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A rapid method for the determination of rubidium in cesium metal by X-ray fluorescence is described. Cesium metal is converted to the chloride, and pellets are pressed with molybdenum trioxide as an internal standard. The rubidium to molybdenum intensity ratio is used to eliminate the effect of small amounts of the other alkali metals. The analytical curve is linear from 0.05 to 15% rubidium, which covers the range of samples normally encountered. Rubidium can be determined with a coefficient of variation of 1.3% in this range. Good agreement was shown with results obtained by flame photometry.

Tantalum metal is analyzed for 12 impurity elements by using a carrier distillation technique with a dc arc. The metal is oxidized in a muffle oven at 900°C. The oxide is mixed with a special carrier made of silver metal, silver chloride, and barium fluoride. A set of standards is included on each plate, and the analytical curves are linear for the concentration range used. The coefficient of variation varies from 30 to 87%

A carrier distillation technique is described for the analysis of trace impurities in niobium oxide. The carrier used is a 1: 1 mixture of AgCl and AgF. Separation of the carrier and sample charge along with the use of a boiler cap on the electrode cup greatly reduces the background and yet allows the impurities to be distilled into the arc within 90 sec. Sensitivity and precision data are included for 13 impurity elements.

This study involves the measurement of RMS velocities covering the frequency spectrum 25 to 20,000 hertz using an electro gas dynamic (EGD) probe. Previous work proved the feasibility of this investigation. The flow of air behind a circular cylinder was measured. The freestream velocity was 185 ft/sec. Charged water droplets entering the wake through a jet in the cylinder at sonic velocity acted as the media for conveying information to the probe. Hot-wire anemometer readings made in the same spectral range were used as the standard of comparison. However, these need further refinement. Small droplet formation was optimized by determination and control of the relative humidity of the freestream, steam temperature and steam pressure. Optimum droplet charge was then determined and controlled with corona voltage. A 10 to 15 decibel increase in high frequency response and stable performance resulted. http://archive.org/details/spectralnemometr1094515909 Lieutenant, United States Navy Approved for public release; distribution is unlimited.