Proton Diffusion Mechanism in Hydrated Barium Indate Oxides

We report on quasielastic neutron scattering (QENS) andab initiomolecular dynamics (AIMD) simulations of the mechanism of proton diffusionin the partially and fully hydrated barium indate oxide proton conductorsBa(2)In(2)O(5)(H2O)( x ) (x = 0.30 and 0.92). Structurally,these materials are featured by an intergrowth of cubic and "pseudo-cubic"layers of InO6 octahedra, wherein two distinct proton sites,H(1) and H(2), are present. We show that the main localized dynamicsof these protons can be described as rotational diffusion of O-H(1)species and H(2) proton transfers between neighboring oxygen atoms.The mean residence times of both processes are in the order of picosecondsin the two studied materials. For the fully hydrated material, Ba2In2O5(H2O)(0.92), we also reveal the presence of a third proton site, H(3), whichbecomes occupied upon increasing the temperature and serves as a saddlestate for the interexchange between H(1) and H(2) protons. Crucially,the occupation of the H(3) site enables long-range diffusion of protons,which is highly anisotropic in nature and occurs through a two-dimensionalpathway. For the partially hydrated material, Ba2In2O5(H2O)(0.30), the occupationof the H(3) site and subsequent long-range diffusion are not observed,which is rationalized by hindered dynamics of H(2) protons in thevicinity of oxygen vacancies. A comparison to state-of-the-art proton-conductingoxides, such as barium zirconate-based materials, suggests that thegenerally lower proton conductivity in Ba2In2O5(H2O)( x ) is dueto a large occupation of the H(1) and H(2) sites, which, in turn,means that there are few sites available for proton diffusion. Thisinsight suggests that the chemical substitution of indium by cationswith higher oxidation states offers a novel route toward higher protonconductivity because it reduces the proton site occupancy while preservingan oxygen-vacancy-free structure

A Novel Multicell DC-AC Converter for Applications in Renewable Energy Systems

Abstract-This paper presents a novel dc-ac converter for applications in the area of distributed energy generation systems, e.g., solar power systems, fuel-cell power systems in combination with supercapacitor or battery energy storage. The proposed converter is realized using an isolated multicell topology where the total ac output of the system is formed by series connection of several full-bridge converter stages. The dc links of the full bridges are supplied by individual dc-dc isolation stages which are arranged in parallel concerning the dc input of the total system. Therefore, all switching cells of the proposed converter can be equipped with modern low-voltage high-current power MOSFETs, which results in an improved efficiency as compared to conventional isolated dc-ac converters. Furthermore, the cells are operated in an interleaved pulsewidth-modulation mode which, in connection with the low voltage level of each cell, significantly reduces the filtering effort on the ac output of the overall system. The paper describes the operating principle, analyzes the fundamental relationships which are relevant for component selection, and presents a specific circuit design. Finally, measurements taken from a 2-kW laboratory model are presented

Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

Analyse der Emissionsminderungspotentiale von Heizsystemen im österreichischen Gebäudebestand

Die Diplomarbeit beschäftigt sich hauptsächlich mit ökologischen Aspekten von Heizungssystemen mit Bezug zum österreichischen Gebäudebestand.Zentrale Fragestellungen:1.) Wie hoch sind Schadstoff- und Treibhausgasemissionen der vorherrschenden Heizungssysteme? 2.) Wie verändert sich die Emissionssituation, wenn innovative Heizungssysteme implementiert werden? 3.) Wie hoch sind die österreichischen Emissionen aus Raumwärme und Warmwassererzeugung? 4.) Was würde sich unter Zugrundelegung anderer (erstrebenswerter) Verteilungen der Heizungssysteme verändern? CO2-Äquivalente (Treibhausgase), SO2-Äquivalente (Versauerung), TOPP-Äquivalente (Ozonbildung), Staub und kumulierter Energieaufwand werden berechnet.Zwischen vier Gebäudegrößen und sieben Bauperioden wird unterschieden.Für jede der 28 Gebäudegruppen wird die momentane Heizungsstruktur dargestellt.Durch Untersuchung von Gebäudedaten, Heizungsanlagen sowie Benutzerverhalten wird der jährliche Endenergiebedarf errechnet.Die Emissionen werden mit dem Computerprogramm GEMIS berechnet.Wesentliche Ergebnisse:1.) Kohleheizungen haben hohe Emissionen.2.) Gas ist umweltfreundlicher als Öl.3.) Holzheizungen haben niedrige Treibhausgas-, aber hohe Staubemissionen.4.) Fernwärme ist relativ umweltfreundlich, allerdings ist unklar, welche Emissionen eingerechnet werden müssen.5.) Wärmepumpen liegen relativ gut. Die Gebäudedämmung und der Strommix beeinflussen die Ergebnisse stark.6.) Solaranlagen sind umweltfreundlich, ihr Deckungsgrad ist niedrig.Weiters werden gesamtösterreichische Emissionen berechnet. Durch Szenarienbildung zur Heizungserneuerung und Gebäudesanierung werden beachtliche Einsparpotentiale aufgezeigt.Anschließend folgt ein wirtschaftlicher Vergleich. Unsichere Parameter (Abschreibungsdauer, Energiepreisentwicklung, Zinssatz, Kosten wie Anschlussgebühr) machen Aussagen schwierig. Holzheizungen und Wärmepumpen benötigen höhere Investitionskosten, sind dafür im Betrieb günstiger als Öl und Gas. Öl ist teurer als Gas. Fernwärme ist relativ günstig.Hindernisse bei der Implementierung moderner Heizungssysteme (Biomasse, Wärmepumpen, Solaranlagen) und Fehler bei der Verwendung von Heizungen werden aufgezeigt.Weiters werden Gesetze zur Inverkehrbringung und Überprüfung von Heizungsanlagen zusammengefasst.This diploma thesis deals with ecological aspects of heating systems, related to Austrian buildings. CO2-equivalent-emissions, SO2-equivalent-emissions, TOPP-equivalent-emissions, smoke and total energy demand are calculated.Main questions:1.) How high are the emissions of greenhouse gases and air pollutants? 2.) How does the situation change if modern heating systems are installed? 3.) How high are the emissions in Austria caused by heating? 4.) How would that change if newer heating systems are installed? 7 building periods and 4 building-sizes are distinguished.By evaluation of data of Austrian buildings, heating systems and the behaviour of people the site energy demand is calculated.Emissions are calculated by "GEMIS".Main results:1.) Coal heatings show high emissions.2.) Gas is better than oil.3.) Wood emits much smoke but low greenhouse gases.4.) District heat is difficult to calculate, because it is not clear which emissions have to be included.5.) Heat pumps show quite low emissions, but results depend on electricity mix and thermal quality of the builiding.6.) Solar systems are good for environment, but their potential is low.Total Austrian emissions are calculated and high potentials for reducing emissions by replacing heating systems are shown.Many variables (development of energy prices, lifetime of heating systems, interest...) make an economical analysis difficult. Wood heatings and heat pumps need higher capital costs but lower current costs than gas and oil. Furthermore restrictions for the implementation of modern technologies and mistakes regarding the usage of heating systems are discussed.19