Search for dissertations about: "gas phase"

Showing result 16 - 20 of 925 swedish dissertations containing the words gas phase.

  2. 16. Monolith Reactors in Three-Phase Processes

    Author : Rolf Edvinsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; desulfurization; methanol synthesis; acetylene hydrogenation; Taylor flow; monolith reactor; three-phase; computational fluid dynamics;

    Abstract : The use of monoliths in chemical processes has been studied with the emphasis on liquid-phase hydrogenations. A monolithic catalyst consists of many narrow, parallel channels with catalytically active species either incorporated into the wall itself or into a layer of a porous oxide deposited on the wall (a washcoat). READ MORE

  4. 17. Retention time predictions in Gas Chromatography

    Author : Yasar Thewalim; Anders Colmsjö; Torgny Fornstedt; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; gas chromatography; computer simulation; two-parameter model; retention time prediction; Analytical chemistry; Analytisk kemi; Analytical Chemistry; analytisk kemi;

    Abstract : In gas chromatography, analytes are separated by differences in their partition between a mobile phase and a stationary phase. Temperature-program, column dimensions, stationary and mobile phases, and flow rate are all parameters that can affect the quality of the separation in gas chromatography. READ MORE

  5. 18. Phase transitions in high-temperature superconductors

    Author : Jack Lidmar; KTH; []
    Keywords : Superconductivity; Vortices; Phase transitions; Strongly correlated fermions; High-temperature superconductivity; Monte Carlo simulations.; TECHNOLOGY; TEKNIKVETENSKAP;

    Abstract : Thermal fluctuations and disorder strongly influence the behaviour of hightemperature superconductors. In particular the vortices play a key role in determining their properties. In this thesis the main focus lies on phase transitions, both in ultra-thin films and in three-dimensional systems, which are driven by vortex fluctuations. READ MORE

  6. 19. On Diffusion Transport Properties in Fuel Cell Gas Diffusion Layers Using the Lattice Boltzmann Method

    Author : Mayken Espinoza Andaluz; Värmeöverföring; []
    Keywords : PEFC; lattice Boltzmann method; gas diffusion layers; porosity; Gas-phase tortuosity; permeability; inertial coefficient; diffusibility; pore-scale modeling;

    Abstract : The polymer electrolyte fuel cell (PEFC) is considered as one of the most promising devices for providing efficient, clean and noiseless conversion of chemical energy to electrical energy. This device can provide electrical and thermal energy for transport, mobile and stationary applications ranging in a wide range of power requirements. READ MORE

  7. 20. Mid- and near-infrared NICE-OHMS : techniques for ultra-sensitive detection of molecules in gas phase

    Author : Thomas Hausmaninger; Ove Axner; Kyle Crabtree; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; spectrometry; NICE-OHMS; trace gas detection; acetylene; methane; isotopologues; near-infrared; mid-infrared; shot-noise; optical parametric oscillator; teknisk fysik med inriktningen mikrosystemteknik; engineering science with specialization in microsystems technology;

    Abstract : Noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is a technique for ultra-sensitive detection of molecular absorption and dispersion. For highest performance, the technique combines cavity enhancement (CE) with frequency modulation (FM); while the former increases the effective interaction length between the light and the analyte by several orders of magnitudes, the latter removes the in-coupling of 1/f noise and makes the signals background free. READ MORE