Effect of Impurities on Thermal Decomposition of Calcium Carbonate

1016-101

Kinetics of Ce(IV) Oxidation of Monothioglycerol in Carbonate Medium

656-65

Alkoxide Complexes of Some Tri- & Tetra-valent Metals: Part I- Conductometric & Potentiometric Studies on Some Aluminium Alkoxide Complexes in Non-aqueous Solvents

256-25

Reactions of Pyruvonitrile with Nb(V) & Ta(V) Alkoxides

406-40

Kinetics of Hexacyanoferrate(III) Oxidation of 4-tert-Butylthiophenol & 2-Merhyl-a-tert-butylrhiophenol

252-25

Parametric Generation of Second Sound by First Sound in Superfluid Helium

We report the first experimental observation of parametric generation of second sound (SS) by first sound (FS) in superfluid helium in a narrow temperature range in the vicinity of $T_\lambda$. The temperature dependence of the threshold FS amplitude is found to be in a good quantitative agreement with the theory suggested long time ago and corrected for a finite geometry. Strong amplitude fluctuations and two types of the SS spectra are observed above the bifurcation. The latter effect is quantitatively explained by the discreteness of the wave vector space and the strong temperature dependence of the SS dissipation length.Comment: 4 pages, 4 postscript figures, REVTE

Observation of Crossover from Ballistic to Diffusion Regime for Excimer Molecules in Superfluid 4^4He

We have measured the temperature dependence of the time of flight of helium excimer molecules He2* in superfluid 4He and find that the molecules behave ballistically below 100mK and exhibit Brownian motion above 200 mK. In the intermediate temperature range the transport cannot be described by either of the models.Comment: 8 pages, 6 figures, submitted to the Proceedings of the International Conference on Quantum Fluids and Solids 201