A New Ultrasonic Transducer Sample Cell for In Situ Scattering Experiments

摘要

Ultrasound irradiation is a commonly used technique for non-destructivediagnostics or targeted destruction. We report on a new versatile sonicationdevice that fits in a variety of standard sample environments for neutron andX-ray scattering instruments. A piezoelectric transducer permits measuring ofthe time-dependent response of the sample in situ during or after sonication.We use small-angle neutron scattering (SANS) to demonstrate the effect of atime-dependent perturbation on the structure factor of micelles formed fromsodium dodecyl sulfate (SDS) surfactant molecules. We observe a significantchange during and after sonication and a time-dependent relaxation to theequilibrium values of the unperturbed system. The strength of the perturbationof the structure factor depends systematically on the duration of sonication.The relaxation behavior can be well reproduced after multiple times ofsonication. Accumulation of the recorded intensities of the differentsonication cycles improves the signal-to-noise ratio and permits reaching veryshort relaxation times. Due to the flexibility of our new in situ sonicationdevice, different experiments can be performed, e.g. to explore molecularpotentials in more detail by introducing a systematic time-dependentperturbation.