Setting benchmarks for modelling gas–surface interactions using coherent control of rotational orientation states

A fundamental and predictive understanding of molecule-surface interactions is challenging to obtain. Here the authors report an experimental technique allowing direct measurement of the scattering matrix, which reports on the coherent evolution of quantum states of a molecule scattering from a surface

Fraunhofer-Institut fuer Betriebsfestigkeit (LBF) Darmstadt. Taetigkeitsbericht 1991

SIGLEAvailable from TIB Hannover: ZO 1192(1991) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Fraunhofer-Institut für Betriebsfestigkeit. Tätigkeitsbericht 1994

The annual report 1994 of the Fraunhofer-Institute for Strength of Structures under Operational Conditions comprises information on the objectives and organization of the institute as well as on the competence and services provided including lists of project files, publications, lectures and other activities in 1994. Four project reports serve as examples to characterize the typical approaches the institute is offering in more detail: H. Oppermann discusses in his contribution "Improvement of the accuracy of analytical life prediction for metal components considering loading sequence effects" the influence of the order of load events on the fatigue process. As a result, characteristic functions - depending on the shape of specimen and load - are derived and integrated into an existing procedure for life prediction. Subject of the paper "Static and dynamic behavior of elastomer components under large deformations" by U.-J. Görke are various phenomena which are typical for elastomers, th e experimental identification of material parameters for appropriate material models and their implementation in finite element codes. A life prediction method is briefly outlined based on a combination of experimental results of test specimens under oscillating loads and finite element calculations. G. Fischer and V. Grubisic deal with a procedure to derive artificial load sequences based on service measurements of commercial vehicles. These loads are used in a test rig to simulate realistic stresses and strains in the air bellow of pneumatic suspension systems. Finally, H. Kaufmann and C. M. Sonsino in a contribution "Accuracy of life prediction of a steering knuckle based on a local stress concept" discuss divergent results of numerical life time predictions of a real steering knuckle under operational loading, using several state-of-the-art procedures based on results from specimens testing. None of the 6 investigated methods led to a sufficient quality of the prediction, so that t he authors recommend to apply those methods only for predimensioning purposes and to carry out experiments, if heavy oversizing has to be avoided

Schwingfestigkeit von Al_2O_3- und Si_3N_4-Keramiken

Various Al_2O_3 ceramics and random samples of two Si_3N_4 ceramics were examined, with all specimens differing in terms of material and manufacturing parameters. Of the Al_2O_3 ceramics, randomly selected specimens were tested for their banding strength at room temperature, and three specifically selected specimens were tested for their compressive strength at room temperature, at 800 C and at 1200 C. A number of specimen variants were examined by cyclic fatigue tests at room temperature and 800 C, and at 1200 C in one case, the specimens used being slightly notched specimens (#alpha#_n = 1,02 and 1,08), or more heavily notched speciments (#alpha#_n = 1.77, 1.90 and 2.24), with bending loads being either cyclic or growing. The Si_3N_4 specimens were randomly chosen for bending tests and cyclic fatigue tests, at room temperature. (orig./MM)Es wurden verschiedene Al_2O_3-Keramiken sowie stichprobenartig zwei Si_3N_4-Keramiken untersucht, die sich hinsichtlich ihrer Stoff- und Fertigungsparameter unterschieden. Fuer alle Al_2O_3-Keramiken wurden unter Raumtemperatur stichprobenartig Biegebruchfestigkeiten und fuer drei ausgesuchte Varianten Druckfestigkeiten unter Raumtemperatur, 800 und 1200 C ermittelt. Mit mehreren Varianten wurden unter Raumtemperatur, 800 C und in einem Fall unter 1200 C Schwingfestigkeitsversuche durchgefuehrt, und zwar mit leicht gekerbten (#alpha#_k_b = 1,02 und 1,08) und staerker gekerbten (#alpha#_k_b = 1,77, 1,90 und 2,24) Proben unter wechselnder und teilweise schwellender Biegebelastung. Mit den Si_3N_4-Varianten wurden nur stichprobenartig unter Raumtemperatur Biegebruch- und Schwingfestigkeitsversuche angesetzt. (orig./MM)SIGLEAvailable from TIB Hannover: RA 732(195) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Fraunhofer Institut fuer Betriebsfestigkeit. Leistungen und Ergebnisse. Jahresbericht 1997

Available from TIB Hannover: ZO 1192(1997) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman