| Grtineisen parameterγis a very important parameter of condensed matters, which includes almost all of the information of the matter. It is a very difficult problem to acquire exact Gruneisen parameterγeven though it has been studied with various theoretical and experimental methods for years, because the data obtained from theoretical model can not be tested in experiment and the precision in the experiment is quite low.At first, the developing history of high pressure technology and the importance of the Gruneisen parameterγwere presented in this paper. Then the former investigations ofγwere surveyed and analyzed. The principle and advantages of technology of pressure-jump were also introduced.The main work in this paper will be listed as follows:(1) The relationship between the oil pressure and the actual pressure in the sample (iron, copper, aluminum and lead) was calibrated in Bridgman anvils by using the known phase transitions of bismuth and barium.(2) It is the first time that the method of larger pressure-jump was used to measure the Gruneisen parameter of iron, copper, aluminum and lead in Bridgman anvils. On the basis of Mean value Theorem; the data we obtained were accorded with the formula of the thermodynamic strictly.(3) Correction of the temperature change during the pressure-jump was made from both theory and experiment. In principal, the corrected experimental data could be regarded as the data in the perfectly adiabatic process, which solved the difficulty of achieving adiabatic compression in the experiment.(4) Gruneisen parameters of several representative mentals in a higher pressure range were measured. The tendency with pressure was also discussed. We obtained Gruneisen parameters of iron, copper, aluminum and lead under high pressure of 4.58GPa～7.49GPa, 4.40GPa～6.25GPa, 4.29GPa～6.90GPa and 2.39GPa～4.63GPa respectively. Obtained values ofΔT/ΔP andγdecrease gradually with the increasing pressure in the experimental ranges, their tendency with pressure is in good agreement with the previous work. And our work provides new values ofγin a larger range of pressure. It is an important supplement for the Gruneisen parameters of these mentals.(5) It is the first time that the Wu-Jing pameter R was measured by using the method of pressure-jump. It indicates that pressure-jump is a significant method for studing the Wu-Jing EOS. On the base of the experiments, we do some initial caculations on the Wu-Jing pameter of the several mentals.According to the analysis and recount in this paper, the method of larger pressure-jump is a new way for measurements of Gruneisen parameter. In principle, this method could be used to determine for all matters without phase transition at high pressure.In addition, the resistivity of PAN with different dopants and doped concentrations was measured in situ at high pressure in Bridgeman anvils. And the variation trends of the resistivity with pressure were also discussed. The conducting mechanism of PAN was analysized qualitatively on the base of the theory of energy band structure. The doped PAN under high pressure will be enhanced strongly in conductivity. This is mainly ascribed to the presence of polaron band and the increase of the carriers. However, with increasing the applied pressure, the scattering mechanism of carriers limits the conductivity of PAN.
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