Simulation of gaseous core nuclear rocket mixing characteristics using cold and arc heated flows

Mixing phenomena of cold and arc heated jets from coaxial flows of helium or nitrogen related to gaseous core nuclear rocket

'Leaves and Eats Shoots': Direct Terrestrial Feeding Can Supplement Invasive Red Swamp Crayfish in Times of Need

PMCID: PMC3411828This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Altitude performance of a low-noise-technology fan in a turbofan engine with and without a sound suppressing nacelle

Test variables were inlet Reynolds number index (0.2 to 0.5), flight Mach number (0.2 to 0.8), and flow distortion (tip radial and combined circumferential - tip radial patterns). Results are limited to fan bypass and overall engine performance. There were no discernible effects of Reynolds number on fan performance. Increasing flight Mach number shifted the fan operating line such that pressure ratio decreased and airflow increased. Inlet flow distortion lowered stall margin. For a Reynolds number index of 0.2 and flight Mach number of 0.54, the sound suppressing nacelle lowered fan efficiency three points and increased specific fuel consumption about 10 percent

Cardiovascular effects of calcium supplementation

Peer reviewedPostprin

In situ NMR and electrochemical quartz crystal microbalance techniques reveal the structure of the electrical double layer in supercapacitors.

Supercapacitors store charge through the electrosorption of ions on microporous electrodes. Despite major efforts to understand this phenomenon, a molecular-level picture of the electrical double layer in working devices is still lacking as few techniques can selectively observe the ionic species at the electrode/electrolyte interface. Here, we use in situ NMR to directly quantify the populations of anionic and cationic species within a working microporous carbon supercapacitor electrode. Our results show that charge storage mechanisms are different for positively and negatively polarized electrodes for the electrolyte tetraethylphosphonium tetrafluoroborate in acetonitrile; for positive polarization charging proceeds by exchange of the cations for anions, whereas for negative polarization, cation adsorption dominates. In situ electrochemical quartz crystal microbalance measurements support the NMR results and indicate that adsorbed ions are only partially solvated. These results provide new molecular-level insight, with the methodology offering exciting possibilities for the study of pore/ion size, desolvation and other effects on charge storage in supercapacitors

Modelling Human Locomotion

This report is a coverage of my 16 weeks practical training at the Center for Sensori-Motor Interaction of the Aalborg University (Denmark). One of their research topics is on the ?eld of the biomedical modelling, where they want to answer the question of the functional behavior of the proprioceptive feedback system of the human body. A valid/good biomedical model could support their hypotheses which are results from different measurements. The original intention of the project was to build a complete walking lower body model to ?nd the reason for proprioceptive feedback during walking. In the middle of the project this original goal was a too high, because of the additional work of redesigning previous work of Huber [26]. The goal is adjusted to design the mechanical and muscle model and a well documented report, so a next project can continue immediately. The mechanical and muscle model appeared to work correct and are veri?ed with measured data. The forward activation of the muscle/mechanical model is not completely the same as expected. This is because the used method does not take co-activation of antagonistic muscle into account. For the continuation of this project a complete measured data set is necessary, because the veri?cation is not 100% valid. This performed veri?cation uses data that is not correlated in the sense that is measured at the same conditions and persons

Southern Hemisphere atmospheric circulation response to the El Chichon and Pinatubo eruptions in coupled climate models

We study the response of the Southern Hemisphere circulation to the 1982 eruption of El Chichon and 1991 eruption of Pinatubo volcanoes in a suite of up-to-date coupled climate models.We find a significant response in austral spring and autumn in the years following the eruptions, which consists of a stronger stratospheric polar vortex and lowered sea-level pressure over the Antarctic, both consistent with the positive phase of the Southern Annular Mode. The seasonality of the response may be explained in terms of zonal flow�planetary wave interactions. This dynamical response is inconsistent with the observational reanalyses in the polar stratosphere in spring, but not in the troposphere where the internal variability is large compared to the magnitude of the response