Here we reported the investigation of enhanced performance for the removal of hexavalent chromium (Cr (VI)) by a new microbial fuel cell (MFC) with natural pyrrhotite-coated cathode. By comparisons of the graphite-cathode, the MFCs equipped with a pyrrhotite-coated cathode generated the maximum power density of 45.4 mW·m−2 that was 1.3 times higher than that of with bare graphite cathode (35.5 ...

Abstract An atmospheric-pressure dielectric barrier discharge (DBD) in argon is investigated using a time-dependent and spatially two-dimensional fluid-Poisson model axisymmetric geometry. The focus on the streamer–surface interaction cathode-layer formation during first event single-filament DBD driven by sinusoidal voltage. A characteristic structure consisting of volume streamer propagating ...

Atmospheric propagation experiments at the Air Force Weapons Laboratory utilize a 150 KA, 6 MV relativistic electron beam produced by field emission in a foil diode. To characterize the beam for the experiments requires an understanding of beam formation in the diode. To this end CCUBE, a sophisticated two-dimensional, time dependent, particle-in-cell code developed at Los Alamos National Labor...

A general model is presented for electron emission yield from planar photocathodes that accounts for arbitrary cathode thickness and finite recombination velocities at both front and back surfaces. This treatment is applicable to negative electron affinity emitters as well as positive electron affinity cathodes, which have been predicted to be useful for energy conversion. The emission model is...

Thermionic emission in heterostructures is investigated for integrated cooling of high power electronic and optoelectronic devices. This evaporative cooling is achieved by selective emission of hot electrons over a barrier layer from the cathode to the anode. As the energy distribution of emitted electrons is almost exclusively on one side of Fermi energy, upon the current flow, strong carrier-...

The Schottky electron emitter is the most frequently used electron source in electron microscopes. A suppressor electrode around the emitter is usually employed to prevent emission from the shank of the cathode. A concept of operating the Schottky emitter without the suppressor electrode is proposed with the aim of lowering the potential of the extractor electrode. Simulation results show that ...