855 resultados para Competitive Exclusion Principle


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THE TITLE OF MY THESIS IS THE ROLE OF THE IDEAS AND THEIR CHANGE IN HIGHER EDUCATION POLICY-MAKING PROCESSES FROM THE EIGHTIES TO PRESENT-DAY: THE CASES OF ENGLAND AND NEW ZEALAND IN COMPARATIVE PERSPECTIVE UNDER A THEORETICAL POINT OF VIEW, THE AIM OF MY WORK IS TO CARRY OUT A RESEARCH MODELLED ON THE CONSTRUCTIVIST THEORY. IT FOCUSES ON THE ANALYSIS OF THE IMPACT OF IDEAS ON THE PROCESSES OF POLICY MAKING BY MEANS OF EPISTEMIC COMMUNITIES, THINK TANKS AND VARIOUS SOCIOECONOMIC CONTEXTS THAT MAY HAVE PLAYED A KEY ROLE IN THE CONSTRUCTION OF THE DIFFERENT PATHS. FROM MY POINT OF VIEW IDEAS CONSTITUTE A PRIORITY RESEARCH FIELD WHICH IS WORTH ANALYSING SINCE THEIR ROLE IN POLICY MAKING PROCESSES HAS BEEN TRADITIONALLY RATHER UNEXPLORED. IN THIS CONTEXT AND WITH THE AIM OF DEVELOPING A RESEARCH STRAND BASED ON THE ROLE OF IDEAS, I INTEND TO CARRY ON MY STUDY UNDER THE PERSPECTIVE OF CHANGE. DEPENDING ON THE DATA AND INFORMATION THAT I COLLECTED I EVALUATED THE WEIGHT OF EACH OF THESE VARIABLES AND MAYBE OTHERS SUCH AS THE INSTITUTIONS AND THE INDIVIDUAL INTERESTS, WHICH MAY HAVE INFLUENCED THE FORMATION OF THE POLICY MAKING PROCESSES. UNDER THIS LIGHT, I PLANNED TO ADOPT THE QUALITATIVE METHODOLOGY OF RESEARCH WHICH I BELIEVE TO BE VERY EFFECTIVE AGAINST THE MORE DIFFICULT AND POSSIBLY REDUCTIVE APPLICATION OF QUANTITIVE DATA SETS. I RECKON THEREFORE THAT THE MOST APPROPRIATE TOOLS FOR INFORMATION PROCESSING INCLUDE CONTENT ANALYSIS, AND IN-DEPTH INTERVIEWS TO PERSONALITIES OF THE POLITICAL PANORAMA (ÉLITE OR NOT) WHO HAVE PARTICIPATED IN THE PROCESS OF HIGHER EDUCATION REFORM FROM THE EIGHTIES TO PRESENT-DAY. THE TWO CASES TAKEN INTO CONSIDERATION SURELY SET AN EXAMPLE OF RADICAL REFORM PROCESSES WHICH HAVE OCCURRED IN QUITE DIFFERENT CONTEXTS DETERMINED BY THE SOCIOECONOMIC CHARACTERISTICS AND THE TRAITS OF THE ÉLITE. IN NEW ZEALAND THE DESCRIBED PROCESS HAS TAKEN PLACE WITH A STEADY PACE AND A GOOD GRADE OF CONSEQUANTIALITY, IN LINE WTH THE REFORMS IN OTHER STATE DIVISIONS DRIVEN BY THE IDEAS OF THE NEW PUBLIC MANAGEMENT. CONTRARILY IN ENGLAND THE REFORMATIVE ACTION OF MARGARET THATCHER HAS ACQUIRED A VERY RADICAL CONNOTATION AS IT HAS BROUGHT INTO THE AMBIT OF HIGHER EDUCATION POLICY CONCEPTS LIKE EFFICIENCY, EXCELLENCE, RATIONALIZATION THAT WOULD CONTRAST WITH THE GENERALISTIC AND MASS-ORIENTED IDEAS THAT WERE FASHIONABLE DURING THE SEVENTIES. THE MISSION I INTEND TO ACCOMPLISH THORUGHOUT MY RESEARCH IS TO INVESTIGATE AND ANALYSE INTO MORE DEPTH THE DIFFERENCES THAT SEEM TO EMERGE FROM TWO CONTEXTS WHICH MOST OF THE LITERATURE REGARDS AS A SINGLE MODEL: THE ANGLO-SAXON MODEL. UNDER THIS LIGHT, THE DENSE ANALYSIS OF POLICY PROCESSES ALLOWED TO BRING OUT BOTH THE CONTROVERSIAL AND CONTRASTING ASPECTS OF THE TWO REALITIES COMPARED, AND THE ROLE AND WEIGHT OF VARIABLES SUCH AS IDEAS (MAIN VARIABLE), INSTITUTIONAL SETTINGS AND INDIVIDUAL INTERESTS ACTING IN EACH CONTEXT. THE CASES I MEAN TO ATTEND PRESENT PECULIAR ASPECTS WORTH DEVELOPING AN IN-DEPTH ANALYSIS, AN OUTLINE OF WHICH WILL BE PROVIDED IN THIS ABSTRACT. ENGLAND THE CONSERVATIVE GOVERNMENT, SINCE 1981, INTRODUCED RADICAL CHANGES IN THE SECTOR OF HIGHER EDUCATION: FIRST CUTTING DOWN ON STATE FUNDINGS AND THEN WITH THE CREATION OF AN INSTITUTION FOR THE PLANNING AND LEADERSHIP OF THE POLYTECHNICS (NON-UNIVERSITY SECTOR). AFTERWARDS THE SCHOOL REFORM BY MARGARET THATCHER IN 1988 RAISED TO A GREAT STIR ALL OVER EUROPE DUE TO BOTH ITS CONSIDERABLE INNOVATIVE IMPRINT AND THE STRONG ATTACK AGAINST THE PEDAGOGY OF THE ‘ACTIVE’ SCHOOLING AND PROGRESSIVE EDUCATION, UNTIL THEN RECOGNIZED AS A MERIT OF THE BRITISH PUBLIC SCHOOL. IN THE AMBIT OF UNIVERSITY EDUCATION THIS REFORM, TOGETHER WITH SIMILAR MEASURES BROUGHT IN DURING 1992, PUT INTO PRACTICE THE CONSERVATIVE PRINCIPLES THROUGH A SERIES OF ACTIONS THAT INCLUDED: THE SUPPRESSION OF THE IRREMOVABILITY PRINCIPLE FOR UNIVERSITY TEACHERS; THE INTRODUCTION OF STUDENT LOANS FOR LOW-INCOME STUDENTS AND THE CANCELLATION OF THE CLEAR DISTINCTION BETWEEN UNIVERSITIES AND POLYTECHNICS. THE POLICIES OF THE LABOUR MAJORITY OF MR BLAIR DID NOT QUITE DIVERGE FROM THE CONSERVATIVES’ POSITION. IN 2003 BLAIR’S CABINET RISKED TO BECOME A MINORITY RIGHT ON THE OCCASION OF AN IMPORTANT UNIVERSITY REFORM PROPOSAL. THIS PROPOSAL WOULD FORESEE THE AUTONOMY FOR THE UNIVERSITIES TO RAISE UP TO 3.000 POUNDS THE ENROLMENT FEES FOR STUDENTS (WHILE FORMERLY THE CEILING WAS 1.125 POUNDS). BLAIR HAD TO FACE INTERNAL OPPOSITION WITHIN HIS OWN PARTY IN RELATION TO A MEASURE THAT, ACCORDING TO THE 150 MPS PROMOTERS OF AN ADVERSE MOTION, HAD NOT BEEN INCLUDED IN THE ELECTORAL PROGRAMME AND WOULD RISK CREATING INCOME-BASED DISCRIMINATION AMONG STUDENTS. AS A MATTER OF FACT THE BILL FOCUSED ON THE INTRODUCTION OF VERY LOW-INTEREST STUDENT LOANS TO BE SETTLED ONLY WHEN THE STUDENT WOULD HAVE FOUND A REMUNERATED OCCUPATION (A SYSTEM ALREADY PROVIDED FOR BY THE AUSTRALIAN LEGISLATION). NEW ZEALAND CONTRARILY TO MANY OTHER COUNTRIES, NEW ZEALAND HAS ADOPTED A VERY WIDE VISION OF THE TERTIARY EDUCATION. IT INCLUDES IN FACT THE FULL EDUCATIONAL PROGRAMME THAT IS INTERNATIONALLY RECOGNIZED AS THE POST-SECONDARY EDUCATION. SHOULD WE SPOTLIGHT A PECULIARITY OF THE NEW ZEALAND TERTIARY EDUCATION POLICY THEN IT WOULD BE ‘CHANGE’. LOOKING AT THE REFORM HISTORY RELATED TO THE TERTIARY EDUCATION SYSTEM, WE CAN CLEARLY IDENTIFY FOUR ‘SUB-PERIODS’ FROM THE EIGHTIES TO PRESENT-DAY: 1. BEFORE THE 80S’: AN ELITARIAN SYSTEM CHARACTERIZED BY LOW PARTICIPATION RATES. 2. BETWEEN MID AND LATE 80S’: A TREND TOWARDS THE ENLARGEMENT OF PARTICIPATION ASSOCIATED TO A GREATER COMPETITION. 3. 1990-1999: A FUTHER STEP TOWARDS A COMPETITIVE MODEL BASED ON THE MARKET-ORIENTED SYSTEM. 4. FROM 2000 TO TODAY: A CONTINUOUS EVOLUTION TOWARDS A MORE COMPETITIVE MODEL BASED ON THE MARKET-ORIENTED SYSTEM TOGETHER WITH A GROWING ATTENTION TO STATE CONTROL FOR SOCIAL AND ECONOMIC DEVELOPMENT OF THE NATION. AT PRESENT THE GOVERNMENT OF NEW ZEALAND OPERATES TO STRENGHTHEN THIS PROCESS, PRIMARILY IN RELATION TO THE ROLE OF TERTIARY EDUCATION AS A STEADY FACTOR OF NATIONAL WALFARE, WHERE PROFESSIONAL DEVELOPMENT CONTRIBUTES ACTIVELY TO THE GROWTH OF THE NATIONAL ECONOMIC SYSTEM5. THE CASES OF ENGLAND AND NEW ZEALAND ARE THE FOCUS OF AN IN-DEPTH INVESTIGATION THAT STARTS FROM AN ANALYSIS OF THE POLICIES OF EACH NATION AND DEVELOP INTO A COMPARATIVE STUDY. AT THIS POINT I ATTEMPT TO DRAW SOME PRELIMINARY IMPRESSIONS ON THE FACTS ESSENTIALLY DECRIBED ABOVE. THE UNIVERSITY POLICIES IN ENGLAND AND NEW ZEALAND HAVE BOTH UNDERGONE A SIGNIFICANT REFORMATORY PROCESS SINCE THE EARLY EIGHTIES; IN BOTH CONTEXTS THE IMPORTANCE OF IDEAS THAT CONSTITUTED THE BASE OF POLITICS UNTIL 1980 WAS QUITE RELEVANT. GENERALLY SPEAKING, IN BOTH CASES THE PRE-REFORM POLICIES WERE INSPIRED BY EGALITARIANISM AND EXPANSION OF THE STUDENT POPULATION WHILE THOSE BROUGHT IN BY THE REFORM WOULD PURSUE EFFICIENCY, QUALITY AND COMPETITIVENESS. UNDOUBTEDLY, IN LINE WITH THIS GENERAL TENDENCY THAT REFLECTS THE HYPOTHESIS PROPOSED, THE TWO UNIVERSITY SYSTEMS PRESENT SEVERAL DIFFERENCES. THE UNIVERSITY SYSTEM IN NEW ZEALAND PROCEEDED STEADILY TOWARDS THE IMPLEMENTATION OF A MANAGERIAL CONCEPTION OF TERTIARY EDUCATION, ESPECIALLY FROM 1996 ONWARDS, IN ACCORDANCE WITH THE REFORMATORY PROCESS OF THE WHOLE PUBLIC SECTOR. IN THE UNITED KINGDOM, AS IN THE REST OF EUROPE, THE NEW APPROACH TO UNIVERSITY POLICY-MAKING HAD TO CONFRONT A DEEP-ROOTED TRADITION OF PROGRESSIVE EDUCATION AND THE IDEA OF EDUCATION EXPANSION THAT IN FACT DOMINATED UNTIL THE EIGHTIES. FROM THIS VIEW POINT THE GOVERNING ACTION OF MARGARET THATCHER GAVE RISE TO A RADICAL CHANGE THAT REVOLUTIONIZED THE OBJECTIVES AND KEY VALUES OF THE WHOLE EDUCATIONAL SYSTEM, IN PARTICULAR IN THE HIGHER EDUCATION SECTOR. IDEAS AS EFFICIENCY, EXCELLENCE AND CONTROL OF THE PERFORMANCE BECAME DECISIVE. THE LABOUR CABINETS OF BLAIR DEVELOPED IN THE WAKE OF CONSERVATIVE REFORMS. THIS APPEARS TO BE A FOCAL POINT OF THIS STUDY THAT OBSERVES HOW ALSO IN NEW ZEALAND THE REFORMING PROCESS OCCURRED TRANSVERSELY DURING PROGRESSIVE AND CONSERVATIVE ADMINISTRATIONS. THE PRELIMINARY IMPRESSION IS THEREFORE THAT IDEAS DEEPLY MARK THE REFORMATIVE PROCESSES: THE AIM OF MY RESEARCH IS TO VERIFY TO WHICH EXTENT THIS STATEMENT IS TRUE. IN ORDER TO BUILD A COMPREHENSIVE ANALYLIS, FURTHER SIGNIFICANT FACTORS WILL HAVE TO BE INVESTIGATED: THE WAY IDEAS ARE PERCEIVED AND IMPLEMENTED BY THE DIFFERENT POLITICAL ELITES; HOW THE VARIOUS SOCIOECONOMIC CONTEXTS INFLUENCE THE REFORMATIVE PROCESS; HOW THE INSTITUTIONAL STRUCTURES CONDITION THE POLICY-MAKING PROCESSES; WHETHER INDIVIDUAL INTERESTS PLAY A ROLE AND, IF YES, TO WHICH EXTENT.

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In order to eliminate the de Gennes packing problem, which usually limits the attainable size of dendrimers, a new branching unit containing para-tetraphenylene ethynyl arms has been synthesized and utilized in the preparation of dendrimers of the Müllen type. The divergent principle of synthesis, based on the Dilthey reaction, could be carried up to sixth generation which contains 2776 benzene rings and possesses a diameter in the 27 nm range ("exploded dendrimer"). Monodispersity and dimensions of this and the lower generation species have been studied by MALDI-TOF MS (including the very recent superconducting tunnel junction detector), by size-exclusion chromatography, dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Interesting features, apart from the huge dimension, are the low density and high porosity of these giant molecules which cause extensive aggregation in the gas phase, flattening on solid support (AFM) and the ready incorporation of guest molecules in the condensed phase. Since the synthesis of the para-tetraphenylene arms is quite elaborate, similar dendrimers containing para-terphenylene arms have been prepared; they are accessible more economically ("semi-exploded dendrimers"). It has been shown that they in several aspects mimic the features of the "exploded dendrimers". In order to take advantage of the presence of large internal cavities in this dendrimer type, dendrons containing -C≡C- triple bonds have also been incorporated. Surprisingly, they are readily hydrogenated under the condition of heterogeneous catalysis (Pd/C) which demonstrates the large size of the cavities. As revealed by a quartz microbalance study the post-hydrogenation dendrimers are less prone to incorporate guest molecules than before hydrogenation. Obviously, the more flexible nature of the former reduces porosity, it also leads to significant shrinkage. An interesting perspective is the use of homogeneous hydrogenation catalysts of variable size with the aim of determining the dimension of internal free space.

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In this work, an improved protocol for inverse size-exclusion chromatography (ISEC) was established to assess important pore structural data of porous silicas as stationary phases in packed chromatographic columns. After the validity of the values generated by ISEC was checked by comparison with data obtained from traditional methods like nitrogen sorption at 77 K (Study A), the method could be successfully employed as valuable tool at the development of bonded poly(methacrylate)-coated silicas, while traditional methods generate partially incorrect pore structural information (Study B). Study A: Different mesoporous silicas were converted by a pseudomorphical transition into ordered MCM-41-type silica while maintaining the particle-size and -shape. The essential parameters like specific surface area, average pore diameter and specific pore volume, the pore connectivity from ISEC remained nearly the same which was reflected by the same course of the theoretical plate height vs. linear velocity curves. Study B: In the development of bonded poly(methacrylate)-coated silicas for the reversed phase separation of biopolymers, ISEC was the only method to generate valid pore structural information of the polymer-coated materials. Synthesis procedures were developed to obtain reproducibly covalently bonded poly(methacrylate) coatings with good thermal stability on different base materials, employing as well particulate and monolithic materials.

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Microcredit has been a tool to alleviate poverty since long. This research is aimed to observe the efficiency of microcredit in the field of social exclusion. The development of questionnaires and use of existing tools was used to observe the tangible and intangible intertwining of microcredit and by doing so the effort was concentrated to observe whether microcredit has a direct effect on social exclusion or not. Bangladesh was chosen for the field study and 85 samples were taken for the analysis. It is a time period research and one year time was set to receive the sample and working on the statistical analysis. The tangible aspect was based on a World Bank questionnaire and the social capital questionnaire was developed through different well observed tools. The borrowers of Grameen Bank in Bangladesh, is the research sample whish shows a strong correlation between their tangible activity and social life. There are significant changes in tangible aspect and social participation observed from the research. Strong correlation between the two aspects was also found taking into account that the borrowers themselves have a vibrant social life in the village.

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Die beiden in dieser Arbeit betrachteten Systeme, wässrige Lösungen von Ionen und ionische Flüssigkeiten, zeigen vielfältige Eigenschaften und Anwendungsmöglichkeiten, im Gegensatz zu anderen Systemen. Man findet sie beinahe überall im normalen Leben (Wasser), oder ihre Bedeutung wächst (ioinische Flüssigkeiten). Der elektronische Anteil und der atomare Anteil wurden getrennt voneinander untersucht und im Zusammenhang analysiert. Mittels dieser Methode konnten die in dem jeweiligen System auftretenden Mechanismen genauer untersucht werden. Diese Methode wird "Multiscale Modeling" genannt, dabei werden die Untereinheiten eines Systems genauer betrachtet, wie in diesem Fall die elektronischen and atomaren Teilsystem. Die Ergebnisse, die aus den jeweiligen Betrachtungen hervorgehen, zeigen, dass, im Falle von hydratisierten Ionen die Wasser-Wasser Wechselwirkungen wesentlich stärker sind als die elektrostatischen Wechselwirkung zwischen Wasser und dem Ion. Anhand der Ergebnisse ergibt sich, dass normale nicht-polarisierbare Modelle ausreichen, um Ionen-Wasser Lösungen zu beschreiben. Im Falle der ionischen Flüssigkeiten betrachten wir die elektronische Ebene mittels sehr genauer post-Hartree-Fock Methoden und DFT, deren Ergebnisse dann mit denen auf molekularer Ebene (mithilfe von CPMD/klassischer MD) in Beziehung gesetzt werden. Die bisherigen Ergebnisse zeigen, dass die Wasserstoff-Brückenbindungen im Fall der ionischen Flüssigkeiten nicht vernachässigt werden können. Weiterhin hat diese Studie herausgefunden, dass die klassischen Kraftfelder die Elektrostatik (Dipol- und Quadrupolmomente) nicht genau genug beschreibt. Die Kombination des mikroskopischen Mechanismus und der molekularen Eigenschaften ist besonders sinnvoll um verschiedene Anhaltspunkte von Simualtionen (z.B. mit klassische Molekular-Dynamik) oder Experimenten zu liefern oder solche zu erklären.

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Eine zielgerichtete Steuerung und Durchführung von organischen Festkörperreaktionen wird unter anderem durch genaue Kenntnis von Packungseffekten ermöglicht. Im Rahmen dieser Arbeit konnte durch den kombinierten Einsatz von Einkristallröntgenanalyse und hochauf-lösender Festkörper-NMR an ausgewählten Beispielen ein tieferes Verständnis und Einblicke in die Reaktionsmechanismen von organischen Festkörperreaktionen auf molekularer Ebene gewonnen werden. So konnten bei der topotaktischen [2+2] Photodimerisierung von Zimt-säure Intermediate isoliert und strukturell charakterisiert werden. Insbesondere anhand statischer Deuteronen- und 13C-CPMAS NMR Spektren konnten eindeutig dynamische Wasserstoffbrücken nachgewiesen werden, die transient die Zentrosymmetrie des Reaktions-produkts aufheben. Ein weiterer Nachweis gelang daraufhin mittels Hochtemperatur-Röntgen-untersuchung, sodass der scheinbare Widerspruch von NMR- und Röntgenuntersuchungen gelöst werden konnte. Eine Veresterung der Zimtsäure entfernt diese Wasserstoffbrücken und erhält somit die Zentrosymmetrie des Photodimers. Weiterhin werden Ansätze zur Strukturkontrolle in Festkörpern basierend auf der molekularen Erkennung des Hydroxyl-Pyridin (OH-N) Heterosynthon in Co-Kristallen beschrieben, wobei vor allem die Stabilität des Synthons in Gegenwart funktioneller Gruppen mit Möglichkeit zu kompetetiver Wasserstoffbrückenbildung festgestellt wurde. Durch Erweiterung dieses Ansatzes wurde die molekulare Spezifität des Hydroxyl-Pyridin (OH-N) Heterosynthons bei gleichzeitiger Co-Kristallisation mit mehreren Komponenten erfolgreich aufgezeigt. Am Beispiel der Co-Kristallisation von trans--1,2-bis(4-pyridyl)ethylen (bpe) mit Resorcinol (res) in Gegenwart von trans-1,2-bis(4-pyridyl)ethan (bpet) konnten Zwischenprodukte der Fest-körperreaktionen und neuartige Polymorphe isoliert werden, wobei eine lückenlose Aufklärung des Reaktionswegs mittels Röntgenanalyse gelang. Dabei zeigte sich, dass das Templat Resorcinol aus den Zielverbindungen entfernbar ist. Ferner gelang die Durchführung einer seltenen, nicht-idealen Einkristall-Einkristall-Umlagerung von trans--1,2-bis(4-pyridyl)ethylen (bpe) mit Resorcinol (res). In allen Fällen konnten die Fragen zur Struktur und Dynamik der untersuchten Verbindungen nur durch gemeinsame Nutzung von Röntgenanalyse und NMR-Spektroskopie bei vergleichbaren Temperaturen eindeutig und umfassend geklärt werden.

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Il principale obiettivo della tesi è dimostrare come la connessione tra i differenti livelli giuridici che riguardano le relazioni tra Stati membri dell'UE richieda un'interpretazione sistematica delle convenzioni contro le doppie imposizioni intracomunitarie, ed in particolare richieda l'applicazione della clausola della nazione più favorita.

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Partendo da un’analisi di mercato che si sviluppa meglio con una segmentazione, andremo ad analizzare il settore degli editori di videogiochi, le loro quote di mercato e come si stanno evolvendo per rimanere al passo con la tecnologia in un settore con forte competizione. Lo scopo di questa tesi è spiegare il successo della Take Two Interactive descrivendo la sua storia, le strategia che ha adottato negli anni per arrivare a competere con altri grandi editori e come si sta approcciando alle nuove tecnologie, all’evoluzione dei comportamenti d’acquisto dei consumatori e ai nuovi mercati emergenti.

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Bei der Untersuchung molekularer magnetischer Materialien spielen Metall-Radikal Verbindungen eine bedeutende Rolle. Ein Forschungsschwerpunkt stützt sich auf die Familie der Nitronyl-Nitroxid (NIT) Radikale, die sich durch eine hohe chemische Stabilität auszeichnen. Im sogenannten „Metall-Radikal Ansatz“ wurden die starken Austauschwechselwirkungen zwischen stabilen Radikalen und Übergangsmetallionen in mehrdimensionalen Netzwerken ausgiebig untersucht. Um diese Netzwerke mit NIT Radikalen aufzubauen, müssen zusätzliche funktionelle Gruppen, mit einem Abstand zur spintragenden Einheit, in das Molekül eingebaut werden. Dies kann zu einer zusätzlichen schwachen Spinaustauschwechselwirkung führen. Um diese Wechselwirkung zwischen Metalldimeren mit einem einzelnen Benzoat annalogen NIT-Radikal zu untersuchen, wurden dimere Mangan(II), Kobalt(II) und Zink(II) Komplexe mit dem Chelatliganden N,N,N',N'-Tetrakis(2-benzimid-azolylalkyl)-2-hydroxy-1,3-diamino-propan synthetisiert und zusätzlich über eine periphere Carboxylat Gruppe eines NIT Radikals verbrückt.rnDie Messungen der magnetischen Suszeptibilität weisen auf eine dominante antiferromagnetische Wechselwirkung in der Metall-Radikal Verbindung hin, bei der es sich um die Spin-Austauschwechselwirkung innerhalb des Metalldimers handelt. Durch den Vergleich mit analogen Nitrobenzoat- verbrückten Mangan(II) und Kobalt(II) Verbindungen konnte gezeigt werden, dass keine Metall-Radikal Wechselwirkung beobachtet wird, obwohl eine Wechselwirkung der pi*-orbitale mit den delokalisierten pi-System des Phenylrings durch Spin-Polarisation grundsätzlich möglich ist. Auch ESR - Messungen bestätigen dies, da der Spingrundzustand das anisotrope Signal des freien NIT Radikals aufweist. Das Radikal verhält sich somit wie ein isoliertes S=1/2 Spin-Zentrum, was zusätzlich durch DFT-Rechnungen bekräftigt werden konnte. Zusammenfassend führt also die Koordination eines NIT-Benzoats an ein antiferromagnetisch gekoppeltes Metalldimer nur zur Anhebung des Spingrundzustandes und hat keinen signifikanten Effekt auf die Austauschwechselwirkung. Um trotzdem eine Metall-Radikal Wechselwirkung beobachten zu können, ist es notwendig Koordinationsverbindungen zu synthetisieren in denen hohe Spingrundzustände besetzt werden. Dies trifft auf das analoge Kupferdimer zu, wofür eine ferromagnetische Wechselwirkung zu beobachten ist.rnNach den Regeln der Spin-Polarisation müsste die Verkürzung des Austauschpfades um eine Bindung zu einer Umkehrung des Vorzeichens der magnetischen Wechselwirkung führen. Diese Verkürzung kann man durch die Verwendung des alternativen stabilen NOA-Radikals (tert-Butyl Nitroxid) erreichen. Sowohl das NIT als auch das NOA-Radikal werden an ein Kupfer(II)-dimer koordiniert, das durch die Verwendung des oben erwähnten N6O-Liganden gebildet wurde. In der Modellverbindung, ohne einen paramagnetischen Substituenten am Benzoat, zeigen die Kupferionen eine ferromagnetische Wechselwirkung mit einem Triplett Grundzustand, dessen Existenz durch die Messung der magnetischen Suszeptibilität und ESR-Spektroskopie belegt werden kann. Aufgrund der nahezu identischen Koordinationsumgebung bleibt bei allen synthetisierten Verbindungen die Kupfer-Kupfer Wechselwirkung dabei gleich. Die Daten von ESR und magnetischen Messungen zeigen weiterhin auf eine signifikante zusätzliche Metall-Radikal Wechselwirkung hin. Bei der NIT-Verbindung ist diese Austauschwechselwirkung schwach antiferromagnetisch, während die NOA-Verbindung eine schwache ferromagnetische Kopplung aufzeigt. Diese Resultate können durch DFT Rechnungen bekräftigt werden. Der Vorzeichenwechsel des Kopplungsparameters kann durch die Verkürzung des Austauschpfades vom NIT zum NOA-Benzoat um eine Bindung erklärt werden. Durch die Wahl von geeigneten Radikal- Liganden und Metallionen, zeigt sich die Möglichkeit, Systeme zu erzeugen, in denen die Radikal-Metall Wechselwirkung auch über größere Distanzen den Spin-Grundzustand des gesamten Systems signifikant beeinflussen kann. die Anwendung dieses Konzeptes auf Metall-Radikal Cluster System sollte Von großem Interesse sein.rn

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Il presente elaborato si prefigge l’obiettivo di verificare la reale e concreta applicazione delle disposizioni derivanti dall’ordinamento comunitario, all’interno della realtà portuale italiana, che, consapevole del fatto che i porti costituiscono forti infrastrutture nonché fonte di ricchezza per il paese, avverte l’esigenza di modificare fermamente il regime amministrativo dei propri porti. Le profonde innovazioni introdotte nel sistema portuale italiano a seguito della riforma del 1994, attraverso l’introduzione di assetti istituzionali ed organizzativi, hanno favorito la crescita dei traffici marittimi del paese. In ragione dei significativi mutamenti che hanno segnato la realtà economica mondiale negli ultimi anni, in cui si è assistito, al fenomeno della c.d. globalizzazione economica, che spinge verso la delocalizzazione produttiva e verso l’apertura di nuovi mercati di consumo, particolare attenzione è stata posta alle esigenze nascenti all’interno del sistema portuale, di apportare delle significative modifiche alla Legge 84/1994, per affrontare le nuove sfide poste dalla competizione comunitaria ed internazionale, e migliorare l’efficienza delle attività produttive ed uniformare l’impianto normativo. Nello specifico è stato esaminato il testo unificato della recente proposta di legge di riforma del settore portuale, le cui novità maggiormente rilevanti si sviluppano essenzialmente su tre livelli: la governance dei porti, la programmazione e la pianificazione delle aree, le attività economiche ed i servizi portuali. In maniera precisa e dettagliata, si è proceduto all’analisi dei servizi portuali tecnico-nautici, prestando attenzione alle prospettive di liberalizzazione del settore ed al principio di uniformità in materia tariffaria, al fine di rendere detti servizi funzionali e trasparenti. Infine, l’attenzione è stata posta alla realtà portuale a livello comunitario, esaminando le recenti disposizioni emanate dalle istituzioni comunitarie, al fine di verificare il miglior funzionamento dei porti marittimi e lo sviluppo della rete transeuropea di trasporto.

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I cicli di Hodge assoluti sono stati utilizzati da Deligne per dividere la congettura di Hodge in due sotto-congetture. La prima dice che tutte le classi di Hodge su una varietà complessa proiettiva liscia sono assolute, la seconda che le classi assolute sono algebriche. Deligne ha dato risposta affermativa alla prima sottocongettura nel caso delle varietà abeliane. La dimostrazione si basa su due teoremi, conosciuti rispettivamente come Principio A e Principio B. In questo lavoro vengono presentate la teoria delle classi di Hodge assolute e la dimostrazione del Principio B.

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This work is focused on the development of high quality nanoporous 1D photonic crystals –so called Bragg stacks – made by spin-coating of approximately 25 nm large SiO2 and TiO2 nanoparticles bearing interparticle voids large enough to infiltrate reactive species. Therefore, the first part of this work describes the synthesis of well-dispersed TiO2 nanoparticles in this size range (the corresponding SiO2 nanoparticles are commercially available). In the second part, a protocol was developed to prepare nanoporous Bragg stacks of up to 12 bilayers with high quality and precision. Tailor-made Bragg stacks were prepared for different applications such as (i) a surface emitting feedback laser with a FWHM of only 6 nm and (ii) an electrochromic device with absorption reversibly switchable by an external electrical bias independently of the Bragg reflection. In the last chapter, the approach to 1D photonic crystals is transferred to 1D phononic crystals. Contrast in the modulus is achieved by spin-coating SiO2 and PMMA as high and low moduli material. This system showed a band gap of fg = 12.6 GHz with a width of Dfg/fg = 4.5 GHz.

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Il mercato video ludico è stato, ed è tuttora uno dei settori più redditizi e innovativi del mercato globale. L’evoluzione tecnologica ha permesso lo sviluppo di device e piattaforme da gioco sempre più performanti e in grado di soddisfare le esigenze dei consumatori. Con le nuove prospettive di gioco ci si sofferma a riflettere su quale sarà l’evoluzione del business dell’intrattenimento interattivo. In questo elaborato andremo a vedere come si sta evolvendo il mercato dei videogiochi, quali sono i nuovi scenari competitivi che si sono affiancati a questo settore, quali sono i segmenti che stanno avendo una crescita considerevole negli ultimi 10 anni, e cercheremo di capire come cambierà il “gameplay” da salotto, quindi quali saranno le prospettive future delle console da gioco.