The new and forthcoming generation of mobile networks intend to operate at considerably higher frequencies than the previous systems. This lift in frequency of operation alleviates today’s communication systems’ crowded bandwidth and allows for faster data rates than previously possible. However, the suggested increase in frequency of operation introduces new challenges and new antenna solutions are required. One possible candidate for the future communication systems is the Luneburg lens antenna that offers high gain, a simple feeding network and wide-angle scanning. Scanning of lens antennas occurs by placing several feeds along its focal line, but where the width size of the feed place a major constraint on the achievable crossover level between beams. In this thesis, we aim to increase the crossover level between beams in a geodesic Luneburg lens antenna. The importance of a high crossover level is to ensure a more equal performance in terms of data rate transfer to all end users. Here, we investigate two different methods on achieving a higher crossover level. The first method is to utilize a near-field lens while the other method concerns the usage of a generalized Luneburg lens that allows to displace the focal point outside the lens’ contour. A comparison study of these two alternatives are made where it is shown that a generalized Luneburg lens is the preferable choice. A generalized geodesic Luneburg lens is thereafter designed that attains a crossover level of -3:87 dB at the central frequency 62 GHz for the center port. The lens performs well with a bandwidth of 15% and a scanning range between ±52°. The reflection coefficient is below -13 dB in the frequency range of interest and the cross-talk is below -17:9 dB. The realized gain is simulated to 19:01 dBi at 57 GHz, 20:85 dBi at 62 GHz and 21:34 dBi at 67 GHz for the central port. / Den nya och de kommande generationerna av mobilnät avser att fungera på betydande högre frekvenser än tidigare system. Det här lyftet i frekvens minskar den trånga bandbredden i dagens kommunikationssytem och tillåter för snabbare datahastigheter än tidigare möjligt. Däremot, den förslagna ökningen av frekvens introducerar nya utmaningar och därmed behövs nya antennlösningar. En möjlig kandidat för det framtida kommunikationssystemet är Luneburg linsantennen som erbjuder en hög antennförstärkning, ett enkelt matningsnätverk och en bred vinkelskanning. Vinkelskanning av linsantenner sker genom att placera flera matningar längs dess fokallinje, men där bredden på matningarna utgör en stor begränsning för den nåbara korsningsnivån mellan strålningsfält. Det här examensarbetets syfte är att öka korsningsnivåerna mellan strålningsfälten i en geodetisk Luneburg linsantenn. Betydelsen att ha höga korsningsnivåer mellan strålningsfält är att säkerhetsställa en mer jämn prestanda av datahastigheter för alla slutanvändare. Vi undersöker två olika metoder för att uppnå högre korsningsnivåer. Den första metoden använder en närfältslins medan den andra metoden använder sig av en generaliserad Luneburg lins som tillåter att förflytta fokalpunkten utanför linsens kontur. En jämförelsestudie mellan dessa två metoder är genomförd där det visas att den generaliserade Luneburg linsen är det fördelsaktiga valet. En generaliserad Luneburg lins är därefter designad som uppnår korsningsnivåer på -3:87 dB på den centrala frekvensen 62 GHz för center porten. Linsen fungerar väl med en bandbredd på 15% och vinkelskanning mellan ±52°. Reflektionskoefficienten är under -13 dB i frekvensområdet av intresse och kopplingen mellan olika portar är under -17:9 dB. Den realiserade antennförstärkningen är simulerad till 19:01 dBi vid 57 GHz, 20:85 dBi vid 62 GHz och 21:34 dBi vid 67 GHz.

Objectif. Les jeunes crossover sont définis comme des adolescents qui sont à la fois victimes de maltraitance et délinquants juvéniles. L'objectif de ce mémoire est d’examiner les relations entre les paramètres de la maltraitance (ex., récurrence, sous-types et variété) et les paramètres de la délinquance juvénile (ex., précocité, volume, variété, gravité moyenne et présence de sous-types) vécus par les jeunes crossover. Méthodes. La source des données est constituée de rapports officiels pour tous les adolescents et adolescentes québécois qui ont plaidé coupables ou ont été reconnus coupables d'un crime entre le 1e janvier 2005 et le 31 décembre 2010. D'abord, un portrait des jeunes crossover québécois est dressé à l’aide de statistiques descriptives. Ensuite, des analyses multivariées sont utilisées pour déterminer si les paramètres de la maltraitance prédisent les différentes dimensions de la délinquance et pour examiner les différences selon le sexe. Résultats. La délinquance des jeunes crossover est plus importante que celle des délinquants non-maltraités. Les expériences différentielles de la maltraitance sont liées à des paramètres hétérogènes de la délinquance juvénile. La récurrence de la maltraitance est un prédicteur important des paramètres de la délinquance ultérieure. De plus, la maltraitance est particulièrement influente sur la délinquance des garçons. Implications. Les interventions au sein des systèmes de la protection de la jeunesse et de la justice juvénile doivent être adaptées afin d'identifier les jeunes à risque de délinquance grave, de cibler les dimensions spécifiques de la maltraitance et d’entraver leurs liens à la délinquance ultérieure. L'intervention doit être privilégiée pour les victimes de multiples incidents de maltraitance et pour les garçons victimes de maltraitance. / Objective. Crossover youth are defined as youth who are both victims of maltreatment and juvenile offenders. The objective of this thesis to shed light on the associations between the parameters of maltreatment (i.e., recurrence, subtypes and variety) and the parameters of juvenile delinquency (i.e., precocity, volume, variety, average severity and presence of subtypes) experienced by crossover youth. Methods. The data source is comprised of official records for the population of Quebec male and female adolescents that pled guilty or were convicted of a crime between January 1st 2005 and December 31st 2010. First, descriptive statistics are utilized to draw a portrait of crossover youth in Quebec. Second, multivariable analyses are used to determine whether the parameters of maltreatment predict different dimensions of delinquency and to examine possible sex differences. Findings. Crossover youth demonstrate more serious delinquency than non-maltreated offenders and differential exposure to maltreatment is linked to heterogeneous parameters of juvenile delinquency. The recurrence of maltreatment emerges as an important predictor of the parameters of subsequent offending. Moreover, maltreated boys demonstrated more problematic indicators of juvenile delinquency than maltreated girls. Implications. Interventions within the youth protection and juvenile justice systems should be tailored in order to identify youth at-risk for serious delinquency, to target specific dimensions of maltreatment and to potentially hamper their link to subsequent offending. Intervention should be privileged for victims of multiple incidents of maltreatment and for maltreated boys.

Recently, we have described the synthesis of chiral metal–organic frameworks iPr-ChirUMCM-1 and Bn-ChirUMCM-1 and their use in enantioselective separation. Here, we demonstrate for the first time the use of a chiral solvating agent (1-phenyl-2,2,2-trifluoroethanol, TFPE) for chiral recognition in iPr-ChirUMCM-1 and Bn-ChirUMCM-1 by means of solid-state13C NMR spectroscopy. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

This thesis deals with solving of the Rubik's cube. It describes the Rubik's cube and the famous methods for its composition. The main goal of this work is to propose an evelutionary method that for any configuration of blocks will lead to its composition. The theis describes the problem encoding, the proposed evelutionary algorithm and its proper configuration and deployment. The achieved results are commented on and compared with other known mehtods in conclusions.

Recently, we have described the synthesis of chiral metal–organic frameworks iPr-ChirUMCM-1 and Bn-ChirUMCM-1 and their use in enantioselective separation. Here, we demonstrate for the first time the use of a chiral solvating agent (1-phenyl-2,2,2-trifluoroethanol, TFPE) for chiral recognition in iPr-ChirUMCM-1 and Bn-ChirUMCM-1 by means of solid-state13C NMR spectroscopy. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Die vorliegende Arbeit thematisiert Eisen(II)-Komplexe mit Spinübergangseigenschaften. Dafür wurden neue hexadentate Liganden auf Basis von N,N'-Bis(2,2'-bipyridin-6-ylmethyl)-2,2'-biphenylendiamin entwickelt. Die in Kapitel 3.1 vorgestellten Systeme variieren dabei in den jeweiligen Substituenten der 6,6‘-Positionen der Biphenyleinheit. Es wird der Einfluss dieser Gruppen auf die magnetischen Eigenschaften der resultierenden Komplexe gezeigt. Im darauffolgenden Kapitel 3.2 wird ein variiertes Ligandensystem vorgestellt, in welchem anstelle einfacher Substituenten Donorfunktionen eingeführt wurden, sodass ein symmetrischer dinuklearer Eisen(II)-Komplex zugänglich war. In diesem sind die beiden Spin Crossover (SCO) Zentren erstmalig durch eine Biphenyleinheit verbrückt. Die durchgeführten Untersuchungen geben Hinweise auf eine allostere Wechselwirkung. Weiterhin wurde der Ligand durch N-Methylierung in ein tertiäres Amin überführt und die entsprechenden Komplexe mit Fe(II), Co(II) und Zn(II) synthetisiert (Kapitel 3.3). Diese wurden strukturell und elektrochemisch untersucht und hinsichtlich ihrer Redoxeigenschaften und Magnetismus mit den Komplexen der sekundären Amine verglichen. Ebenfalls wurde das Grundgerüst des auf sekundären Aminen basierenden Liganden so variiert, dass der terminale Donor durch stickstoffhaltige Fünfringheterocyclen – anstelle von Pyridin – verkörpert wurde (Kapitel 3.4). So konnten Eisen(II)-SCO Komplexe erhalten werden, welche eine wesentlich niedrigere Übergangstemperatur aufwiesen und somit magnetische Untersuchungen im Festkörper sowie des Photomagnetismus ermöglichten. Schließlich wurden neue tridentate Amine (2-(6-R-Pyridin-2-yl)-1,10-phenanthrolin) und deren Eisen(II)-Komplexe synthetisiert (Kapitel 3.5). Für einige dieser Komplexe konnte bereits das Spin Crossover Verhalten in Lösung untersucht werden. / The present thesis addresses iron(II) complexes with spin transition properties. For this purpose new hexadentate ligands were developed on the basis of N,N’-bis(2,2’-bipyridine-6-ylmethyl)-2,2’-biphenylenediamine. The systems introduced in chapter 3.1 vary in respect to the substituents in the 6,6’-positions of the biphenyl unit. The influence of these varying moieties on the magnetic behavior of the resulting complexes is shown. In the following chapter 3.2 a tuned ligand system is introduced, in which the substituents are donor functions so that a symmetrical dinuclear iron(II) complex was feasible. In this the two Spin Crossover (SCO) centers are for the first time connected by a biphenyl core. The executed experiments give hints to an allosteric interaction in this dinuclear compound. Moreover the ligand was reacted by N-methylation yielding a tertiary amine and the corresponding complexes with Fe(II), Co(II) and Zn(II) were synthesized (chapter 3.3). Those were investigated structurally and electrochemically and were then compared with the complexes with secondary amines in respect to their redox and magnetic properties. The ligand motif based on secondary amines was also modified in a way that the terminal donor was represented by nitrogen based five-ring heterocycles instead of pyridine (chapter 3.4). So iron(II) SCO complexes were available which showed much lower thermal transition temperatures and thus magnetic investigations in the solid state as well as investigations on the photomagnetic properties became possible. Ultimately, novel tridentate amines (2-(6-R-pyridine-2-yl)-1,10-phenanthroline) and the corresponding iron(II) complexes were synthesized (chapter 3.5). For some of those complexes the spin transition could already be monitored in solution.

[pt] Investiga-se a presença, na literatura infantil, de temas fortes como solidão, abandono e destruição ambiental como modo de evidenciar e discutir a porosidade de leituras que permitem tanto o adulto quanto a criança coabitarem espaços potencializadores do sensorial (olhar, escutar, tocar), atravessando-os como fluxos que eclodem em experiências que transbordam para além do contato com o livro. A dissertação reúne os livros Por parte de pai, de Bartolomeu Campos de Queirós; Um dia, um rio, de Leo Cunha com ilustrações de André Neves e Rosa, de Odilon Moraes e estabelece pontos de contato entre estes e textos teóricos com a intenção de diluir fronteiras, sejam elas em termos de público (infantil/adulto) ou de experiências, compondo, assim, uma literatura infantil que se revela cada vez mais complexa e multifacetada. Para isso, as referências crítico-teóricas são constituídas por autores que pesquisam sobre literatura infantil como Teresa Colomer, Nelly Novaes Coelho, Peter Hunt, Sandra Beckett, e de autores como Walter Benjamin, Deleuze e Guattarri, tecendo uma trama que tem a intenção de fomentar um pensamento crítico com amplitude suficiente para abarcar a complexidade dos objetos analisados. / [en] The presence in children s literature of hard themes such as loneliness, abandonment and environmental destruction is investigated, as a way of underline and discuss the porosity of the readings, that allow either the adult and the child to cohabit spaces for mighting sensorial experimentation (look, listen, touching), traversing them as streams that hatch into experiences that unveil beyond contact with the book. The dissertation combines the books Por Parte de Pai, by Bartolomeu Campos de Queirós; Um dia, um Rio, by Leo Cunha and illustrated by André Neves and Rosa, by Odilon Moraes and establishes contact points between these books and theoretical texts with the intention of diluting borders, be in terms of public type (children/adults) or experiences, thus composing a children s literature that is increasingly complex and multifaceted. For this, the critical-theoretical references are constituted by authors who research on children s literature as: Teresa Colomer, Nelly Novaes Coelho, Peter Hunt, Sandra Beckett, and authors such as: Walter Benjamin, Deleuze and Guattarri, weaving a plot that has the intention to create critical thinking with enough breadth to cover the complexity of the analyzed objects.

We studied the structural instabilities of one-dimensional (1D) and quasi-one-dimensional (Q1D) electron-phonon systems at low temperature through two models, SuSchrieffer-Heeger (SSH) and molecular crystal (CM) with and without spin. The phase diagrams are obtained using a Kadanoff-Wilson renormalization group approach (GR). For the 1D half-filled system the study of the frequency dependence of the electronic gap allowed us to connect continuously the two limits, adiabatic and non-adiabatic. The Peierls and Cooper channels interference and the quantum fluctuations reduce the gap. A regime change occurs when the frequency becomes of the order of mean field gap, marking a quantum-classical crossover that is the Kosterlitz-Thouless type. At this level, the effective coupling behaves in power law function on frequency. For the case with spin, a gapped Peierls state is maintained in the non-adiabatic limit, while for the case without spin, the system transits to ungapped disordered state, namely the Luttinger liquid stat (LL). For the SSH model without spin, the GR confirms the existence of a threshold phonon coupling beyond which the gap is restored. The study of the rigidities of the two models without spin allowed us to trace the main features of the LL state predicted by the bosonization method. The study of the Holstein-Hubbard model has allowed us not only to reproduce the phase diagrams already obtained by the Monte Carlo method, but to highlight two additional phases, namely, free fermions phase and the bond charge-density-wave phase. We have extended this study to the quarter-filled Q1D Peierls systems at finite temperature. Within the SSH model, an unconventional superconducting phase with spin singlet symmetry SS-s emerges at low temperature when the deviation to the perfect nesting of the Fermi surface is strong enough. Peierls-SS transition is characterized by the presence of a quantum critical point at low frequency and by a power law behavior of the transition temperature as a function of frequency with an exponent identical to one of 1D system. This exponent which universality has been verified contrasts with the BCS result. Coulomb interactions have been introduced through the study of the extended SSH-Hubbard model. The extension of this work to half-filled SSH and CM cases was also performed.

A series of Fe2+ spin crossover (SCO) complexes [Fe(5/6)]2+ employing hexadentate ligands (5/6) with cis/trans-1,2-diamino cyclohexanes (4) as central building blocks were synthesised. The ligands were obtained by reductive amination of 4 with 2,2′-bipyridyl-6-carbaldehyde or 1,10-phenanthroline-2-carbaldehyde 3. The chelating effect and the rigid structure of the ligands 5/6 lead to exceptionally robust Fe2+ and Zn2+ complexes conserving their structure even in coordinating solvents like dmso at high temperatures. Their solution behavior was investigated using variable temperature (VT) 1H NMR spectroscopy and VT Vis spectroscopy. SCO behavior was found for all Fe2+ complexes in this series centred around and far above room temperature. For the first time we have demonstrated that the thermodynamics as well as kinetics for SCO can be deduced by using VT 1H NMR spectroscopy. An alternative scheme using a linear correction term C1 to model chemical shifts for Fe2+ SCO complexes is presented. The rate constant for the SCO of [Fe(rac-trans-5)]2+ obtained by VT 1H NMR was validated by Laser Flash Photolysis (LFP), with excellent agreement (1/(kHL + kLH) = 33.7/35.8 ns for NMR/LFP). The solvent dependence of the transition temperature T1/2 and the solvatochromism of complex [Fe(rac-trans-5)]2+ were ascribed to hydrogen bond formation of the secondary amine to the solvent. Enantiomerically pure complexes can be prepared starting with R,R- or S,S-1,2-diaminocyclohexane (R,R-trans-4 or S,S-trans-4). The high robustness of the complexes reduces a possible ligand scrambling and allows preparation of quasiracemic crystals of [Zn(R,R-5)][Fe(S,S-5)](ClO4)4·(CH3CN) composed of a 1 : 1 mixture of the Zn and Fe complexes with inverse chirality. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Les transitions de spin provoquent des changements de propriétés physiques des complexes de métaux du bloc d les subissant, notamment de leur structure et propriétés spectroscopiques. Ce mémoire porte sur la spectroscopie Raman de composés du fer(II) et du fer(III), pour lesquels on induit une transition de spin par variation de la température ou de la pression. Trois complexes de fer(II) de type FeN4(NCS)2 avec des comportements de transition de spin différents ont été étudiés : Fe(Phen)2(NCS)2 (Phen : 1,10-Phénanthroline), Fe(Btz)2(NCS)2 (Btz : 2,2’-bi-4,5-dihydrothiazine) et Fe(pyridine)4(NCS)2. Un décalage de l’ordre de 50 cm-1 est observable pour la fréquence d’étirement C-N du ligand thiocyanate des complexes FeN4(NCS)2, lors de la transition de spin induite par variation de la température ou de la pression. Il est possible d’utiliser cette variation de fréquence afin de tracer un profil de transition. Quatre complexes isomères de type FeL222(CN)2 (L222 : 2,13- diméthyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]-octadéca-1(18),2,12,14,16-pentaène) ont également été étudiés. Un taux de décalage de l’ordre d’environ 0,03 cm-1/K est observé pour plusieurs bandes du complexe FeL222(CN)2. La bande à 1415 cm-1 disparaît à plus haute température au profit d’une bande à 1400 cm-1. Pour le complexe de chiralité R,R’, les bandes à 1008 cm-1 et 1140 cm-1 se déplacent vers des fréquences plus élevées à partir de 223 K. Les transitions de spin sont observées dans certains complexes de fer(III). Dans cette famille de composés, le complexe Fe(EtDTC)3 (EtDTC : N,N-diéthyldithiocarbamate) a été étudié . Aucun changement n’a été observé dans l’intensité des bandes d’étirement fer-soufre sur les spectres à température variable. Cependant, la bande Fe-S associée à la forme bas-spin à 530 cm-1 augmente en intensité au profit de la bande associée à la forme haut-spin à 350 cm-1 lors des mesures à haute pression, passant d’un rapport d’amplitude de 50% à pression ambiante à 80% à 21 kbar. Un dédoublement de la bande d’étirement C-N du ligand dithiocarbamate à 1495 cm-1 est également observé à des pressions supérieures à 5 kbar. Une comparaison des changements des fréquences de vibration de tous les complexes est effectuée. / AbstractSpin crossover processes lead to significant changes of molecular structures and spectroscopic properties measured for complexes of d-block transition metals. This thesis focuses on vibrational Raman spectroscopy of iron(II) and iron(III) compounds with spin transitions induced through temperature and pressure variations. Three iron(II) complexes of type FeN4(NCS)2 with different spin transition patterns have been studied: Fe(Phen)2(NCS)2 (Phen : 1,10-Phenanthroline), Fe(Btz)2(NCS)2 (Btz : 2,2’-bi-4,5- dihydrothiazine) and Fe(pyridine)4(NCS)2. A 50 cm-1 shift has been found for the C-N stretching frequency of the thiocyanate ligand in these compounds as a consequence of the spin transition induced by temperature or pressure. These frequency variations have been used to trace different transition profiles. Four different isomers of FeL222(CN)2 (L222 : [2,13-dimethyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]-octadeca-1(18),2,12,14,16- pentaene]) type complexes have also been studied. A variation with temperature of approximately 0,03 cm-1/K has been observed for a few bands for the FeL222(CN)2 complex. A band at 1415 cm-1 decreases in intensity in favour of a band at 1400 cm-1 as temperature rises. The bands at 1008 cm-1 and 1140 cm-1 for the complex of R,R’ configuration shift to higher frequencies around 223 K. Spin transitions have also been investigated in some iron(III) complexes. In this family of compounds, the Fe(EtDTC)3 (EtDTC : N,N-diéthyldithiocarbamate) complex has been studied. No change has been observed in the intensity of the iron-sulphur stretching bands in spectra measured at variable temperature. However, at high pressure the low-spin Fe-S band at 530 cm-1 gains intensity compared to the high spin band at 350 cm-1. A splitting of the C-N stretching band of the dithiocarbamate ligand at 1495 cm-1 is observed at pressures above 5 kbar. A comparison of all changes in vibrational spectra is presented.