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Abstract  

Thermal analysis combined with mass spectrometry was applied to radiocarbon dating procedures (age determination of carbon-containing samples). Experiments carried out under an oxygen atmosphere were used to determine carbon content and combustion range of soil and wood samples. Composition of the shell sample and its decomposition were investigated. The quantification of CO2 formed by the oxidation of carbon was done by the application of pulse thermal analysis. Experiments carried out under an inert atmosphere determined the combustion range of coal with CuO as an oxygen source. To eliminate a possible source of contamination in the radiocarbon dating procedures the adsorption of CO2 by CuO was investigated.

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Abstract  

Thermal analysis combined with mass spectrometry was applied to radiocarbon dating procedures (age determination of carbon containing samples) to determine the optimal temperature range for the reduction of CO2 over metallic cobalt of various particle sizes. Experiments were carried out to show the different catalytic activities of cobalt of particle sizes 1, 1–45 and 44 m. The morphology of the cobalt samples and the deposited carbon were investigated. The quantification of CH4 and CO formed during the reduction of CO2 was done by means of pulse thermal analysis.

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Abstract  

This article presents results of the experimental investigation on the adsorption of the water vapor on silica gel. Two independent experimental methods has been used, viz. the constant-volume-variable-pressure (CVVP) system and variable pressure thermogravimetry (TG). Results from these two methods are compared with each other. Also the isosteric heat of adsorption of this system has been determined from the equilibrium data. The silica gels investigated here are Fuji Davison type 'A' and type 'RD'. Adsorption isotherm of water vapor have been measured under a variety of conditions all referring to chiller operation cycles, i.e. temperatures from 303 to 358 K and pressures from 500 to 7000 Pa. The data collected from the two independent experiments compare very favorably with each other and their trends are consistent with those of the adsorption chiller manufacturer. This lends significant weight to our experimental data on silica gel+water systems as being valuable to the adsorption chiller manufacturers and the scientific community.

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