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 109 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. …
-
High throughput methods for synthesis and impedance characterisation of ABO3 gas sensing materials
… and characterisation of resistive thick-film gas sensors by use of high throughput impedance spectroscopy. Since the 1960s semiconducting resistive gas sensors are used in a wide range of applications. However, commercial systems show disadavantages which might be overcome by the use of new …
-
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 …
-
Surface chemistry of metal oxide materials: from metalorganic and organic reactions to gas sensing
… been widely used in the fields of catalysis and gas sensing fields. Due to its unique physical and chemical properties, zinc oxide (ZnO) has attracted considerable attention. It is not only used as a catalyst for various surface reactions but also as a catalytic support. Cu/ZnO is a commonly used …
Page 1 of 6