Kapitel 2: Perspektiven zur Analyse und Gestaltung von Strukturen für ein klimafreundliches Leben

Kapitel 2 systematisiert entlang von vier Perspektiven in den Sozialwissenschaften weit verbreitete Theorien zur Analyse und Gestaltung von Strukturen klimafreundlichen Lebens. Das Kapitel möchte Leser_innen des Berichts bewusst machen, mit wie grundlegend unterschiedlichen Zugängen Forscher_innen Strukturen klimafreundlichen Lebens analysieren. Dies ist wichtig, um zu verstehen, dass es nie nur eine, sondern immer mehrere Perspektiven auf Strukturen klimafreundlichen Lebens gibt. Dieses Bewusstsein hilft, die Komplexität der Sozialwissenschaften und damit die Komplexität der Aufgabe – Strukturen für ein klimafreundliches Leben zu gestalten – zu erfassen. Unterschiedliche Zugänge zu sehen, bedeutet auch, ein besseres Verständnis von konfligierenden Problemdiagnosen, Zielhorizonten und Gestaltungsoptionen zu entwickeln und – idealerweise – damit umgehen zu können

Isomerization and melting-like transition of size-selected water nonamers

The vibrational OH-stretch spectra of size-selected pure water (H2O)9 clusters, measured at two different temperatures, have been used to identify isomeric transitions. The broad, featureless high-temperature, liquid-like spectrum resembles that of water, while the structured low- temperature, solid- like spectrum differs appreciably from that of ice. Accompanying calculations suggest that the low-temperature spectra originate from two cube-like structures. The high temperature spectra appear to be above an isomeric transition to more open amorphous arrangements of fused three- to five- membered rings

Isomerization and melting-like transition of size-selected water nonamers

The vibrational OH-stretch spectra of size-selected pure water (H2O)9 clusters, measured at two different temperatures, have been used to identify isomeric transitions. The broad, featureless high-temperature, liquid-like spectrum resembles that of water, while the structured low- temperature, solid- like spectrum differs appreciably from that of ice. Accompanying calculations suggest that the low-temperature spectra originate from two cube-like structures. The high temperature spectra appear to be above an isomeric transition to more open amorphous arrangements of fused three- to five- membered rings

Untersuchung von Wasserclustern mit inelastischer Heliumstreuung und Infrarotspektroskopie

The scope of this work is the investigation of water clusters made by adiabatic expansion of steam through nozzles. In the first part of the work the clusters up to n=200 were investigated by inelastic helium atom scattering at thermal collision energies. It was possible to excite modes until app. 40 meV (320 cm"-"1) which were compared with calculations from other works. In addition the temperature of the clusters was estimated from negative energy transfers to be about 120 K. In the second part spectroscopic investigations on small clusters up to n=10 in the range of OH stretch motions (2800-3800 cm"-"1) were carried out. They revealed spectra with maxima which could be assigned to several types of coordination and phases of the water clusters. (orig.)107 refs.Available from TIB Hannover: RA 1396(2000,3) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Elastic and rotationally inelastic differential cross sections for He+H₂O collisions

Elastic and rotationally inelastic cross sections have been measured for He+H2O scattering at two collision energies, 66.3 and 99.0 meV, using the crossed molecular beam technique. The inelastic events are detected by time-of-flight analysis of the scattered He atoms. The data are converted to elastic differential cross sections and inelastic angular-dependent energy loss spectra in the center-of-mass system. They are compared with averaged, full close-coupling calculations of state-to-state cross sections for rotational excitation based on a newly calculated ab initio potential using symmetry- adapted perturbation theory. The agreement with the elastic differential cross sections is excellent. The energy loss spectra are reproduced satisfactorily and among the largest differential cross sections that contributed to the measurements are excitations around all three possible axes for ΔJ = 1 but a preference of the excitation around the in- plane C axis for ΔJ = 2 transitions. (C) 2002 American Institute of Physics

Elastic and rotationally inelastic differential cross sections for He+H2O collisions

Elastic and rotationally inelastic cross sections have been measured for He+H2O scattering at two collision energies, 66.3 and 99.0 meV, using the crossed molecular beam technique. The inelastic events are detected by time-of-flight analysis of the scattered He atoms. The data are converted to elastic differential cross sections and inelastic angular-dependent energy loss spectra in the center-of-mass system. They are compared with averaged, full close-coupling calculations of state-to-state cross sections for rotational excitation based on a newly calculated ab initio potential using symmetry- adapted perturbation theory. The agreement with the elastic differential cross sections is excellent. The energy loss spectra are reproduced satisfactorily and among the largest differential cross sections that contributed to the measurements are excitations around all three possible axes for ΔJ = 1 but a preference of the excitation around the in- plane C axis for ΔJ = 2 transitions. (C) 2002 American Institute of Physics