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Operational issues in isothermal calorimetry

Wadsö, Lars LU (2010) In Cement and Concrete Research 40(7). p.1129-1137
Abstract
Isothermal (heat conduction) calorimetry is a general technique to study processes through the thermal power they produce. This paper deals with operational issues concerning isothermal calorimeters. In this paper it is shown that steady-state and pulse calibrations give the same result; that the use of mobile heaters (placed in the reaction ampoule) give more accurate results than fixed heaters (placed in the ampoule holder); and that at least the tested calorimeter had calibration coefficients that were independent of the thermal power level. It is shown that well balanced references are necessary to get low noise and low drifts. It is discussed how baselines should be measured. The influence of temperature and sample size is also... (More)
Isothermal (heat conduction) calorimetry is a general technique to study processes through the thermal power they produce. This paper deals with operational issues concerning isothermal calorimeters. In this paper it is shown that steady-state and pulse calibrations give the same result; that the use of mobile heaters (placed in the reaction ampoule) give more accurate results than fixed heaters (placed in the ampoule holder); and that at least the tested calorimeter had calibration coefficients that were independent of the thermal power level. It is shown that well balanced references are necessary to get low noise and low drifts. It is discussed how baselines should be measured. The influence of temperature and sample size is also discussed and it is shown that large cement paste samples with high thermal powers will show an accelerated reaction. Finally, the thermal dynamics of a heat conduction calorimeter is discussed. (C) 2010 Elsevier Ltd. All rights reserved. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Time constants, Baselines, Calorimetry, Calibration, References
in
Cement and Concrete Research
volume
40
issue
7
pages
1129 - 1137
publisher
Elsevier
external identifiers
  • wos:000279095700016
  • scopus:77953326348
ISSN
0008-8846
DOI
10.1016/j.cemconres.2010.03.017
language
English
LU publication?
yes
id
623f3e63-0b64-4b80-bdb8-860b526b8b01 (old id 1630227)
date added to LUP
2010-07-23 13:10:23
date last changed
2018-07-08 03:33:27
@article{623f3e63-0b64-4b80-bdb8-860b526b8b01,
  abstract     = {Isothermal (heat conduction) calorimetry is a general technique to study processes through the thermal power they produce. This paper deals with operational issues concerning isothermal calorimeters. In this paper it is shown that steady-state and pulse calibrations give the same result; that the use of mobile heaters (placed in the reaction ampoule) give more accurate results than fixed heaters (placed in the ampoule holder); and that at least the tested calorimeter had calibration coefficients that were independent of the thermal power level. It is shown that well balanced references are necessary to get low noise and low drifts. It is discussed how baselines should be measured. The influence of temperature and sample size is also discussed and it is shown that large cement paste samples with high thermal powers will show an accelerated reaction. Finally, the thermal dynamics of a heat conduction calorimeter is discussed. (C) 2010 Elsevier Ltd. All rights reserved.},
  author       = {Wadsö, Lars},
  issn         = {0008-8846},
  keyword      = {Time constants,Baselines,Calorimetry,Calibration,References},
  language     = {eng},
  number       = {7},
  pages        = {1129--1137},
  publisher    = {Elsevier},
  series       = {Cement and Concrete Research},
  title        = {Operational issues in isothermal calorimetry},
  url          = {http://dx.doi.org/10.1016/j.cemconres.2010.03.017},
  volume       = {40},
  year         = {2010},
}