Topic
Calorimeter
About: Calorimeter is a research topic. Over the lifetime, 5878 publications have been published within this topic receiving 77157 citations.
Papers published on a yearly basis
Papers
More filters
13 Jul 1998
30 citations
TL;DR: In this article, a computerized adiabatic calorimeter system operating in the temperature range 13-300 K is described, where a digital voltmeter is used for energy measurement and the duration of energy input is determined by a program unit operated by 1 Hz pulse.
Abstract: A computerized adiabatic calorimeter system operating in the temperature range 13–300 K is described. A digital voltmeter is used for energy measurement and the duration of energy input is determined by a program unit operated by 1 Hz pulse. Temperatures of the calorimeter are measured by a 25 Ω platinum resistance thermometer and an automated ac double bridge. The measured resistance is converted into temperature (IPTS-68) by a calibration table stored in a mini-computer. Criterion for the realization of thermal equilibration is that a temperature drift calculated from the latest six data becomes smaller than a preset value, usually 7×10−8 Ω s−1. The system is able to measure the heat capacity of solid and liquid in an intermittent heating mode and gives the computed results during measurement. Some examples of the test runs on cyclohexanol crystal are shown and the results are compared with those obtained by manual measurements by use of dc Muller bridge. A relaxational heat capacity anomaly observed in...
30 citations
TL;DR: In this article, a portable calorimeter that measures heat output from the steaming ground found in areas of natural thermal activity is described, with a minimum of disturbance to the site, heat flow is measured in a range from 10 to 70×10−3 cal/cm2 sec with an accuracy better than 10 per cent.
Abstract: A portable calorimeter that measures heat output from the steaming ground found in areas of natural thermal activity is described. With a minimum of disturbance to the site, heat flow is measured in a range from 10 to 70×10−3 cal/cm2 sec with an accuracy better than 10 per cent. Below this range, the accuracy decreases. The relationship of heat output to the soil temperatures measured at a depth of 35 cm is shown for measurements at 27 different sites.
30 citations
TL;DR: In this article, a high resolution and super-sensitive differential scanning calorimetry (DSC) has been constructed by using two kinds of semi-conducting thermoelectric modules; one is used as a high-sensitive heat flow sensor and the other is for a main heater or cooler using the Peltier effect.
30 citations
TL;DR: Measurements performed in graphite over a wide range of phantom depths, field sizes, and source distances, showed that the calibration factor varies slowly with the phantom depth and field size, and probably has a negligible dependence on source distance.
Abstract: Absorbed dose to water in a cobalt-60 gamma-ray beam has been determined using a thick-walled graphite ionization chamber. The chamber was calibrated in a graphite phantom against a graphite calorimeter, and the graphite calibration factor was converted to a water calibration factor using published energy absorption coeffi cient ratios and a measured replacement factor. Comparisons between the graphite and water measurements were made at pairs of points that were scaled in position according to the ratio of electron densities, so that the photon spectra were the same for the two points in a given pair. Measurements performed in graphite over a wide range of phantom depths, field sizes, and source distances, showed that the calibration factor varies slowly with the phantom depth and field size, and probably has a negligible dependence on source distance. By com parison with the thick-walled chamber in a cobalt-60 gamma-ray beam, a secondary ionization chamber can be calibrated in terms of absorbed dose to water with an estimated uncertainty of about ± 1 percent.
30 citations