Two challenges for improving the performance of air cathode, single-chamber microbial fuel cells (MFCs) include increasing Coulombic efficiency (CE) and decreasing internal resistance. Nonbiodegradable glass fiber separators between the two electrodes were shown to increase power and CE, compared to cloth separators (J-cloth) that were degraded over time. MFC tests were conducted using glass fi...

Microbial fuel cells (MFC) with 30% wet-proofed air cathodes have previously been optimized to have 4 diffusion layers (DLs) in order to limit oxygen transfer into the anode chamber and optimize performance. Newer MFC designs that allow close electrode spacing have a separator that can also reduce oxygen transfer into the anode chamber, and there are many types of carbon wet-proofed materials a...

A matroid M is said to be k–connected up to separators of size l if whenever A is (k − 1)–separating in M , then either |A| ≤ l or |E(M)− A| ≤ l. We use si(M) and co(M) to denote the simplification and cosimplification of the matroid M . We prove that if a 3–connected matroid M is 4–connected up to separators of size 5, then there is an element x of M such that either co(M\x) or si(M/x) is 3–co...

Introduction: Crosstalk is a leakage of X-ray or light produced in a matrix of X-ray detectors or array of photodiodes in one element to other elements affecting on image contrast and spatial resolution. In this study, we assessed X-ray crosstalk in a computed tomography (CT) scanner with small detector elements to estimate the effect of various parameters such as X-ray tube voltage, detector e...

The ideal battery separator would be infinitesimally thin, offer no resistance to ionic transport in electrolytes, provide infinite resistance to electronic conductivity for isolation of electrodes, be highly tortuous to prevent dendritic growths, and be inert to chemical reactions. Unfortunately, in the real world the ideal case does not exist. Real world separators are electronically insulati...

This study evaluated the separation efficiency and developed a pressure drop model for a multicyclone separator used for natural gas purification. The collection and grade efficiencies of a multicyclone separator with 15 single cyclone separators were evaluated at inlet velocities of 6–24 m/s and particle concentrations of 30–2000 mg/m at atmospheric pressure and room temperature. The experimen...

LetG be an r-outerplanar graph with n vertices. We provide a sequence of log(n)/(r+ 1) +8r separators in G, each containing a fixed number (at most 2r) of integerlabeled vertices and each separating the graph in a well-defined left and right side such that the following two conditions are fulfilled. (1) The separators are nested, meaning that the left side of every separator S is contained in a...

Direct borohydride fuel cells (DBFC), which operate on sodium borohydride (NaBH4) as the fuel, and hydrogen peroxide (H2O2) as the oxidant, are receiving increasing attention. This is due to their promising use as power sources for space and underwater applications, where air is not available and gas storage poses obvious problems. One key factor to improve the performance of DBFCs concerns the...