We present new experimental results for the transport properties of Ni. In comparing these results to previously published values, we show that there exists a consistent group of experimental data which establishes reliably the transport properties of pure Ni from perhaps 30 to 1500 K. In the paramagnetic range (T > 630 K), these properties show three characteristic features: a positive slope of the thermal conductivity (which is equivalent to an electrical resistivity increasing less than linearly with temperature), a large negative thermopower, and a Lorenz function substantially larger than the Sommerfeld value, L0. In attempting to provide an explanation of these features, we have discovered that the model of Mott, wherein the electronic relaxation time is inversely proportional to the density of states, does not appear to be universally valid and, more importantly, that the observed properties cannot be consistently explained if we assume pure electron–phonon scattering. To achieve consistency, at least one other scattering mechanism has to be included, such as normal electron–electron scattering; this will be taken up in detail in a subsequent publication.

Epoxy‐grafted silicone oligomer (ESO), which has a linear silicone chain in the backbone moiety, was synthesized from a trifunctional alkoxysilane via a sol–gel reaction. Characterization of ESO was performed with 1H and 29Si NMR, Fourier transform infrared, and gel permeation chromatography. The number‐average molecular weight of ESO was 3300. By adding the silicone oligomer as the inorganic source in the curing process of the epoxy resin, novel epoxy/silica hybrid materials were prepared. It was observed by transmission electron microscope that fine silica‐rich domains of about 5‐nm diameter were uniformly dispersed in the cured epoxy matrix. Thermomechanical properties of the hybrid materials were also investigated. The storage modulus in the rubbery region and the peak area of the tan δ curve at the glass‐transition region increased and decreased, respectively, with the hybridization of the silica network. The mobility of the epoxy network chains should be considerably suppressed by the hybridization with the silica network. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1631–1639, 2005

The thermal conductivity, electrical resistivity, and thermoelectric power of well-characterized, polycrystalline specimens of pure Co have been determined in the temperature range of 90 to 1250 K. Additionally, the measurements of the electrical resistivity have been extended to 1750 K, and the coefficient of thermal expansion measured between 300 and 770 K. The new results are compared with those previously published, and, for the low temperature h.c.p. phase, compared with predictions based on published band structure calculations. Qualitatively, the observed results agree with the predictions, particularly as far as the very unusual temperature variation of the Lorenz function is concerned; quantitative comparisons, however, are impossible, due to the lack of precision in the calculated band structures. The theoretical analysis of the results for the high temperature f.c.c. phase will be given together with that of Ni in Part II.

Novel epoxy-based organic/inorganic hybrid materials filled with carbon black (CB) were synthesized from an epoxy resin and silane alkoxide via a sol-gel process. The phase structure and thermal and mechanical properties of the hybrid materials were studied in detail. It was revealed by transmission electron microscope observations that the filled CB particles formed a secondary aggregation structure and were uniformly dispersed in the aggregate. The storage modulus in the rubbery region increased and the peak area of the tan ␦ curve in the glass-transition region decreased with the hybridization of silica. Moreover, the conductive properties of the CB-filled hybrid systems were investigated. In the same volume fraction of CB, the conductivity of the hybrid systems was much higher than that of the unmodified system. This result was attributed to the excluded volume effect of the silica network.

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