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
••
TL;DR: In this article, a microfluid chip calorimeter measuring system with highly stable thermostat (0.1mK) was developed based on an improved nano calorimetry thin-film thermopile chip with excellent chemical and mechanical reliability fabricated in SU-8 technology for insulation and passivation layers.
Abstract: A micro-fluid chip calorimeter measuring system with highly stable thermostat (0.1 mK) was developed based on an improved nano calorimetry thin-film thermopile chip with excellent chemical and mechanical reliability fabricated in SU-8 technology for insulation and passivation layers. Biochemical processes (e.g. enzyme catalyzed reaction) can be investigated with heat power detection limit
71 citations
••
TL;DR: In this article, the shape of the interpolated baseline under a peak is determined by a change in the heat capacity of the sample and the heat transfer characteristics between sample and temperature sensor.
Abstract: In DSC's the shape of the interpolated baseline under a peak is determined by a change in the heat capacity of the sample and the heat transfer characteristics between sample and temperature sensor. The interpolated baseline is constructed according to formal criteria, experimentally or analytically on the basis of physico-chemical assumptions on the change of the heat capacity during transition. By the example of the melting of ice this paper shows analytically on the basis of a simple calorimeter model and a synthetic measuring curve, and experimentally, that the uncertainty of the enthalpy determination depends in general on the type of baseline and is in the order of magnitude of the repeatability of the DSC's (±0.5%).
70 citations
••
TL;DR: The NIST sealed water calorimeter was used for a series of approximately 3700 measurements to investigate the so-called heat defect, that is, anomalous endothermic or exothermic effects caused by dissolved gases.
Abstract: National Institute of Standards and Technology, Gaithersburg, MD 20899-0001 The NIST sealed water calorimeter is intended for direct measurement of absorbed dose to water. This calorimeter was used for a series of approximately 3700 measurements to investigate the so-called heat defect, that is, anomalous endothermic or exothermic effects caused by dissolved gases. The three systems investigated were "high-purity" water saturated with N2, H2, and mixtures of H2/O2. The repeatability of the measurements of absorbed dose rates for the '*"Co teletherapy beam was studied with different water fillings and accumulated absorbed dose. Measurements with the H2/O2 system varied with accumulated absorbed dose. Based on the measurements and theoretical considerations, it appears that the H2saturated system is the best choice for eliminating the heat defect. Measurements with both the N2and H2-saturated systems are in good agreement with those determined with a graphite and graphite-water calorimeter (for which there is no heat defect).
70 citations
••
TL;DR: In this article, an adiabatic scanning calorimeter has been used in a calorimetric investigation of alkyl-cyanobiphenyl (nCB) liquid crystals.
Abstract: An adiabatic scanning calorimeter has been used in a calorimetric investigation of alkyl-cyanobiphenyl (nCB) liquid crystals. Measurements near solid to smectic (KA), smectic A to nematic (AN) and nematic to isotropic (NI) or smectic A to isotropic (AI) phase transitions have been carried out for scanning rates as low as a few μKs−1. Results for the temperature dependence of the heat capacity as well as for the enthalpy (including latent heats) have been obtained for 8CB, 9CB, 10CB and 11CB. Latent heat values are reported for the different KA, NI and AI transitions. For the two compounds 8CB and 9CB, which show a AN transition, it was found that, within the resolution of the experiments, these transitions are second-order. The anomalous heat capacity observed near the AN transition is much larger for 9CB than for 8CB. The critical exponent α obtained from power law fits to the heat capacity data is 0.31 ± 0.03 for 8CB and 0.50 ± 0.05 for 9CB. It is suggested that the AN transition in 9CB must be...
70 citations
••
TL;DR: In this paper, a scanning calorimeter was introduced for use with a single solid or liquid sample with a volume down to a few nanoliters, which was demonstrated with the melting of 52 nL of indium, using heating rates from 100 to 1000 K/s.
Abstract: We introduce a scanning calorimeter for use with a single solid or liquid sample with a volume down to a few nanoliters. Its use is demonstrated with the melting of 52 nL of indium, using heating rates from 100 to 1000 K/s. The heat of fusion was measured to within 5% of the bulk value, and the sensitivity of the measurement was ±7 μW. The heat of vaporization of water was measured in the scanning mode to be within ±23% of the bulk value by actively vaporizing water droplets from 2 to 100 nL in volume. Results within 25% were obtained for the heat of vaporization by using the calorimeter in a heat-conductive mode and measuring the passive evaporation of water. Temperature measurements over a period of 10 h had a standard deviation of 3 mK.
70 citations