Dynamics of cathode spot has become a major part of vacuum arc discharge with its high academic interest and wide application potential. In this article, using a three-dimensional statistical model, we simulate the distribution of the ignition probability of a new cathode spot occurring in different magnetic pressure on old cathode spot surface and at different arcing time. This model for the i...

Presented are preliminary measurements of near-cathode ion velocity distributions using time-resolved laser induced fluorescence. Two experiments were performed. First, time-averaged velocity distributions were measured in a LaB6 hollow cathode plume under the influence of a Hall thruster magnetic field provided by the 6-kW H6 thruster. The discharge was sustained without a downstream anode but...

Low-work-function active metals are commonly used as cathode in polymer solar cells (PSCs), but sensitivity of the active metals towards moisture and oxygen results in poor stability of the devices. Therefore, solution-proceessable and stable cathode buffer layer is of great importance for the application of PSCs. Here we demonstrate high performance PSCs by employing as-prepared zirconium acet...

Conditioning of the insert inside a hollow cathode is believed to be important to ensure reliable discharge initiation and subsequent cathode operation. The desorption of contaminates is reported from hollow cathodes as a function of heater power to quantify cathode conditioning characteristics and identify factors that might prevent the fast initiation of a discharge. In addition to conditioni...

Oxygen-reducing biocathodes previously developed for microbial fuel cells (MFCs) have required energy-intensive aeration of the catholyte. To avoid the need for aeration, the ability of biocathodes to function with passive oxygen transfer was examined here using air cathode MFCs. Two-chamber, air cathode MFCs with biocathodes produced a maximum power density of 554 ± 0 mW/m(2), which was compar...

The application of a rotating cathode in a river sediment microbial fuel cell increased the oxygen availability to the cathode, and therefore improved the cathode reaction rate, resulting in a higher power production (49 mW/m(2)) compared to a nonrotating cathode system (29 mW/m(2)). The increased dissolved oxygen in the water of our lab-scale sediment MFC, however, resulted in a less negative ...

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 ...

There is interest in the use of carbon nanotubes (CNTs) to create a field emission cathode. The primary benefit of this cathode is that a gas flow is not required to create electrons, which is of critical importance for space missions that must minimize propellant mass. A field emission cathode consisting of CNT arrays is fabricated by the Georgia Tech Research Institute and the Georgia Tech Hi...

We present here measurements of plasma display panel PDP ignited by SrO and SrCaO cold cathodes with high yield of ion-induced secondary electron emission high i . SrOand SrCaO-cathode PDPs attain high luminous efficacy at low applied voltage, where the breakdown voltage is 30% lower than that of ordinary MgO-cathode PDP. Current and emission measurement clearly demonstrates that SrOand SrCaO-c...

Cathode spot motion influences the physical characteristics of arc plasma and the related macroparticles (MPs) in resultant films; these MPs limit the application of arc ion plating (AIP). In this paper, a scanning radial magnetic field (SRMF) was applied to the cathode surface to control the cathode spot motion and reduce the MP contamination in the deposited films. It was shown that film surf...