G01N27/4065

METHOD OF PRODUCING GAS SENSOR ELEMENT
20210025845 · 2021-01-28 ·

There is provided a method of producing a gas sensor element capable of detecting a concentration of specific ions based on a limiting current passing between a first electrode and a second electrode according to a concentration difference of the specific ions. The method includes a temperature raising step, a current measuring step and a control step. In the temperature raising step, a heater is energized to raise temperature of a solid electrolyte. In the current measuring step, a voltage is applied across the first and second electrodes and to measure a limiting current. In the control step, a part of a diffusion resistance layer is removed from the gas sensor element by using an ultrashort pulsed laser to control a diffusion length that is a length of an introduction path to maintain the limiting current to be within a final standard range.

Gas sensor with a pump cell

A gas sensor includes an electrochemical cell having a solid electrolyte layer disposed between a sensing electrode and a reference electrode; a heater disposed in thermal communication with the electrochemical cell, the heater having a positive heater lead and a negative heater lead; a reference gas channel; a reference chamber in fluid communication with the reference electrode; a pump cell having a first pump cell electrode in fluid communication with the reference gas channel and also having a second pump cell electrode in fluid communication with the reference chamber. The first pump cell electrode has a pump cell first lead which forms a first electrical junction with either the positive heater lead and the negative heater lead and the second pump cell electrode has a pump cell second lead which forms a second electrical junction with the same heater lead as the pump cell first lead.

Sensor control device and gas detection system

In a sensor control device which controls a sensor, a first filter unit extracts a first filtered signal obtained by attenuating a frequency component higher than a first cutoff frequency from a digital signal indicating a current-application control value for a pump current, and a second filter unit extracts a second filtered signal obtained by attenuating a frequency component higher than a second cutoff frequency from the first filtered signal. A cutoff frequency setting unit sets at least one of the first cutoff frequency and the second cutoff frequency such that the sensor control device can control at least two types of sensors.

SENSOR DEVICE AND MEASUREMENT APPARATUS
20200333280 · 2020-10-22 · ·

To provide a sensor device and a measurement apparatus that are able to appropriately control a temperature of a sensing region where a potential is measured. Provided is a sensor device that includes an electrode array exposed to a sensing region, at least one or more wiring line layers provided in a layer same as the electrode array, a temperature determiner that determines a temperature of the sensing region on the basis of an electric resistance of the wiring line layer, and a temperature controller that controls the temperature of the sensing region on the basis of the temperature of the sensing region determined by the temperature determiner.

Concentration computation apparatus

A microcomputer calculates the concentration of ammonia contained in exhaust gas. The microcomputer repeatedly obtains from a first ammonia detection section a first ammonia electromotive force EMF1 whose value changes with both the concentrations of ammonia and a flammable gas contained in the exhaust gas. The microcomputer outputs, as ammonia concentration information at the present point in time, ammonia concentration information representing the ammonia concentration at the point 0.5 sec prior to the present point in time. The microcomputer sets a rich spike flag Fs when a first ammonia electromotive force change amount EMF1 is smaller than a value obtained by multiplying a start determination value by 1. When the rich spike flag Fs is set, the microcomputer sets the ammonia concentration information at the present point in time to the value of the ammonia concentration information at the point immediately before the rich spike flag Fs is set.

ELECTROCHEMICAL GAS SENSOR WITH VARYING BIAS VOLTAGE AND ENVIRONMENTAL COMPENSATION
20200319137 · 2020-10-08 ·

An electrochemical cell for sensing gas has added mechanical support for the working electrode to prevent flexure of the working electrode due to pressure differentials. The added mechanical support includes: 1) affixing a larger area of the working electrode to the body of the cell; 2) a gas vent to a cavity of the body to equalize pressures; 3) a rigid electrolyte layer abutting a back surface of the working electrode; 4) infusing an adhesive deep into sides of the porous working electrode to enhance rigidity; 5) supporting opposing surfaces of the working electrode with the rigid package body; and 6) other techniques to make the working electrode more rigid. A bias circuit is also described that uses a controllable current source, an integrator of the varying current, and a feedback circuit for supplying a voltage to the counter electrode and a bias voltage to the reference electrode.

System, Apparatus And Method For Sensing, Detecting And Effecting In A Micro-To-Nano Environment
20200319165 · 2020-10-08 ·

An apparatus that is m- or nm-scale in size and can include integrated circuitry logic based on sub 10 nm SIA transistor nodes, a sensing subsystem, a deciding subsystem, an effecting subsystem, and a power harvesting system is described. The sensing subsystem can identify pathogenic entities, including disease associated cells (for example, cancer cells, autoimmune cells, or pathological microbes) or viruses. The sensing subsystem can include at least one pad constructed of an electrically conductive material and linkers attached to the at least one pad. Each linker can also be attached to a targeting agent (for example, an antibody fragment) or a reference agent. Upon the binding of a targeting agent with an entity of interest, the information is transferred to the logic circuitry, which processes the binding event information and decides whether the entity is disease associated (e.g., a disease associated cell or virus) and requires delivery of therapeutic agents or other treatment.

Gas detector

A gas detector includes a measurement control section that controls a voltage application section, obtains an output current flowing between a first electrode and a second electrode of an electrochemical cell, and detects a concentration of sulfur oxides in exhaust gas based on the output current. The measurement control section uses a minimum value of the output current obtained by using a current detection section in a period in which lowering sweep is executed and in which an applied voltage is a voltage within a detection voltage range that is equal to or lower than a decomposition initiation voltage of sulfur oxides as a parameter used for detection of the concentration of sulfur oxides.

Apparatus and associated methods for analyte detection

An apparatus comprising first and second electrodes (201, 202) separated by an electrolyte (203), the first and second electrodes (201, 202) configured to exhibit a potential difference therebetween on interaction of the first electrode (201) with an analyte, wherein the first electrode (201) is configured such that its electrical conductance and electrochemical potential are dependent upon the amount of analyte present, the electrical conductance and electrochemical potential of the first electrode (201) affecting the potential difference between the first and second electrodes (201, 202), and wherein the apparatus comprises respective first and second terminals (204, 205) configured for electrical connection to a readout circuit to enable determination of the presence and/or amount of analyte based on the potential difference.

Oxidizing gas detection method and apparatus thereof

An oxidizing gas detection method and an apparatus thereof are provided for trace oxidizing gas detection. The detection method includes the following steps. First, perform an electroreduction reaction and a photoreduction reaction simultaneously to a metal oxide in which nanoconductors are distributed. Next, stop the electroreduction reaction and the photoreduction reaction, and read a resistance of the reduced metal oxide by applying a first pulse-width modulation signal. Next, provide an oxidizing gas to the reduced metal oxide, and photo-catalyze a redox reaction between the oxidizing gas and the reduced metal oxide. Next, read a resistance of the oxidized metal oxide by applying a second pulse-width modulation signal. Next, converse a concentration of the oxidizing gas according to a ratio of the resistance of the oxidized metal oxide and the resistance of the reduced metal oxide.