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Abstract  

A new calorimeter for measuring thermal conductivity of liquids has been constructed. It is wholly automatic under the computer control. The time of measurement is 1 s and the temperature rise due to heating is within 1°C. Six organic liquids and six aqueous solutions of electrolytes were employed as reference standards. The instrument was calibrated at 25°C. Its accuracy is better then 1% with a precision of about 0.2%.

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Abstract  

The present study introduces a volumetric heat and mass source model to investigate the flow field inside the hood and duct system and optimize the sampling technique in a large scale fire calorimeter. The model was validated using experimental measurements of the oxygen depletion factor, gas temperature and heat release rate. The calculated heat release rates determined using the CFD model were in good agreement with the experiments with the maximum discrepancy between the simulations and experiments being less than 5%. A series of CFD simulations were performed to examine the effects of sampling location, and the number of sampling points on the uncertainty of the heat release calculation. Detailed flow characteristics were analyzed to understand the complicated internal duct flow.

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Instrumentation and calibration of the Calvet calorimeter

Enthalpy of solution of PrBr3 at standard conditions

Journal of Thermal Analysis and Calorimetry
Authors: Beata Salamon, Jan Kapała, and Marcelle Gaune-Escard

height) [ 1 ] contains two cavities for one thermopile each and is surrounded by kanthal resistance and kaowool acting as a thermal insulation. Each thermopile is located in a cylindrical bottom-closed tube, a so-called “calorimeter cell” of thin

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Abstract  

In this paper, several small-scale screening test methods were discussed on evaluating the thermal hazard of reactive substances. Generally the sensitivities of DSC and ARC are not high enough to evaluate the thermal hazards for all reactive substance, especially, for those of complex reactions containing a phase and/or chemical reaction mechanism change in the lower temperature range. Using the C80, however, the reaction can easily be detected in the lower temperature range due to its high sensitivity. Therefore, the C80 gives generally more accurate results than DSC and ARC. Data from C80 and Dewar vessel were compared and it indicates that the Dewar vessel has also high enough sensitivity to evaluate the thermal hazard and determine the heat flux in lower temperature range of reactive substances.

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Abstract  

Classification based on thermal properties and temperature conditions of heat transfer between proper calorimeter andsurrondings was presented. The dynamic properties of distinguished groups of calorimeters were determined.

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Introduction Calorimeters were originally constructed for the measurement of specific heat capacity, and this application remained the most frequent hitherto [ 1 , 2 ]. Their current usage is, however, much wider. The enthalpy

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Modulated capillary titration calorimeter

Theoretical and experimental studies

Journal of Thermal Analysis and Calorimetry
Authors: G. Kotelnikov, S. Moiseyeva, and E. Mezhburd

Abstract  

A modulated capillary titration calorimeter has been developed. New software and optimization of the calorimetric unit CTD2156 are used as a basis of the modulated capillary titration calorimeter. The scanning mode of the calorimeter has been theoretically substantiated. The scanning of chambers temperature is provided due to the fact that the shield temperature is linearly varied at heating and cooling. The reversing and kinetic part of the total heat flow are measured at heating of a diluted collagen solution. The main advantage of the calorimeter is its ability to operate in a modulation mode, in an isothermal mode, in modes of linear heating and cooling of homogeneous and dispersoid liquid samples at an effective mixing of reagents in calorimetric chambers.

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Adsorption micro calorimeter

Design and electric calibration

Journal of Thermal Analysis and Calorimetry
Authors: V. García-Cuello, J. Moreno-Pirajan, L. Giraldo-Gutiérrez, K. Sapag, and G. Zgrablich

Abstract  

In this work, it is described an innovative heat flux micro calorimeter Tian-Calvet type designed to measure adsorption heats and reactions as well as adsorption isotherms. It consists in an adsorption instrument for volumetric gases, which is coupled to the micro calorimeter. The changes in the pressure are monitored by means of high sensitivity and high precision pressure transducers. The micro calorimeter has thermo elements that work by a Seebeck effect, in a twin cells system. The cells are inside a box in which the temperature can be adjusted from 77 to 300 K. The sensitiveness of the calorimeter is established by applying a perfectly known electric work. The results corresponding to the electric calibration, the base line stability determination and the time constant in the equipment are shown.

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Introduction Differential scanning calorimetry is an established technique for characterising the thermal properties of materials. Experiments involving a differential scanning calorimeter (DSC) generally involve the use of

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