published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

This dissertation describes the experimental study of the electronic-structural relationships of selected mononuclear transition-metal sulfur dioxide, cyclopentadienyl and carbonyl complexes and the application of the information gained from these to the study of quadruply-bonded dimetallic complexes. These pertinent observations result from the application of photoelectron spectroscopy (p.e.s.) as a probe into the bonding, charge-distribution and excited state effects which contribute to the specifics of the ground and excited state molecular structures. The first part of this discussion centers around a specific study of the exemplary bonding probe, SO₂, with the well characterized ArM(CO)₂ metal fragment, where Ar = Bz and Cp and M = Cr, Mn and Re. A comparison of the ionization information with the structural details and molecular orbital calculations reveals not only the surprising coordinating similarity of SO₂ and CO in these complexes, but also the electronic origin for the counter-intuitive SO₂ bonding configuration. This work then moves to a more dramatic example of electronic control of ground state molecular structure; the crystallographically determined distortion of the coordinated Cp ring in Cp*Rh(CO)₂. The electronic origin of this distortion is graphically shown with the aid of two and three dimensional experimental and theoretical electron density maps. The structural effects of removing bonding electrons from quadruply-bonded dimetallic complexes is then investigated. This study incorporates the use of high-resolution p.e.s. for the novel observations of metal-metal vibrational structure in the predominantly metal ionizations providing direct information of the bonding influence of specific metal electrons. Particular attention is focused on the delta-ionization process of MO₂(O₂CCH₃)₄. The final chapter presents a comprehensive study of the valence and core ionizations of the series of quadruply-bonded M₂(X₂CR)₄ complexes, where M₂ = Cr₂, Mo₂, MoW, and W₂, X = O and S, and R = H, CH₃, CD₃, CF₃, CH₂CH₃, CH₂CH₂CH₃ and C(CH₃)₃. The changes in the electronic structure in both the ground and excited states of these molecules is presented and, where appropriate, compared to structural changes. The study of this series not only demonstrates how p.e.s. can be used to monitor the electronic effects of specific chemical modifications, but also reveals surprising excited state features related to facile charge-reorganization processes.

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Sėkmingam įvairių pratimų ir jų kombinacijų atlikimui labai svarbi koordinacija. 8 – 10 metų gimastės dar sunkiai jaučia muzikos tempo pagreitėjimą ir sulėtėjimą, reikiamu metu sunkiai sutelkia dėmesį bei ne visada greitai greitai įvertina situaciją. Visą tai jos turi susikoncentravusios atlikti meninė gimnastikos šokio metu tik per 1 min. 30 s. Visa tai šiek tiek panašu i estafečių atlikimą su įvairiais įrankiais per kuo trumpesnį laiką. Matydami šią problemą, manome, jog būtų tikslinga parengti estafečių kompleksus, lavinančius koordinacinius gebėjimus. Tyrimo tikslas: Ištirti 8-10 metų mergaičių koordinacinių gebėjimų lavinimo aspektus, taikant estafečių variantus per meninės gimnastikos pratybas. Tyrimo tikslo įgyvendinimo metodai: literatūros analizė, pedagoginis eksperimentas, testavimas, matematinės statistikos metodai. Eksperimentinės programos sudarytų estafečių kompleksų turinį sudarė bėgimo su kaspinais ir be jų, kamuolių varymo, gimnastikos šuolų su šokdynėmis ir be jų, šuolių pro lankus, statinė pusiausvyra, akrobatiniai ir kiti neįprasti pratimai. Testavome kai kurių fizinių ypatybių, o plačiau atskirų koordinacinių gebėjimų lygį tyrimo pradžioje ir pabaigoje. Eksperimento pradžioje visi gauti tyrimų rezultatai buvo statistiškai nepatikimi (3 lentelė). E1 grupės mergaitės kas antrą treniruotę, užsiėmimų pabaigoje buvo suskirstytos į dvi grupes, ir bėgo keturias skirtingo turinio estafetes. Jos efektingai pagerino šios grupės mergaičių koordinacijos gebėjimų... [toliau žr. visą tekstą] / To the succesful performance of different combinations and exercises very important is coordination. For 8 - 10 years gimnasts still hard to feel the music tempo acceleration and deceleration, at the appropriate time hardly focuses their attention quickly and not always quickly assess the situation - flight of the tool path, the balance suport. All this is concentrated in the rhytmic gymnastics dance at just 1 min. 30 sec. Seeing this problem, we believe that it would be appropriate to prepare a relay of complexes training coordination skills at early age. Research purpose: analyse coordinating skills develpment peculiarity of 8-10 years old girls during the rhythmic gymnastics practical training. Research purpose methods: pedagogical experiment, the testing, mathematical statistics methods, analysis of literature. Experimental program relayed the contents of running with or without ribbons, balls, gymnastic jumps with and without ropes, jumps through hoops, static balance, acrobatic and other unusual exercises. We tested certain physical features, and more widley coordination of individual skills levels at the beginning and end of the experiment. At the beginning of the experiment all test results were unreliable (3 table). E1 group girls every second training at the end of it were divided into two groups, and ran four relays with different content. They had efectively improved coordination skills, physical features results during the experimental period, but only the... [to full text]

Metal-organic frameworks (or coordination polymers) are a recently-identified class of porous polymeric materials, consisting of metal ions or clusters linked together by organic bridging ligands. The major advantage of MOFs over other traditional materials, such as zeolites or activated carbons, is that their synthesis methods have provided an extensive class of crystalline materials with high stability, tunable metrics, and organic functionality. The ability to modify the physical environment of the pores and cavities within MOFs allow tuning of the interactions with guest species, and serves as a route to tailor the chemical stability and/or reactivity of the frameworks for specific applications. The classical way to incorporate functional groups into a MOF is the modification of the organic precursor with specific substituents before synthesizing the MOF itself; we call this approach pre-functionalization method. Functionalization of organic precursors is the initial and necessary step to obtaining functionalized isostructural MOFs and also provides the possibility for the post-synthetic modification of MOFs. However, in some cases, the functional groups may interfere with MOF synthesis and alter the topology of desired MOF. The goal of this proposed research is to explore the possibilities of metal-organic frameworks (MOFs) as novel porous structures, to study the effect of functional groups on the topologies and adsorption behavior of MOFs, and to understand how the synthesis conditions affect the phase purity and the in-situ reaction of ligands.

This thesis investigates the mechanisms underlying the formation, maintenance, and sharing of reference in tasks in which language and vision interact. Previous research in psycholinguistics and visual cognition has provided insights into the formation of reference in cross-modal tasks. The conclusions reached are largely independent, with the focus on mechanisms pertaining to either linguistic or visual processing. In this thesis, we present a series of eye-tracking experiments that aim to unify these distinct strands of research by identifying and quantifying factors that underlie the cross-modal interaction between scene understanding and sentence processing. Our results show that both low-level (imagebased) and high-level (object-based) visual information interacts actively with linguistic information during situated language processing tasks. In particular, during language understanding (Chapter 3), image-based information, i.e., saliency, is used to predict the upcoming arguments of the sentence, when the linguistic material alone is not sufficient to make such predictions. During language production (Chapter 4), visual attention has the active role of sourcing referential information for sentence encoding. We show that two important factors influencing this process are the visual density of the scene, i.e., clutter, and the animacy of the objects described. Both factors influence the type of linguistic encoding observed and the associated visual responses. We uncover a close relationship between linguistic descriptions and visual responses, triggered by the cross-modal interaction of scene and object properties, which implies a general mechanism of cross-modal referential coordination. Further investigation (Chapter 5) shows that visual attention and sentence processing are closely coordinated during sentence production: similar sentences are associated with similar scan patterns. This finding holds across different scenes, which suggests that coordination goes beyond the well-known scene-based effects guiding visual attention, again supporting the existence of a general mechanism for the cross-modal coordination of referential information. The extent to which cross-modal mechanisms are activated depends on the nature of the task performed. We compare the three tasks of visual search, object naming, and scene description (Chapter 6) and explore how the modulation of cross-modal reference is reflected in the visual responses of participants. Our results show that the cross-modal coordination required in naming and description triggers longer visual processing and higher scan pattern similarity than in search. This difference is due to the coordination required to integrate and organize visual and linguistic referential processing. Overall, this thesis unifies explanations of distinct cognitive processes (visual and linguistic) based on the principle of cross-modal referentiality, and provides a new framework for unraveling the mechanisms that allow scene understanding and sentence processing to share and integrate information during cross-modal processing.

This thesis aims to contribute to the body of work that seeks to unpack development by asking: how does development work? Using a purposive case study of Uganda and taking a mixed methods approach, the thesis explores the reality behind the rhetoric of aid coordination in a developing health sector, questioning the premise that coordination is pursued exclusively to improve the efficacy of official development assistance (as inferred by partners‟ vocal commitments to the tenets of the Paris Declaration on Aid Effectiveness). The study focuses on the member groups currently empowered to join Uganda‟s most important multi-stakeholder forum for health - the Health Policy Advisory Committee - finding that all members are guilty of picking and choosing from a checklist of voluntary coordination commitments. This is found to be at once logical - for facilitating the semblance of partnership between a disparate grouping of stakeholders with differing modi operandi, agency objectives and tolerance for risk – and advantageous - for masking difference and allowing outwardly homogenous groupings like the Health Development Partners to speak with “one voice” when addressing the Ugandan government. Most importantly of all however, partial adherence to the aid coordination ethos is found to permit the framing that aid to Uganda is at once necessary and well targeted, as the Government of Uganda actively invites its partners to participate in the processes of government at the central level. Such tangible commitments to the tenets of partnership and transparency are integral to maintaining donor confidence in the aftermath of two financial scandals involving the Global Fund for AIDS, Tuberculosis and Malaria and the Global Alliance for Vaccines and Immunisation in 2005. In sum, the thesis argues that while on the surface coordination appears important for its internal significance - as an organising principle to improve the effectiveness of aid - in fact, the value of coordination stems from its external significance. Coordination creates a façade of unity which permits the continuance of aid flows to Uganda, with coordination activities now playing a pivotal role in determining who gives and receives aid, and how it should be spent.

The thesis analyses how NGOs define the meaning of civil society in Namibia through their everyday work. Based on 12 months fieldwork at the national umbrella for NGOs the thesis shows that this definition was mainly shaped by NGOs’ administration of the everyday rather than the outcome of ideological debates about how to “do good”. The thesis examines how dominant NGO practices reflect the basic tension between NGOs’ activists claims and the bureaucratic reality of their work and in doing so speaks to debates about NGO agency, accountability and their relevance for development. The thesis shows how organisations use formal criteria in reporting, networking, advocacy, fundraising and branding to continuously redefine what activism ought to be about and how “proper” civic organisations ought to behave. NGOs write reports to enhance their accountability and transparency, but the correct reporting form also delineates what counts as proper civic activism. They present networking as civil society’s main coordinating mechanism, but meetings always call for more coordination and hence additional meetings. Advocacy does not only concern the relations between civic organisations and the government, but NGOs also use these relations to justify surveillance and control within civil society. Competitive fundraising does not blindly follow donors’ demands, rather, through it NGOs create a canon of fundable and thus legitimate projects. Finally, the branding of civic activism is not simply concerned with the promotion of civil society organisations, but is seen as an attempt to create a unified corporate image with a sharp distinction between proper and improper civic activism. Struggles over meaning are therefore shifted into contestations around technicalities. The administration of the everyday in civil society thus becomes the prime means to decide how to “do good”.