The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Luyi Ding - One of the best experts on this subject based on the ideXlab platform.
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atmospheric pressure Ion trapping in a tandem faims faims coupled to a tofms studies with electrospray generated gramicidin s Ions
Journal of the American Society for Mass Spectrometry, 2001Co-Authors: Roger Guevremont, Luyi Ding, Barbara Ells, David Barnett, Randy W PurvesAbstract:A tandem FAIMS-FAIMS system for Ion trapping at room temperature and atmospheric pressure is described. The first FAIMS device consisted of a side-to-side configuratIon (sFAIMS) suitable for Ion separatIon, whereas the second FAIMS device was appropriate for Ion trapping (tFAIMS). Ions pre-selected by the sFAIMS entered the tFAIMS and were captured by virtual trapping fields at the hemispherical tip of the inner electrode. The use of the sFAIMS, with wider electrode diameters, and consequently better Ion separatIon efficiency than the tFAIMS, lowered the number of background Ions captured in the trapping regIon of tFAIMS, and thus reduced the space charge effects in the trap. This tandem device was coupled to a laboratory built time-of-flight mass spectrometer and was evaluated using the electrospray generated [M + 2H]2+ Ion of gramicidin S. The half-time (t1/2) of the exponential decay of the Ion cloud in tFAIMS, determined by monitoring the residual intensity of Ions extracted from the Ion trapping regIon of tFAIMS after various delay times, was about 2 s.
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Ion trapping at atmospheric pressure 760 torr and room temperature with a high field asymmetric waveform Ion mobility spectrometer
International Journal of Mass Spectrometry, 1999Co-Authors: Roger Guevremont, David Barnett, Randy W Purves, Luyi DingAbstract:Abstract A method for the confinement of Ions at 760 Torr and room temperature is described. We have recently shown that a cylindrical-geometry high-field asymmetric waveform Ion mobility spectrometer (FAIMS), which utilizes an Ion separatIon technique based on the change in Ion mobility at high electric fields, focuses Ions in two dimensIons. This article describes a FAIMS device in which the focusing is extended to three dimensIons (i.e. Ion trap). CharacterizatIon of the Ion trap was carried out using a laboratory-constructed time-of-flight mass spectrometer. The half-life of a m/z 380 Ion in the trap was determined to be 5 ms.
Roger Guevremont - One of the best experts on this subject based on the ideXlab platform.
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atmospheric pressure Ion trapping in a tandem faims faims coupled to a tofms studies with electrospray generated gramicidin s Ions
Journal of the American Society for Mass Spectrometry, 2001Co-Authors: Roger Guevremont, Luyi Ding, Barbara Ells, David Barnett, Randy W PurvesAbstract:A tandem FAIMS-FAIMS system for Ion trapping at room temperature and atmospheric pressure is described. The first FAIMS device consisted of a side-to-side configuratIon (sFAIMS) suitable for Ion separatIon, whereas the second FAIMS device was appropriate for Ion trapping (tFAIMS). Ions pre-selected by the sFAIMS entered the tFAIMS and were captured by virtual trapping fields at the hemispherical tip of the inner electrode. The use of the sFAIMS, with wider electrode diameters, and consequently better Ion separatIon efficiency than the tFAIMS, lowered the number of background Ions captured in the trapping regIon of tFAIMS, and thus reduced the space charge effects in the trap. This tandem device was coupled to a laboratory built time-of-flight mass spectrometer and was evaluated using the electrospray generated [M + 2H]2+ Ion of gramicidin S. The half-time (t1/2) of the exponential decay of the Ion cloud in tFAIMS, determined by monitoring the residual intensity of Ions extracted from the Ion trapping regIon of tFAIMS after various delay times, was about 2 s.
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Ion trapping at atmospheric pressure 760 torr and room temperature with a high field asymmetric waveform Ion mobility spectrometer
International Journal of Mass Spectrometry, 1999Co-Authors: Roger Guevremont, David Barnett, Randy W Purves, Luyi DingAbstract:Abstract A method for the confinement of Ions at 760 Torr and room temperature is described. We have recently shown that a cylindrical-geometry high-field asymmetric waveform Ion mobility spectrometer (FAIMS), which utilizes an Ion separatIon technique based on the change in Ion mobility at high electric fields, focuses Ions in two dimensIons. This article describes a FAIMS device in which the focusing is extended to three dimensIons (i.e. Ion trap). CharacterizatIon of the Ion trap was carried out using a laboratory-constructed time-of-flight mass spectrometer. The half-life of a m/z 380 Ion in the trap was determined to be 5 ms.
Randy W Purves - One of the best experts on this subject based on the ideXlab platform.
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atmospheric pressure Ion trapping in a tandem faims faims coupled to a tofms studies with electrospray generated gramicidin s Ions
Journal of the American Society for Mass Spectrometry, 2001Co-Authors: Roger Guevremont, Luyi Ding, Barbara Ells, David Barnett, Randy W PurvesAbstract:A tandem FAIMS-FAIMS system for Ion trapping at room temperature and atmospheric pressure is described. The first FAIMS device consisted of a side-to-side configuratIon (sFAIMS) suitable for Ion separatIon, whereas the second FAIMS device was appropriate for Ion trapping (tFAIMS). Ions pre-selected by the sFAIMS entered the tFAIMS and were captured by virtual trapping fields at the hemispherical tip of the inner electrode. The use of the sFAIMS, with wider electrode diameters, and consequently better Ion separatIon efficiency than the tFAIMS, lowered the number of background Ions captured in the trapping regIon of tFAIMS, and thus reduced the space charge effects in the trap. This tandem device was coupled to a laboratory built time-of-flight mass spectrometer and was evaluated using the electrospray generated [M + 2H]2+ Ion of gramicidin S. The half-time (t1/2) of the exponential decay of the Ion cloud in tFAIMS, determined by monitoring the residual intensity of Ions extracted from the Ion trapping regIon of tFAIMS after various delay times, was about 2 s.
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Ion trapping at atmospheric pressure 760 torr and room temperature with a high field asymmetric waveform Ion mobility spectrometer
International Journal of Mass Spectrometry, 1999Co-Authors: Roger Guevremont, David Barnett, Randy W Purves, Luyi DingAbstract:Abstract A method for the confinement of Ions at 760 Torr and room temperature is described. We have recently shown that a cylindrical-geometry high-field asymmetric waveform Ion mobility spectrometer (FAIMS), which utilizes an Ion separatIon technique based on the change in Ion mobility at high electric fields, focuses Ions in two dimensIons. This article describes a FAIMS device in which the focusing is extended to three dimensIons (i.e. Ion trap). CharacterizatIon of the Ion trap was carried out using a laboratory-constructed time-of-flight mass spectrometer. The half-life of a m/z 380 Ion in the trap was determined to be 5 ms.
David Barnett - One of the best experts on this subject based on the ideXlab platform.
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atmospheric pressure Ion trapping in a tandem faims faims coupled to a tofms studies with electrospray generated gramicidin s Ions
Journal of the American Society for Mass Spectrometry, 2001Co-Authors: Roger Guevremont, Luyi Ding, Barbara Ells, David Barnett, Randy W PurvesAbstract:A tandem FAIMS-FAIMS system for Ion trapping at room temperature and atmospheric pressure is described. The first FAIMS device consisted of a side-to-side configuratIon (sFAIMS) suitable for Ion separatIon, whereas the second FAIMS device was appropriate for Ion trapping (tFAIMS). Ions pre-selected by the sFAIMS entered the tFAIMS and were captured by virtual trapping fields at the hemispherical tip of the inner electrode. The use of the sFAIMS, with wider electrode diameters, and consequently better Ion separatIon efficiency than the tFAIMS, lowered the number of background Ions captured in the trapping regIon of tFAIMS, and thus reduced the space charge effects in the trap. This tandem device was coupled to a laboratory built time-of-flight mass spectrometer and was evaluated using the electrospray generated [M + 2H]2+ Ion of gramicidin S. The half-time (t1/2) of the exponential decay of the Ion cloud in tFAIMS, determined by monitoring the residual intensity of Ions extracted from the Ion trapping regIon of tFAIMS after various delay times, was about 2 s.
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Ion trapping at atmospheric pressure 760 torr and room temperature with a high field asymmetric waveform Ion mobility spectrometer
International Journal of Mass Spectrometry, 1999Co-Authors: Roger Guevremont, David Barnett, Randy W Purves, Luyi DingAbstract:Abstract A method for the confinement of Ions at 760 Torr and room temperature is described. We have recently shown that a cylindrical-geometry high-field asymmetric waveform Ion mobility spectrometer (FAIMS), which utilizes an Ion separatIon technique based on the change in Ion mobility at high electric fields, focuses Ions in two dimensIons. This article describes a FAIMS device in which the focusing is extended to three dimensIons (i.e. Ion trap). CharacterizatIon of the Ion trap was carried out using a laboratory-constructed time-of-flight mass spectrometer. The half-life of a m/z 380 Ion in the trap was determined to be 5 ms.
Laurent Bonneviot - One of the best experts on this subject based on the ideXlab platform.
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MCM-41 "LUS": Alumina Tubular Membranes for Metal SeparatIon in Aqueous SolutIon
Journal of Physical Chemistry C, 2011Co-Authors: H. Kassab, M. Pera-titus, K. L. Yeung, Belen Albela, Laurent BonneviotAbstract:Heavy metals are discharged to the environment through industrial effluents in which certain amounts of valuable metal Ions such as gold and silver are present. Current technologies remove metal Ions nonspecifically, which constitutes a serious difficulty for metal recovery and reuse. The present article describes the synthesis of MCM-41 (LUS-type) membranes and their further surface functIonalizatIon with aminopropyl and sulfonate groups to separate valuable and/or toxic metal Ions species in aqueous medium. A feasibility test for metal-Ion separatIon is demonstrated using two model systems: (1) toxic metal removal by separating anIonic chromate from catIonic copper Ions and (2) precious metal recovery by separating gold from copper Ions. The results reveal that aminopropyl functIonalized LUS membranes might show high selectivity to Cu(II) for the Cu(II)/Au(III) system, approaching virtually infinite selectivity depending on the pH values of both the feed and stripping solutIons and the concentratIon of chloride counteranIons. We provide a critical discussIon about the relative role of catIon diffusIon and migratIon to gain insight into the metal-Ion separatIon mechanisms.
