A Model to Predict Percolation Threshold and Effective Conductivity of Infiltrated Electrodes for Solid Oxide Fuel Cells

We present a mechanistic modeling methodology to predict both the percolation threshold and effective conductivity of infiltrated Solid Oxide Fuel Cell (SOFC) electrodes. The model has been developed to mirror each step of the experimental fabrication process. The primary model output is the infiltrated electrode effective conductivity which provides results over a range of infiltrate loadings that are independent of the chosen electronically conducting material. The percolation threshold is utilized as a valuable output data point directly related to the effective conductivity to compare a wide range of input value choices. The predictive capability of the model is demonstrated by favorable comparison to two separate published experimental studies, one using strontium molybdate and one using La0.8Sr0.2FeO3-δ as infiltrate materials. Effective conductivities and percolation thresholds are shown for varied infiltrate particle size, pore size, and porosity with the infiltrate particle size having the largest impact on the results.

A Model to Predict Percolation Threshold and Effective Conductivity of Infiltrated Electrodes for Solid Oxide Fuel Cells

We present a mechanistic modeling methodology to predict both the percolation threshold and effective conductivity of infiltrated Solid Oxide Fuel Cell (SOFC) electrodes. The model has been developed to mirror each step of the experimental fabrication process. The primary model output is the infiltrated electrode effective conductivity which provides results over a range of infiltrate loadings that are independent of the chosen electronically conducting material. The percolation threshold is utilized as a valuable output data point directly related to the effective conductivity to compare a wide range of input value choices. The predictive capability of the model is demonstrated by favorable comparison to two separate published experimental studies, one using strontium molybdate and one using La0.8Sr0.2FeO3-delta as infiltrate materials. Effective conductivities and percolation thresholds are shown for varied infiltrate particle size, pore size, and porosity with the infiltrate particle size having the largest impact on the results. (C) 2013 The Electrochemical Society. All rights reserved.

Passage of Alabama's Hb 56: Fueled By Dominant Anti-Immigration Tropes

Abstract Background. In 2011, Alabama, neither a border state nor hold a significantly large Hispanic population, passed the most restrictive state immigration law, The Beason-Hammon Alabama Taxpayer and Citizen Protection Act, HB 56. This omnibus law was far-reaching in its restrictions, including, but not limited to, identification, public services, employment, housing, and law enforcement. Objectives. This research explores the dominant tropes present in the narrative surrounding the anti-immigration legislative activity in Alabama that created fertile ground for the passage of such a punitive immigration law. Methods. Newspaper articles from 2007 to 2011 in Alabama¿s Birmingham News and Press-Register, the two most circulated newspapers in the state, were attained from NewsLibrary.com, an online database of 5,311 newspapers and other news sources. Results. Seven dominant tropes were identified in the articles that pushed for anti-immigration policies. These tropes claimed (1) the US-Mexico border is not secure, (2) the federal government has failed to enact comprehensive immigration reform, (3) immigrants steal jobs, hurt the economy, and (4) burden public services, (5) immigrants are criminals and terrorists, (6) they refuse to assimilate and learn English, and (7) there has been a dramatic percent change in the Hispanic and illegal populations. These tropes cumulatively worked together to create anti-immigration sentiment that pushed for the passage of HB 56.