When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Chemical ionization - Wikipedia

    en.wikipedia.org/wiki/Chemical_ionization

    Chemical ionization (CI) is a soft ionization technique used in mass spectrometry. [ 1 ] [ 2 ] This was first introduced by Burnaby Munson and Frank H. Field in 1966. [ 3 ] This technique is a branch of gaseous ion-molecule chemistry. [ 2 ]

  3. Sample preparation in mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Sample_preparation_in_mass...

    [4] [5] Mass spectrometry ionization techniques requiring the sample to be in the gas phase have similar concerns. Electron ionization (EI) in mass spectrometry requires samples that are small molecules, volatile, and thermally stable, similar to that of gas chromatography. This ensures that as long as GC is performed on the sample before ...

  4. List of mass spectrometry software - Wikipedia

    en.wikipedia.org/wiki/List_of_mass_spectrometry...

    Laboratory information management software for mass spectrometry information management and data analysis. OpenChrom: Open source: Chromatography and mass spectrometry software that can be extended using plug-ins and can run on several operating systems (Microsoft Windows, Linux, Unix, Mac OS X) and processor architectures (x86, x86_64, ppc).

  5. Mass spectral interpretation - Wikipedia

    en.wikipedia.org/wiki/Mass_spectral_interpretation

    [1] [2] Mass spectra is a plot of relative abundance against mass-to-charge ratio. It is commonly used for the identification of organic compounds from electron ionization mass spectrometry. [3] [4] Organic chemists obtain mass spectra of chemical compounds as part of structure elucidation and the analysis is part of many organic chemistry ...

  6. Mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrometry

    Techniques for ionization have been key to determining what types of samples can be analyzed by mass spectrometry. Electron ionization and chemical ionization are used for gases and vapors. In chemical ionization sources, the analyte is ionized by chemical ion-molecule reactions during collisions in the source.

  7. Atmospheric-pressure chemical ionization - Wikipedia

    en.wikipedia.org/wiki/Atmospheric-pressure...

    Atmospheric pressure chemical ionization chamber cross section. Atmospheric pressure chemical ionization (APCI) is an ionization method used in mass spectrometry which utilizes gas-phase ion-molecule reactions at atmospheric pressure (10 5 Pa), [1] [2] commonly coupled with high-performance liquid chromatography (HPLC). [3]

  8. Gas chromatography–mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Gas_chromatography–mass...

    One of the main benefits of using chemical ionization is that a mass fragment closely corresponding to the molecular weight of the analyte of interest is produced. [21] In positive chemical ionization (PCI) the reagent gas interacts with the target molecule, most often with a proton exchange. This produces the species in relatively high amounts.

  9. Direct analysis in real time - Wikipedia

    en.wikipedia.org/wiki/Direct_analysis_in_real_time

    In mass spectrometry, direct analysis in real time (DART) is an ion source that produces electronically or vibronically excited-state species from gases such as helium, argon, or nitrogen that ionize atmospheric molecules or dopant molecules. The ions generated from atmospheric or dopant molecules undergo ion-molecule reactions with the sample ...