Gas analysis mass spectrometer

Physical State Evolved Gas Analysis Mass spectrometer Gas chromatography IR transmission Film sensors External sample analysis... 

The sample of a gas analysis mass spectrometer usually passes through an enclosed electron ionization... 

The high temperatures in the MHD combustion system mean that no complex organic compounds should be present in the combustion products. Gas chromatograph/mass spectrometer analysis of radiant furnace slag and ESP/baghouse composite, down to the part per biUion level, confirms this behef (53). With respect to inorganic priority pollutants, except for mercury, concentrations in MHD-derived fly-ash are expected to be lower than from conventional coal-fired plants. More complete discussion of this topic can be found in References 53 and 63. 

Factors may be classified as quantitative when they take particular values, e.g. concentration or temperature, or qualitative when their presence or absence is of interest. As mentioned previously, for an LC-MS experiment the factors could include the composition of the mobile phase employed, its pH and flow rate [3], the nature and concentration of any mobile-phase additive, e.g. buffer or ion-pair reagent, the make-up of the solution in which the sample is injected [4], the ionization technique, spray voltage for electrospray, nebulizer temperature for APCI, nebulizing gas pressure, mass spectrometer source temperature, cone voltage in the mass spectrometer source, and the nature and pressure of gas in the collision cell if MS-MS is employed. For quantification, the assessment of results is likely to be on the basis of the selectivity and sensitivity of the analysis, i.e. the chromatographic separation and the maximum production of molecular species or product ions if MS-MS is employed. 

Mass-spectral (MS) Analysis. Mass spectral analyses were obtained using a computerized Finnigan Model 1015 gas chromatograph-mass spectrometer (GC-MS) operated at 70 eV. Samples were introduced via direct insertion probe or by utilizing the GC-MS combination, both operated over a programmed temperature range. 

Lao, R. C., R. S. Thomas, H. Oja, and L. Dubois. Application of a gas chromatograph-mass spectrometer-data processor combination to the analysis of the polycyclic aromatic hydrocarbon content of urbome pollutants. Anal. Chem. 45 908-915, 1973. 

Analysis of the Mixture of Organic Compounds from the Soil. The crude fractions were analyzed using a LKB-2091 capillary gas chromatograph/mass spectrometer/data analysis system (CGC/MS/DA). The capillary column used was a J W DB-1, 60 m x 0.32 mm, connected directly to Ae ion source of the mass spectrometer. Up to 1.0 tfL of a solution of the sample in an appropriate solvent was injected directly onto the column at 40 °C, whereupon the column temperature was immediately raised to 100 for 4 min, and programmed to 310 °C at a rate of 10°/min. and held there for 30 min. 

S. Gas source mass spectrometry (GSMS) with electron impact (El) ion source produces nearly mono-energetic ions (similar to TIMS) and is an excellent tool for the high precision isotope analysis of light elements such as H, C, N and O, but also for S or Si.7,100,101 Precise and accurate measurements of isotope ratios have been carried out by gas source mass spectrometers with multiple ion collectors by a sample/standard comparison and the 8 values of isotope ratios were determined (see Equation 8.4). Electron impact ionization combined with mass spectrometry has been applied for elements which readily form gaseous compounds (e.g., C02 or S02) for the isotope analysis of carbon and sulfur, respectively). 

Mass spectrometers are used not only to detect the masses of proteins and peptides, but also to identify the proteins, to compare patterns of proteins and peptides, and to scan tissue sections for specific masses. MS is able to do this by giving the mass-to-charge ratio of an ionized species as well as its relative abundance. For biological sample analysis, mass spectrometers are connected to an ionizing source, which is usually matrix-assisted laser desorption ionization (MALDI) [14], surface-enhanced laser desorption/ioni-zation (SELDI, a modified form of MALDI) [15], or electrospray ionization [16]. These interfaces enable the transfer of the peptides or proteins from the solid or liquid phase, respectively, to the gas (vacuum) phase inside the mass spectrometer. Both MALDI and electrospray ionization can be connected to different types of mass analyzers, such as quadrupole, quadruple-ion-traps, time of flight (TOF), or hybrid instruments such as quadrupole-TOF or Fourier transform-ion cyclotron resonance. Each of these instruments can... 

Benjamin Tan, L.L., Mustafa, A.M., 2003. Analysis of selected pesticides and alkylphenols in human cord blood by gas chromatograph-mass spectrometer. Talanta 61, 385-391. 

Chemical Weapons Convention Chemicals Analysis discusses sample collection, sample preparation and analysis, and concentrates on verification that takes place on site, analyses off site, and methods and procedures used. In the first part of the book is discussed the mobile laboratory of the OPCW and instrumentation and software used therein, as well as other on-site analysis equipment, procedures, and strategies. The OPCW gas chromatograph-mass spectrometer for on-site analysis is described and... 

The OPCW Gas Chromatograph/Mass Spectrometer for On-site Analysis. Instrumentation, AMDIS Software and Preparations for Use... 

THE OPCW GAS CHROMATOGRAPH-MASS SPECTROMETER FOR ON-SITE ANALYSIS... 

Perez-Coello, M. S., Sanz, J., Cabezudo, M. D. (1998). Gas chromatographic-mass spectromet-ric analysis of volatile compounds in oak wood used for ageing of wines and spirits. Chro-matographia, 47, 427 32. 

Analysis All analyses were performed on a Hewlett-Packard 5985 B quadrupole gas chomatograph mass spectrometer. Plasma glucose was initially separated using the technique described above and the penta-acetate derivative of glucose was formed by adding acetic anhydride and pyridine to the dried glucose sample and heating at 100 C for five minutes. Approximately lul of the acetic anhydride solution was required for analysis. 

GC-MS Analysis and Identification. A portion of the acidic fractions were quantitatively converted to methyl esters using a BF3-methanol reagent. The procedure used was that of Metcalfe and Schmitz (8). The esterified acidic fractions were analyzed using a coupled gas chromatograph-mass spectrometer (GC-MS) system consisting of a Varian Moduline 2700 gas chromatograph equipped with a flame ionization detector interfaced by a jet separator to a Du Pont Instruments Model 21-490 mass spectrometer. A 10 ft x 1/8 in o d stainless steel column packed with 10% stabilized DEGS on 80/ 100 mesh Chromosorb W AW DWCS was used. The He flow rate was 30 ml/min. The column temperature was held 5 minutes at 30°C, then... 

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