The electrical resistivity and specific heat of samples of 241Am and 243Am are reported. The electrical resistivity at room temperature is reduced compared with the value for plutonium, while the power law exponent at low temperatures is increased. The electronic specific heat coefficient is lower than for the lighter actinides. These features lead to the conclusion that americium is the first of the actinides in which the 5 f electrons are essentially localized. Anomalies occur in the electrical resistivity and in the specific heat in the region of 60 K, the cause of which is unknown.

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Lifetime and reliability of high-power diode laser bars are sensitively related to operating temperature, mounting stress, and solder electromigration. These three factors have been taken into account for the development of a new packaging technology for 1-cm laser bars of gallium arsenide. We examinae the use of chemical-vapor-deposited (CVD) diamond as heatspreaders in order to reduce thermal resistance of a microchannel cooler for liquid cooling. We show that it is possible to perform hard soldering on a CVD-diamond with a new technique. Additionally, we present a controlled water cooling system fit to the flow characteristics of the cooler. It permits one to adjust the emission wavelength of the diode lasers by changing the water flux

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