Integral Experiment Request 554 CED-1 Summary Report

Abstract

This Critical Engineering Decision 1 report for the Integral Experiment Request 554 describes the effects of adding a commercially available neutron absorber material to a known light-water low-enriched uranium assembly. The assembly in question is the Seven Percent Critical Experiments at Sandia National Laboratories. The neutron absorber plates considered for the experiment are called Boralcan, which are made of boron carbide (B 4 C) particles embedded in 1100 aluminum alloy. The concentrations of B 4 C and 1100 aluminum, as well as the thickness and size of the plates, were changed, and the fuel rod configuration was adapted to ensure that the assembly would be critical in each case studied. A total of 10 critical configurations with a neutron absorber plate inserted are described in this report. No results of high-quality integral experiments involving neutron absorbers made with B 4 C and 1100 aluminum plates are currently publicly available. Sensitivity to the neutron absorber plate material definition, isotopes, and cross sections of specific regions and configurations are also analyzed. The study results indicate that these experiments are achievable with sufficiently low uncertainties and minimal modification to the assembly. The experimental uncertainty can be further decreased with an additional characterization of the plates by x-ray computerized tomography or neutron radiography methods.

Piezoelectric materials and systems for tissue engineering and implantable energy harvesting devices for biomedical applications

“…Lead zirconium titanate (PZT) Lu et al [272] developed a flexible PZT-based system to harvest energy from cardiac contractions generated by the heart to power pacemakers which they tested in vivo on swine hearts. The device consisted of a commercial PZT wafer processed into nanoribbons (NRs) on a flexible polyimide -based film (Kapton® substrate) which has attractive dielectric properties such as low conductivity and dielectric loss across a wide range of temperatures [273][274][275] (Figure 17(a)). The resultant system was integrated into a swine heart in both the open and closed cavity of the specimen.…”