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 paper, a micro-combustion calorimetry system was used to obtain reliable standard energies of combustion with small amounts of C, H, O compounds, and a new micro-calorimetric system was set up.
Abstract: To obtain reliable standard energies of combustion with small amounts of C, H, O compounds, a new microcombustion calorimetry system has been set up. The design, construction, calibration and measurement experiments are described. The system includes a commercial combustion bomb with an internal volume of 22 cm3. Samples of around 80 mg are suitable if one wants to retain the same levels of accuracy and reproducibility as those in macrocombustion experiments. Calibration of the calorimeter was performed using benzoic acid. e(calorimeter) = 2083.74±0.48JK-1 was obtained. Combustion measurements using m-methoxybenzoic acid were made in order to verify the chemistry of the combustion process involved in the corresponding analysis of results and the accuracy of the measurement of combustion energy. The uncertainty of the results shows that the instrument described and the experimental procedure used for the determination of enthalpies of formation of compounds containing C, H and O provide a high reliability.
26 citations
TL;DR: In this article, the authors determined the heat of adsorption of oxygen on germanium and silicon films with an absolute accuracy of ± 5 percent by means of a Beeck type calorimeter.
26 citations
Patent•
12 Jul 2004
TL;DR: In this article, a new adiabatic scanning calorimeter allows the thermal mass of a high-pressure reaction vessel to be dynamically compensated during a test, which allows the effective Φ factor for the experiment to be reduced to 1.0 without the use of complex pressure balancing equipment.
Abstract: A new adiabatic scanning calorimeter allows the thermal mass of a high-pressure reaction vessel to be dynamically compensated during a test. This allows the effective Φ factor for the experiment to be reduced to 1.0 without the use of complex pressure balancing equipment. Endothermic events can be quantified and sample specific heats can be measured. The time required for test completion is much shorter than for conventional adiabatic calorimeters, thus considerably improving apparatus productivity. The sensitivity to exotherm detection is at least as good as existing adiabatic calorimeters employing the Heat-Wait-Search strategy, but does depend on the temperature-scanning rate. In addition, the heat of reaction is obtained without reference to the heat capacity of the sample, pressure is measured continuously, reactants may be injected into the test vessel and the sample can be mixed during the test.
26 citations
TL;DR: A design for a flow‐microcalorimeter that uses a two hundred junction thermopile detector between twin calorimeter regions to accomplish Mixing of two thermally equilibrated solutions without a vapor space or mechanical stirring is described.
Abstract: A design for a flow‐microcalorimeter is described. The instrument uses a two hundred junction thermopile detector between twin calorimeter regions. Mixing of two thermally equilibrated solutions is accomplished without a vapor space or mechanical stirring in one of the twin cells. The attendant heat effects are measured using servo‐controlled electrical heating. Well controlled thermal shields are used to provide both precise thermal equilibration of the solutions and adequate isolation for the twin calorimeter elements. Heat effects of 1 mcal have been measured with a precision of 1% for a steady state experiment where two reactants are mixed together at equal flow rates of 10−3 cc/sec and the attendant heat effects are measured during a 100 sec time interval. A pulsed flow experiment in which mixing of 0.1 cc of each reactant is allowed to occur for the same time interval is also feasible, but gives measurements with lower precision.
26 citations
TL;DR: In this paper, a single-pan scanning calorimeter has been developed that eliminates the smearing of latent heat that occurs in a conventional two-pan heat-flux differential scanning (DSC) differential scanner.
Abstract: A single-pan scanning calorimeter has been developed that eliminates the smearing of latent heat that occurs in a conventional two-pan heat-flux differential scanning calorimeter (DSC) In the new calorimeter, accurate enthalpy/temperature data was obtained in pure Al without smearing, and excellent sensitivity to new phases was obtained in a multicomponent Al alloy (LM25) The calorimeter has been used to investigate microsegregation in an Al-445 wt pct Cu alloy The enthalpy/temperature data fell between that calculated, assuming no mixing in the solid (Scheil) and complete mixing in the solid (equilibrium solidification) The amount of segregation agreed well with that calculated using a diffusion-based model of microsegregation The difficulty of getting the fraction solid from the enthalpy data is discussed, and it is concluded that it is not possible to do so without using a microsegregation model In addition, it is concluded that it is wrong to assume that the enthalpy of an alloy can be given by a specific heat term and a constant latent heat term that depend on fraction liquid as is assumed in most casting models
26 citations