Wir benötigen Ihre Einwilligung zur Verwendung der einzelnen Daten, damit Sie unter anderem Informationen zu Ihren Interessen einsehen können. Klicken Sie auf "OK", um Ihre Zustimmung zu erteilen.
Standard Practice for Pulse Counting System Dead Time Determination by Measuring Isotopic Ratios with SIMS
Automatische name übersetzung:
Standard Praxis für Pulse Counting-System Totzeit Bestimmung von Messisotopenverhältnisse mit SIMS
NORM herausgegeben am 1.6.2010
Bezeichnung normen: ASTM E2426-10
Anmerkung: UNGÜLTIG
Ausgabedatum normen: 1.6.2010
SKU: NS-45280
Zahl der Seiten: 3
Gewicht ca.: 9 g (0.02 Pfund)
Land: Amerikanische technische Norm
Kategorie: Technische Normen ASTM
Keywords:
dead time, isotopic ratios, pulse counting, SIMS, Isotopic analysis, Pulse testing, SIMS (secondary ion mass spectrometry), Surface analysis, ICS Number Code 71.040.50 (Physicochemical methods of analysis)
Significance and Use | ||||
Electron multipliers are commonly used in pulse-counting mode to detect ions from magnetic sector mass spectrometers. The electronics used to amplify, detect and count pulses from the electron multipliers always have a characteristic time interval after the detection of a pulse, during which no other pulses can be counted. This characteristic time interval is known as the “dead time.” The dead time has the effect of reducing the measured count rate compared with the “true” count rate. In order to measure count rates accurately over the entire dynamic range of a pulse counting detector, such as an electron multiplier, the dead time of the entire pulse counting system must be well known. Accurate count rate measurement forms the basis of isotopic ratio measurements as well as elemental abundance determinations. The procedure described herein has been successfully used to determine the dead time of counting systems on SIMS instruments. The accurate determination of the dead time by this method has been a key component of precision isotopic ratio measurements made by SIMS. |
||||
1. Scope | ||||
1.1 This practice provides the Secondary Ion Mass Spectrometry (SIMS) analyst with a method for determining the dead time of the pulse-counting detection systems on the instrument. This practice also allows the analyst to determine whether the apparent dead time is independent of count rate. 1.2 This practice is applicable to most types of mass spectrometers that have pulse-counting detectors. 1.3 This practice does not describe methods for precise or accurate isotopic ratio measurements. 1.4 This practice does not describe methods for the proper operation of pulse counting systems and detectors for mass spectrometry. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. |
||||
2. Referenced Documents | ||||
|
Historisch
1.6.2011
Historisch
1.4.2012
Historisch
1.10.2010
Historisch
1.1.2014
Historisch
1.10.2009
Historisch
1.6.2005
Bereitstellung von aktuellen Informationen über legislative Vorschriften in der Sammlung der Gesetze bis zum Jahr 1945.
Aktualisierung 2x pro Monat!
Brauchen Sie mehr Informationen? Sehen Sie sich diese Seite an.
Letzte Aktualisierung: 2024-12-22 (Zahl der Positionen: 2 217 000)
© Copyright 2024 NORMSERVIS s.r.o.