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 24 for “"Gas detection"”.
-
A study of a correlation spectroscopy gas detection method
The study of an optical correlation spectroscopy gas detection system is presented in this thesis. The correlation spectroscopy method uses a sample of reference gas as a filter to identify the concentration of the target gas in a measurement gas cell. containing reference gas cell was also …
-
Near-infrared tunable diode laser absorption spectrometer for trace gas detection
… analysis of the noise performance of different detection schemes has been performed. It was concluded that near optimum performance could be achieved using second harmonic wavelength modulation spectroscopy in the 50-100k Hz region. Instrument sensitivity was enhanced through the use of a …
-
Functional Materials and Device Concepts for Magnetic Sensing, Gas Detection and Energy Harvesting
… magnetic-field sensing, energy harvesting, and gas detection. Although examined separately, they are linked by their potential integration into self-sustaining sensor platforms for Internet of Things (IoT) applications, amid growing demand for sensing systems in industrial, environmental, and …
-
Highly Sensitive and Selective Gas Sensors Based on Vertically Aligned Metal Oxide Nanowire Arrays
… arrays were used as the active materials for gas detection. Metal oxide nanowire arrays share similar 3D structures as the array of mammal's olfactory receptors and the chemical reactivity of nanowire array can be modified by surface coatings. In this dissertation, two standalone gas sensors …
-
Optimization of copper oxide film by dip coating technique for oxygen detection
Copper oxide (CuO) based gas sensor has been widely investigated due to its low- cost material, nontoxicity and abundant on earth. The CuO hierarchical structure is used to enhance the sensing performance of the gas sensor. This is because of its structure provides large surface area for the …
-
MEMS-based resonant sensor arrays : selective detection of volatile and toxic chemicals
… While there are many options available for gaseous chemical detection and identification, not all are well-suited toward the creation of a portable device. Boston MicroSystems, Inc. (BMS) has developed a resonant chemical sensor that is predicted to meet the performance needs of the current …
-
Frequency Limitation for Triaxial Induction Tools and Dielectric Tools in 1-D Multi-Layered Transverse Isotropic Formation
… in distinguishing thinly laminated shale oil/gas detection. Dielectric tools have higher working frequency than triaxial induction tools. In this thesis, an analytical method is used to simulate the responses of triaxial induction tools in one-dimensional multi-layered transverse isotropic …
-
Development of BJT radiation sensors and read-out systems for Radon detection
… and optimized for alpha particle and radon detection and monitoring. Using functional tests, we have shown that BJT detector operated with floating base can efficiently be used for the purpose of alpha-particle and, consequently, radon gas detection. Basing on these results, we have designed …
-
Influencia de la posición del sensor MQ-6 y el tiempo transcurrido en la detección de concentración de GLP en una fuga doméstica
Gas leaks in Lima and Ica (Peru) increase every year, causing accidents and irreparable damage to the population. In this article, a controlled leak was produced using a two-burner kitchen and an array of MQ-6 sensors positioned at different angles (45°, 0° and 30°) with respect to the kitchen. The …
-
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, …
-
Photoacoustic photonic crystal fiber gas sensor
… that has demonstrated very high sensitivity for gas detection. Typically, PAS involves the absorption of a modulated laser beam by the gas species of interest, and the subsequent generation of acoustic waves at the modulation frequency. The amplitude of the acoustic signal, which can be measured …
-
Cryptophane Derivatives as Gas Sensors and Hyperpolarized Xenon-129 Biosensors
ABSTRACT CRYPTOPHANE DERIVATIVES AS GAS SENSORS AND HYPERPOLARIZED XENON-129 BIOSENSORS Najat S. Khan Professor Ivan J. Dmochowski This thesis describes the progress in the development of cryptophanes for three different applications: encapsulation of noble gases, 129Xe NMR biosensing for cancer …
-
CdSe based nanowires for the photocatalytic production of hydrogen gas
… achieving a decarbonized supply of hydrogen gas for clean energy conversion technologies such as the proton exchange membrane fuel cell (PEMFC). This study uses a template-directed electrodeposition technique to synthesize multi-segmented CdSe based nanowires for use as a photocatalyst device …
-
Multiphysics Coupling Analysis of Indicator Gas Variations Induced by Coal Spontaneous Combustion in Longwall Goaf
… behaviour and distribution patterns of indicator gases within longwall goaf is critical for preventing coal mine spontaneous combustion (sponcom). In prior studies, coal self-heating temperature and variations of gas products are often analysed independently, making it challenging to …
-
A fundamental study of epitaxial graphene on silicon carbide on silicon for mid-infrared nanophotonics
… for many applications such as exhaled breath detection, cancerous tissue diagnosis, water quality monitoring, greenhouse gas detection, machine vision, and navigation. Plasmonics has enabled sub-diffraction confinement and manipulation of light. However, the high losses and lack of dynamic …
-
Design and analysis of memristor-based reliable crossbar architectures
… and analysis of memristor’s application in gas sensing is presented. This proposed model captures the gas sensing properties of titanium-dioxide using gas concentration to control the overall memristance of the device. This model is used to design and simulate a first-of-its-kind sneak-paths …
-
Printable and Machine Intelligent 0D/2D Materials Gas Sensor Arrays
A smart gas sensor array (GSA) powered by machine intelligence is a machine-equivalent olfactory system of mammalian nose. Such systems’ ability to distinguish different species of gases and quantitatively measure trace-level gas concentrations is crucial for pollution monitoring, hazard gas …
-
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 …
Page 1 of 2