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The aim of this work was the generation of carbon materials with high surface area, exhibiting a hierarchical pore system in the macro- and mesorange. Such a pore system facilitates the transport through the material and enhances the interaction with the carbon matrix (macropores are pores with diameters > 50 nm, mesopores between 2 – 50 nm). Thereto, new strategies for the synthesis of novel carbon materials with designed porosity were developed that are in particular useful for the storage of energy. Besides the porosity, it is the graphene structure itself that determines the properties of a carbon material. Non-graphitic carbon materials usually exhibit a quite large degree of disorder with many defects in the graphene structure, and thus exhibit inherent microporosity (d < 2nm). These pores are traps and oppose reversible interaction with the carbon matrix. Furthermore they reduce the stability and conductivity of the carbon material, which was undesired for the proposed applications. As one part of this work, the graphene structures of different non-graphitic carbon materials were studied in detail using a novel wide-angle x-ray scattering model that allowed precise information about the nature of the carbon building units (graphene stacks). Different carbon precursors were evaluated regarding their potential use for the synthesis shown in this work, whereas mesophase pitch proved to be advantageous when a less disordered carbon microstructure is desired. By using mesophase pitch as carbon precursor, two templating strategies were developed using the nanocasting approach. The synthesized (monolithic) materials combined for the first time the advantages of a hierarchical interconnected pore system in the macro- and mesorange with the advantages of mesophase pitch as carbon precursor. In the first case, hierarchical macro- / mesoporous carbon monoliths were synthesized by replication of hard (silica) templates. Thus, a suitable synthesis procedure was developed that allowed the infiltration of the template with the hardly soluble carbon precursor. In the second case, hierarchical macro- / mesoporous carbon materials were synthesized by a novel soft-templating technique, taking advantage of the phase separation (spinodal decomposition) between mesophase pitch and polystyrene. The synthesis also allowed the generation of monolithic samples and incorporation of functional nanoparticles into the material. The synthesized materials showed excellent properties as an anode material in lithium batteries and support material for supercapacitors.
This book endeavours to understand the seemingly direct link between utopianism and the USA, discussing novels that have never been brought together in this combination before, even though they all revolve around intentional communities: Imlay’s The Emigrants (1793), Hawthorne’s The Blithedale Romance (1852), Howland’s Papas Own Girl (1874), Griggs’s Imperium in Imperio (1899), and Du Bois’s The Quest of the Silver Fleece (1911). They relate nation and utopia not by describing perfect societies, but by writing about attempts to immediately live radically different lives. Signposting the respective communal history, the readings provide a literary perspective to communal studies, and add to a deeply necessary historicization for strictly literary approaches to US utopianism, and for studies that focus on Pilgrims/Puritans/Founding Fathers as utopian practitioners. This book therefore highlights how the authors evaluated the USA’s utopian potential and traces the nineteenth-century development of the utopian imagination from various perspectives.
Digital inclusion
(2021)
In this thesis, we tackle two social disruptions: recent refugee waves in Germany and the COVID-19 pandemic. We focus on the use of information and communication technology (ICT) as a key means of alleviating these disruptions and promoting social inclusion. As social disruptions typically lead to frustration and fragmentation, it is essential to ensure the social inclusion of individuals and societies during such times.
In the context of the social inclusion of refugees, we focus on the Syrian refugees who arrived in Germany as of 2015, as they form a large and coherent refugee community. In particular, we address the role of ICTs in refugees’ social inclusion and investigate how different ICTs (especially smartphones and social networks) can foster refugees’ integration and social inclusion. In the context of the COVID-19 pandemic, we focus on the widespread unconventional working model of work from home (WFH). Our research here centers on the main constructs of WFH and the key differences in WFH experiences based on personal characteristics such as gender and parental status.
We reveal novel insights through four well-established research methods: literature review, mixed methods, qualitative method, and quantitative method. The results of our research have been published in the form of eight articles in major information systems venues and journals. Key results from the refugee research stream include the following: Smartphones represent a central component of refugee ICT use; refugees view ICT as a source of information and power; the social connectedness of refugees is strongly correlated with their Internet use; refugees are not relying solely on traditional methods to learn the German language or pursue further education; the ability to use smartphones anytime and anywhere gives refugees an empowering feeling of global connectedness; and ICTs empower refugees on three levels (community participation, sense of control, and self-efficacy).
Key insights from the COVID-19 WFH stream include: Gender and the presence of children under the age of 18 affect workers’ control over their time, technology usefulness, and WFH conflicts, while not affecting their WFH attitudes; and both personal and technology-related factors affect an individual’s attitude toward WFH and their productivity. Further insights are being gathered at the time of submitting this thesis.
This thesis contributes to the discussion within the information systems community regarding how to use different ICT solutions to promote the social inclusion of refugees in their new communities and foster an inclusive society. It also adds to the growing body of research on COVID-19, in particular on the sudden workplace transformation to WFH. The insights gathered in this thesis reveal theoretical implications and future opportunities for research in the field of information systems, practical implications for relevant stakeholders, and social implications related to the refugee crisis and the COVID-19 pandemic that must be addressed.
Vertragsgestaltung ist ein praktisch sehr relevantes Thema, das wegen der Justizorientierung in der Wissenschaft noch weitgehend stiefmütterlich behandelt wird. In dieser Untersuchung wird, zumindest für die besonders delikate Konstellation bei komplexen Kooperationen des Staats mit Privaten (ÖPP/PPP), Abhilfe geschaffen. Dabei gründet die Analyse auf einer fundierten Typisierung und Charakterisierung der Probleme solcher Projekte. Den theoretischen Rahmen liefert eine effizienzorientierte Studie institutionenökonomischer Ansätze, namentlich der Transaktionskostentheorie und der Prinzipal-Agenten-Theorie, rückversichert über die praxisorientierten Grundregeln der vertraglichen Risikoverteilung. So gelingt es praktische Formulierungsvorschläge für Standardprobleme der Vertragsgestaltung, wie Leistungsbestimmungen, Anpassungsmechanismen, Konfliktbeilegungsregeln, Informationsmechanismen und Kündigungsregeln zu finden. Diese werden auch aus den Erfolgsbedingungen erläutert.
Health effects, attributed to the environmental pollution resulted from using solvents such as benzene, are relatively unexplored among petroleum workers, personal use, and laboratory researchers. Solvents can cause various health problems, such as neurotoxicity, immunotoxicity, and carcinogenicity. As such it can be absorbed via epidermal or respiratory into the human body resulting in interacting with molecules that are responsible for biochemical and physiological processes of the brain.
Owing to the ever-growing demand for finding a solution, an Ionic liquid can use as an alternative solvent. Ionic liquids are salts in a liquid state at low temperature (below 100 C), or even at room temperature. Ionic liquids impart a unique architectural platform, which has been interesting because of their unusual properties that can be tuned by simple ways such as mixing two ionic liquids.
Ionic liquids not only used as reaction solvents but they became a key developing for novel applications based on their thermal stability, electric conductivity with very low vapor pressure in contrast to the conventional solvents.
In this study, ionic liquids were used as a solvent and reactant at the same time for the novel nanomaterials synthesis for different applications including solar cells, gas sensors, and water splitting.
The field of ionic liquids continues to grow, and become one of the most important branches of science. It appears to be at a point where research and industry can work together in a new way of thinking for green chemistry and sustainable production.
Die vorliegende Arbeit trägt den Titel: Intellektuellen-Rolle in Günter Grass Werken : „Die Plebejer proben den Aufstand“(1966), „Örtlich betäubt“(1969), „Aus dem Tagebuch einer Schnecke“(1972), und „Ein weites Feld“(1995).
Das erste Kapitel befasst sich insgesamt mit drei Haupttiteln
II. Der Intellektuelle
II.1 Das allgemeine Umfeld
In diesem Teil der Dissertation sollen Aussagen getroffen werden, die auf folgende und weitere Fragen eine Antwort geben: Was ist ein Intellektueller? Wie kam der Begriff zustande? Gibt es Unterschiede zwischen den Intellektuellen und wie werden sie eingeteilt?
II.2 Das deutsche Umfeld
Die Behandlung des Nazisystems und dessen historische Hintergründe vermittelt bedeutsame Lehren. Aber wozu braucht man diese Lehren? Gibt es Spuren von Nationalsozialismus heutzutage? Wo waren die Intellektuellen bei der Bildung des Nationalsozialismus? Ist der Nationalsozialismus erst mit Hitler aufgetaucht? Wenn zuvor, in welcher Phase hat er sich im Bewusstsein der Deutschen verankert? Ob theoretische bzw. geistige Tendenzen dazu beigetragen haben?
II.3 Das Bild von Grass als Intellektueller
II.3.1 Positionierung
Eine Hauptthese für Grass intellektuelle Positionierung wird durch die Verbindung zwischen Grass’ Grundkonzeption der gesellschaftspolitischen Intellektualität und der Gruppe 47 ermittelt. Dann bezweckt die Behandlung von Grass Bild nach Erscheinen seines autobiographischen Werks: „Beim Häuten der Zwiebel“ (2006), dass seine Intellektualität nicht nur aus dem positiven, sondern auch aus dem negativen Profil beleuchtet wird.
Aus der Darstellung zahlreicher Ansichten von Günter Grass werden fünf thematische Kernpunkte als Konzepte behandelt. Unter jedem Konzept sollen spezifische Vorschläge zur gesellschaftlichen Positionierung aufgezeigt werden.
II.3.2 Grass’ politische Merkmale
Es handelt sich hier um die intellektuellen Charaktereigenschaften. Dadurch kommen manche Fragen zu Wort: Hat Günter Grass gesellschaftliche Aktivitäten? Hat er die Voraussetzungen dafür? Wie ist der Umfang seiner Aktivitäten? Hat die Gruppe 47 Einfluss auf Grass intellektuelle Merkmale? Steht bei Grass eine Methode der gesellschaftspolitischen Arbeit zur Verfügung?
Dann wird die politische Sprache von Günter Grass und ihre Wirkung auf den Rezipienten untersucht. Danach wird nach Grass’ Auffassung von der Revision gefragt und ob sie mit seiner Auffassung der Aufklärung zusammenpasst. Darauf wird die Funktion der Revision in seinem literarischen Werk und in seiner gesellschaftspolitischen Aktivität gezeigt.
Abschließend werden die Argumente seiner Intellektualität untersucht:
Wie hat Grass’ gesellschaftspolitische Aktivität den konkreten politischen Rahmen berücksichtigt? Um diese Frage zu beantworten, muss der Zusammenhang zwischen Politik und Moral verdeutlicht werden.
III. Historischer Kontext und Inhalt der Werke
Unter diesem Titel wird erstens der historische Zusammenhang der untersuchten Werke skizziert. Dann werden meistens durch Argumente aus jedem Werk selbst nicht nur der Kern des Werkes und sein Handlungsverlauf, sondern auch die dafür angewandte Methode dargestellt.
IV. Bezug der untersuchten Werke zu konkreten gesellschaftspolitischen Fragen
IV.1 Interaktionswege des Intellektuellen mit der Gesellschaft, vor allem beim Wandel gesellschaftspolitischer Prozesse
Zentralkonzepte des ersten Werkes sind: Vermittlung, Engagement, Solidarität und die Aktualität als Maßstab. Diese werden durch zwei Konzepte des zweiten Werkes: Appell an Generationen beim Wechsel und Zusammenhaltsprinzip an Revision gebunden, sowie durch die Behandlung vom Prozess der Meinungsbildung im vierten Werk ausgearbeitet.
IV.2 Thematische Aspekte zur Vermeidung eines Naziregimes
Aus den thematischen Perspektiven der drei letzten Werke geht eine bunte Sammlung intellektueller Konzepte aus, die zur Bekämpfung von Nazivorsprünge verwendet werden können.
V. Pädagogische Strategien der untersuchten Werke
Die pädagogischen Aspekte der untersuchten Werke sollen intellektuelle Werte vermitteln, die einen bedeutenden Beitrag zur Lösung gesellschaftspolitischer Probleme und Konflikte leisten.
VI. Entwicklung der literarischen und gesellschaftspolitischen Vision
Hier wird die Entwicklungslinie der gesellschaftspolitischen Vision in den untersuchten Werken verfolgt.
VII. Zur Rezeption der vier Werke
Durch die Auseinandersetzung mit der negativen Kritik wird angestrebt, ihre Subjektivität darzulegen, damit der gesellschaftspolitische Wert der vier Werke enthüllt wird.
Parameterisierung atmosphärischer Grenzschichtprozesse in einem regionalen Klimamodell der Arktis
(1998)
Linked Open Data (LOD) comprises very many and often large public data sets and knowledge bases. Those datasets are mostly presented in the RDF triple structure of subject, predicate, and object, where each triple represents a statement or fact. Unfortunately, the heterogeneity of available open data requires significant integration steps before it can be used in applications. Meta information, such as ontological definitions and exact range definitions of predicates, are desirable and ideally provided by an ontology. However in the context of LOD, ontologies are often incomplete or simply not available. Thus, it is useful to automatically generate meta information, such as ontological dependencies, range definitions, and topical classifications. Association rule mining, which was originally applied for sales analysis on transactional databases, is a promising and novel technique to explore such data. We designed an adaptation of this technique for min-ing Rdf data and introduce the concept of “mining configurations”, which allows us to mine RDF data sets in various ways. Different configurations enable us to identify schema and value dependencies that in combination result in interesting use cases. To this end, we present rule-based approaches for auto-completion, data enrichment, ontology improvement, and query relaxation. Auto-completion remedies the problem of inconsistent ontology usage, providing an editing user with a sorted list of commonly used predicates. A combination of different configurations step extends this approach to create completely new facts for a knowledge base. We present two approaches for fact generation, a user-based approach where a user selects the entity to be amended with new facts and a data-driven approach where an algorithm discovers entities that have to be amended with missing facts. As knowledge bases constantly grow and evolve, another approach to improve the usage of RDF data is to improve existing ontologies. Here, we present an association rule based approach to reconcile ontology and data. Interlacing different mining configurations, we infer an algorithm to discover synonymously used predicates. Those predicates can be used to expand query results and to support users during query formulation. We provide a wide range of experiments on real world datasets for each use case. The experiments and evaluations show the added value of association rule mining for the integration and usability of RDF data and confirm the appropriateness of our mining configuration methodology.
We establish elements of a new approach to ellipticity and parametrices within operator algebras on manifolds with higher singularities, only based on some general axiomatic requirements on parameter-dependent operators in suitable scales of spaes. The idea is to model an iterative process with new generations of parameter-dependent operator theories, together with new scales of spaces that satisfy analogous requirements as the original ones, now on a corresponding higher level. The "full" calculus involves two separate theories, one near the tip of the corner and another one at the conical exit to infinity. However, concerning the conical exit to infinity, we establish here a new concrete calculus of edge-degenerate operators which can be iterated to higher singularities.