Survey of the effect of fill volume on the values for the enthalpy and rate constant derived from isothermal microcalorimetry: applications of a newly developed test reaction
O'Neill, M.A.A., Beezer, A.E., Deal, R.M., Morris, A.C., Mitchell, J.C., Orchard, J.A. and Connor, J.C. (2003) Survey of the effect of fill volume on the values for the enthalpy and rate constant derived from isothermal microcalorimetry: applications of a newly developed test reaction. Thermochimica Acta, 397 (1-2). pp. 163-169. ISSN 0040-6031Full text not available from this repository.
A recent paper has reported the results of an inter/intralaboratory study into a test and reference reaction for isothermal microcalorimeters, the imidazole catalysed hydrolysis of triacetin. The values derived were 2.8 x 10(-6)+/-9.7 x 10(-8) dm(3) mol(-1) s(-1) and -91.7+/-3 kJ mol(-1) for the rate constant and enthalpy, respectively. This paper reports the findings of an investigation, using this test reaction, into the effect of ampoule fill volume on the recovery of the derived rate constant and enthalpy. Fill volume is likely to be of significance for all commercially available, heat conduction, isothermal microcalorimeters. Experiments, reported here, were performed in a thermal activity monitor (TAM, thermometric AB, Jarfalla, Sweden) operating in the batch mode, for 3, 4 and 20 ml glass ampoules and 4 ml stainless steel ampoules. It is shown that the rate constant can be accurately recovered at fill volumes greater than 50% but below 50% fill volume this accuracy diminishes.
|Uncontrolled Keywords:||triacetin, volume study, isothermal microcalorimetry|
|Subjects:||Q Science > QD Chemistry|
R Medicine > RS Pharmacy and materia medica
|School / Department / Research Groups:||School of Science|
School of Science > Department of Pharmaceutical, Chemical & Environmental Sciences
|Last Modified:||26 Nov 2012 10:41|
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