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提出了微分和二次微分时域介电谱方法。极化响应可描述为exp[-(t/τ)α]类型若干个分得很开的峰,峰的线型决定α,它有1和1/2两个典型值.极化机构种类和峰的个数相等,峰高给出各机构对极化贡献的成份.响应时间τ由峰的位置定决,谱线的分离说明习惯设α=1而令τ有连续分布的看法缺乏根据,在石蜡中观察到温度升高时,指数增大,石蜡熔解过程中出现时域谱线分裂,从中可得到分子链运动的许多信息。The first and second order differential dielectric spectra have been first presented to seperate various polarizations of material conveniently and definitelly in the time domain measurement. The polarization response function introduced traditionaly as the form of exp(-(t/τ)α) can be deter-mined by the differential spectral curve. The experiments show that there are two typical differential spectral curves corresponding to τ=1 and τ-1/2. The number of the polarization mechanisms, the individual mechanism contribution to the total polarization and its response time τ can be derived from the number, the height and the location of peaks of the differential spectral curves. The seper-ability of the differential spectral curves indicates that there is no reason for the conventional assump-tion that τ has some distribution function while a is a constant. The measurements on paraffin sam-ple demonstrate the slow polarization informations about the motions of the localized segment and the whole of a molecular chain in the process of the paraffin melting. The experiments also give the re-sult that the response time τ increases exponentially with temperature which is in contradistinction from the temperature dependence of relaxation time followed from frequency domain measurement.
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