Table of contents

CONTENTS Introduction 209 1. General Properties. ρ-T, p-T, and v-T Diagrams 209 2. Refractive Index and Dielectric Constant 212 3. Compressibility and Thermal Expansion 212 4. Surface Tension 213 5. Adsorption 213 6. Sound in Helium, Zero Sound 213 7. Second Sound 214 8. Specific Heat 214 9. Heats of Phase Transitions 215 10. Entropy Diagram of He³ 215 11. Magnetic Properties 216 12. Relaxation Time 217 13. Spin Diffusion in He³ 217 14. Diffusion and Thermal Conductivity in Solutions of He³ in He⁴ 218 15. Thermal Conductivity of He³ 218 16. The Kapitza Jump 219 17. Viscosity 220 18. Experiments Aimed at Finding the Transition of Liquid He³ into the Superfluid Phase 220 19. Theoretical Estimates 221 20. Use of He³ to Obtain Very Low Temperatures 223 Conclusion 225 Cited Literature 225

CONTENTS Introduction 229 I. Study of the optical characteristics of shock-compressed condensed materials, and of the structure and smoothness of the fronts of large-amplitude shock waves 1. Experimental procedure 231 2. Front thickness and smoothness of shock waves in condensed inert and explosive substances 232 3. Density dependence of the refractive index of liquid dielectrics. Anomalous behavior of shock-compressed carbon tetrachloride 234 4. Investigation of the optical properties of shock-compressed ionic crystals. Nonequilibrium states 235 5. Optical study of elastoplastic waves in glass 237 6. Phase transition of water into ice VII under shock compression 238 II. Equilibrium radiation of the shock-wave front. Experimental determination of temperatures. 7. Possibility of temperature measurement in shock-compressed condensed materials. Principle of the method 240 8. Measurement of temperatures of shock-compressed ionic crystals and establishment of their melting curves for pressures up to 0.5-3 Mbar 241 9. Measurement of temperatures of shock-compressed lucite and carbon tetrachloride 245 III. Absorption of light by shock-compressed ionic crystals. Absorption and conduction mechanism. 10. Experimental determination of the absorption coefficient 245 11. Mechanisms of light absorption and conduction in shock-compressed ionic crystals 246 IV. Nonequilibrium radiation of shock-compressed ionic crystals 248 12. Nonequilibrium radiation at low temperatures. Electroluminescence of shock-compressed substances 248 13. Nonequilibrium radiation at high temperatures. Electronic screening of the radiation 249 References 251

Introduction I. Kinetic Phenomena in Dielectrics 256 1. Statement of the Problem 256 2. Hydrodynamic Mechanism of Thermal Conductivity 257 3. Influence of Higher-order Anharmonicity on Transfer Processes in Solids at Low Temperatures 259 4. Second Sound in Dielectrics 260 II. Kinetic Phenomena in Metals 5. Electrical Conductivity of Metals at Low Temperatures 262 6. Electrical Conductivity of Thin Samples 264 7. Electrical Conductivity of Bulk Samples 266 8. High-frequency Properties 268 References 269

From the Editors In publishing this letter by Ya. L. Al'pert, the editors conclude the discussion of his article "The Outer Ionosphere and Its Transition to the Interplanetary Medium," deeming a continuation of this discussion inadvisable.