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Abstract: Using a single thermocouple as a heater and temperature sensor simultaneously, we have developed a new type of gas pressure sensor termed the Peltier vacuum gauge (PVG). The PVG measures gas pressure by allowing an AC current carrying thermocouple, which is in contact with gases, to measure its own temperature. An AC current carrying thermocouple generates Joule heating along the wire and Peltier heating/cooling at the junction, and its temperature is determined by the thermophysical properties of surrounding gases which in turn depends on pressure. The complementary nature of the Peltier effect and the Joule heating allows the PVG to possess an excellent sensitivity over a wide range of pressure from 10−4 Torr to atmospheric pressure. [Copyright &y& Elsevier]

A new AC calorimeter, utilizing the Peltier effect of a thermocouple junction as an AC power source, is described. This Peltier AC calorimeter (PAC) allows to measure the absolute value of heat capacity of small solid samples with sub-milligrams of mass. The calorimeter can also be used as a dynamic one with a dynamic range of several decades at low frequencies. [Copyright &y& Elsevier]

We developed an ac microcalorimeter utilizing the Peltier effect of a thermocouple junction as an ac power source. This Peltier microcalorimeter allows us to measure the absolute value of the heat capacity of small samples with submilligrams of mass. The performance of the microcalorimeter was checked in the temperature range of 15-420 K with α-Al[sub 2]O[sub 3] samples of 0.54 and 2.25 mg. The absolute accuracy was ±3% for the range of 30-150 K and ±1% for 150-420 K. The precision was better than 0.5% in the whole temperature range. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]