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Abstract  

European Conference on Calorimetry and Thermal Analysis for Environment September 6–11, 2005 Zakopane, Poland ECCTAE 2005 Selected Papers

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Introduction Being a reliable analysis method for the determination of caloric effects, power compensated differential scanning calorimetry (DSC) was applied to determine the heat of reaction of hydrothermal carbonization (HTC

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to its complexity. As the oxidation proceeds, several reactions occur simultaneously at different rates. These reactions release heat that can be measured using differential scanning calorimetry (DSC). Recording the heat released from a particular

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Journal of Thermal Analysis and Calorimetry
Authors: Christelle Herman, Tom Leyssens, Valérie Vermylen, Véronique Halloin, and Benoît Haut

with metastable forms [ 2 ]. Differential Scanning Calorimetry (DSC) is commonly used to evaluate most of the thermal properties of solid states, such as melting temperatures and enthalpies or specific heat capacities [ 3 ]. Whilst recent

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Abstract  

This personal review focuses on two aspects. First, glass transition dynamics and hence also calorimetry is connected to dynamic heterogeneity. This results in an interplay of the corresponding dynamic length scales and length scales from structural heterogeneities in polymeric samples. Second, the complexity of the dynamic glass transition itself results in different effects of this interplay for different experimental observables. Hence the comparison of results from calorimetry with other relaxation methods gives important clues to an understanding of the complex glass transition phenomenon.

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Abstract  

The mathematical-physical equation concerning the process of calorimetry of electrode reactions was deduced, and the corresponding solutions were obtained respectively for the period of the electrochemical polarization and that of the natural cooling. The calorimetry of the anodic oxidation of ferrocyanide to ferricyanide under linear sweep-current polarization was carried out, the obtained apparent enthalpy change of the electrode reaction agreed well with that obtained by the calorimetry with constant currents. The developed calorimetry with linear sweep-current and the data processing method are applicable for quick determination of apparent enthalpy changes of electrode reactions.

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Abstract  

October 2–5, 2005 Congress Center ACADEMIA Star Lesn, Slovak Republic Guest Editor: Peter Šimon Organizers — Slovak Group of Thermal Analysis and Calorimetry Slovak Society of Chemistry Faculty of Technology and Food Technology, Slovak University of Technology Slovak Silicate Society Selected Papers

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Abstract  

Reading and co-workers introduced a new technique a few years ago called Modulated Differential Scanning Calorimetry or MDSC. Here the first part of a theoretical analysis for this technique is given. A simple mathematical model for modulated differential scanning calorimetry in the form of an ordinary differential equation is derived. The model is analysed to find the effect of a kinetic event in the form of a chemical reaction. Some possible sources of error are discussed. A more sophisticated version of the model allowing for spatial variation in a calorimeter is developed and it is seen how it can be reduced to the earlier model. Some preliminary work on a phase change is also presented.

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Abstract  

This article is a review of some of the results we have obtained by studying various kinds of emulsions using techniques from the simplest one, a home-made differential thermal analysis to elaborated ones such as differential scanning calorimetry commercial devices. These techniques were used not only to determine energetic values but also essentially to show and quantify physical chemical phenomena such as undercooling, freezing, melting, mass transfer between droplets and solid formation involved in hydrate formation.

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Abstract  

Semi-batch reactors are widely spread in the fine chemicals and specialties industry. The reason is that, compared to the pure batch operation, the feed of at least one of the reactants provides an additional way of controlling the reaction course, which represents a safety factor and increases the constancy of the product quality. Process temperature and feed rate can be optimized to satisfy safety constraints, i.e. cooling capacity and allowable accumulation. An economically better way of operating a semi-batch reactor is to adapt the feed rate to the allowed accumulation of reactants. An experimental method based on calorimetry will be presented and illustrated by an example.

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