaust gas and directs the exhaust gas toward the probe of the sensor.

Provided is a method for diagnosing whether an oxidation catalyst has degraded, based on an output value from one diagnostic sensor with higher accuracy. When a ratio of nitrogen monoxide that is oxidized by a catalyst and discharged downstream of the catalyst as nitrogen dioxide, with respect to nitrogen monoxide contained in an exhaust gas supplied upstream of the catalyst in an exhaust path is defined as a NO conversion rate, a diagnostic sensor configured to output an electromotive force corresponding to the NO conversion rate as a diagnostic output is provided downstream of the catalyst in the exhaust path, and whether the catalyst has degraded beyond an acceptable limit is diagnosed by comparing the diagnostic output with a threshold value predetermined depending on a temperature of the catalyst.

A method for NOx emission control during start of a vehicle comprising an exhaust aftertreatment system, an engine, and a NOx sensor is provided. The method includes determining a temperature of the NOx sensor; if the determined temperature of the NOx sensor is below a predetermined threshold, initiating heating of the NOx sensor, and performing a preventive action for delaying engine start until a determined temperature of the NOx sensor exceeds or is equal to the predetermined threshold.

In an example of a selective, real-time gas sensing method, a gas sample, potentially including a specific gas molecule to be sensed, is supplied to an interface between a working electrode and an ionic liquid electrolyte. Based on at least one unique electrochemical reaction of the specific gas molecule to be sensed, a driving force is implemented to initiate a series of reactions involving the specific gas molecule. In response to the implementation of the driving force, a signal indicative of the specific gas molecule is monitored for.

A first gas sensor having a first sensor element includes a first protective cover that protects the first sensor element, and a second gas sensor having a second sensor element includes a second protective cover that protects the second sensor element. The first protective cover is coated with an oxidation catalyst for one target component from among a plurality of target components, and the second protective cover is coated with an inert catalyst for the one target component.

A condensate discharge system for an exhaust gas measuring device. The condensate discharge system includes a condensate separator in which a positive pressure prevails, an outflow line in which atmospheric pressure prevails, a connecting line, and an intermediate reservoir in which the positive pressure prevails. The intermediate reservoir is arranged between the condensate separator and the outflow line and is directly connected to the condensate separator via the connecting line. The intermediate reservoir includes a float valve via which a condensate is dischargeable into the outflow line.

A method for ascertaining an exhaust gas composition of an exhaust gas of an internal combustion engine with regard to an ammonia fraction and a nitrogen oxides fraction in an exhaust gas system including an SCR catalytic converter. The method includes detecting, using a sensor, a first signal whose magnitude is a function of the nitrogen oxides fraction of the exhaust gas upstream from the SCR catalytic converter, detecting using a sensor a second signal whose magnitude is a function of the ammonia fraction and the nitrogen oxides fraction of the exhaust gas downstream from the SCR catalytic converter, storing the two signals over an observation period, and ascertaining the ammonia fraction and optionally the nitrogen oxides fraction of the exhaust gas downstream from the at least one SCR catalytic converter using a calculation rule that uses the two signals during the observation period as input variables.

A system, apparatus, and method are provided for preventing the accumulation of particulate matter such as combustion soot on sensors positioned in exhaust gas conduits of internal combustion engines. In an embodiment, the apparatus includes a device for deflecting soot deposits from sensor surfaces. In an embodiment, the apparatus includes a device employing a surface acoustic wave generator for dislodging soot accumulation or measuring soot accumulations to trigger burn-off events. In an embodiment, an injector injects pressurized bursts of gas toward a sensor surface to dislodge particulate matter. In an embodiment, charged electrodes attract charged particles of soot from the exhaust gas flow to form deposits that are then subject to burn-off events.

A segmented, heated urea mixer and an exhaust system to control NOx emission from combustion engines comprising a plurality of elements, at least one element independently heatable by an external power source to a temperature above a temperature of another element. A method of using the exhaust gas mixer and an exhaust gas mixer system further comprising a controller is also disclosed.