A vehicle and a method of displaying nitrogen oxide emissions of the vehicle to accurately detect and easily display an amount of nitrogen oxide emitted from the vehicle includes receiving nitrogen oxide concentration values of exhaust gas in the vehicle, calculating an average value of the nitrogen oxide concentration based on the nitrogen oxide concentration values, calculating an amount of nitrogen oxide in the exhaust gas based on the average value of the nitrogen oxide concentration, calculating a nitrogen oxide index of the exhaust gas based on the amount of the nitrogen oxide, and displaying the calculated nitrogen oxide index for each of a plurality of predetermined sections through a display unit of a cluster of the vehicle.

A method of measuring a concentration of NO.sub.2 in a gaseous mixture using a multimode laser beam that covers a tunable spectral range with a width of no more than 5 nm, wherein the multimode laser beam provides a high resolution transmittance spectrum at an absorption cross section of NO.sub.2 molecules, and a system for measuring the concentration of NO.sub.2 in the gaseous mixture. Various combinations of embodiments of the system and the method are provided.

A battery-powered analyte sensing system includes a printed battery and an analyte sensor. The printed battery includes an anode composed of a non-toxic biocompatible metal, a first carbon-based current collector in electrical contact with the anode, a three-dimensional hierarchical mesoporous carbon-based cathode, a second carbon-based current collector, and an electrolyte layer disposed between the anode and the cathode, the electrolyte layer configured to activate the printed battery when the electrolyte is released into one or both the anode and the cathode. The analyte sensor includes a sensing material and a reactive chemistry additive in the sensing material.

The invention is directed to a chemically robust, highly-selective, low power sensor that can be used for the direct electrical detection of mixed gases. In particular, metal-organic frameworks (MOFs) offer exceptional chemical and structural tunability as mixed-gas capture materials. As an example of the invention, the influence of interfering gases on trace NO.sub.2 detection in a simulated flue gas stream was investigated. The unique interaction of NO.sub.2 with the MOF's metal center leads to orders of magnitude decrease in MOF resistance. More broadly, the coadsorption of specific gases (e.g., H.sub.2O, SO.sub.2) can be beneficial to the electrical detection of the target gas (e.g., NO.sub.2), and careful electrical measurements can discern their presence independent of the target gas.

A method of operating an engine is provided. The method includes determining a temperature and a pressure of intake air, and a temperature and a pressure of exhaust generated by the engine. The method includes determining a work performed by the engine based at least on an engine speed of the engine, and determining heating losses of the engine. The method includes determining an enthalpy of the intake air based at least on the work, the heating losses, a heating value of a fuel used for combustion within the engine, and the temperature and the pressure of the exhaust. The method includes determining a humidity value of the intake air based on the enthalpy, temperature and pressure of the intake air and determining an amount of NOx based on the humidity value. The method further includes controlling an operation of the engine based on the determined amount of NOx.

An improved NO.sub.x sensor with an NH.sub.3 oxidation catalyst. A sensor module may include a support component, a NO.sub.x sensing material positioned on the support component, and an NH.sub.3 oxidation catalyst. The NH.sub.3 oxidation catalyst may be layered on top of the NO.sub.x sensing material or the NH.sub.3 oxidation catalyst may be positioned upstream of the NO.sub.x sensing material such that the NH.sub.3 oxidation catalyst selectively converts NH.sub.3 to N.sub.2 while permitting NO.sub.x through to the NO.sub.x sensing material.

A nitrogen oxide sensor includes a measured gas chamber, a sensor cell, a pump cell, a voltage application circuit, a sensor output detector, a voltage control part, a concentration calculation part, a temperature estimation part, an air-fuel ratio estimation part, and a time calculation part calculating a cumulative value of time periods when the temperature of the pump cell is within a predetermined temperature region and the air-fuel ratio of the measured gas is leaner than the stoichiometric air-fuel ratio as a first cumulative time period. The concentration calculation part calculates the NOx concentration in the measured gas higher with respect to the output of the sensor cell when the first cumulative time period is relatively long compared with when the first cumulative time period is relatively short.

A sensitive, compact detector measures total reactive nitrogen (NO.sub.y), as well as NO.sub.2, NO, and O.sub.3. In all channels, NO.sub.2 is directly detected by laser diode based cavity ring-down spectroscopy (CRDS) at 405 nm. Ambient O.sub.3 is converted to NO.sub.2 in excess NO for the O.sub.3 measurement channel. Likewise, ambient NO is converted to NO.sub.2 in excess O.sub.3. Ambient NO.sub.y is thermally dissociated at 700 C to form NO.sub.2 or NO in a heated quartz inlet. Any NO present in ambient air or formed from thermal dissociation of other reactive nitrogen compounds is converted to NO.sub.2 in excess O.sub.3 after the thermal converter. The precision and accuracy of this instrument make it a versatile alternative to standard chemiluminescence-based NO.sub.y instruments.

The present disclosure provides a system and method for monitoring diesel vehicle emissions based on big data of remote sensing. The monitoring system includes a vehicle remote sensing data monitoring platform, a host computer, an emission remote sensing instrument, a vehicle driving state monitor, an information display screen and a license plate camera. The emission remote sensing instrument is used to acquire information of a pollutant in an exhaust plume. The vehicle driving state monitor is used to acquire a vehicle speed and acceleration. The license plate camera is used to capture license plate information. The host computer is used to process and calculate vehicle cycle and emission information. The vehicle remote sensing data monitoring platform is used to determine a high-emission vehicle, and pre-store information of all diesel vehicles, different driving cycle bins of each type of diesel vehicles and high-emission thresholds set for different bins.

Described is a personal device and methods for measuring the concentration of an analyte in a sample of gas. The device and method may utilize a chemically selective sensor element with low power consumption integrated with circuitry that enables wireless communication between the sensor and any suitable personal electronic device such as a smartphone, tablet, or computer. In preferred form, the sensor circuitry relies upon the quantum capacitance effect of graphene as a transduction mechanism. Also in preferred form, the device and method employ the functionalization of the graphene-based sensor to determine the concentration of an analyte in exhaled breath.