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This study is based on the seismic data collected as a result of explosions carried out during the 1976 and 1978 Deep Seismic Sounding (DSS) field operations in the Koyna region. These shots were exploded from twelve shot points by the National Geophysical Research Institute along the Guhagar-Chorochi and Kelsi-Loni profiles. Refraction studies of the records reveal a two-layered crust. The top layer consists 17 km of granite and the second layer 19 km of basalt, giving the average depth of the Moho as 36 km in the region. The velocities of the phases Pg, P∗ and Pn have been computed as 5.82 ± 0.01, 6.61 ± 0.05 and 8.23 ± 0.05 km/sec respectively and those of Sg, S∗ and Sn as 3.41 ± 0.00, 4.09 ± 0.07 and 4.60 ± 0.08 km/sec respectively. The shear wave velocity in the basement rock has been found to be lower in comparison with other regions of the peninsular India. In some cases reflections were recorded both from the Moho as well as from the intermediate layer. These reveal a crustal thickness of 39 km with 19 km of granitic and 20 km of basaltic layers. Coda signal durations from DSS explosions recorded by microearthquake seismographs indicate a lateral heterogeneity in the crust on either side of Karad in an east-west direction.

Introducing a parameter a which determines the relative strength of normal and umklapp phonon processes, the correction to phonon conductivity of undoped and doped Ge due to normal processes has been estimated in the framework of Callaway's model in the temperature range from 2 to 80 K for various values of a ranging from 0.1 to 10. There is an overall increase in the correction term with the increase in temperature, the maximum being below 10%.

Temperature dependence of the density-of-states effective mass is obtained in the case of the heavily doped semiconductors for which the impurity levels merge with the conduction band and Ziman scattering of phonons by conduction electrons is the relevant scattering. Phonon conductivity results of Sb- and As-doped Ge are used to obtain the values of m∗ in the range 1 to 20 K.

Anderson's theory has been used to explain the temperature dependence of the adiabatic bulk modulus of KCl, NaCl, LiF and TlBr in the temperature range up to the melting point of the material. In KCl and LiF, the value of δ which gives good agreement between theory and experiment is that which is obtained from the pressure dependence of B s . In NaCl the value of δ for the best fit is the one obtained from the temperature coefficient of ln B s . In TlBr Chang's relation δ = 2 γ , however, gives a better agreement between the observed temperature dependence of B s and the theoretical values.

The theoretical model of Callaway for lattice thermal conductivity at low temperatures is compared with the experimental results in ZnF 2 , CaF 2 , PbS and InSb. Good agreement between the theory and experiment is obtained in all the cases. The present analysis of the results in ZnF 2 and PbS indicate the presence of microscale fluctuations in the composition of the solid. In CaF 2 and PbS the impurity scattering is predominant. In InSb boundary scattering is negligible in the temperature range in which the data are available.

It has been shown in the present work that one can explain the residual resistivity of dilute binary alloys of Al, Mg, Pb and In, quite satisfactorily on the basis of Harrison's formula and single parameter model pseudopotential.