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摘要翻译：
我们测量了两种接近Tg的分子玻璃形成体的线性介电磁化率，以估计动态关联的分子团簇的大小，这些分子团簇有望控制玻璃形成的物理过程。该尺寸与动态介电磁化率dEps(w)/dt（Eps：介电磁化率，T：温度，w：频率）有关。为了准确测定T导数，我们对甘油每1K扫描192<T<232K，对碳酸丙烯酯每0.5K扫描159<T<179K。对T变异的分辨率约为1 mK。对于甘油，当T从226 K到195K时，相关分子的数量增加了3倍。非线性磁化率可以直接测量动态相关。为了测量它，我们使用标准的Lockin技术，产生从电容器流出的电流的三次谐波。由于标准电子学的非线性响应，我们只得到了三次谐波与一次谐波之比的一个上限。
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英文标题：
《Experimental search for dynamic heterogeneities in molecular glass
formers》
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作者：
Fran\c{c}ois Ladieu (SPEC), Caroline Thibierge (SPEC), Denis L'H\^ote
(SPEC)
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最新提交年份：
2007
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分类信息：
一级分类：Physics 物理学
二级分类：Statistical Mechanics 统计力学
分类描述：Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变，热力学，场论，非平衡现象，重整化群和标度，可积模型，湍流
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英文摘要：
We have measured the linear dielectric susceptibility of two molecular glass formers close to Tg in order to estimate the size of the dynamically correlated clusters of molecules which are expected to govern the physics of glass formation. This size has been shown to be related to the dynamic dielectric susceptibility dEps(w)/dT (Eps : dielectric susceptibility, T : temperature, w: frequency). To allow for an accurate determination of the T derivative, we scanned the interval 192 < T < 232 K every 1 K for glycerol and 159 < T < 179 K every 0.5 K for propylene carbonate. The resolution on T variations was about 1 mK. The result for glycerol is that the number of correlated molecules increases by a factor 3 when T goes from 226 to 195 K. It has been shown that the non-linear susceptibility provides a direct measurement of dynamic correlations. To measure it, we used a standard Lockin technique yielding the third harmonic of the current flowing out of a capacitor. We obtained only an upper limit on the ratio of the third to the first harmonic, due to the non-linear response of standard electronics.
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PDF链接：
https://arxiv.org/pdf/707.3616
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