Mass radio frequency

In an inhomogeneous radio frequency (RF) field, ions can be guided from one part of a mass spectrometer to another. 

Quadrupole analyzer. A mass filter that, creates a quadrupole field with a DC component and an RF (radio frequency) component in such a manner as to allow transmission only of ions having a selected mass-to-charge (m/z) ratio. 

Spark Source Mass Spectrometry (SSMS) is a method of trace level analysis—less than 1 part per million atomic (ppma)—in which a solid material, in the form of two conducting electrodes, is vaporized and ionized by a high-voltage radio frequency spark in vacuum. The ions produced from the sample electrodes are accelerated into a mass spectrometer, separated according to their mass-to-charge ratio, and collected for qualitative identification and quantitative analysis. 

S. DeGendt, R.E. Van Grieken, S.K. Ohorodnik and W.W. Harrison, Parameter evaluation for the analysis of oxide-based samples with radio frequency glow discharge mass spectrometry, Anal. Chem., 67 (1995) 1026-1033. 

The plasma is maintained at a temperature of 10 000° C by an external radio frequency current, as described in Section 3.3. At this temperature, many molecular species are broken down, and approximately 50% of the atoms are ionized. So far this is identical to ICP-OES, but for ICP-MS we are not interested in the emission of electromagnetic radiation, but rather in the creation of positive ions. To transfer a representative sample of this plasma ion population to the mass spectrometer, there is a special interface between the plasma and the mass spectrometer. This consists of two sequential cones... 

Douglas DJ, French JB (1992) Collisional focusing effects in radio frequency quadropoles. J Am Soc Mass Spectrom 3 398-407... 

Lawson, G. Todd, J.F.J. Radio-Frequency Quadrapole Mass Spectrometers. Chem. Brit. 1972,8,373-380. 

Tolmachev, A.V. Udseth, HR. Smith, R.D. Radial Stratification of Ions As a Function of Mass to Charge Ratio in Collisional Cooling Radio Frequency Multipoles Used As Ion Guides or Ion Traps. Rapid Commun. Mass Spectrom. 2000,74, 1907-1913. 

Thomson, B.A. 1997 McBryde Medal Award Lecture Radio Frequency Quadrupole Ion Guides in Modem Mass Spectrometry. Can. J. Chem. 1998, 76, 499-505. 

The quadrupole analyzer uses oscillating electrical fields to separate ions based on their stable trajectories. The analyzer consists of four parallel poles placed between the ion source and the detector in such a manner that the path of the ion beam travels through the middle. The rods have DC voltages applied to opposite rods to carry the same charge, yielding one set of positive rods and one set of negative rods. All four rods have an oscillating radio frequency (RP) applied to them (Honour, 2003). If the ion mass is too... 

Quadrupole or radio-frequency mass analyzers have only recently become available with the mass range and resolution 42) to be of general use in inorganic and organometallie mass spectrometry, although they have been popular as small mass spectrometers built into specific systems as reaction monitors. They do have the advantage of essentially linear... 

Quadrupole ion trap, time of flight, mass spectrometer Quantum yield Research and development Reversal electron attachment detection Remote environmental monitoring units Remote explosive scent tracking Radio frequency Ragnar s Homemade Detonators Receiver operator characteristics (a graphical portrayal of Pd and Pfp)... 

A mass spectrum (positive or negative) is obtained by maintaining a fixed radio frequency (RF) field and varying the magnetic field. Ions are brought into resonance with the RF field when condition (14) is satisfied, where... 

Quadrupole mass analyzers consist of four rods that produce a radio frequency quadrupole field. Only a single mass-to-charge ratio has a stable trajectory through the mass analyzer, but the electric potentials can be swept rapidly, either continuously or in discrete steps to measure a variety of masses. Quadrupole mass spectrometers are used in a wide variety of applications, but are not widely used in cosmochemistry. 

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