The thermal equilibrium state of the reference electrode was investigated. The results show that the temperature difference between the inside and the outside of zirconia tube was very small and the Seebeck effect can...The thermal equilibrium state of the reference electrode was investigated. The results show that the temperature difference between the inside and the outside of zirconia tube was very small and the Seebeck effect can be ignored after the sensor was dipped into liquid steel for more than 2 s. A special sensor was designed to test the relation between the EMF (electromotive force) of sensor and the thermal equilibrium state of the reference elec- trode. Based on these results, it is suggested that the peak in EMF curve was caused by the change of oxygen potential in reference electrode before the thermal equilibrium was reached. If NiO was added by 2 M- 5 M to the Cr/Cr2O3 reference electrode, the peak in EMF curve could be eliminated.展开更多
The ZrO2 (9mol% Y2O3) coating was prepared evenly on the surface of MgO partially stabilized zirconia (Mg-PSZ) tube (oxygen sensor probe) by dipping the green Mg-PSZ tube in a ZrO2 (9mol% Y2O3) slurry and then co-firi...The ZrO2 (9mol% Y2O3) coating was prepared evenly on the surface of MgO partially stabilized zirconia (Mg-PSZ) tube (oxygen sensor probe) by dipping the green Mg-PSZ tube in a ZrO2 (9mol% Y2O3) slurry and then co-firing at 1750°C for 8 h. The double-cell method was employed to measure the electronic conductivity parameter and exam the reproducibility of the coated Mg- PSZ tube. The experimental results indicate that the good thermal shock resistance of the Mg-PSZ tube can be retained when the coating thickness is not more than 3.4 μm. The ZrO2 (9mol% Y2O3) coating reduces the electronic conductivity parameter remarka- bly, probably due to the lower electronic conductivity of Y2O,-stabilized ZrO2 than that of MgO-stabilized ZrO2. Moreover, the ZrO2 (9mol% Y2O3) coating can improve the reproducibility and accuracy of the Mg-PSZ tube significantly in the low oxygen measure- ment. The smooth surface feature and lower electronic conductivity of the coated Mg-PSZ tube should be responsible for this im- provement.展开更多
设计一种基于氧化锆(Zr O2)的高温非共烧陶瓷压力传感器。在已有的低温共烧陶瓷(LTCC)工艺的基础上,经过改进采用了高温非共烧技术进行陶瓷传感器的制作。先进行传感器基底的制作,再制作传感器的金属电路部分。这样解决了高温共烧技术...设计一种基于氧化锆(Zr O2)的高温非共烧陶瓷压力传感器。在已有的低温共烧陶瓷(LTCC)工艺的基础上,经过改进采用了高温非共烧技术进行陶瓷传感器的制作。先进行传感器基底的制作,再制作传感器的金属电路部分。这样解决了高温共烧技术中各材料高温烧结热膨胀系数不匹配的问题。传感器信号读取采用两个电感耦合的方式,实现了非接触压力测量。制作的传感器高温环境下力学特性稳定。测试结果显示:传感器的谐振频率随外加压力的增加而减小,其谐振频率变化对压力的响应灵敏度约为491.10 k Hz/bar。展开更多
In order to in situ measure chemical parameters of deep-sea water and hydrothermal fluids at midocean ridge(MOR),it is necessary to use high temperature and high pressure chemical sensors.Developing new sensors is ess...In order to in situ measure chemical parameters of deep-sea water and hydrothermal fluids at midocean ridge(MOR),it is necessary to use high temperature and high pressure chemical sensors.Developing new sensors is essential to measure in-situ pH and other chemical parameters(dissolved H2,dissolved H2S)of deep-sea water and hydrothermal fluids in a wide temperature range(2℃―400℃)at MOR vents.The YSZ(Yttria Stabilized Zirconia,9%Y2O3)ceramic-based(HgO/Hg)chemical sensors possess excellent electrochemical properties at high temperatures,which have been used to measure chemical parameters of hydrothermal fluids above 200℃.A novel Zr/ZrO2 oxidationeduction electrode was constructed by oxidation of Zr wire in Na2CO3 melt.This Zr/ZrO2 electrode has good chemical stability while measuring pH of high-temperature aqueous solutions,combined with a Ag/AgCl reference electrode.Potentials of the Zr/ZrO2 sensor in association with a Ag/AgCl reference electrode vary linearly with pH over a wide pH range,as tested by various NaCl-HCl-H2O solutions(NaOH-NaCl-H2O for basic solutions),at temperatures in the range of 20℃―200℃.Thus,the Zr/ZrO2 sensors can be utilized in monitoring the fluids over the temperature range of 2℃―200℃.The Zr/ZrO2 electrode combined with Ag/AgCl,Ag/Ag2S,and Au electrodes has been used to measure pH and other chemical parameters(dissolved H2,dissolved H2S)of aqueous fluids from low to high temperatures and high pressures in the laboratory and to monitor those parameters of deep-sea water in South China Sea.展开更多
摘要The thermal equilibrium state of the reference electrode was investigated. The results show that the temperature difference between the inside and the outside of zirconia tube was very small and the Seebeck effect can be ignored after the sensor was dipped into liquid steel for more than 2 s. A special sensor was designed to test the relation between the EMF (electromotive force) of sensor and the thermal equilibrium state of the reference elec- trode. Based on these results, it is suggested that the peak in EMF curve was caused by the change of oxygen potential in reference electrode before the thermal equilibrium was reached. If NiO was added by 2 M- 5 M to the Cr/Cr2O3 reference electrode, the peak in EMF curve could be eliminated.
摘要The ZrO2 (9mol% Y2O3) coating was prepared evenly on the surface of MgO partially stabilized zirconia (Mg-PSZ) tube (oxygen sensor probe) by dipping the green Mg-PSZ tube in a ZrO2 (9mol% Y2O3) slurry and then co-firing at 1750°C for 8 h. The double-cell method was employed to measure the electronic conductivity parameter and exam the reproducibility of the coated Mg- PSZ tube. The experimental results indicate that the good thermal shock resistance of the Mg-PSZ tube can be retained when the coating thickness is not more than 3.4 μm. The ZrO2 (9mol% Y2O3) coating reduces the electronic conductivity parameter remarka- bly, probably due to the lower electronic conductivity of Y2O,-stabilized ZrO2 than that of MgO-stabilized ZrO2. Moreover, the ZrO2 (9mol% Y2O3) coating can improve the reproducibility and accuracy of the Mg-PSZ tube significantly in the low oxygen measure- ment. The smooth surface feature and lower electronic conductivity of the coated Mg-PSZ tube should be responsible for this im- provement.
摘要设计一种基于氧化锆(Zr O2)的高温非共烧陶瓷压力传感器。在已有的低温共烧陶瓷(LTCC)工艺的基础上,经过改进采用了高温非共烧技术进行陶瓷传感器的制作。先进行传感器基底的制作,再制作传感器的金属电路部分。这样解决了高温共烧技术中各材料高温烧结热膨胀系数不匹配的问题。传感器信号读取采用两个电感耦合的方式,实现了非接触压力测量。制作的传感器高温环境下力学特性稳定。测试结果显示:传感器的谐振频率随外加压力的增加而减小,其谐振频率变化对压力的响应灵敏度约为491.10 k Hz/bar。
基金Supported by the"863"Project of the Ministry of Science and Technology of China(Grant Nos.2001AA612020-3,2003AA612020-3,2001DEA30041,2002DEA30084,2003DEA2C021,2001DEA20023B,DY105-03-01,K2007-1-13)the National Natural Science Foundation of China(Grant Nos.20373064,50602042)
摘要In order to in situ measure chemical parameters of deep-sea water and hydrothermal fluids at midocean ridge(MOR),it is necessary to use high temperature and high pressure chemical sensors.Developing new sensors is essential to measure in-situ pH and other chemical parameters(dissolved H2,dissolved H2S)of deep-sea water and hydrothermal fluids in a wide temperature range(2℃―400℃)at MOR vents.The YSZ(Yttria Stabilized Zirconia,9%Y2O3)ceramic-based(HgO/Hg)chemical sensors possess excellent electrochemical properties at high temperatures,which have been used to measure chemical parameters of hydrothermal fluids above 200℃.A novel Zr/ZrO2 oxidationeduction electrode was constructed by oxidation of Zr wire in Na2CO3 melt.This Zr/ZrO2 electrode has good chemical stability while measuring pH of high-temperature aqueous solutions,combined with a Ag/AgCl reference electrode.Potentials of the Zr/ZrO2 sensor in association with a Ag/AgCl reference electrode vary linearly with pH over a wide pH range,as tested by various NaCl-HCl-H2O solutions(NaOH-NaCl-H2O for basic solutions),at temperatures in the range of 20℃―200℃.Thus,the Zr/ZrO2 sensors can be utilized in monitoring the fluids over the temperature range of 2℃―200℃.The Zr/ZrO2 electrode combined with Ag/AgCl,Ag/Ag2S,and Au electrodes has been used to measure pH and other chemical parameters(dissolved H2,dissolved H2S)of aqueous fluids from low to high temperatures and high pressures in the laboratory and to monitor those parameters of deep-sea water in South China Sea.