Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 107 for “"gas sensing"”.
-
Toxic Gas Sensing on Nanoporous Carbons
… layers of the carbon samples were used for the sensing of gaseous ammonia. They were exposed to continuous cycles of various ammonia concentrations (10-500 ppm), and changes in normalized resistance were analyzed. In all cases linear responses were recorded and the chips reached sensitivities as …
-
Optimization of nanostructured materials towards gas sensing
… presence. During the last decades, solid-state gas sensors have played an important role in environmental monitoring and chemical process control. The strong investigation which followed, made clear that the field of science and sensor technology cannot search for new sensor materials which are …
-
Vertical silicon nanowire arrays for gas sensing
… characterize vertically aligned silicon nanowire gas sensors. Silicon nanowires are very attractive for gas sensing applications and vertically aligned silicon nanowires are preferred over horizontal nanowires for gas sensing due to the high density of nanowire arrays and the increased nanowire …
-
Inverse techniques: problems in optics and gas sensing
… classes of problems are discussed: locating gas sources from downwind gas concentration measurements and designing diffractive optics (i.e. computer generated holograms), which on illumination will produce a desired light beam in the far field. The similarity between these problems is that …
-
Metalloporphyrin-decorated semiconducting oxides for gas sensing applications
… released the first practical semiconductor gas sensor applied to the market, more and more researchers have invested in the research on the improvement and application of semiconductor gas sensors and a large number of modified tin oxide gas sensors with various gas sensing properties have …
-
Miniature gas sensing device based on near-infrared spectroscopy
… of atoms, molecules, or ions concentrations in gaseous samples are in great demand for medical, environmental, industrial, law enforcement and national security applications. These applications require in situ, high-resolution, non-destructive, sensitive, miniature, inexpensive, rapid detection, …
-
Thermal characterisation of miniature hotplates used in gas sensing technology
… (MEMS) infra-red (IR) emitter chips for use in gas sensing technology for stable long-term operation were studied, using both IR and a novel thermo-incandescence microscopy. The IR emitters were fabricated using complementary-metal-oxide semiconductor (CMOS) based processing technology and …
-
Field-Portable dissolved gas sensing and perspectives in aqueous microplastic detection
… stimulated increased release of methane (CH4), a gas with a shorter lifetime in the atmosphere but with even more heat trapping ability than CO2. In situ analysis of dissolved gas content in surface waters is currently performed with large, expensive instruments, such as spectrometers, which are …
-
Hydrothermally grown Pb2+ doped ZnOnanorods for hydrogen and acetylene gas sensing
… deposition. These thin films were used for both gas sensing and as seed for orientated ZnO nanorods deposition. Rutherford Backscattering was used to measure the thickness and stochiometry of the deposited ZnO films. Orientated ZnO nanorods were then deposited on glass slides with ZnO thin films …
-
Heterogeneous integration of graphene and Si CMOS for gas sensing applications
Detecting presence of gas molecules is of prominent importance for controlling chemical processes, safety systems, and industrial and medical applications. Despite enormous progress in this field over past few decades on developing and improving various types of gas sensors, sensors with higher …
-
The application of quantum cascade lasers to mid-infrared gas sensing
… the development of a quantum cascade laser based gas sensor and the verification of performance of the resulting product. The capability to detect trace levels of multiple species in varying physical conditions, specifically high temperature is shown.Optical designs capable of allowing the …
-
Field-Portable Dissolved Gas Sensing and Perspectives in Aqueous Microplastic Detection
… stimulated increased release of methane (CH4), a gas with a shorter lifetime in the atmosphere but with even more heat trapping ability than CO2. In situ analysis of dissolved gas content in surface waters is currently performed with large, expensive instruments, such as spectrometers, which are …
-
Design and Evaluation of Off-centered Core Fiber for Gas Sensing
Gas Sensing Has Become a Very Important and Attractive Technique Because of Its Various Applications, Such as in the Increasingly Concerning Case of Environmental Issues, Automobile Emission Detection, Natural Gas Leakage Detection, Etc. It Also Has Significant Applications in Industries, Such as …
-
Synthesis and characterisation of DLC and diamond films for gas sensing applications
… rate, argon, nitrogen as well as oxygen gas flow rate. The as-deposited thin films were characterized using several characterization techniques. The roughness of the sample was studied using atomic force microscopy (AFM) and it was estimated to be 0.292- 3.2 nm. Scanning Electron …
-
Optical characterisation of quantum well infrared photodetectors (QWIPs) for gas sensing applications
Although much work has been done on λ∼5-12 μm quantum well infrared photodetectors (QvWPs), the distinctive feature of this project is the use of strain compensated materials on InP substrates, AIAs (tensile) and InGaAs (compressive), to achieve shorter wavelengths and higher temperature operation. …
-
Thulium-doped fibre laser in the 2 μm wavelength region for gas sensing
… be very useful as spectroscopic tools for trace gas detection. Semiconductor lasers are often not readily available at a reasonable cost with the specific wavelengths required to provide a close ‘match’ to the key absorption features of the gases of interest. Well-designed fibre laser-based …
-
Palladium (pd) decorated zinc oxide (ZnO) nanoparticles for gas sensing applications: meat spoilage gases
… method for the purpose of testing their gas sensing properties. After the synthesis of these nanoparticles, various characterization techniques for the investigation of both physical and chemical properties were employed. Different percentages of Palladium ranging between 0.2% and 0.7% …
-
Synthesis and characterization of tungsten oxide wo3 nanostructures thin films for gas sensing applications
… presents the synthesis of a room temperature gas sensor based on tungsten oxide (WO3) thin films. The synthesis of WO3 thin films was carried out using a direct current (DC) reactive magnetron sputtering at different deposition temperatures (300, 400 and 500 ºC). The deposition time, pressure, …
-
Growth and characterization of FeSi nanowires by chemical vapor deposition for gas sensing applications
FeSi nanowires were synthesized via a chemical vapor deposition method. Anhydrous FeCl3 powder in this case served as the Fe source and was evaporated at a temperature of 1100oC to interact with silicon substrates which served as the silicon source. The nanowires followed the vapor solid (VS) …
Page 1 of 6