Abstract:
The present invention provides a nitrogen oxide gas sensor based on sulfur-doped graphene and a preparation method therefor. The method comprises the following steps: 1) providing graphene and a micro heater platform substrate, and transferring the graphene onto the micro heater platform substrate; 2) putting the micro heater platform substratecovered with the graphene into a chemical vapor deposition reaction furnace; 3) performing gas feeding and exhausting treatment to the reaction furnace by using inert gas; 4) simultaneously feeding inert gas and hydrogen gas into the reaction furnace at a first temperature; 5) feeding inert gas, hydrogen gas and sulfur source gas into the reaction furnace at a second temperature for reaction to perform sulfur doping to the graphene (21); and 6) stopping feeding the sulfur source gas, and performing cooling in a hydrogen gas and insert gas shielding atmosphere. The preparation method provided by the present invention may adopt a wafer level substrate, which can realize wafer level preparation, can achieve the level of batch preparation and can greatly reduce the production cost; and the prepared gas sensor has relatively high sensitivity and selectivity to nitrogen oxide gas molecules.
Abstract:
A NO X sensor electrode material includes a composition of Ba (1-X) A X Fe (12-Y )B Y O 19 . Constituent A and constituent B are doping elements. Constituent A is selected from the group consisting of Bi, La and Pb and X is a real number where 0‰¤X
Abstract:
In order to simplify an inspection of an in-vehicle exhaust gas analysis system as well as to inspect the entirety of the system combining a flowmeter and exhaust gas analyzer, an in-vehicle exhaust gas analysis system 10, which is provided with a flowmeter 2 to measure a flow rate of exhaust gas, and an exhaust gas analyzer 3 to analyze a concentration of a measurement target component contained in the exhaust gas, includes a standard gas supply mechanism 5 to supply a standard gas containing a predetermined component to the flowmeter 2 and the exhaust gas analyzer 3. The system 10 is configured to include a detected mass calculation section 63 to calculate a detected mass of a predetermined component by using a flow rate obtained by the flowmeter 2 and a concentration of the predetermined component obtained by the exhaust gas analyzer 3; a supply mass acquisition section 64 to acquire a supply mass of the predetermined component supplied from the standard gas supply mechanism 5 to the flowmeter 2 and the exhaust gas analyzer 3; and a mass comparison section 65 to compare a detected mass calculated by the mass calculation section 63 and a supply mass acquired by the supply mass acquisition section 64.
Abstract:
A molecular detection apparatus includes: a collection unit collecting detection target gas containing molecules (2) to be detected; a detector (20) including detection cells (201) having an organic probe (22) provided at a sensor unit (21), for example a graphene (26) field-effect transistor, the organic probe capturing the collected molecule to be detected; and a discriminator discriminating the molecule to be detected by a detection signal generated by the molecule being captured by the organic probe. The detection cell has the organic probe containing a phosphonic acid structure or phosphoric acid structure. The organic probe comprises a polycyclic aromatic hydrocarbon group as base portion, a connecting portion and a head portion containing thze phosphonic or phosphoric acid structure.
Abstract:
A diagnostic device for a sensor 100 provided in an exhaust passage 11 of an internal combustion engine 10 of a vehicle and detecting nitrogen compounds in exhaust gas, the diagnostic device including an offset diagnosis unit 42 which diagnoses, during deceleration of the vehicle in which the internal combustion engine 10 stops fuel injection, an offset amount of a sensor value of the sensor 100 from a zero point based on the sensor value of the sensor value, and a diagnosis prohibition unit 44 which prohibits the diagnosing of the offset amount when a flow rate of the exhaust gas of the internal combustion engine 10 rapidly increases while the offset amount is diagnosed by the offset diagnosis unit 42.
Abstract:
The multiple gas detection device 1 comprises: a first cell part provided with a first electrochemical cell 51; a second cell part provided with a second electrochemical cell 52; a third cell part provided with a third electrochemical cell 53; an inlet diffusion controller 15 controlling diffusion of measured gas; and a measured gas chamber 30 into which the measured gas flows through the inlet diffusion controller 15. The first cell part is configured to selectively detect a concentration of NO x or ammonia contained in measured gas in the measured gas chamber 30. The second cell part is configured to discharge oxygen contained in measured gas in the measured gas chamber 30 and convert NO 2 and ammonia contained in measured gas in the measured gas chamber 30 to NO. The third cell part is configured to detect a concentration of NO contained in measured gas in the measured gas chamber 30.
Abstract:
An apparatus includes an engine output module that determines an engine output power parameter for an engine. The apparatus includes an output power threshold module that determines if the engine output power parameter is below an output power threshold. The apparatus includes a NOx module that determines a nitrogen oxide (“NOx”) efficiency of a selective catalytic reduction (“SCR”) system in response to the output power threshold module determining that the determined engine output power parameter is below the output power threshold. The SCR system is in exhaust receiving communication with the engine. The apparatus includes a NOx threshold module that determines if the NOx efficiency is below a NOx efficiency threshold, and a NOx warning module that sends a NOx alarm signal in response to the NOx threshold module determining that the NOx efficiency is below the NOx efficiency threshold.