Slow Oscillations of a Rotational Pendulum

MEASUREMENT OF PURE GAS ADSORPTION EQUILIBRIA (N=l) BY SLOW OSCILLATIONS OF A ROTATIONAL PENDULUM 

The instrument meanwhile has been transferred to the Institute of Thermodynamics, Dept. Chem. Engineering, University ofDortmund, Dortmund (2003). 

Rotational pendulum for measurements of gas adsorption equilibria by observing slow damped oscillations. Height of instrument 1.5 m. More parameters of the instrument are given in Sect. 2.4. 

For the instrument shown in Figs. 5.1, 5.2 we could observe for various gases at different pressures rotational oscillations for up to 30 minutes having oscillation times of about (30 5) seconds and logarithmic decrements of about 10 , cp. Sect. 2.2. For choice of materials and design information, hints already given in the foregoing chapters should be observed. Details can also be found in [5.2, 5.7, 5.11-5.13]. Here we point out that 

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Abstract The physical and experimental technique of gas adsorption measurements by slow oscillations of a rotational pendulum or, hkewise, the relaxational motion of a freely floating rotator are described. Combinations of the pendulum with either gravimetric or volumetric measurements are outhned. These especially are suited to measure the absorption or solubility of gases in non-rigid or swelling sorbent materials like polymers. Pros and cons of these methods are discussed in brief. List of symbols. References. 

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