Calorimetric Measurement of the Enthalpy of Hydration of Clinoptilolite

The parallel nano-scanning calorimeter (PnSC) is a silicon-based micromachined device for calorimetric measurement of nanoscale materials in a high-throughput methodology. The device contains an array of nanocalorimeters. Each nanocalorimeter consists of a silicon nitride membrane and a tungsten heating element that also serves as a temperature gauge. The small mass of the individual nanocalorimeters enables measurements on samples as small as a few hundred nanograms at heating rates up to 104 K/s. The sensitivity of the device is demonstrated through the analysis of the melting transformation of a 25-nm indium film. To demonstrate the combinatorial capabilities, the device is used to analyze a Ni–Ti–Zr sample library. The as-deposited amorphous samples are crystallized by local heating in a process that lasts just tens of milliseconds. The martensite–austenite transformation in the Ni–Ti–Zr shape memory alloy system is analyzed and the dependence of transformation temperature and specific heat on composition is revealed.

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Calorimetric measurement of the intermetallic compounds Cr3Ga and CrGa4 and thermodynamic assessment of the (Cr–Ga) system

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2005.01.026 ◽

2005 ◽

Vol 397 (1-2) ◽

pp. 155-160 ◽

Cited By ~ 14

Author(s):

A. Belgacem-Bouzida ◽

Y. Djaballah ◽

M. Notin

Keyword(s):

Intermetallic Compounds ◽

Thermodynamic Assessment ◽

Calorimetric Measurement

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Shelf-life prediction from induction period calorimetric measurements on materials undergoing autocatalytic decomposition

Canadian Journal of Chemistry ◽

10.1139/v90-321 ◽

1990 ◽

Vol 68 (11) ◽

pp. 2111-2114 ◽

Cited By ~ 26

Author(s):

Lee D. Hansen ◽

Delbert J. Eatough ◽

Edwin A. Lewis ◽

Robert G. Bergstrom ◽

Damaris Degraft-Johnson ◽

...

Keyword(s):

Shelf Life ◽

Induction Period ◽

Heat Generation ◽

Life Prediction ◽

Autocatalytic Reaction ◽

Calorimetric Measurement ◽

Autocatalytic Decomposition ◽

Calorimetric Measurements ◽

Shelf Life Prediction ◽

Degradation Reaction

The shelf- or use-life of a material which decomposes by an autocatalytic reaction is shown to be inversely proportional to the rate of heat generation during the induction period of the degradation reaction. Calorimetric measurement of the rate of heat generation during the induction period takes only a few hours. It can often be done at or very near the actual storage or use temperature of the material. Measurements on Lovastatin (2-methylbutanoic acid 1,2,3,7,8,8a-hexahydro-3,7-dimethyl-8-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1-naphthalenylester) are used as an example of this application. Keywords: autocatalytic, calorimetry, oxidation, decomposition, Lovastatin, Mevacor.

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