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A task group of the JCPDS-International Center for Diffraction Data (ICDD) was established with the charge of investigating the use of silver behenate, CH 3 (CH 2 ) 2 oCOO-Ag, as a possible low-angle calibration standard for powder diffraction applications. Utilizing several data collection and analysis techniques, long-period spacing (JQOI) values with a range of 58.219-58.480 A were obtained. Using the same collected data and one data analysis refinement calculation method resulted in d m values with a range of 58.303-58.425 A. Data collected using a silicon internal standard and the same singular data analysis calculation method provided d^ values with a range of 58.363-58.381 A.

The Isotope Magnet Experiment (ISOMAX), a balloon-borne superconducting magnet spectrometer, was designed to measure the isotopic composition of the light isotopes (3 Z 8) of cosmic radiation up to 4 GeV nucleon À1 with a mass resolution of better than 0.25 amu by using the velocity versus rigidity technique. To achieve this stringent mass resolution, ISOMAX was composed of three major detector systems: a magnetic rigidity spectrometer with a precision drift chamber tracker in conjunction with a three-layer time-of-flight system, and two silica-aerogel Cerenkov counters for velocity determination. A special emphasis of the ISOMAX program was the accurate measurement of radioactive 10 Be with respect to its stable neighbor isotope 9 Be, which provides important constraints on the age of cosmic rays in the Galaxy. ISOMAX had its first balloon flight on 1998 August 4-5 from Lynn Lake, Manitoba, Canada. Thirteen hours of data were recorded during this flight at a residual atmosphere of less than 5 g cm À2 . The isotopic ratio at the top of the atmosphere for 10 Be/ 9 Be was measured to be 0:195 AE 0:036 (statistical) AE 0:039 (systematic) between 0.26 and 1.03 GeV nucleon À1 and 0:317 AE 0:109 (statistical) AE 0:042 (systematic) between 1.13 and 2.03 GeV nucleon À1 . This is the first measurement of its kind above 1 GeV nucleon À1 . ISOMAX results tend to be higher than predictions from current propagation models. In addition to the beryllium results, we report the isotopic ratios of neighboring lithium and boron in the energy range of the time-of-flight system (up to $1 GeV nucleon À1 ). The lithium and boron ratios agree well with existing data and model predictions at similar energies.

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