Previous aerosol studies utilizing solid-phase microextraction (SPME) predominantly focused on volatile and semivolatile compounds in the gaseous phase. Difficulties were associated with quantitative analysis of these compounds when they were associated with atmospheric particles. The present study combines SPME technology with that of carboxen packed needles (needle trap, NT) for analysis of g...

Lu Han and Muthanna H. Al-Dahhan A gaseous tracer technique and procedures were developed and implemented to measure the axial dispersion of gas phase in a slurry bubble column reactor using air-water-glass beads (100ìm). Residence time distribution curves were obtained by measuring the response of gaseous tracer pulse input. The gas phase axial dispersion coefficient, Dg, was determined from m...

In champagne tasting, gaseous CO(2) and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO(2) and ethanol was monitored through micro-gas chromatography (μGC), all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of c...

For analyzing of compositions molecular orbitals in this article in order to combination only- xylometazolin-C7 X2 (XY) and C60– xylometozolin-C65-X2 (FXY), first got energies of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) by using NBO analyze in Gaussian 03 software. Then, occupancy parameter, g...

A brief summary of R&D for two-phase emission detectors based on the extraction of ionisation electrons from condensed nonpolar dielectrics into the gas phase is presented. Preliminary results from tests of an emission detector filled with solid methane and gaseous neon are described. Possible applications of massive emission detectors are discussed. ( 1999 Elsevier Science B.V. All rights rese...

Abstract Gas to liquid (GTL) process involves heterogeneous catalytic chemical reactions that convert synthesis gas to hydrocarbons and water vapor. A three phase reactor, called Low temperature Fischer-Tropsch (LTFT) is commonly applied for GTL process. In this reactor the gaseous phase includes the synthesis gas, light hydrocarbons and water vapor, the liquid phase is a mixture of the h...

The main and upper stages of heavy lift launchers for space applications are often fuelled by cryogenic liquids. In order to enable the re-ignition of a cryogenic upper stage for orbital changes, it is crucial to study the behaviour of these fluids in microgravity. As gaseous bubbles entering the fuel lines of the engine can cause the destruction of the engine, these bubbles are a risk for the ...

ab initio and dft methods have been used to study the seven tautomeric forms of 5-methylcytosine molecule.the related tautomer in gas phase have been studied at hf/6-31g, hf/6-31g* and b3lyp/6-31g* levels oftheory. the structures,enthalpies,entropies,gibbs free energies,relative tautomerization energies of tautomersand tautomeric equilibrium constants were compared and analyzed along with full ...

For analyzing of compositions molecular orbitals in this article in order to combination only- xylometazolin-C7 X2 (XY) and C60– xylometozolin-C65-X2 (FXY), first got energies of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) by using NBO analyze in Gaussian 03 software. Then, occupancy parameter, g...