Sökning: "gas absorption"

Visar resultat 16 - 20 av 288 avhandlingar innehållade orden gas absorption.

1. 16. Interferometric observations of H -absorbing gas in active galaxies

   Författare :Ylva Pihlström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; galaxies: absorption lines; galaxies: active; galaxies: ISM; quasars: absorption lines; radio lines: galaxies;

   Sammanfattning : .... LÄS MER

3. 17. Synchrotron radiation studies of gas phase molecules : from hydrogen to DNA sugars

   Författare :Gemma Vall-llosera; Elisabeth Rachlew; Stacey Sorensen; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; KTH thesis; synchrotron radiation; gas phase; bio molecules; Atomic and molecular physics; Atom- och molekylfysik;

   Sammanfattning : This thesis summarises experimental results on the molecular spectroscopy of gas phase molecules excited by synchrotron radiation in the VUV and soft X-ray regions. We have used three different detection techniques, photon induced fluorescence spectroscopy, photoionisation mass spectroscopy and near edge X-ray absorption fine structure spectroscopy to study molecular deuterium, hydrogen sulphide, ammonia, methanol, pyridine, pyridazine, pyrimidine, pyrazine, s-triazine, and 2-deoxy-D-ribose, the last one also known as the DNA sugar. LÄS MER

4. 18. Interstellar absorption across the electromagnetic spectrum

   Författare :Achim Tappe; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interstellar medium ISM : general; supernova remnants Crab Nebula ; emission lines; — quasars: absorption lines;

   Sammanfattning : We report results of a multi-wavelength study of interstellar absorption in diffuse molecular clouds that lie in the direction of flat-spectrum quasars. Quasars as back-ground sources allow the measurement of Galactic interstellar absorption across the electromagnetic spectrum from mm to X-ray wavelengths. LÄS MER

5. 19. Experimental Studies on CO2 Capture Using Absorbent in a Polypropylene Hollow Fiber Membrane Contactor

   Författare :Yuexia Lu; Jinyue Yan; Erik Dahlquist; Umberto Desideri; Mälardalens högskola; []
   Nyckelord :CO2 capture; Simultaneous removal of CO2 and SO2; Hollow fiber membrane contactor; Membrane gas absorption; Partial wetting; Surface modification; CO2-avskiljning; samtidig avskiljning av CO2 och SO2; ihålig fiber; membran; gas absorption; vätning; ytmodifiering; Energy- and Environmental Engineering; energi- och miljöteknik;

   Sammanfattning : In recent years, membrane gas absorption technology has been considered as one of the promising alternatives to conventional techniques for CO2 capture due to its favorable mass transfer performance. As a hybrid approach of chemical absorption and membrane separation, it exhibits a number of advantages, such as operational flexibility, compact structure, high surface-area-to-volume ratio, linear scale up, modularity and predictable performance. LÄS MER

7. 20. Modelling of cathode-plasma interaction in short high-intensity electric arc : Application to Gas Tungsten Arc Welding

   Författare :Alireza Javidi Shirvan; Isabelle Choquet; Håkan Nilsson; Armelle Vardelle; Högskolan Väst; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Electric arc discharge; sheath; pre-sheath; Knudsen layer; doped refractory cathode; arc-cathode coupling; Gas Tungsten Arc simulation; OpenFOAM.; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

   Sammanfattning : In arc welding the quality of the weld is strongly influenced by the thermal history of the workpiece which is itself governed by the electric arc heat source. The models for predicting weld properties thus need a good evaluation of the distribution of the heat input from thearc to the workpiece. LÄS MER