Equilibrium desorption isotherms of water,ethanol, ethyl acetate,and toluene on a sodium smectite clay

Desorption isotherms for water, ethanol, ethyl acetate and toluene from a sodium smectite clay have been determined by both dynamic vapor sorption (DVS) measurements and Knudsen thermogravimetry (KTGA), at the exception of toluene that was measured only by the DVS method. The results obtained using these two methods were in satisfactory agreement, providing reliable insight into the desorption process, with certain lack of precision for ethyl acetate. The observed desorption behaviour suggests a liquid like phase at high volatile load, and a sorbed state in which molecules interact with the counter ions, at low volatile contents. However, the isotherms for water determined at various temperatures nearly superposed when plotted as a function of water activity, indicating the strength of the interactions in the clay–water system to remain of the same order of magnitude as that in bulk water, consistent with previous ab initio calculations.     

Excited states and terminating bands in123,124I

High spin states in^123,124I were populated via the¹¹⁶Cd(¹¹B,xn) reaction at 38 MeV bombarding energy and via the¹¹⁰Pd(¹⁸O,pxn) reaction at 75 MeV energy. γ-ray energies, intensities, γγ coincidences and DCO ratios were measured with the GASP spectrometer. The level schemes were extended considerably. Band terminations were observed in both nuclei. In¹²³I the rotational band, which is built on the πh _11/2 single-particle state was extended to spinI ^π=(35/2)^?; at higher spin the level spacings and the feeding pattern were found to become irregular, indicating a structure change. The (39/2)^? state and the higher-lying (43/2)^? level were interpreted as aligned oblate states. In¹²⁴I a decoupled band was found to terminate in the same spin region. Total Routhian surface calculations were performed which support the occurrence of a band termination.     

Study of superdeformed bands in nuclei withA ∼ 150 by heavy-ion-γ coincidences

Superdeformed (SD) bands in¹⁵²Dy,¹⁵¹Dy and¹⁵¹Tb have been populated via the 5n, 6n and 5np evaporation channels, respectively, with the³³S+¹²⁴Sn reaction at 160 and 170 MeV bombarding energies. Population intensities are in good agreement with existing data for SD bands in^{151, 152}Dy and SD yrast band in¹⁵¹Tb. The excited twin SD band in¹⁵¹Tb with the same-transitions as the band in¹⁵²Dy is populated about 5 times more strongly than by the 6n evaporation channel. This might be explained in terms of competition between proton and emission out of an intermediate, excited superdeformed configuration of¹⁵²Dy.Dedicated to Prof. Dr. P. Kienle on the occasion of his 60th birthday