Mechanical properties of β-HMX.

Background: For a full understanding of the mechanical properties of a material, it is essential to understand the defect structures and associated properties and microhardness indentation is a technique that can aid this understanding.

Results: The Vickers hardness on (010), {011} and {110} faces lay in the range of 304-363 MPa. The Knoop Hardnesses on the same faces lay in the range 314-482 MPa.

Laser applications to chemical and environmental analysis: introduction to the feature issue.

This issue of Applied Optics features 14 papers that describe recent advances of laser techniques, including instrumentation, application in combustion research, and detection of pollutants. Most of these contributions were presented at the Eighth Optical Society of America Topical Meeting on Laser Applications to Chemical and Environmental Analysis (8th LACEA), held in Boulder, Colorado, 7-10 February, 2002.