Search for dissertations about: "GAS"

Showing result 1 - 5 of 3743 swedish dissertations containing the word GAS.

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

    Author : Jessica Orlenius; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; core binders; Gas porosity; hydrogen; grey iron; gas absorption; nitrogen; oxygen; gas evolution rate; green sand; mould filling; gas volume; gas solubility;

    Abstract : 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. READ MORE

  4. 2. Power to gas : Bridging renewable electricity to the transport sector

    Author : Farzad Mohseni; Per Alvfors; Mats Westermark; Lars Pettersson; Maria Grahn; Björn Frostell; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; transport; renewable electricity; synthetic fuels; energy; power to gas;

    Abstract : Globally, transport accounts for a significant part of the total energy utilization and is heavily dominated by fossil fuels. The main challenge is how the greenhouse gas emissions in road transport can be addressed. Moreover, the use of fossil fuels in road transport makes most countries or regions dependent on those with oil and/or gas assets. READ MORE

  5. 3. Water Curtains in Gas Storage. An Experimental Study

    Author : Carl-Olof Söder; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; analytical simulations; unlined gas storage; jointed rock; gas migration; gas containment; geo-hydrological test methods; hydromechanical breakdown;

    Abstract : Water curtains have been used for more than 20 years to prevent the escape of gas from caverns excavated in rock. Today, the use of water curtains appears to be increasing, with applications in various forms of storage caverns. READ MORE

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

    Author : Floria Ottonello Briano; Kristinn B. Gylfason; Delphine Marris-Morini; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; 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; Optik och fotonik; Optics and Photonics; Electrical Engineering; Elektro- och systemteknik;

    Abstract : 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. READ MORE

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

    Author : Ramin Ghorbani; Florian M. Schmidt; Anders Blomberg; Christoffer Boman; Staffan Schedin; Jonathan Beauchamp; Umeå universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 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;

    Abstract : 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. READ MORE