Dynamic Control of Nanoprecipitation in a Nanopipette

Studying the earliest stages of precipitation at the nanoscale is technically challenging but quite valuable as such phenomena reflect important processes such as crystallization and biomineralization. Using a quartz nanopipette as a nanoreactor, we induced precipitation of an insoluble salt to generate oscillating current blockades. The reversible process can be used to measure both kinetics of precipitation and relative size of the resulting nanoparticles. Counter ions for the highly water-insoluble salt zinc phosphate were separated by the pore of a nanopipette and a potential applied to cause ion migration to the interface. By analyzing the kinetics of pore blockage, two distinct mechanisms were identified: a slower process due to precipitation from solution, and a faster process attributed to voltage-driven migration of a trapped precipitate. We discuss the potential of these techniques in studying precipitation dynamics, trapping particles within a nanoreactor, and electrical sensors based on nanoprecipitation

Nanopore surface coating delivers nanopore size and shape through conductance-based sizing

The performance of nanopore single-molecule sensing elements depends intimately on their physical dimensions and surface chemical properties. These factors underpin the dependence of the nanopore ionic conductance on electrolyte concentration, yet the measured, or modeled, dependence only partially illuminates the details of geometry and surface chemistry. Using the electrolyte-dependent conductance data before and after selective surface functionalization of solid-state nanopores, however, introduces more degrees of freedom and improves the performance of conductance-based nanopore characterizations. Sets of representative nanopore profiles were used to generate conductance data, and the nanopore shape and exact dimensions were identified, through conductance alone, by orders-of-magnitude 3 reductions in the geometry optimization metrics. The optimization framework could similarly be used to evaluate the nanopore surface coating thickness

Platform camera aircraft detection for approach evaluation and training

Approach training currently relies solely on manual observation of and verbal feedback to the pilot. This project aims to provide both pilots and landing signal officers (LSOs) with valuable information about individual approaches in the carrier landing environment. The author investigated fully automatic flight path acquisition by means of computer vision-based analyses of platform camera video. The obtained data supports enhanced LSO training, real-time approach analysis and pilot self-improvement through advanced review capabilities.http://archive.org/details/platformcamerair109453612US Navy (USN) author.Approved for public release; distribution is unlimited