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conduction of heat on this time scale is a minor factor and the heavier tantalum atoms will conduct heat at a slower rate than carbon atoms at the same temperature. Summary and ConclusionsThe significant results with thin gold deposits on carbon support films may be summarized as follows. Crater or void dimensions in the gold layer are relatively insensitive to projectile cluster size but are directly related to the total cluster energy. This is in contrast to results obtained with pure carbon films. The presence of thin gold layers serves to reduce the energy density deposited in the supporting carbon films to the point that only with the small 25or 50-water-molecule clusters at the highest energy per constituent atom can damage be observed in the carbon layer. With the relatively nonvolatile and heavy target material tantalum, the holes and craters formed are much more sensitive to cluster size and energy in analogy to the carbon results.Crude estimates of stopping power of cluster atoms in both the gold and tantalum experiments support the conclusion that cluster atoms lose energy more rapidly than atomic projectiles would at the same energy per atom. In addition the morphology of the holes and craters formed indicates the importance of wide angle scattering processes.The magnitude of target removed to form the largest craters or hole in our experiments is on the order of 105 atoms per incident ion. These values are much larger than one would observe for the same total energy deposited by laser sputtering, isolated atomic sputtering processes, or sputtering with polyatomic ions containing up to three atoms.Acknowledgment. The help of A. P. Irsa in the performance of these bombardment experiments is gratefully acknowledged, and we thank Neal Tempel for help in film preparation and photography. This research was carried out at Brookhaven National Laboratory under contract DE-AC02-76CH00016 with the

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Static and dynamic light scattering have been measured on D20 solutions of nonionic surfactant C12E5 in the concentration range 3-300 g dm"3 at different temperatures. The results for the semidilute solutions at higher temperatures can be explained by the scaling theory for entangled solutions of flexible polymers which exhibit phase separations. Temperature dependences of the light scattering data suggest that the "0 temperature" exists at 27-30 °C (the lower critical consolution point is 30.5 °C), which is in approximate agreement with results of our previous studies for dilute solutions. Relation to the existence of liquid crystal phases is also discussed. Measurements of dynamic light scattering have been made on D20 solutions of C,2Ej also. The data do not follow the scaling law even at higher temperatures, which may come from the fact that C12E8 micelles are much smaller than C12E5 micelles.(44) The concept of the 9 temperature has been introduced into micellar solutions already by Fujimatsu et al.. However, the method employed in the present study is completely different from theirs. See:

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