Sökning: "gas absorption"

Visar resultat 1 - 5 av 257 avhandlingar innehållade orden gas absorption.

  1. 1. Factors Related to the Formation of Gas Porosity in Grey Cast Iron: Investigation of Core Gas Evolution and Gas Concentrations in Molten Iron

    Författare :Jessica Orlenius; Chalmers University of Technology; []
    Nyckelord :core binders; Gas porosity; hydrogen; grey iron; gas absorption; nitrogen; oxygen; gas evolution rate; green sand; mould filling; gas volume; gas solubility;

    Sammanfattning : Since gas porosity is a major casting problem, it is of greatest importance to increase the knowledge about the foundry process in order to minimise the presence of gas porosity and thereby improving the casting quality. Gas porosity is generally considered to originate from gases precipitated during solidification of iron and from entrained gas picked up by the metal during the mould filling. LÄS MER

  2. 2. Mid-infrared photonic devices for on-chip optical gas sensing

    Författare :Floria Ottonello Briano; Kristinn B. Gylfason; Delphine Marris-Morini; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; mid-infrared; mid-IR; photonics; silicon photonics; gas sensing; optical sensing; optical gas sensing; spectroscopy; absorption; dispersion; carbon dioxide; CO2; CO2 sensing; trace gas; ethanol sensing; alcohol sensing; waveguide; photonic waveguide; ring resonator; nanowire; nanoheater; emitter; thermal source; bolometer; microbolometer; thermal detector; high frequency; 3 omega method; plasmonic; platinum; Kanthal; silicon-on-insulator; micro-electro-mechanical systems MEMS ; microfabrication; microsystems; microtechnology; nanotechnology; Optics and Photonics; Optik och fotonik; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Gas detection is crucial in a wide range of fields and applications, such as safety and process control in the industry, atmospheric sciences, and breath diagnostics. Optical gas sensing offers some key advantages, compared to other sensing methods such as electrochemical and semiconductor sensing: high specificity, fast response, and minimal drift. LÄS MER

  3. 3. Laser Absorption Spectroscopy of Gas in Scattering Media

    Författare :Märta Lewander; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; medical diagnosis; gas analysis; absorption spectroscopy; diode laser spectroscopy; light scattering; food-package monitoring; GASMAS;

    Sammanfattning : Absorption spectroscopy constitutes a chemical analysis tool which can be applied to various samples and application fields. This thesis focuses on gas absorption spectroscopy with the means of diode lasers - tunable diode laser absorption spectroscopy, TDLAS. LÄS MER

  4. 4. Light Propagation and Gas Absorption Studies in Turbid Media Using Tunable Diode Llaser Techniques

    Författare :Liang Mei; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gas in scattering media absorption spectroscopy; tunable diode laser absorption spectroscopy; frequency modulated light scattering interferometry; light propagation; Absorption spectroscopy; turbid media; diode laser; gas monitoring; porous media; ceramics; food packaging; Fysicumarkivet A:2014:Mei;

    Sammanfattning : Optical absorption spectroscopy is a widely used analytical tool for constituent analysis in many applications. According to the Beer-Lambert law, the transmitted light intensity through a homogeneous medium is an exponential function of the product of the concentration, the total pathlength, and the absorption cross-section of the absorbing substance. LÄS MER

  5. 5. Real-time breath gas analysis of carbon monoxide : laser-based detection and pulmonary gas exchange modeling

    Författare :Ramin Ghorbani; Florian M. Schmidt; Anders Blomberg; Christoffer Boman; Staffan Schedin; Jonathan Beauchamp; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; MEDICAL AND HEALTH SCIENCES; carbon monoxide CO ; pulmonary gas exchange; computational modeling; real-time breath gas analysis; single-exhalation profile; laser absorption spectroscopy; nonlinear least-squares fitting; breath sampling; baseline level; diurnal variation; healthy population; exposure study; fysik; Physics; Physiology; fysiologi;

    Sammanfattning : Breath gas analysis is a promising approach for non-invasive medical diagnostics and physiological monitoring. Real-time, breath-cycle resolved biomarker detection facilitates data interpretation and has the potential to improve the diagnostic value of breath tests as exhalation profiles carry spatiotemporal information about biomarker origin and gas exchange in the respiratory tract. LÄS MER