A rectangular gridded ion thruster discharge chamber is investigated for operation with multiple discharge cathode assemblies. The multiple-cathode approach attempts to increase thruster throughput and lifetime by operating three discharge cathode assemblies sequentially, possibly providing a threefold increase in discharge chamber life. Previous multiple-cathode electric propulsion devices, su...

A microbial fuel cell (MFC) has been developed for removal of sulfur-based pollutants and can be used for simultaneous wastewater treatment and electricity generation. This fuel cell uses an activated carbon cloth+carbon fibre veil composite anode, air-breathing dual cathodes and the sulfate-reducing species Desulfovibrio desulfuricans. 1.16gdm(-3) sulfite and 0.97gdm(-3) thiosulfate were remov...

The fructose/dioxygen biofuel cell, one of the direct electron transfer (DET)-type bioelectrochemical devices, utilizes fructose dehydrogenase (FDH) on the anode and multi-copper oxidase such as bilirubin oxidase (BOD) on the cathode as catalysts. The power density in the literature is limited by the biocathode performance. We show that the DET-type biocathode performance is greatly improved, w...

Zn–air and other metal–air batteries suffer from limited shelf life due to carbonization by CO2 evaporation of water through the cathode. Bioinspired oxygen selective membranes (OSMs) with common similarities lungs alveoli were prepared applied as an passive membrane on cathode batteries, which limit H2O transport while actively supporting O2 flux. The OSMs polycarbonate iron(II) phthalocyanine...

We report a microstructure, which if electrified in a hydrogen peroxide solution covers its top with a thin layer of oxygen gas in a self-regulating manner. In pursuit of realizing a full fuel cell with no moving part, we have successfully developed such an oxygen-generating surface and integrated it as a direct oxygen supply to the cathode of our previously developed miniature fuel cells. The ...

The electrochemical oxidation behaviors of NaBH4 on Zn, Zn–MH, and MH (metal-hydride) electrodes were investigated, and an intrinsic direct orohydride fuel cell (DBFC)/battery hybrid power source using MH (or Zn–MH) as the anode and MnO2 as the cathode was tested. Borohydride annot be effectively oxidized on Zn electrodes at the Zn oxidation potential because of the poor electrocatalytic abilit...

A critical analysis of photoionization as the major process for seed electron production ahead of the cathode-directed streamer has been made. The accumulation of O2 ions between pulses and fast electron detachment in an electric field could be an effective source of seed electrons for repetitively pulsed discharges in electronegative gases. Measurements and two-dimensional calculations in the ...

We model heat dominated electrical breakdown in air in a short planar gap. We couple the discharge dynamics in fluid approximation with the hydrodynamic motion of the air heated by the discharge. To be computationally efficient, we derive a reduced model on the ion time scale, and we switch between the full model on the electron time scale and the reduced model. We observe an ion pulse reaching...

With the surge of interest in miniaturized implanted medical devices (IMDs), implantable power sources with small dimensions and biocompatibility are in high demand. Implanted battery/supercapacitor devices are commonly packaged within a case that occupies a large volume, making miniaturization difficult. In this study, we demonstrate a polymer electrolyte-enabled biocompatible magnesium-air ba...

This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. A specially modified version of the Traffic Alert and Collision Avoidance System (TCAS) was installed in a Bell Long Ranger helicopter in order to investigate the feasibility of TCAS op...