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51	The synthesis of oligothiophene functionalized dimethyldihydropyrenes and their electrical and photochromic properties Robinson, Stephen Garfield 09 April 2008 (has links) The synthesis of benzo[e]dimethyldihydropyrene (BDHP) photoswitches with ter-27, quarter-36, and quinque-28 thiophene oligomers attached on the same side of the switch was achieved using Stille coupling reactions. BDHP photoswitches with bi-75, ter-76 and quinque-77 thiophene oligomers attached directly to the switch on one side, and via a carbonyl spacer on the opposite side of the switch were also synthesized. Dimethyldihydropyrene (DHP) photoswitches with a naphthoyl functional group in the 2 position were synthesized using a Friedel Crafts reaction, and ter-96, quinque-97 and septi-98 thiophene oligomers were attached on opposite sides of the switch using Stille coupling reactions. All compounds were characterized by NMR, IR UV-vis spectroscopy and mass spectrometry. The relative rates of the photo-opening reactions under excess light conditions and the UV closing reactions versus BDHP were measured. Improvements in the photo-opening properties of the oligothiophene functionalized switches compared to BDHP were observed. The most dramatic photo-opening improvement was found for the quinquethienyl substituted DHP switch 97 which photo-opened when irradiated with visible light over 100 times faster than BDHP. UV closing rates were virtually the same as that of BDHP. However the addition of oligothiophenes led to an increase in the thermal closing reaction rates. Compounds with the naphthoyl functional group in the 2 position of DHP were found to have dramatically increased thermal closing rates. The electrochemical properties of oligothiophene functionalized BDHP and naphthoyl functionalized DHP switches in the closed form were studied by cyclic voltammetry and spectroelectrochemistry. During the oxidation cycle, a closing reaction from the cyclophanediene (CPD) form to the DHP form of the switches occurred which prevented the study of the electrochemical properties of the switches in the open form. Conductivity testing was performed on the quinquethienyl substituted DHP switch 97 using a gold interdigitated micro electrode array. The conductivity of undoped 97 was greater in the closed DHP isomer than in the open CPD isomer. Irradiation with red or blue light allowed for repetitive switching between the more highly conducting closed form and the less conducting open form. When electrochemically doped, 97 showed improved conductivity over the undoped form but only the conductivity of the closed doped form could be measured due to electrochemically induced closing. photochromism dimethyldihydropyrene benzodimethyldihydropyrene cyclophanediene oligothiophene poly(thiophene) photochromism photochromic materials conjugation conductivity aromaticity ring current spectroelectrochemistry interdigitated micro electrode Stille coupling Weinreb amide
52	Investigations of the type ii intramolecular Diels-Alder reaction directed toward natural product synthesis Muscroft-Taylor, Andrew Clive January 2006 (has links) This thesis describes synthetic studies directed towards the total synthesis of the nakafuran and florlide marine natural products. Chapter One provides an overview of the importance of natural products to current medicinal chemistry and describes how the "supply issue" associated with these biologically derived compounds can be resolved through the process of total synthesis. Two families of marine natural products, the nakafurans and the florlides, are introduced as synthetic targets and strategies utilising a type II intramolecular Diels-Alder (IMDA) reaction to achieve their total synthesis are delineated. The efficient preparation of regio- and stereodefined vinyl coupling fragments via hydrostannylation and hydrohalogenation methodology is described in Chapter Two. The palladium-catalysed cross-coupling of these fragments, via Stille or Negishi coupling methodology, yielded dienes which were successfully advanced to IMDA triene precursors. Chapter Three describes investigation of the type II IMDA reaction to give bicyclo[4.3.1]decene carbocyclic skeletons. A facile acid-catalysed 6,7-alkene to 7,8-alkene olefinic isomerisation, via a proposed oxonium intermediate, and the inability to appropriately functionalise the desired adducts impeded progress along the synthetic route. Molecular modelling was conducted to investigate the causes of this unexpected reactivity. Investigations in Chapter Four describe the successful synthesis and cyclisation of homomethyl triene analogues prepared via application of enyne metathesis chemistry. The use of an exo-cyclopropylcarbinyl fragmentation was found to be unsuccessful as a means of installing the desired 6-methyl-bicyclo[4.3.1]decan-2-one core with a competing endo-ring expansion giving rise to a bicyclo[4.4.1]undecane ring system. Chapter 5 summarises the above results and gives a brief discussion of the future potential of this research to provide for a total synthesis of the nakafuran and florlide natural products. IMDA T2IMDA Stille Negishi Hydrostannylation Enyne metathesis Radical Fragmentation Natural product synthesis Nakafuran Xenolide Florlide Bicyclo[4.3.1]decane Bicyclo[4.3.1]decanone Bicyclo[5.3.1]undecanone
53	The Representation of Terrorism as Defective Communication in Volker Schlöndorff’s Die Stille nach dem Schuss, Gregor Schnitzler’s Was tun wenn’s brennt, Leander Scholz’s Rosenfest and Ulrike Edschmid’s Frau mit Waffe: Zwei Geschichten aus terroristischen Zeiten Dillon, Sandra I. 12 1900 (has links) ix, 213 p. / The attacks on the United States of September 11, 2001, prompted scholars in a variety of fields, such as history, philosophy and literature, to re-examine the topic of terrorism, including the emergence of terrorism in West Germany in the 1960s and 1970s. The challenges that arise when dealing with the topic of terrorism derive in part from a lack of consensus on a definition for terrorists and terrorist attacks. One element that I found in my research is that there is a connection between terrorism and communication. This dissertation examines that connection in Volker Schlöndorff's filmDie Stille nach dem Schuss Gregor Schnitzler's film Was tun wenn's brennt Leander Scholz's novel Rosenfestand Ulrike Edschmid's biographical narrativesFrau mit Waffe: Zwei Geschichten aus terroristischen Zeitenin the context of Speech Act Theory. The films and texts show how West German terrorism is represented as a form of communication, through which fictional terrorists are trying to accomplish the impossible statement "I hereby persuade you." The act of persuasion has an element of freedom, because one can either be persuaded or not. However, the terrorists represented in the works mentioned above want to eliminate the element of choice and force the interlocutor to be persuaded. In order to achieve this they introduce violence, which in turn causes them to be labeled as terrorists. The more they try to use violence to achieve their goals, the more they cement their condemnation as terrorists. This dissertation frames its investigation within ideas about performative speech acts, concepts of power, violence, identity and discussions about "terrorist" narratives in German literature and film. / Committee in charge: Susan C. Anderson， Chairperson； Alexander Mathäs， Member； Dorothee Ostmeier， Member； Bonnie Mann， Outside Member Communication German film German literature RAF Speech act theory Terrorism Communication and the arts Language, literature and linguistics Edschmid, Ulrike, 1940- Frau mit Waffe Scholz, Leander. Rosenfest Germany Film studies
54	Concise Stereoselctive Synthesis Of Aspidoalbidine Alkaloids & Spliceostatin Derivatives Josh R Born (8762934) 12 October 2021 (has links) <div>Enantioselective syntheses of hexacyclic aspidoalbidine alkaloids (+)-fendleridine and (+)-acetylaspidoalbidine are described. These syntheses feature an asymmetric decarboxylative allylation and photocyclization of a highly substituted enaminone. Also, the synthesis highlights the formation of a C19-hemiaminal ether via a reduction/condensation/intramolecular cyclization cascade with the C21-alcohol. The present synthesis provides convenient access to the aspidoalbidine hexacyclic alkaloid family in an efficient manner.</div><div>A copper-catalyzed cross-coupling is described. Use of Cu(I) salts in the presence of allyl bromides and organostannyl furans were found to undergo catalytic turnover under ambient conditions and afford the coupled products in good to great yields. Model substrate screening led to conditions used in the concise formal synthesis of FR901464 analogues. Optimization of the described coupling step led to suppression of undesired isomers and byproducts affording the desired diene coupled product in high yield, stereo-, and regioselectivity on a multigram scale. Novel protection of the resulting diene moiety as an unconventional protecting group, and a facile four-step single column chromatographic stereoselective sequence are also reported.</div> Organic Chemistry Stereochemistry Transition Metal Chemistry Natural Products Chemistry Organic Chemical Synthesis Solution Chemistry Organometallic Chemistry Natural Product Synthesis Organic Synthesis Aspidosperma Aspidoalbidine Spliceostatin FR901464 Stille Coupling Stoltz Asymmetric Allylation Alkaloids
55	(Re)casting the Self in Memory Narratives: Monika Maron’s <i>Stille Zeile sechs</i>, <i>Animal triste</i> and <i>Pawels Briefe</i> Strehlow, Kimberly Anni 27 May 2009 (has links) No description available. German literature Monika Maron <i>Stille Zeile sechs</i> <i>Pawels Briefe</i> <i>Animal triste</i> memory GDR
56	Produktion öffentlicher Räume in indischen Megastädten / Hyderabad zwischen Straßenhandel und Weltstadtanspruch / Production of Public Space in Indian Megacities / Hyderabad between Streetvending and Cosmopolitan Aspirations Grenzebach, Helene 13 December 2018 (has links) No description available. 910 550 Öffentlicher Raum Hyderabad, Indien Geographie Stadtgeographie Lefebvre, Henri Raumproduktion Globalisierung Ökonomische Liberalisierung Stadtentwicklung Stille Aneignung Politische Gesellschaft Public Space Hyderabad, India Geography Urban Geography Lefebvre, Henri Global Cities Globalization Economic Liberalization Production of Space Urban Development Silent Encroachment Political Society Geographie (PPN621264008)
57	Die vierde genre : De plaag (Van Reybrouck) as voorbeeld van literêre niefiksie Myburgh, Heilie Magdalena Magrieta 06 1900 (has links) Hierdie studie ondersoek vrae rondom die aard van literêre niefiksie - ook die vierde genre genoem. Die bestaande drieledige genreklassifikasiesisteem maak nie voldoende voorsiening vir tekste waarin die grense tussen feit en fiksie opgehef word nie. Die toename van sodanige hibriede tekste noodsaak dus ‘n uitbreiding van tradisionele genrekategorieë tot ‘n vierde, naamlik dié van literêre niefiksie. Dié ondersoek poog om vrae rondom literêre niefiksie te beantwoord met verwysing na De plaag: het stille knagen van schrijvers, termieten en Zuid-Afrika (2001) van David van Reybrouck. Dié teks dokumenteer Van Reybrouck se ondersoek na die bewering dat Maurice Maeterlinck die termietnavorsing van Eugène Marais sonder erkenning oorgeneem het. Tydens sy navorsingsreis maak Van Reybrouck kennis met die verwikkeldhede van ‘n postapartheid Suid-Afrika en verwoord sy reiservaring met behulp van metafore uit die entomologie. Die resultaat is dat De plaag ‘n hibriede karakter vertoon wat versoenbaar is met die kriteria vir literêr-niefiksionele tekste. / This study attempts to explore the nature of literary nonfiction (the fourth genre). The existing tripartite classification system does not make adequate provision for texts where the borders between nonfiction and fiction are transcended. A marked increase in such texts therefore necessitates an expansion of the traditional genre categories to accommodate a fourth, namely that of literary nonfiction. De plaag: het stille knagen van schrijvers, termieten en Zuid-Afrika (2001) by David van Reybrouck will serve as point of departure to explore the genre of literary nonfiction. The said text documents Van Reybrouck’s investigation into the alleged plagiarism by Maeterlinck of Marais’ research on termites. Van Reybrouck’s travels expose him to the complexities of a post-apartheid South Africa, which he expresses by using metaphors derived from the field of entomology. The result of this process is that De plaag displays a hybrid character which complies with the criteria for literary nonfiction. / Afrikaans and Theory of Literature / M.A. (Afrikaans) Creative nonfiction Literary nonfiction Entomology and literature Maurice Maeterlinck David van Reybrouck The fourth genre The literature of fact Hybrid genres 839.3137 Nonfiction novel Reportage literature Dutch prose literature Literary form Reybrouck, David van -- Plaag Nonfiction novel Literary form
58	Echtzeitmusik Blazanovic, Marta 03 June 2014 (has links) Die Echtzeitmusikszene ist eine zeitgenössische Musikszene, die Mitte der 1990er in Berlin entstanden ist. Seitdem entwickelte sie sich in eine umfangreiche, musikalisch vielfältige, lokale, aber auch extrem internationale Musiker-Community, mit dem Schwerpunkt auf improvisierter und experimenteller Musik. Der Begriff ‚Echtzeitmusik‘ markierte zunächst die Abgrenzung der jungen von der älteren Generation der Berliner Improvisatoren. Die jüngeren Musiker entwickelten bald eine besondere Klangästhetik sowie die Praxis des Improvisierens, was oft als ‚Berlin Reductionism‘ bezeichnet wird. Sich selbst identifizierten sie vor allem mit dem Begriff ‚Composer-Performer‘. Die musikalischen Entwicklungen in der Echtzeitmusik Szene lassen sich innerhalb der Traditionen der Freien Improvisation einerseits und der Cageschen Kompositionstheorie andererseits kontextualisieren. Ausserdem wurden die Entstehung der Szene, ihre Entwicklung und Existenz stark von den einzigartigen räumlichen, sozialen und ökonomischen Bedingungen in Berlin nach der Wende beeinflusst und bestimmt. Die Echtzeitmusik Szene ist ein Beispiel für ein hoch autonomes Feld der Kulturproduktion, in dem das sogenannte symbolische Kapital (Reputation) die wichtigste Kapitalart und ein Machtmittel darstellt. Die Verteilung des symbolischen Kapitals in der Szene manifestiert sich in einer auf den ersten Blick versteckten Hierarchie. Die Mitglieder der Szene teilen eine gemeinsame symbolische Ebene und nehmen an einem klar strukturierten und organisierten Szeneleben teil. Sowohl soziale als auch musikalische Handlungen der Szeneakteure zeigen gewisse Gemeinsamkeiten und Regularitäten, die mit Bourdieu’s Habitus-Begriff erklärt werden. Der Szenediskurs spielt eine wichtige Rolle in den Prozessen der Identifikation, Distinktion und Gemeinschaftsbildung, als auch in der Regulierung der Praxis in der Szene dadurch, dass es als ein Orientierungspunkt für die Insider, aber auch für die Aussenstehenden dient. / The Echtzeitmusik scene is a contemporary music scene that emerged in Berlin in the mid-1990s and evolved into an extensive and musically diverse local, yet extremely international community of musicians, who are involved in improvised and experimental music. The term ‘Echtzeitmusik’, literally meaning ‘real-time music’, marked the distinction between the younger and older generation of Berlin improvisers. The younger musicians had soon developed a specific sound aesthetic and approach to improvising, often labeled as ‘Berlin Reductionism’, and identified themselves as ‘composer-performers’. The musical developments in the Echtzeitmusik scene can be contextualized within the traditions of both Free Improvisation and John Cage’s compositional theory; on the other hand, the scene’s emergence, development and existence have been strongly influenced by the unique spatial, social and economic context of the post-wall Berlin from the early 1990s until today. The Echtzeitmusik scene is an example of a highly autonomous field of cultural production, in which the most important type of capital and means of “power” is the so-called symbolic capital (reputation), based on the musicians’ cultural capital (e.g. musical skill and individuality) and even more on their social capital (social relations). The distribution of symbolic capital within the scene is manifested in its, at first sight hidden, hierarchy. The members of the scene share a common symbolic level and take part in a clearly structured and organized scene-life. Both social and musical actions of the scene’s members show commonalities and regularities, which are explained by Bourdieu’s concept of habitus. The scene’s discourse plays an essential role in the processes of identification, distinction and community-making, as well as regulating the practice within the scene, by serving as a point of orientation on the inside and towards the outside. Berlin Diskurs Stille Autonomie Reduktionismus Foucault Reduktion zeitgenössische Musik Echtzeit Echtzeitmusik Szene Musikszene Improvisation experimentelle Musik Composer-Performer John Cage Geräusch Bourdieu Kapital symbolisches Kapital Habitus künstlerisches Feld Kulturproduktion Distinktion Abgrenzung Diskursfeld Interdiskursraum Berlin noise silence autonomy Reductionism discourse reduction contemporary music Echtzeit Echtzeitmusik real-time music scene improvisation experimental music composer-performer John Cage Bourdieu Foucault capital symbolic capital symbolic power habitus artistic field community of practice cultural production distinction difference discursive fields interdiscursive space 780 Musik 48 Musik CB 5100 ddc:780
59	Die vierde genre : De plaag (Van Reybrouck) as voorbeeld van literêre niefiksie Myburgh, Heilie Magdalena Magrieta 06 1900 (has links) Hierdie studie ondersoek vrae rondom die aard van literêre niefiksie - ook die vierde genre genoem. Die bestaande drieledige genreklassifikasiesisteem maak nie voldoende voorsiening vir tekste waarin die grense tussen feit en fiksie opgehef word nie. Die toename van sodanige hibriede tekste noodsaak dus ‘n uitbreiding van tradisionele genrekategorieë tot ‘n vierde, naamlik dié van literêre niefiksie. Dié ondersoek poog om vrae rondom literêre niefiksie te beantwoord met verwysing na De plaag: het stille knagen van schrijvers, termieten en Zuid-Afrika (2001) van David van Reybrouck. Dié teks dokumenteer Van Reybrouck se ondersoek na die bewering dat Maurice Maeterlinck die termietnavorsing van Eugène Marais sonder erkenning oorgeneem het. Tydens sy navorsingsreis maak Van Reybrouck kennis met die verwikkeldhede van ‘n postapartheid Suid-Afrika en verwoord sy reiservaring met behulp van metafore uit die entomologie. Die resultaat is dat De plaag ‘n hibriede karakter vertoon wat versoenbaar is met die kriteria vir literêr-niefiksionele tekste. / This study attempts to explore the nature of literary nonfiction (the fourth genre). The existing tripartite classification system does not make adequate provision for texts where the borders between nonfiction and fiction are transcended. A marked increase in such texts therefore necessitates an expansion of the traditional genre categories to accommodate a fourth, namely that of literary nonfiction. De plaag: het stille knagen van schrijvers, termieten en Zuid-Afrika (2001) by David van Reybrouck will serve as point of departure to explore the genre of literary nonfiction. The said text documents Van Reybrouck’s investigation into the alleged plagiarism by Maeterlinck of Marais’ research on termites. Van Reybrouck’s travels expose him to the complexities of a post-apartheid South Africa, which he expresses by using metaphors derived from the field of entomology. The result of this process is that De plaag displays a hybrid character which complies with the criteria for literary nonfiction. / Afrikaans and Theory of Literature / M.A. (Afrikaans) Creative nonfiction Literary nonfiction Entomology and literature Maurice Maeterlinck David van Reybrouck The fourth genre The literature of fact Hybrid genres 839.3137 Nonfiction novel Reportage literature Dutch prose literature Literary form Reybrouck, David van -- Plaag Nonfiction novel Literary form
60	Laut, Ton, Stärke Schreiner, Florian 03 May 2010 (has links) Historisch wird die Arbeit von zwei Daten her begrenzt, von den ersten hör-physiologischen Experimenten seit 1850, und von den massenwirksamen akustischen Inszenierungen der 1930er Jahre in „real auditory perspective“. Die Arbeit beginnt in Kapitel I mit dem tragischen Fall des Regisseurs und langjährigen Psychiatrie-Patienten Antonin Artaud, der die Sprache zugunsten von Lauten, Gebärden und Schreien verlässt. Seine Experimente zum Theater geben zu einer ersten Korrektur von Bildlichkeit Anlass. In Kapitel II wird der Vorrang der Bildlichkeit grundsätzlich in Frage gestellt, die Differenz von Bild und Klang wissenschaftshistorisch auseinandergesetzt, und ein „acoustic turn“ zur Welt vorbereitet. Die Untersuchungen des Physiologen und Akustikers Hermann von Helmholtz sind hier maßgeblich, denn sie beeinflussen die Technische Akustik von ihren Anfängen her. Das Kapitel III schließlich untersucht im transatlantischen Vergleich die technischen Bedingungen nach 1900. Die Beschallungsanlage hat nun die Fähigkeit, alltäglich in den Dienst genommen zu werden, und auch politischen Manipulationen diensthaft zu sein. / Historically the work is framed by two dates, by the physiological experiments of hearing and the mise en scène of a massed and sonic attack in so called „real auditory perspective“ of the 1930s. The first chapter starts with the tragedic and long living psychiatric case Antonin Artaud, who moves away from clarity of sounds to phones, gestures and crying. Such experiments give cause for a fundamental rethinking of meaning in the sense of picture, and leads to the second chapter which argues in more detail for the lap of our sonic understanding of the world. This way speeds up to an „acoutic turn“ by a retour to the biological grounds of sonic perception. The physiological and acoustic inquiries of Hermann von Helmholtz fit here to the ground for him being starting point of what will later be called „technische Akustik“. The third chapter bridges Europe´s early Telefunken-years with the United States and their chief acousticians at the legendary Bell Laboratories, and seeks finally for light in scientific amnesia against progress and control, or what the germans call „Betriebsamkeit“ and „Gestell.“ (Heidegger) Metaphysik Induktion Theater Abgrund Angst Anlage Befindlichkeit Berührung Beschallung decibel Elektroschock Futurismo Gebärde Gefühlsathletik Glockengeläut Grausamkeit Grund-Stimmung hifi-lofi Hörschwelle Innervation Intonation Klang Kultur-Betrieb Lautheit Lärmpegel Messtechnik Nachbilder Organ Phon Physiologie Präsentabilia Psychophysik Resonanzraum Schrei Sinnestäuschung Sirene Sprach-Losigkeit Sprung Schwingungsweite Stille Subjektil Tonlage Übermächtigung Wüste. sound metrology Abyss fear being touch acoustic irradiation decibel electroshock futurismo gesture athletics of feeling crualty basic tuning hifi-lofi threshold of audability inductivity innervation intonation cultural business loudness noise level metaphysics after-image organ phon physiology praesentabilia psychophysics resonance scream delusion siren loss of speech jump amplitude silence subjectil theater pitch overpowering desert 780 Musik 48 Musik EC 3520 AP 12300 ddc:780

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