A gas-concentration detector system incorporates a temperature sensor, a humidity sensor, and a gas-concentration detector the accuracy of which deviates as a function of temperature and humidity. Contemporaneous, real-time values of temperature, humidity, and gas concentration of a gas of interest are registered and communicated to a data processing system including a computer memory and a computer processor. Value-deviation data reflective of the degree to which the accuracy of the gas-concentration sensor deviates as a function of temperature and humidity are predetermined and stored in the computer memory. Provided with real-time gas-concentration, temperature, and humidity values, the computer processor executes a value-reconciling algorithm which, based on consultation with the stored value-deviation data, calculates and outputs a refined gas-concentration value more is accurately representative of the actual gas-concentration value within the selected environment in which gas-concentration detection and reporting is desired.

A gas sensor comprising: a substrate; a grating array disposed on top of the substrate and comprising grates; and voids defined by the grates and configured to confine gas molecules for absorption of light and analysis. A method of gas sensing comprising: generating first light; converting the first light into second light using grates of a grating array; resonating the second light within the grating array; confining gas molecules in voids defined by the grates; and causing the gas molecules to absorb the second light within the voids.

Systems and methods for controlling extraction of landfill gas from a landfill via a gas extraction system are provided herein. According to some aspects of the technology, there is provided site-level control methods for globally controlling one or more wells based on one or more characteristics of aggregate landfill gas collected from a plurality of wells at a gas output. According to some aspects of the technology, there is provided well-level control methods for locally controlling a first well based on or more characteristics of landfill gas collected from the first well. According to further aspects of the technology, there is provided hybrid control methods for making adjustments to a respective well based on both site-level and well-level control methods.

There is presented an electrochemical sensor (100) for sensing an analyte in an associated volume (106), the sensor comprising a first solid element (126), a second solid element (128) being joined to the first solid element, a chamber (110) being placed at least partially between the first solid element and the second solid element, a working electrode (104) in the chamber (110), a reference electrode (108), and wherein one or more analyte permeable openings (122) connect the chamber (110) with the associated volume (106), and wherein the electrochemical sensor (100) further comprises an analyte permeable membrane (124) in said one or more analyte permeable openings, wherein the one or more analyte permeable openings are placed at least partially between the first solid element and the second solid element.

The biological information measurement system of the present invention includes a test subject-side device provided in a toilet installation room, and a server communicable with the test subject-side device, the test subject-side device includes a sulfur-containing gas sensor sensitive to sulfur-containing gas and outputting detection data, a transmitter-receiver transmitting measurement data including detection data of the sulfur-containing gas detected by the sulfur-containing gas sensor to the server, and the server includes a database in which measurement data including detection data of sulfur-containing gas detected by the sulfur-containing gas sensor is accumulated and recorded with dates and times of defecation acts by being associated with test subject identification information, and server-side data analyzer that analyzes physical condition of a test subject on the basis of a time-dependent variation tendency of the measurement data accumulated and recorded in the database.

A portable device for measuring gas in a closed space includes an air intake and exhaust unit configured to suction external air and discharge the suctioned air, a sensor unit configured to measure characteristics of the air suctioned by the air intake and exhaust unit, a communication unit configured to communicate with a host system, a power supply unit configured to supply power to the air intake and exhaust unit, the sensor unit, and the communication unit, and a control unit configured to control the air intake and exhaust unit, the sensor unit, the communication unit, and the power supply unit so that the sensor unit measures the characteristics of the air suctioned by the air intake and exhaust unit and configured to transmit measurement information to the host system through the communication unit.

A system for monitoring a petrochemical installation is disclosed. The system can include an optical imaging system comprising an array of optical detectors. The system can comprise processing electronics configured to process image data detected by the optical imaging system. The processing electronics can be configured to detect a target species based at least in part on the processed image data. The processing electronics can further be configured to, based on a detected amount of the target species, transmit an alarm notification to an external computing device over a communications network indicating that the target species has been detected at the petrochemical installation.

A method for detecting for the presence of H.sub.2S or HS.sup.− anion in a system, comprising contacting a sample from the system with a compound, or a protonate or salt thereof, having a structure represented by:

##STR00001## wherein Y represents an aromatic group or a substituted aromatic group; n is 1 or 2; R is independently H, alkyl, substituted alkyl, a polyether moiety, carboxyl, substituted carboxyl, carbamate, substituted carbonate, carbonyloxy, alkoxy, substituted alkoxy, haloalkyl, halogen, nitro, amino, amido, aryloxy, cyano, hydroxyl, or sulfonyl; R.sup.1 is H, substituted lower alkyl, lower alkyl, substituted aralkyl or aralkyl; R.sup.2 is selected from H, acyl, substituted aralkyl, aralkyl, phosphonyl, —SO.sub.2R.sup.3; —C(O)R.sup.5; —C(O)OR.sup.7 or —C(O)NR.sup.9R.sup.10; R.sup.3; R.sup.5; R.sup.7; R.sup.9 and R.sup.10 are each independently selected from H, substituted lower alkyl, lower alkyl, substituted aralkyl, aralkyl, substituted aryl or aryl.

A gas sensor having a housing with first and second chambers featuring a porous separator located there between. The first chamber of the sensor being connected to atmosphere via a gas diffusion aperture. The gas sensor having a sensing electrode disposed within the first chamber and at least a second electrode disposed within the second chamber. The sensor having an ionic liquid electrolyte disposed within the second chamber where the sensing electrode and at least second electrodes comprise platinum.

A member for a metal oxide nanofiber based gas sensor can include a metal nanoparticle catalyst and can be formed to be functionalized by binding the metal nanoparticle catalyst and an alkali or alkaline earth metal through electrospinning and heat treatment processes. The member can detect a trace amount of a gas with high selectivity and ultra-high sensitivity by uniformly binding the alkali or alkaline earth metal and the metal nanoparticle catalyst through electrospinning and high-temperature heat treatment.