ISSN:
0049-8246
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Physics
Notes:
Methods are considered for optimizing a conventional Bragg--Brentano X-ray powder diffractometer for the identification of crystalline phases in airborne particulates deposited on membrane filters. The instrumental parameters investigated include detector stepping increment and scan range, Kβ filtration, and the incident beam divergence slit width. Sample-related factors such as substrate material (cellulose ester, polycarbonate and polytetrafluoroethylene), off-axis displacement of the sample and X-ray induced specimen degradation were also studied. Scan times for sample deposits of several hundred μcm-2 are in the vicinity of 24 h with an 800 W tube. These times may be reduced substantially by one or more of the following modifications: rotating anode or synchrotron radiation source, energy-dispersive diffractometry, and Bragg--Brentano diffractometry with a position-sensitive gas detector.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/xrs.1300090207
