CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / Os compostos trans-[Co(cyclam)(SO3)(NCS)]Â4H2O, trans-[Ru(NH3)4(NCS)(SO4)] e trans-[(SO3)(cyclam)Co−NCS−Ru(NH3)4(NCS)](BF4), onde cyclam = 1,4,8,11-tetraazaciclotetradecano, foram sintetizados e caracterizados por difraÃÃes de raios-X, espectroscopias vibracional na regiÃo do infravermelho e eletrÃnica nas regiÃes do ultravioleta e visÃvel (UV-Vis) e por tÃcnicas eletroquÃmicas. O grau de comunicaÃÃo eletrÃnica entre os Ãtomos de Co e Ru do complexo binuclear foi avaliado por eletroquÃmica e espectroscopia eletrÃnica na regiÃo do infravermelho prÃximo. Apenas para o complexo trans-[Co(cyclam)(SO3)(NCS)]Â4H2O foi possÃvel a obtenÃÃo de cristais que permitiram a determinaÃÃo estrutural. Os dados obtidos indicam estrutura monoclÃnica com o ligante cyclam no plano equatorial e os ligantes SO32− e NCS− ocupando posiÃÃes trans e coordenados ao Ãtomo de Co atravÃs, respectivamente, dos Ãtomos de S e N. Este resultado à reforÃado atravÃs da observaÃÃo, no espectro vibracional, de bandas tipicamente atribuÃdas ao ligante cyclam quando este se encontra em uma geometria trans. Os resultados de voltametria cÃclica deste composto indicam um mecanismo eletroquÃmico-quÃmico-eletroquÃmico. De fato, os experimentos de espectroeletroquÃmica (potencial controlado em -0,80 V vs Ag/AgCl) indicam que este composto experimenta, apÃs reduÃÃo, reaÃÃo de substituiÃÃo das molÃculas SO32− e NCS− por molÃculas do solvente (L), formando compostos do tipo [Co(cyclam)(L)2]2+. A observaÃÃo, no espectro vibracional do complexo trans-[Ru(NH3)4(NCS)(SO4)], das bandas em 2132, 887 e 478 cm-1, atribuÃdas aos modos de νCN, νCS e δ(NCS), respectivamente, do ligante NCS−, indica a coordenaÃÃo deste grupo atravÃs do Ãtomo de nitrogÃnio. Estudos eletroquÃmicos e de espectroscopia eletrÃnica deste composto em meio aquoso indicam que a reduÃÃo do centro metÃlico induz a reaÃÃo de substituiÃÃo do ligante SO42− por uma molÃcula de H2O. A reaÃÃo para formaÃÃo do composto binuclear, portanto, foi realizada em condiÃÃes redutoras a fim de induzir a formaÃÃo do aquo-complexo de rutÃnio e, em seguida, a reaÃÃo de substituiÃÃo da molÃcula de H2O por um sÃtio de coordenaÃÃo do monÃmero trans- [Co(cyclam)(SO3)(NCS)]Â4H2O. Os resultados obtidos para o material isolado indicam que hà a formaÃÃo do complexo binuclear com o ligante NCS− ocupando a posiÃÃo ponte. A curva voltamÃtrica obtida para este composto apresenta dois pares de ondas redox com potenciais formais de meia-onda (E1/2) em −0,27 e 0,13 V vs Ag|AgCl atribuÃdos, respectivamente, aos centros metÃlicos de Co e Ru. Comparativamente aos monÃmeros, hà a observaÃÃo de um deslocamento positivo de potencial o que reflete a estabilizaÃÃo do estado reduzido para o Ãtomo de rutÃnio, RuII, e desestabilizaÃÃo do estado oxidado para o Ãtomo de cobalto, CoIII. Este resultado à atribuÃdo a coordenaÃÃo a um centro oxidado, CoIII, cuja carga nuclear efetiva aumenta a deslocalizaÃÃo de densidade eletrÃnica aumentando o carÃter retirador do ligante ponte NCS−. O valor da constante de comproporcionamento, Kc = 5,78 x 106, calculada a partir da diferenÃa entre os valores de E1/2, indica um forte grau de comunicaÃÃo entre os centros metÃlicos e classifica este complexo como um sistema de valÃncia mista de classe II. / Trans-[Co(cyclam)(SO3)(NCS)]Â4H2O, trans-[Ru(NH3)4(NCS)(SO4)], and trans-[(SO3)(cyclam)Co−NCS−Ru(NH3)4(NCS)](BF4) complexes, where cyclam = 1,4,8,11-tetraazacyclotetradecane, were synthesized and characterized by X-ray difraction, vibrational and electronic (ultraviolet, visible and near infrared) spectroscopies, and electrochemical techniques. The electronic communication between Co and Ru metal centers of the binuclear complex was evaluated by electrochemistry and electronic spectrocopy in the near infrared region. Crystals suitable for X-ray studies were only isolated for the trans-[Co(cyclam)(SO3)(NCS)]Â4H2O complex. The obtained results indicate a monoclic structure with cyclam ligand at the equatorial plane and SO32− and NCS− moieties occupying the axial positions being coordinated through, respectively, sulfur and nitrogen atoms. This result is reinforced by the observation, in the vibrational spectrum, of bands typically assigned to the cyclam ligand in a trans configuration. The cyclic voltammograms obtained for this compound indicate as Electrochemical-Chemical-Electrochemical mechanism. In fact, the spectroelectrochemical experiments obtained at -0.80 V vs Ag/AgCl show that this compound, upon reduction, suffers a substitution reaction in which the SO32− and NCS− moieties are replaced by solvent molecules (L) thus forming [Co(cyclam)(L)2]2+ type complexes. The observation in the vibrational spectrum of the trans-[Ru(NH3)4(NCS)(SO4)] complex of the 2132, 887 e 478 cm-1 bands assigned, respectively, to the νCN, νCS e δ(NCS) vibrational modes of the NCS− ligand indicates that this moiety is coordinated through the nitrogen atom. Electrochemical and spectroscopic studies of this compound in aqueous medium indicate that the reduction of the metal center induces the replacement of SO42− ligand by a water molecule. The synthesis of the binuclear compound, therefore, was made under reductive conditions aiming to produce the aquo-complex and, then, replace the water molecule by a coordination site of the trans-[Co(cyclam)(SO3)(NCS)]Â4H2O complex. The results obtained for the isolated material hints that the binuclear complex is formed with the NCS− fragment as the bridge ligand. The acquired cyclic voltammogram presents two redox process with the half-wave formal potentials (E1/2) observed at −0.27 and 0.13 V vs Ag|AgCl and being assigned to the Co and Ru metal centers, respectively. In comparison to the monomers, the positive potential shift reflects the stabilization of the reduced state of the ruthenium metal atom (RuII) and the destabilization of the cobalt metal center (CoIII). This result is assigned to the coordination to an oxidated metal center, CoIII, whose effective nuclear charge increased the electronic delocalization increasing the withdrawing character of the NCS− bridge ligand. The comproportionation constant, Kc = 5.78 x 106, was calculated from the difference between the E1/2 values. The Kc value indicates a strong electronic communication between the metal atoms and classifies this binuclear complex as a mixed valence system of class II.

FundaÃÃo de Amparo a Pesquisa do Estado de SÃo Paulo / Os complexos mononucleares, formados a partir das reaÃÃes do 1,3-bis(3-piridilmetil)-2-tiourÃia (BPMT) com os Ãons [Ru(NH3)5OH2]2+ e [Fe(CN)5NH3]3-, foram isolados e caracterizados por microanÃlise, espectroscopia eletrÃnica, vibracional na regiÃo do infravermelho, MÃssbauer e por tÃcnicas eletroquÃmicas (Voltametria cÃclica e voltametria de pulso diferencial). Nos complexos de pentaaminas de rutÃnio, foram evidenciadas maiores interaÃÃes de retrodoaÃÃo, dπ(M) → pπ*BPMT, que nos complexos de pentacianoferrato sendo justificada pela aÃÃo π - receptora dos Ãons cianeto e a diferenÃa de tamanho dos orbitais dos metais. Os complexos binucleares simÃtricos [(NH3)5Ru(μâBPMT)Ru(NH3)5](PF6)4, Na6[(CN)5Fe(μ â BPMT)Fe(CN)5].4H2O foram isolados e caracterizados por tÃcnicas espectroscÃpicas e eletroquÃmicas. CÃlculos das constantes de comproporcionamento indicaram que os compostos apresentam um considerÃvel acoplamento entre os centros metÃlicos, seguindo o comportamento dos complexos binucleares de classe II segundo a classificaÃÃo de Robin e Day. O complexo binuclear assimÃtrico Na6[(CN)5Fe(μâBPMT)Ru(NH3)5] foi sintetizado e caracterizado. Os valores dos potenciais de reduÃÃo seqÃencial de um elÃtron, as energias das bandas de transferÃncia de carga metal â ligante e o espectro vibracional na regiÃo do infravermelho indicam a existÃncia de um fraco acoplamento eletrÃnico entre os centros metÃlicos sugerindo que os Ãons cianeto comprometem consideravelmente as densidades eletrÃnicas do metal no fragmento pentacianoferrato. / Reactions of monocoordenative ions, such as [Ru(NH3)5(H2O)]2+ e [Fe(CN)5(NH3)]3-, with 1,3-bis(3-pyridylmethyl)-2-Thiourea (BPMT) lead to the formation of mononuclear complexes. Such complexes have been isolated and characterized by elemental analysis, electronic, vibrational in the infrared region, MÃssbauer spectroscopy and electrochemical techniques (Cyclic voltammetry and differential pulse voltammetry). Backdonation interactions, dπ(M) → pπ*BPMT, of ruthenium pentaammines complexes are greater than pentacianoiron (II), which shows the π â acceptor action of cyanide ligands and the small energy of 3d orbital compared with 4d. Symmetric binuclear complexes, [(NH3)5Ru(μâBPMT)Ru(NH3)5](PF6)4, Na6[(CN)5Fe(μâBPMT)Fe(CN)5].4H2O, have been also isolated and characterized by electrochemical and spectroscopic techniques. Evaluation of the comproportionation constants indicated that such complexes present a considerable coupling between the metallic centers, following the behavior of binuclear complexes of class II. Unsymmetrical binuclear complex Na[(CN)5Fe(μâBPMT)Ru(NH3)5] have been also synthesized and characterized. The values of the one â electron reduction potentials, the energies of the bands for metal â ligand charge transfer and the vibrational spectrum in the infrared region indicated a weak coupling between the metallic centers, which suggest that the cyanide ligands have a strong influence on the electronic density of the pentacyanoferrate complexes.

Abstract Electron-ion coincidence spectroscopy has been used to study the fragmentation behaviour of small molecules in two distinct cases: to resolve the state specific fragmentation patterns of HgBr₂ and HgCl₂ subsequent to UV ionization, and to distinguish the dissociation behaviour of various chlorinated methanes (CH₃Cl, CH₂Cl₂, CHCl₃ and CCl₄) subsequent to X-ray irradiation. The mercury-compound work has revealed details on the electronic structure and dissociation dynamics of the valence states which were previously unknown. The study on the chlorinated methanes has found new details on the exact pathways of the appearance of a specific fragment and also investigates the speed of the dissociation in the four different chlorinated methane molecules. The results from the electron-ion coincidence spectroscopic experiments are presented and analysed together with theoretical and computational support.

The aim of this research is to determine the extent to which the framing of information can reduce the persistence of misinformation. The overall research consists of two experiments of which the first has been conducted and is described in this paper. It investigates the strength of differently framed statements and the degree to which the regulatory focus fit the participants experienced influenced their preference for certain statements. 52 participants have completed the survey in which they were presented several statements containing the same facts but framed differently based on the principles of valence message framing. The research found the positive goal frame, positive valence frame and the company s original statement to be most effective. These statements will form the basis for the second experiment which aims to combine the different frames in such a manner that the continued influence effect will be reduced.

Enantioselective reactions are one of the ways to produce pure chiral compounds. Understanding the basis of this selectivity makes it possible to guide enzyme design towards more efficient catalysts. One approach to study enzymes involved in chiral chemistry is through the use of computational models that are able to simulate the chemical reaction taking place. The potato epoxide hydrolase is one enzyme that is known to be both highly enantioselective, while still being robust upon mutation of residues to change substrate scope. The enzyme was used to investigate the epoxide hydrolysis mechanism for a number of different substrates, using the EVB approach to the reaction both in solution and in several enzyme variants. In addition to this, work has been performed on new ways of performing simulations of divalent transition metals, as well as development of new simulation software.

Syftet med studien var att undersöka hur ett internt meddelande uppfattas av mottagaren, beroende på om meddelandet är positivt eller negativt, samt om det finns skillnad i mottagandet av meddelandet när det är strikt faktabaserat alternativt framfört med ett narrativt berättande. Digitala enkäter skickades till mottagare via sociala medier. Enkäten innehöll fyra olika texter, två meddelanden var narrativt utformade och två strikt faktabaserade. Frågorna i enkäten var utformade för att besvara om mottagandet påverkas av textstatus (retoriskt vs fakta), samt om skillnader fanns mellan valens (positivt vs negativt laddat meddelande). Mottagandet mättes på en likertskala utifrån dimensionerna öppenhet, förståelse och tydlighet. Resultatet visar på att retoriskt berikade meddelanden tagits emot bättre i alla tre dimensionerna, oberoende om budskapet var positivt eller negativt. / The purpose of the study was to investigate how a written internal message is perceived by a recipient depending on whether the message is phrased positive or negative, and whether the message is strictly fact-based or presented in a narrative. This study was conducted through digital surveys which were sent to the recipient via social media. The questionnaire contained four different texts, two messages were presented in a narrative and two were strictly fact-based. Further, the messages are designed in the way that two messages have a negative message and the other two are designed with positive messages. The questions in the survey are designed to answer whether the reception is affected by text status (rhetorical vs. factual) and whether differences exist between the valence (positive vs. negatively charged message). Reception was measured on a Likert scale based on the dimensions of openness, understanding and clarity. The result shows that the rhetorically enriched message was better received, regardless of whether the message was positive or negative.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22277号 / 理博第4591号 / 新制||理||1659(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 北川 宏, 教授 竹腰 清乃理, 教授 吉村 一良 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

No description available.

The goal of this research is to develop Animated Pedagogical Agents (APA) that can convey clearly perceivable emotions through speech, facial expressions and body gestures. In particular, the two studies reported in the thesis investigated the extent to which modifications to the range of movement of 3 beat gestures, e.g., both arms synchronous outward gesture, both arms synchronous forward gesture, and upper body lean, and the agent ‘s gender have significant effects on viewer’s perception of the agent’s emotion in terms of valence and arousal. For each gesture the range of movement was varied at 2 discrete levels. The stimuli of the studies were 8 12-seconds animation clips generated using a fractional factorial design; in each clip an animated agent who speaks and gestures, gives a lecture segment on binomial probability. 4 clips featured a female agent and 4 clips featured a male agent. In the first study, which used a within-subject design and metric conjoint analysis, 120 subjects were asked to watch the 8 stimuli clips and rank them according to perceived valence and arousal (from highest to lowest). In the second study, which used a between-subject design, 300 participants were assigned to two groups of 150 subjects each. One group watched the 4 clips featuring the male agent and one group watched the 4 clips featuring the female agent. Each participant was asked to rate perceived valence and arousal for each clip using a 7-point Likert scale. Results indicated that extending the arms outwards and forwards as well as modifying the agent’s gender from male to female increased perceived valence and arousal, whereas rotating the body backwards increased only perceived valence.

When regarding the history of role theory, one becomes aware of the fact that, although much knowledge is available specifically pertaining to roles in small group settings (e.g. expectations about behaviour, types of roles, flexibility of locus, appropriateness of the role system, dynamic nature of role formation and development as well as typologies dividing roles into categories), not much literature is available specifically pertaining to what the impact of an individual’s self-concept is on his/her propensity to either assume or avoid certain roles in such a setting. Accordingly, this study aimed to explore the above-mentioned aspect of role division in small groups. Research was done by means of a case study research design, with a constructivist/interpretevist meta-theoretical paradigm as research approach. This paradigm holds that there are multiple subjective realities involved when studying human interactions and the consequences thereof. The study was furthermore conducted from a psychodynamic and systems theory perspective. Data was collected from a sample of postgraduate students, who participated in a training group as part of their Industrial and Organisational Psychology master’s degree programme at the University of Pretoria, by means of three different methods, namely video and voice recordings, a document study, as well as semi-structured interviews. Data was furthermore analysed by Atlas.ti, a qualitative data analysis programme, according to the principles of constructivist grounded theory. When regarding current literature on the subject, it is implied by some that an individual will only allow roles to be imposed on him/her if he/she is predisposed to assuming such roles, and if he/she can accordingly integrate the responsibility somehow with his/her self-concept. Accordingly, the results obtained showed some connection between an individual’s self-concept and the role(s) that was assumed by the individual in the small group setting. More specifically, the results showed that an individual is more likely to change roles with ease should the alternate role requirements also be in line with elements of the individual’s self-concept. The results further indicated that it might be difficult for an individual to adapt and change to another role should the roles, which are required in the small group setting, be in conflict with the individual’s self-concept. These findings thus imply that an individual’s self-concept might have an impact on an individual’s propensity to either assume or avoid certain roles (role valency) in a small group setting. / Dissertation (MCom)--University of Pretoria, 2011. / Human Resource Management / unrestricted