Impedance spectroscopy measurements to study physio-chemical processes in lime-based composites
Impedance spectroscopy measurements to study physio-chemical processes in lime-based composites
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DOI：
10.1007/s00339-011-6509-7
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发表时间：
2011-07
期刊：
影响因子：
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通讯作者：
R. Ball;G. C. Allen;G. Starrs;W. McCarter
中科院分区：
文献类型：
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作者：
R. Ball;G. C. Allen;G. Starrs;W. McCarter
两种不同等级的天然水硬性石灰的导电和介电性能在1 Hz-1 MHz的频率范围内呈现，在用水测量后的最初六个月内进行测量。将含有嵌入式电极的样品暴露于自然气氛（20°C和65%相对湿度）和二氧化碳浓度保持在400 ppm的自然气氛，其用于加速碳酸化过程。随着频率的增加，相对介电常数下降，电导率上升，在所有阶段的时间尺度上观察到。当绘制在复平面中时，阻抗的特征是体响应，包括两个凹陷的半圆和一个低频杂散，后者与电极/样品界面相关。复阻抗图，连同应用的等效电路模型，表明了双弧功能与碳酸化和水化有助于体阻抗响应。这项研究表明，电性能测量的适用性，以监测这组材料的水化和碳酸化的组合过程。
The conduction and dielectric behaviour of two different grades of natural hydraulic lime is presented over the frequency range 1 Hz–1 MHz, with measurements taken over the initial six months after gauging with water. Samples containing embedded electrodes were exposed to both a natural atmosphere (20°C and 65% relative humidity) and a natural atmosphere with a carbon dioxide concentration maintained at 400 ppm which was used to accelerate the carbonation process. A decrease in relative dielectric permittivity and rise in conductivity, with increasing frequency, was observed at all stages over the time-scale presented. When plotted in the complex plane, the impedance featured a bulk response comprising two depressed semicircles and a low frequency spur, the latter being associated with the electrode/sample interface. The complex impedance plot, together with the application of an equivalent circuit model, indicated a dual arc feature with carbonation and hydration contributing to bulk impedance response. This study demonstrates the applicability of electrical property measurements to monitor the combined processes of hydration and carbonation in this group of materials.