Anode Fabrication for Solid Oxide Fuel Cells: Electroless and Electrodeposition of Nickel and Silver into Doped Ceria Scaffolds

© 2016 The Authors.A novel fabrication method using electroless and electrodeposited Ni/Ag/GDC for SOFC anodes is presented. First a porous Ce0.9Gd0.1O2-x (GDC) scaffold was deposited on a YSZ electrolyte by screen printing and sintering. The scaffold was then metallized with silver using Tollens reaction, followed by electrodeposition of nickel from a Watts bath. The electrodes (Ni/Ag/GDC) were tested in both symmetrical and fuel cell configurations. The microstructures of the Ni/Ag/GDC anodes were analyzed using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX). Nano-particles of Ni formed in the porous GDC scaffold provided triple phase boundaries (TPB). The electronic conductivity of the Ni/Ag/GDC (3.5/24.7/71.8 vol%) electrode was good even at relatively low Ni volume fractions. The electrochemical performance was examined in different concentrations of humidified hydrogen (3% H2O) and over a range of temperatures (600-750 °C). The total area specific resistance (ASR) of the anode at 750 °C in humidified 97 vol% H2 was 1.12 Ω cm2, with low-frequency polarization (R-l) as the largest contributor. The electrodes were successfully integrated into a fuel cell and operated in both H2 and syngas

Transverse emittance dilution due to coupler kicks in linear accelerators

One of the main concerns in the design of low emittance linear accelerators (linacs) is the preservation of beam emittance. Here we discuss one possible source of emittance dilution, the coupler kick, due to transverse electromagnetic fields in the accelerating cavities of the linac caused by the power coupler geometry. In addition to emittance growth, the coupler kick also produces orbit distortions. It is common wisdom that emittance growth from coupler kicks can be strongly reduced by using two couplers per cavity mounted opposite each other or by having the couplers of successive cavities alternation from above to below the beam pipe so as to cancel each individual kick. We therefore analyze consequences of alternate coupler placements. We show here that for sufficiently large Q values, alternating the coupler location from before to after the cavity leads to a cancellation of the orbit distortion but not of the emittance growth, whereas alternating the coupler location from before and above to behind and below the cavity cancels the emittance growth but not the orbit distortion. These compensations hold even when each cavity is individually detuned, e.g. by microphonics. Another effective method for reducing coupler kicks that is studied is the optimization of the phase of the coupler kick. This technique is independent of the coupler geometry but relies on operating on crest. A final technique studied is symmetrization of the cavity geometry in the coupler region with the addition of a stub opposite the coupler, which reduces the amplitude of the off axis fields and is thus effective for off crest acceleration as well. We show applications of these techniques to the energy recovery linac (ERL) planned at Cornell University

A Europe of Regionalists: How Has European Integration Impacted Regionalist Political Parties’ Electoral Support?

This study investigates the question: How has European integration impacted regionalist political parties’ electoral support? European integration and regionalism are theoretically connected by Seth Jolly’s viability theory which explains that supranational organizations, such as the European Union (and precursor organizations), make small countries more viable. Using the regions of Flanders, Corsica, Sardinia, Padania, Galicia, and Catalonia as case studies, this thesis identifies moments of European integration and then examines if regionalist electoral results match the expectations of viability theory. This thesis found support for the idea that European integration is positively affecting regionalist political parties in elections; however, there often exists other contextual factors that can modify or negate this effect. European integration is just one of the many issues that regionalists must address, but, as this thesis shows, it is an issue that deserves their attention and, if used wisely, their support. I conclude the thesis by considering the implications of the viability theory for different decision-makers within the European Union and its member countries, and I explore how regionalism needs a solution from supranational organizations because, as more countries join and spend longer in supranational organizations, regionalism should be expected become more widespread

The Regulation of Skeletal Muscle Fatigue During the Progression of Cancer Cachexia

Cachexia is the unintentional loss of body weight secondary to chronic disease and is prevalent is roughly 50% of cancer patients. The loss of body weight and skeletal muscle mass is reduced functional capacity associated with reduced life quality. The etiology of cachexia is multimodal and complex; however, cachexia has been linked to several systemic (e.g. chronic inflammation, hypogonadism, anemia, insulin resistance) and behavioral (e.g. anorexia, inactivity) changes that can compound to accelerate muscle mass and body weight loss. While several inflammatory cytokines are associated with cachexia’s disease progression, our laboratory has established that Interleukin-6 (IL-6) is a key regulator of skeletal muscle mass maintenance in tumor-bearing ApcMin/+ (MIN) mice. Additionally, we have shown that reduced volitional activity and increased skeletal muscle fatigue occurs prior to significant wasting and exercise training is able to prevent IL-6- induced cachexia in the MIN without affecting muscle inflammatory signaling. Furthermore, repeated muscle contractions were able to attenuate myofibrillar atrophy, and increase muscle oxidative metabolism without effecting the tumor environment. While the efficacy of exercise to improve skeletal muscle’s metabolic health during aging and disease has been well described, the effects of volitional activity on cancer-induced skeletal muscle fatigue, oxidative metabolism, and muscle inflammatory signaling is not well understood. The overall purpose of this study is to determine the regulation of skeletal muscle fatigue by activity and muscle inflammatory signaling during the progression of cachexia. Our central hypothesis is that cancer-induced skeletal muscle fatigue develops prior to significant weight loss concomitant with decreased muscle use and disrupted muscle oxidative metabolism which occurs through chronically activated muscle gp130 signaling. Our results suggest that the onset of skeletal muscle fatigue developed prior to significant weight loss in MIN mice. Furthermore, elevated circulating IL-6 accelerated skeletal muscle fatigue and reduced muscle oxidative metabolism through muscle gp130 signaling; however, loss of muscle gp130 signaling was unable to improve skeletal muscle fatigue in MIN mice. Last, we demonstrate that there is a direct relationship between activity and skeletal muscle fatigability in healthy and tumor-bearing mice. Together, these results suggest that fatigue develops independent of weight loss and while elevated IL-6 contributes to skeletal muscle fatigue, cancer-induced fatigue was not solely regulated by IL-6/muscle gp130 signaling

The influence of anxiety, depression, and negative affect on recall of dental pain

Research suggests mood can influence recall of emotionally-relevant information. Yet, despite multiple studies examining the association of anxiety and exaggerated prediction and recall of dental pain, the influence of other moods on prediction and recall of dental pain remains poorly investigated. Further, the potential moderation and mediation effects for dental fear, fear of pain, and mood state have not been properly researched. The present study investigated variables associated with predicted pain (pain expected during the dental procedure) and recalled pain in oral surgery patients. Data were provided by a sample of 157 patients undergoing tooth extraction under local anesthetic. Patients completed measures of depression, anxiety, and negative affect both at the time of surgery and at a 1-month follow-up. Dental fear and fear of pain also were assessed prior to extraction. Path analysis was used to examine relations among variables, including mediation effects of mood state between dental fear or fear of pain and report of pain; moderation effects of dental fear and fear of pain on report of pain were examined using regression equations. The best fitting models suggested mood prior to extraction was related to current pain prior to extraction (beta = .18--.23), but not predicted or recalled pain. Dental fear, however, was related to predicted pain (beta = .25--.26). Predicted pain was associated with recalled pain and also influenced recalled pain through its relation with pain during extraction. In a final exploratory model, the influence of negative affect on current pain became non-significant when accounting for the influence of anxiety and depression. Additionally, fewer prior extractions and shorter duration of dental pain prior to extraction were associated with more predicted pain; greater chronic pain rating and injection of an additional anesthetic were related to more recalled pain. Dental fear proved a theoretically and clinically relevant construct in the oral surgery context, especially in relation to prediction of pain; reduction of dental fear may reduce aversive experiences and report of pain during dental procedures. Future research should clarify more specific relations between mood and pain over time, including patterns of change or stability

A Hip Hop Episteme: Understanding Hip Hop Culture’s Ways of Knowing and Expressing Knowledge through Time Travel and Traditional African and Afro-Diasporic Spirituality

Perhaps one of my earliest and most interesting Hip Hop experiences occurred early on in my childhood. I remember being in my mother’s bedroom, and I think the lights were off. And I was using my mother’s Sharp CD-C600 Mini Component System with the 3-CD Drawer Changer to play a CD copy of 50 Cent’s Get Rich or Die Tryin’ album that she had purchased for me. I remember being really excited to be playing my favorite song on the album, “In Da Club” (I used to pretend it was my birthday and that 50 Cent was rapping for me, and, as a child, I didn’t really grasp what he was talking about in the lyrics). The thing that makes this particular experience significant to me, though, was that I remember that the CD must have had a scratch on it because it would skip and start again right from the line in the chorus when 50 says “So come give me a hug”. I don’t remember whether or not I was disappointed to learn that my CD was scratched. What I do remember, however, is that I eventually got used to the song being played with that skip in it. I got so used to it that, even today, I can find myself rapping the chorus along with the song and reciting the lyrics as if the song should be skipping and playing out of order. That skip—that moment of discontinuity—in the song is kind of what makes it special for me and connects me back to that moment in my mother’s bedroom so many years ago. It is not an experience that is easy to describe in words, but the bottom line is that it actually felt right that the song didn’t play straight through without skipping. Something was added to the listening experience

Statistical multi-moment bifurcations in random delay coupled swarms

We study the effects of discrete, randomly distributed time delays on the dynamics of a coupled system of self-propelling particles. Bifurcation analysis on a mean field approximation of the system reveals that the system possesses patterns with certain universal characteristics that depend on distinguished moments of the time delay distribution. Specifically, we show both theoretically and numerically that although bifurcations of simple patterns, such as translations, change stability only as a function of the first moment of the time delay distribution, more complex patterns arising from Hopf bifurcations depend on all of the moments