Atmospheric analysis, infrared

Astronomical Observatory, were used to carry out the calculations of theoretical equivalent widths of lines, synthetic spectra and a set of plane parallel, line-blanketed, flux constant LTE model atmospheres. The effective temperatures of the stars were determined from photometry, the infrared flux method and corrected, if needed, in order to achieve the LTE excitation balance in the iron abundance results. The gravities were found by forcing Fe I and Fe II to yield the same iron abundances. The microturbulent velocities were determined by forcing Fe I line abundances to be independent of the equivalent width. For more details on the method of analysis and atomic data see Tautvaisiene et al. (2001). 

DGE a AC AMS APCI API AP-MALDI APPI ASAP BIRD c CAD CE CF CF-FAB Cl CID cw CZE Da DAPCI DART DC DE DESI DIOS DTIMS EC ECD El ELDI EM ESI ETD eV f FAB FAIMS FD FI FT FTICR two-dimensional gel electrophoresis atto, 10 18 alternating current accelerator mass spectrometry atmospheric pressure chemical ionization atmospheric pressure ionization atmospheric pressure matrix-assisted laser desorption/ionization atmospheric pressure photoionization atmospheric-pressure solids analysis probe blackbody infrared radiative dissociation centi, 10-2 collision-activated dissociation capillary electrophoresis continuous flow continuous flow fast atom bombardment chemical ionization collision-induced dissociation continuous wave capillary zone electrophoresis dalton desorption atmospheric pressure chemical ionization direct analysis in real time direct current delayed extraction desorption electrospray ionization desorption/ionization on silicon drift tube ion mobility spectrometry electrochromatography electron capture dissociation electron ionization electrospray-assisted laser desorption/ionization electron multiplier electrospray ionization electron transfer dissociation electron volt femto, 1CT15 fast atom bombardment field asymmetric waveform ion mobility spectrometry field desorption field ionization Fourier transform Fourier transform ion cyclotron resonance... 

Zwart et al. (1990) exposed groups of five male and five female Wistar rats to phosgene at varying concentrations for 5, 10, 30, or 60 min. The test atmosphere was monitored at both the inlet and outlet of the glass exposure chambers by gas chromatography and infrared analysis. The 10-min LC50 value was 80 ppm, and the 30-and 60-min LC50 values were 20 and 12 ppm, respectively. 

Fourier Transform Infrared Analysis of Trace Gases in the Atmosphere... 

Griffith, D. W. T., and G. Schuster, Atmospheric Trace Gas Analysis Using Matrix Isolation-Fourier Transform Infrared Spectroscopy, J. Atmos. Chem., 5, 59-81 (1987). 

Carbonylchlorocopper(I) is a colorless crystalline substance that decomposes rapidly in the absence of a carbon monoxide atmosphere to give copper(I) chloride and carbon monoxide. The compound is, however, stable for long periods of time if stored under carbon monoxide. Cu(CO)Cl has a polymeric structure,10 which may be described as layers of fused, six-membered, copper-chloride rings in the chair conformation, with terminally bonded carbonyl ligands. The infrared spectrum of Cu(CO)Cl (Nujol mull at 0°C) displays a characteristic large peak at 2127 cm -1 and a vibrational analysis has been reported.13... 

Reaction of PCTFE with a stoichiometric amount of chromium hexacarbonyl in DMF at 95°C for 5 days under a nitrogen atmosphere, followed by hydrolysis results in the formation of a brown-black polymer. Analysis of the infrared data indicates that carbonylation does indeed occur (Equation 11). The infrared absorption spectrum shows a large decrease in the C-Cl stretch at 970 cm-1 with a concomitant appearance of a very strong band in the carbonyl stretching region centered at 1680 cm1. There is also a broad band centered at 3490 cm-1 in the hydroxyl stretching region and two bands of moderate intensity... 

Present theoretical efforts that are directed toward a more complete and realistic analysis of the transport equations governing atmospheric relaxation and the propagation of artificial disturbances require detailed information of thermal opacities and long-wave infrared (LWIR) absorption in regions of temperature and pressure where molecular effects are important.2 3 Although various experimental techniques have been employed for both atomic and molecular systems, theoretical studies have been largely confined to an analysis of the properties (bound-bound, bound-free, and free-free) of atomic systems.4,5 This is mostly a consequence of the unavailability of reliable wave functions for diatomic molecular systems, and particularly for excited states or states of open-shell structures. More recently,6 9 reliable theoretical procedures have been prescribed for such systems that have resulted in the development of practical computational programs. 

The isourea protocol was carried out in a 9 1 dichloromethane/N,N-dimethylf-ormamide (DCM/DMF) solvent mixture in sealed vessels, whereas the anhydride reactions were carried out in 1 -methyl-2-pyrrolidinone (NMP) under atmospheric pressure. In all experiments, the loading was estimated by on-bead Fourier transform infrared spectroscopy (FTIR) analysis and determined by cleavage from the PS Wang resin with 50% TFA in DCM. 

In a study conducted by the Armour Research Foundation (Ref 41) a-Pb azide crystals wrapped in a thin A1 foil were subjected to fast and thermal neutrons in the heavy water pile at Argonne National Laboratory. With a thermal flux rate of about 10l4n/cm2/sec the crystals were irradiated for 8, 17 and 170 hours. The crystals decompd to a brown powder which was identified as Pb carbonate by X-ray techniques and infrared absorption spectra. From a mass spectrographic analysis of the isotopes of carbon and oxygen in the decompn products, it was determined that the mechanism of carbonate formation is a reaction with the atmosphere by broken surface bands produced by the neutrons. Subsequently, Raney (Ref 60) reported... 

Most atmospheric visible and DV absorption and emission involves energy transitions of the outer electron shell of the atoms and molecules involved. The infrared spectrum of radiation from these atmospheric constituents is dominated by energy mechanisms associated with the vibration of molecules. The mid-infrared region is rich with molecular fundamental vibration-rotation bands. Many of the overtones of these bands occur in the near infrared. Pure rotation spectra are more often seen in the far infrared. Most polyatomic species found in the atmosphere exhibit strong vibration-rotation bands in the 1 - 25 yin region of the spectrum, which is the region of interest in this paper. The richness of the region for gas analysis... 

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