Applicability of 8OCB for temperature calibration of temperature modulated calorimeters

被引：21

作者：

Schick, C

Jonsson, U

Vassiliev, T

Minakov, A

Schawe, J

Scherrenberg, R

Lorinczy, D

机构：

[1] Univ Rostock, Dept Phys, D-18051 Rostock, Germany

[2] Umea Univ, S-90187 Umea, Sweden

[3] Bulgarian Acad Sci, Inst Phys Chem, BG-1113 Sofia, Bulgaria

[4] Moscow Gen Phys Inst, Moscow 117942, Russia

[5] IFA GmbH, D-89077 Ulm, Germany

[6] DSM Res BV, NL-6167 RA Geleen, Netherlands

[7] Univ Pecs, Sch Med, Dept Biophys, H-7643 Pecs, Hungary

来源：

THERMOCHIMICA ACTA | 2000年 / 347卷 / 1-2期

关键词：

temperature calibration; temperature modulated calorimetry; complex heat capacity; liquid crystal; phase transition;

D O I：

10.1016/S0040-6031(99)00416-5

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

Calibration of temperature modulated calorimeters (TMC) is essential because it is often not possible to calculate heat capacity and sample temperature directly from the quantities measured. The question arises whether temperature calibration used in conventional calorimetry is also valid for TMC's. To prove this, a well defined transition is needed which does not disturb the temperature profile within the sample during modulation. The response of the whole system (calorimeter, sample, transition) must be linear. Some low energy liquid crystal transitions behave in this way, under certain conditions, and can be used for temperature calibration in TMC's. The procedure is demonstrated for the nematic to smectic-A transition in a cyanobiphenyl liquid crystal (80CB). The applicability of 80CB for temperature calibration is shown for temperature modulated DSC, AC calorimeter, 3 omega method and photo-acoustic method. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：53 / 61

页数：9

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