ABSTRACT The pressure effect on the electromotive force (EMF) of a Pt13Rh–Pt (type R) thermocouple was examined to determine the temperature measurement accuracy of solid pressure medium apparatuses in high-pressure experiments. Single-wire EMFs were measured up to pressure of 13 GPa and temperature of 1173 K with a Kawai-type multi-anvil apparatus for Pt13Rh and Pt based on the single-wire method. The pressure conditions along the wires were evaluated by in situ X-ray diffraction using synchrotron X-ray radiation. The pressure effect of the Seebeck coefficients of Pt13Rh and Pt were determined by the analysis of the single-wire EMFs and pressure–temperature profiles along the wires and was virtually consistent with those determined in previous studies at lower pressures and temperatures. For type R thermocouple, the difference between the nominal and real temperatures was determined to be as large as –75 K at 13 GPa and 873 K.

中文翻译：

---

压力对 R 型热电偶电动势的影响

摘要 压力对 Pt13Rh–Pt（R 型）热电偶的电动势 (EMF) 的影响被研究，以确定高压实验中固体压力介质设备的温度测量精度。基于单线法，使用 Kawai 型多砧装置对 Pt13Rh 和 Pt 进行了高达 13 GPa 的压力和 1173 K 的单线 EMF 测量。沿线的压力条件通过使用同步加速器 X 射线辐射的原位 X 射线衍射进行评估。Pt13Rh 和 Pt 的塞贝克系数的压力效应是通过对单线 EMF 和沿线的压力 - 温度曲线的分析确定的，并且与先前在较低压力和温度下的研究中确定的结果几乎一致。对于 R 型热电偶，