English  |  正體中文  |  简体中文  |  Items with full text/Total items : 50123/85142 (59%)
Visitors : 7904220      Online Users : 50
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version
    Please use this identifier to cite or link to this item: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/25733


    Title: Effects of collisional coolling on ion detection in a quadrupole ion trap mass spectrometer
    Authors: 吳慧芬;Wu, Hui-Fen;Brodbelt, Jennifer S.
    Contributors: 淡江大學化學學系
    Keywords: collisional cooling;collision-activated dissociation;ion detection
    Date: 1992-05
    Issue Date: 2009-12-01 09:13:38 (UTC+8)
    Abstract: The effects of collisional cooling on the storage and detection of ions in a quadrupole ion trap mass spectrometer are examined. Four parameters that affect the storage of ions are evaluated: the pressure of the buffer gas: the qz value which establishes the ion trapping environment; the cooling time during which ions may collapse to the center of the trap; and the supplementary a.c. voltage used to kinetically excite selected ions. The ion trap may be operated effectively at a low helium pressure (0.1 mTorr) if a sufficient delay period is added to allow the diffuse ion cloud to collapse to the center of the trap prior to detection. For a typical experiment, this modified operation at low pressures involves allowing the ions to undergo approximately 30–100 collisions (i.e. in a ≈30 ms interval at 0.1 mTorr). At low helium pressures (≈0.1 mTorr), more ions may be trapped at higher qz values. Collision-activated dissociation (CAD) at low helium pressures indicates that the average internal energy deposition is higher, and sensitivity is not lost, if a collisional cooling delay is added. This latter result potentially has great analytical relevance for CAD of biomolecules which require greater internal energy deposition to induce fragmentation.
    Relation: Proceedings of the 40th ASMS Conference on Mass Spectrometry and Allied Topics, pp.1757-1758
    Appears in Collections:[化學學系暨研究所] 會議論文

    Files in This Item:

    There are no files associated with this item.

    All items in 機構典藏 are protected by copyright, with all rights reserved.


    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - Feedback