In this paper, we present an approach to develop an optical gas leak sensor that can be used to measure ethylene, dimethyl ether, and methane. The sensor is designed based on the principles of IR absorption spectrum detection, and comprises two crossed elliptical surfaces with a folded reflection-type optical path. We first analyze the optical path and the use of this structure to design a mini...

We present a gas sensitive thin-film transistor (TFT) based on an amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) semiconductor as the sensing layer, which is fabricated on a free-standing flexible polyimide foil. The photo-induced sensor response to NO₂ gas at room temperature and the cross-sensitivity to humidity are investigated. We combine the advantages of a transistor based sensor with flexi...

A new approach to intelligent gas sensor (IGS) design using a classifier based on adaptive resonance theory (ART) artificial neural network (ANN) is presented. Using published data of sensor arrays fabricated and characterised at our laboratory, we demonstrate excellent gas/odour identification performance of our classifier for a 4-gas, 4-sensor system to identify individual gas/odour. Since th...

Porous TiO2 films were prepared by the micro-arc oxidation (MAO) of Ti plates, and their CO sensing properties at low concentrations (5–100 ppm) were investigated as an application for an air quality control sensor. The obtained rutile films exhibited the maximum CO gas response at 350 ◦C, which is typical for semiconductor-type gas sensors, and the Ra/Rg was ∼1.6 for 10 ppm CO (Ra: resistance ...

Wireless telemetry systems are now becoming a relevant topic in the field of critical process control in industrial plants and oil/gas refineries. In contrast to wire line communication, wireless links are inherently unreliable. This unreliability depends critically on the propagation environment of the radio-links as the layout of scattering objects (pipes and metallic structures) influences t...

ZnO and ZnO: Mn nanocrystals were synthesized via reverse micelle method. The structural properties of nanocrystals were investigated by XRD. The XRD results indicated that the synthesized nanocrystals had a pure wurtzite (hexagonal phase) structure. Resistive gas sensors were fabricated by providing ohmic contacts on the tablet obtained from compressed nanocrystals powder and the installation ...

We prepared 0.1 wt%-30 wt% Pd-loaded Co3O4 by a colloidal mixing method and investigated the sensing properties of a Pd-loaded Co3O4 sensor element, such as the sensor response, 90% response time, 90% recovery time, and signal-to-noise (S/N) ratio, toward low nitric oxide (NO) gas levels in the range from 50 to 200 parts per billion. The structural properties of the Pd-loaded Co3O4 powder were ...

ZnO and ZnO: Mn nanocrystals were synthesized via reverse micelle method. The structural properties of nanocrystals were investigated by XRD. The XRD results indicated that the synthesized nanocrystals had a pure wurtzite (hexagonal phase) structure. Resistive gas sensors were fabricated by providing ohmic contacts on the tablet obtained from compressed nanocrystals powder and the installation ...

Flotation process in mechanical cells is carried out in highly turbulent conditions. In this work, the impact of impeller speed on four characteristics of the quiescent zone, i.e. zone height, turbulence, solid percentage, and gas holdup, and their relationship with the entrainment is investigated, and it is shown why at a higher impeller speed, entrainment is not significant. The height of the...

Here, a silicon nanopillar array (Si-NPA) was fabricated. It was studied as a room-temperature organic vapour sensor, and the ethanol and acetone gas sensing properties were detected with I-V curves. I-V curves show that these Si-NPA gas sensors are sensitive to ethanol and acetone organic vapours. The turn-on threshold voltage is about 0.5 V and the operating voltage is 3 V. With 1% ethanol ga...