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Variable Pressure Mode

Mode that allows some SEMs to operate at varying chamber pressures. DiscussionThe need for application of a conduc- tive coating is minimized when using variable pressure mode; however, EDS can be complicated because of the electron beam spread experienced at higher operating pressures.

Committee

Trace Materials

Date Added to Lexicon

06/12/2023

Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)

ANSI/ASTM E2809-22 Standard Guide for Using Scanning Electron Microscopy/Energy Dispersive X-Ray Spectroscopy (SEM/EDS) in Forensic Polymer Examinations. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2022. Source link

Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, https://www.astm.org