Results 251 to 260 of about 41,926 (292)

Micromechanical thermogravimetry

Chemical Physics Letters, 1998
We demonstrate a new method for thermal analysis of nanogram quantities of material using a micromechanical thermogravimetric technique. The cantilever-type device uses an integrated piezoresistor to sense bending and simultaneously to ramp the temperature and control temperature cycles. It has a mass resolution in the picogram range.
Berger, R., Lang, H. P., Gerber, C., Gimzewski, J. K., Fabian, J. H., Scandella, L., Meyer, E., Guntherodt, H. J.   +7 more
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High resolution thermogravimetry

Journal of Thermal Analysis, 1992
A new thermogravimetric instrument is introduced, Hi-ResTM TGA 2950. The Hi-ResTM TQA gives a significant improvement to TG results. The instrument control parameters are varied as a function of the sample's rate of weight change. This novel feature improves resolution and reduces analysis time.
P. S. Gill, S. R. Sauerbrunn, B. S. Crowe   +2 more
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Precision thermogravimetry

Journal of Thermal Analysis and Calorimetry, 2015
Sources of inaccuracies in thermogravimetry and the ways of minimizing them are described. The disturbances related to buoyancy forces and disturbances caused by drag forces from local gas circulations have been studied and interpreted. Procedures leading to parts-per-million precision have been tested and proven. Recommendations for handling corrosive
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The kinetics of thermogravimetry

European Polymer Journal, 1970
Abstract Homogeneous degradation reactions are discussed with reference to thermogravimetric equations. The dimensional inadequacy of most of the previously-used equations is pointed out and rectified. The modified weight integral of the integrated rate equation is calculated for various reaction orders.
J.R. MacCallum, J. Tanner
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Reference materials for thermogravimetry

Journal of Thermal Analysis, 1981
The thermobalances available commercially have a wide range of heater-sample-temperature sensor relationships. Because of the differences, relating data from one apparatus to another has been imprecise. The International Confederation for Thermal Analysis has certified a set of magnetic reference materials for thermogravimetry.
Paul D. Garn, O. Menis, H. G. Wiedemann
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Rate Equations in Thermogravimetry

Nature, 1970
MacCallum and Tanner1 have argued persuasively for modifying the rate equations used in thermogravimetry, but their conclusions are incorrect. There is no fundamental error of the kind they suggest in the usually accepted procedures and some other reason must be found for discrepancies in derived kinetic parameters.
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Thermal standards in thermogravimetry

Talanta, 1967
Comparisons of thermogravimetric data from different instruments have often led to controversy because of lack of appreciation that the values are influenced by the apparatus used. Consequently, it is suggested that various compounds be employed as thermal standards for comparing data from different sources. The paper also discusses the variables to be
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Temperature Measurement in Thermogravimetry

Review of Scientific Instruments, 1964
A method is described whereby the temperature of a sample in a thermobalance may be determined directly without the large uncertainty that usually accompanies these measurements. The procedure consists of using a unijunction transistor relaxation oscillator with a thermistor as the resistive part.
Emanuel P. Manche, Benjamin Carroll
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Coal analysis using thermogravimetry

Thermochimica Acta, 1984
Thermogravimetric analysis is being used increasingly today to obtain kinetic data related to coal decomposition. However, this method is open to criticism on the basis that the meaning of the activation energy of solid state reactions obtained from TG experiments is not clear.
M.A. Serageldin, Wei-Ping Pan
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Nonisothermal thermogravimetry of polymers

Journal of Thermal Analysis, 1995
The model of weight loss taking place in each step of a scheme of consecutive reactions was applied to nonisothermal thermogravimetric records of bromomethylated poly(2,6-dimethyl-1,4-phenylene oxide). The release of HBr was found to be faster in air than in nitrogen.
J. Líška, J. Rychly, E. Borsig
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