It is interesting to maximize the amount of information we can obtain from one experiment on a single sample.In obtaining all the thermodynamic properties of some materials from their experimental heat capacity data o...It is interesting to maximize the amount of information we can obtain from one experiment on a single sample.In obtaining all the thermodynamic properties of some materials from their experimental heat capacity data only,we aim to get the temperature-independent energy spectrum.However,all the practical measured energy spectra depend on the temperature of experiments.One promising method to obtain the temperature-independent energy spectrum is to solve the so-called specific heat-phonon spectrum inversion(SPI) problem.Here we show,by developing a new practical solution method of SPI,the phonon spectrum of the negative thermal expansion material ZrW 2 O 8 is obtained.This phonon spectrum is temperature-independent and almost method independent.Hence all the thermodynamic properties of ZrW 2 O 8,such as thermodynamic potential,entropy,Helmholtz free energy,etc.are obtained by heat capacity only.展开更多
The effective temperature of the solar photosphere is usually obtained according to the solar constant, based on the Stefan-Boltzmann law. However its temperature distribution is not homogeneous. A hopeful way to obta...The effective temperature of the solar photosphere is usually obtained according to the solar constant, based on the Stefan-Boltzmann law. However its temperature distribution is not homogeneous. A hopeful way to obtain the area-temperature distribution of the solar photosphere is to solve the Black-body Radiation Inversion (BRI) problem. In this paper, a new practical solution method for BRI is developed. The theoretical analysis and numerical calculations show the low-temperature distribution difficulty of BRI is solved by this new method. Then the area-temperature distribution of the solar photosphere is obtained, according to the measured absolute solar spectral irradiance. It is the first realization of BRI for a real system after almost three decades of efforts. The results are comparable to that from the Stefan-Boltzmann law.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 10675031,10375012 and 19975009)the Department of Education of Zhejiang Province (Grant No. Y200906911)
文摘It is interesting to maximize the amount of information we can obtain from one experiment on a single sample.In obtaining all the thermodynamic properties of some materials from their experimental heat capacity data only,we aim to get the temperature-independent energy spectrum.However,all the practical measured energy spectra depend on the temperature of experiments.One promising method to obtain the temperature-independent energy spectrum is to solve the so-called specific heat-phonon spectrum inversion(SPI) problem.Here we show,by developing a new practical solution method of SPI,the phonon spectrum of the negative thermal expansion material ZrW 2 O 8 is obtained.This phonon spectrum is temperature-independent and almost method independent.Hence all the thermodynamic properties of ZrW 2 O 8,such as thermodynamic potential,entropy,Helmholtz free energy,etc.are obtained by heat capacity only.
基金supported by the National Natural Science Foundation of China (Grand Nos. 10675031, 10375012 and 19975009)supported in part by the Department of Education of Zhejiang Province (Grant No. Y200906911)
文摘The effective temperature of the solar photosphere is usually obtained according to the solar constant, based on the Stefan-Boltzmann law. However its temperature distribution is not homogeneous. A hopeful way to obtain the area-temperature distribution of the solar photosphere is to solve the Black-body Radiation Inversion (BRI) problem. In this paper, a new practical solution method for BRI is developed. The theoretical analysis and numerical calculations show the low-temperature distribution difficulty of BRI is solved by this new method. Then the area-temperature distribution of the solar photosphere is obtained, according to the measured absolute solar spectral irradiance. It is the first realization of BRI for a real system after almost three decades of efforts. The results are comparable to that from the Stefan-Boltzmann law.
