Nanometrology and high-precision temperature measurements under the temperature conditions varying in time temperature conditions

Abstract

Significant progress in high-precision temperature measurements of material artifacts has been achieved as a result of a development of a new approach which takes explicitly into account the effect of a heat waves propagation in a sample. The approach requires a complete change of a routine procedure in temperature measurements. In order to detect the time delay in a heat wave propagation, it is necessary to have two detectors which synchronously measure the temperatures and temperature rates in two different points of a sample. When these four parameters are recorded for a number of slow heating and cooling procedures, the measurement results can be corrected on the velocity error, which is associated with the time delay in the wave propagation between the two measurement points on a sample. As an intermediate result in the new method, we obtain the value of the thermal field variation (temperature gradient) between the two points of the artifact. We also use a special type of synchronous detection, with a complete averaging within a half-cycle of a modulation procedure, in order to measure precisely a self-heating effect of a resistance thermometer, which is attached to the artifact surface,. This results in a reduction of the uncertainty of measurements to a few µK level.

Experimental Demonstration of the Relational Character of Time in Natural Processes; Concept of Time in the Relational World

“…All these experiments were based on the original method of synchronous differential thermal measurements [14,15], which was based on the periodic modulation of the input flux of energy to the investigated system and on the signal averaging procedure within one modulation cycle [16]. Using this method, the first observations and the studies of the thermal surface energy [16,17] and of the thermal evolution process were realized [18][19][20][21].…”

“…The key feature of these temperature measurements was the special procedure of calibration of thermometers. Each thermistor (sealed in a copper adapter) was calibrated together with the particular unit of the multi-meter on the surface of a long steel gauge block that was located inside the temperature stabilized Kősters interferometer [14,15]. As a reference in these calibrations we used a 25-Ohm Rosemount standard platinum resistance thermometer (SPRT 162E, produced in USA) and an automatic precision DC MI-bridge T615 (Canada), or the Guildline current comparator 9975 (when necessary).…”

“…As a reference in these calibrations we used a 25-Ohm Rosemount standard platinum resistance thermometer (SPRT 162E, produced in USA) and an automatic precision DC MI-bridge T615 (Canada), or the Guildline current comparator 9975 (when necessary). The calibration procedure was described in some detail in [14,22,23] and was giving the opportunity to measure the temperature of the surface of a steel artifact in the close proximity to the boundary of the thermistor adapter. In the calibration procedure realized in these experiments, the measured resistance value of a thermistor, corresponding to each temperature of the gauge block surface, was compared with the resistance of a temperature stabilized standard resistor with the nominal value of 10-kOhm.…”

“…The positive values of T[1,2] mean that these series of measurements were performed when the heat source No.2 in Fig.1 was switched on. As the distribution of temperature in a well thermally-isolated homogeneous gauge block is a non-linear function of the displacement of a thermometer along the length of a gauge block [14] (Fig. 8), the activation of the heat source No.2 produced a much larger temperature difference T [1,2] between the positions of the thermistors 1 and 2 than the activation of the heat source No.1 (for the same level of dissipated power).…”

New Studies of Thermal Evolution Process

“…The use of the adapters gave the possibility to reduce drastically the temperature gradients in the contacts between the surfaces of the GB and the adapters, so that it opened the opportunity to realize the calibration of the self-heating of the thermometers on the surface of a particular material with a few μK uncertainty [9,10]. In our experiments, the calibration of the measuring channels 1 and 2 was realized inside the Kōsters interferometer equipped with its own temperature stabilizing system, so that temperature gradients in the gauge block (on whose surface the calibrations were performed) were an order of magnitude smaller than in case of our Dewar system.…”