[ES] La presente tesis doctoral ha centrado la atención en la síntesis de nuevos materiales MOFs obtenidos por intercambio post-sintético de MOFs descritos anteriormente o por heterounión de MOFs estables que tienen estructura UiO66. Estos materiales se han aplicado como fotocatalizadores para la prometedora reacción de división completa del agua que pretende obtener H2 y O2 en forma estequiométrica a partir de agua en ausencia de agentes sacrificantes o nanopartículas metálicas. El nuevo material UiO66 (Zr/Ce/Ti) mostró resultados sorprendentes para la reacción general de división del agua en ambas condiciones de luz UV-Visible e irradiación solar. También se obtuvieron resultados interesantes en el caso del nucleo-corteza UiO66(Zr)-NH225@UiO66(Ce) que, en presencia de agua, cuando se irradió con luz ultravioleta y con luz solar, permitió obtener 550 𝝁 mol*g- 1 de H2 y 350 𝝁 mol*g-1 de H2 en 24 h respectivamente, en las mismas condiciones de trabajo definidas para UiO66(Zr/Ce/Ti). En este trabajo de tesis se presentó por primera vez la posibilidad de reducir 4-NP a través de una metodología tándem que involucra primero la producción de H2 a partir de agua en presencia de metanol, como agente de sacrificio, y UiO66(Zr)-NH2, como fotocatalizador, y la posterior reducción de 4-NP a 4-AP. Por otro lado, se ha demostrado que los materiales defectuosos con estructura de UiO66 pueden reducir selectivamente los dobles enlaces polarizados X=Y en presencia de gas H2. / [CA] La present tesi doctoral ha centrat l'atenció en la síntesi de nous materials MOFs obtinguts per intercanvi post-sintètic de MOFs descrits anteriorment o per heterounió de MOFs estables que tenen estructura UiO66. Estos materials s'han aplicat com fotocatalitzadors per a la prometedora reacció de divisió completa de l'aigua que pretén obtindre H2 i O2 en forma estequiomètrica a partir d'aigua en absència d'agents sacrificants o nanopartícules metàl·liques. El nou material UiO66 (Zr/Ce/Ti) va mostrar resultats sorprenents per a la reacció general de divisió de l'aigua en ambdós condicions de llum UV-Visible i irradiació solar. També es van obtindre resultats interessants en el cas del core-shell UiO66 (Zr) - NH225@UiO66 (Ce) que, en presència d'aigua, quan es va irradiar amb llum ultravioleta i amb llum solar, va permetre obtindre 550 𝝁 mol*g-1 de H2 i 350 𝝁 mol*g-1 de H2 en 24 h respectivament, en les mateixes condicions de treball definides per a UiO66 (Zr/Ce/Ti). En este treball de tesi es va presentar per primera vegada la possibilitat de reduir 4-nitrofenol a través d'una metodologia tàndem que involucra primer la producció de H2 a partir d'aigua en presència de metanol, com a agent de sacrifici, i UiO66 (Zr) -NH2, com fotocatalizador, i la posterior reducció de 4-NP a 4-AP. D'altra banda, s'ha demostrat que els materials defectuosos amb estructura d'UiO66 poden reduir selectivament els dobles enllaços polaritzats X=Y en presència de gas H2. / [EN] The present doctoral thesis has focused the attention on the synthesis of new MOFs materials obtained either by post-synthetic interchange of previously described MOFs or by heterojunction of stable MOFs having UiO66 structure. These materials have been applied as photocatalysts for the promising Overall Water Splitting reaction which claims to obtain H2 and O2 stoichiometrically starting from water in the absence of sacrificial agents or deposited metals nanoparticles. The new material UiO66 (Zr/Ce/Ti) showed surprising results in both UV- Visible light and sunlight irradiation conditions. Interesting results were also obtained in the case of the core-shell named UiO66(Zr)-NH225@UiO66(Ce) which, in the presence of water, when irradiated with both ultraviolet and solar light, allowed to obtain 550 𝝁 mol*g-1 of H2 and 350 𝝁 mol*g-1 of H2 in 24 h respectively, in the same working conditions defined for UiO66 (Zr/Ce/Ti). In this thesis was presented, for the first time, the possibility of reducing 4NP through a tandem methodology which, first, involves the production of H2 from water in the presence of methanol as a sacrificial agent and UiO66(Zr)-NH2 as a photo-catalyst, and subsequent the 4 NP reduction to 4 AP. On the other hand, it has been shown that defective materials with UiO66 structure can selectively reduce polarized X=Y double bonds in the presence of H2 gas. / Melillo, A. (2022). Metal-Organic Hybrid Materials with Catalytic and Photocatalytic Applications [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182744 / TESIS

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Comme nous le savons, les applications sont déterminées par des propriétés, qui sont essentiellement déterminées par la structure. L’interaction entre la forme (structure moléculaire) et la fonction (propriétés physiques) peut être exploitée par le ligand, l’ion métallique, l'approche métallacrown et ainsi de suite. Les travaux portent sur la synthèse et l’étude du comportement magnétique de complexes mononucléaires cobalt(II) de géométrie bipyramide trigonale et sur l’étude de complexes mononucléaires de lanthanides possédant une structure de type métallacrown.Pour les complexes de cobalt(II), l’objectif a été de modifier l’anisotropie magnétique en modifiant la nature du ligand organique tétradenté et du ligand terminal en gardant, autant que faire se peut, la géométrie et même la symétrie des complexes. Presque tous ces complexes se comportent comme des molécules-aimants avec une barrière énergétique à l’inversion de l’aimantation qui peut être liée à leur anisotropie magnétique et donc à la nature des ligands. Et les complexes métallacrown à base de lanthanides étant hautement symétriques, permet de les utiliser comme modèles pour effectuer une corrélation entre la nature de l’ion lanthanide et leurs propriétés d’aimants.La thèse est composée de 6 chapitres. Le chapitre 1 présente l’état de l’art du magnétisme, des molécules-aimants (SMMs et SIMs), et quelques exemples importants. Le chapitre 2 se concentre sur une famille de complexes de géométriebipyramide trigonale de formule générale [Co(Me6tren)X]Y avec le ligand axial (X) et le contre-ion (Y) induisant le comportement SMM.Dans cette série de composés, j’ai étudié l’influence du ligand axial X sur la nature et l’amplitude de l’anisotropie magnétique. J’ai montré que la série des halogénures, l’anisotropie la plus forte est obtenue pour le ligand axial fluorure (F–). J’ai aussi étudié l’effet du cation Y qui influence l’interaction entre les molécules qui affectent le comportement d’aimant moléculaire. Au chapitre 3, on étudie l’influence du changement du ligand tétradenté. Le remplacement des trois atomes d’azote qui se trouvent en position équatoriale dans la sphère de coordination de cobalt(II) par des atomes de soufre induit une augmentation des distances Co–L dans le plan équatorial qui conduit à une plus forte anisotropie. Les calculs théoriques effectués sur ces complexes permettent de rationaliser les résultats expérimentaux et surtout de prévoir les propriétés de nouveaux complexes. Les chapitres 4 et 5 concernent deux séries de SMM 12-MC-4 basées sur LnGa4 (Ln = TbIII, DyIII, HoIII, ErIII, YbIII) avec les ligands basés sur l’acide salicylhydroxamique (H3shi) et l’acide 3-hydroxy-2-naphtohydroxamique (H3nha). J’ai préparé plusieurs complexes et étudié leurs propriétés magnétiques. Les calculs théoriques permettent de rationaliser la différence entre les propriétés des magnétiques dues aux différents ions lanthanide. Enfin, une conclusion générale avec des perspectives sont récapitulées au chapitre 6. / As we know, the applications are determined by properties, which are essentially determined by structure. The interplay between form (molecular structure) and function (physical properties) can be exploited engineering by the ligand, the metal ion, the metallacrown approach and so on. The work focuses on the synthesis and the study of the magnetic behavior of mononuclear cobalt(II) complexes with trigonal geometry and on the study of mononuclear lanthanide complexes that possess a metallacrown structure.For the cobalt(II) complexes, the aim was to tune the magnetic anisotropy by changing the nature of the tetradentate organic ligand and the terminal ligand. Almost all these complexes behave as Single Molecule Magnets with an energy barrier to the reversal of the magnetization that can be linked to their magnetic anisotropy and thus to the nature of the organic ligands. The lanthanide containing metallacrown complexes are highly symmetric, which allows performing a correlation between the nature of the lanthanide ion and their Single Molecule Magnet properties.The dissertation will be composed of 6 chapters. Chapter 1 introduces the background of the magnetism, Single Molecule Magnets, Single Ion Magnets, and some important SIMs. Chapter 2 focuses on a family of trigonal bipyramidal complexes [Co(Me6tren)X]Y. We show that the axial ligand affects the SMM behavior allowing us to prepare a complex with a magnetic bistability at T = 2 K. In Chapter 3, we examine the effect of changing the coordinated atoms (sulfur instead of nitrogen) in the equatorial coordination sphere of cobalt(II). We demonstrate that this slight change improves the SMM behavior. Chapter 4 and 5, which concern two series of 12-MC-4 SMMs based on LnGa4 (Ln = TbIII, DyIII, HoIII, ErIII, YbIII) with the ligands salicylhydroxamic acid (H3shi) and 3-hydroxy-2-naphthohydroxamic acid (H3nha), respectively, where we correlate the nature of the lanthanide ion to its magnetic behavior using ab initio calculations. At last, the understanding gained from this dissertation research, along with future research directions will be recapitulated in Chapter 6.

The celebrated Schrödinger equation is the key to understanding the dynamics of quantum mechanical particles and comes in a variety of forms. Its numerical solution poses numerous challenges, some of which are addressed in this work. Arguably the most important problem in quantum mechanics is the so-called harmonic oscillator due to its good approximation properties for trapping potentials. In Chapter 2, an algebraic correspondence-technique is introduced and applied to construct efficient splitting algorithms, based solely on fast Fourier transforms, which solve quadratic potentials in any number of dimensions exactly - including the important case of rotating particles and non-autonomous trappings after averaging by Magnus expansions. The results are shown to transfer smoothly to the Gross-Pitaevskii equation in Chapter 3. Additionally, the notion of modified nonlinear potentials is introduced and it is shown how to efficiently compute them using Fourier transforms. It is shown how to apply complex coefficient splittings to this nonlinear equation and numerical results corroborate the findings. In the semiclassical limit, the evolution operator becomes highly oscillatory and standard splitting methods suffer from exponentially increasing complexity when raising the order of the method. Algorithms with only quadratic order-dependence of the computational cost are found using the Zassenhaus algorithm. In contrast to classical splittings, special commutators are allowed to appear in the exponents. By construction, they are rapidly decreasing in size with the semiclassical parameter and can be exponentiated using only a few Lanczos iterations. For completeness, an alternative technique based on Hagedorn wavepackets is revisited and interpreted in the light of Magnus expansions and minor improvements are suggested. In the presence of explicit time-dependencies in the semiclassical Hamiltonian, the Zassenhaus algorithm requires a special initiation step. Distinguishing the case of smooth and fast frequencies, it is shown how to adapt the mechanism to obtain an efficiently computable decomposition of an effective Hamiltonian that has been obtained after Magnus expansion, without having to resolve the oscillations by taking a prohibitively small time-step. Chapter 5 considers the Schrödinger eigenvalue problem which can be formulated as an initial value problem after a Wick-rotating the Schrödinger equation to imaginary time. The elliptic nature of the evolution operator restricts standard splittings to low order, ¿ < 3, because of the unavoidable appearance of negative fractional timesteps that correspond to the ill-posed integration backwards in time. The inclusion of modified potentials lifts the order barrier up to ¿ < 5. Both restrictions can be circumvented using complex fractional time-steps with positive real part and sixthorder methods optimized for near-integrable Hamiltonians are presented. Conclusions and pointers to further research are detailed in Chapter 6, with a special focus on optimal quantum control. / Bader, PK. (2014). Geometric Integrators for Schrödinger Equations [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/38716 / TESIS / Premios Extraordinarios de tesis doctorales

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第21216号 / 情博第669号 / 新制||情||115(附属図書館) / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 守倉 正博, 教授 大木 英司, 教授 梅野 健 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

N. Riethof - Burnout syndrome in Health Care Professionals ABSTRACT Burnout syndrome is a state of total exhaustion related to work condi- tions and prolonged stress. While initial phases of burnout resemble stress symptoms, final phases of burnout are characterized by feelings of hopelessness, loss of meaning and desperation that have similar qual- ities as depression as well as existential vacuum described by Frankl in his logotherapy. In addition, the burnout syndrome involves stages in which people detach from their emotions and feelings as a defense mechanism against stress and have decreased ability to experience their own feelings and emotional states. Burnout usually begins with feelings of enthusiasm and idealized visualizations and it is in contrast with sub- sequent disillusionment, disappointment experienced later. After decades of burnout research, there is still a need for better def- inition of this condition including more precise diagnostic criteria and internationally recognized measurement tools, especially within health care system where the risks of unrecognized and untreated burnout are high. This study is focused on examination of potential causes of burn- out and relationships of burnout symptoms with certain personality traits, defense mechanisms and coping reactions including...

Since a large part of the hydropower structures in Sweden was built in the 1950s and 1960s, many of them are slowly but surely exhibiting deterioration. The hydropower companies are facing big challenges and are consequently investing in effective repairing methods since a hydropower structure failure could pose serious consequences and dangers to people, the environment, and the community. Many structures within hydropower are made of concrete and the demands on the new supplementing concrete are high. Concrete with the potential to meet these high demands is the pre-placed aggregate concrete, which has shown promising results regarding its mechanical properties in previous studies. For this reason, this type of concrete is of interest to investigate. The focus has not been on optimizing the pre-placed aggregate concrete for full-scale productions. Instead, the main objectives of this master thesis were to study and analyze the mechanical properties of this type of concrete, such as shrinkage, compressive strength, splitting tensile strength, freeze-thaw resistance and moreover investigate parameters of importance in the mix design to obtain a homogenous and easy flowing grout that successfully could fill the voids between the coarse aggregates. The investigations were carried out by laboratory experiments in the research and laboratory facilities of Vattenfall in Älvkarleby. The mix design of the grout was developed using the methods and requirements stated in the American Society for Testing and Materials, ASTM standards, and The Swedish Institute for Standards, SiS. A total of 15 grout-mixes were made. However, only the last five were used to cast specimens as the air content was insufficient in the first ten. The results indicated that it is necessary to replace the air-entraining admixture with microspheres in order for the pre-placed aggregate concrete to meet the requirements in exposure class XF3 and XC4. The scaling of the pre-placed aggregate concrete was less than 0.1 kg/m2 at 56 cycles, and thus, the freeze-thaw resistance was classed as very good. Moreover, the use of slag considerably reduced the bleeding of the grout and also improved the casting results. However, on the other hand, it increased the shrinkage of the pre-placed aggregate concrete. An efficiency factor of 0.6 proved to be too low since the compressive strength of the specimen with slag was approximately 50 % higher than the ones without. Furthermore, the shrinkage of the pre-placed aggregate concrete was after 63 days found to be lower than that of the conventional concrete. Also, the compressive strength of the pre-placed aggregate concrete without slag proved to be approximately 15 % lower than that of conventional concrete. Additionally, vibration during casting was found to increase the compressive strength of the pre-placed aggregate concrete and also improved the casting results. Low bleeding, combined with a high discharge time of approximately 45 seconds for 1.7 liters of grout, generated the best casting results. The results from the investigations have shown that this type of concrete has great potential. However, actions and further investigations should be made to see whether changing the fine aggregate size to a smaller one improves the ability of the grout to penetrate the voids between the coarse aggregates. Moreover, pump injection of the grout should be tested instead of pouring it over the coarse aggregates to see whether it improves the casting results and the mechanical properties. / Då en stor del av vattenkraftsdammarna i Sverige byggdes på 1950 och 1960-talet börjar många av dessa sakta men säkert brytas ner. Vattenkraftföretagen står inför stora utmaningar och investerar följaktligen i effektiva reparationsmetoder då dammbrott skulle kunna få allvarliga konsekvenser för människor, den omgivande miljön och för samhället. Flertalet konstruktioner inom vattenkraften är gjorda av betong och kraven på den nya kompletterande betongen är höga. En betong med potentialen att möta och uppfylla dessa höga krav är injekteringsbetongen som i tidigare studier uppvisat lovande resultat beträffande dess mekaniska egenskaper. Med anledning av detta är injekteringsbetongen av intresse att undersöka. Fokus har inte varit på att optimera injekteringsbetongen i syfte att genomföra fullskaliga försök. Istället har huvudsyftet med detta examensarbete varit att studera och analysera injekteringsbetongens mekaniska egenskaper såsom krympning, tryckhållfasthet, spräckhållfasthet, frostbeständighet samt undersöka viktiga parametrar i skapandet av ett homogent och lättflytande cementbruk som med god framgång kunde fylla ut hålrummen mellan grova ballasten. Undersökningarna utfördes genom laboratorieförsök på Vattenfalls betonglaboratorium i Älvkarleby. Vidare har skapandet och utvecklandet av bruket utförts i enlighet med metoder och krav angivna i American Society for Testing and Materials, ASTM standards, samt i Svenska institutet för Standarder, SiS. Totalt gjordes 15 bruksblandningar, dock användes enbart de sista fem till gjutning av provkroppar då lufthalten visade sig vara för låg i dem första tio. Resultaten indikerade på att det är nödvändigt att ersätta luftporbildare med mikrosfärer för att erhålla en lufthalt som uppfyller kraven för betong i exponeringsklass XF3 samt XC4. Injekteringbetongens avflagning efter 56 dygn var mindre än 0.1 kg/m2 och frostbeständigheten kunde därmed klassas som mycket god. Användningen av slagg minskade cementbrukets vattenseparation avsevärt och bidrog även till förbättrade gjutresultat. Dock bidrog det å andra sidan till en ökad krympning hos injekteringsbetongen. En effektivitetsfaktor på 0.6 visade sig vara för låg då injekteringsbetongen med slagg hade en cirka 50 % högre tryckhållfasthet än dem utan. Dessutom visade sig injekteringsbetongens krympning vara mindre än den konventionella betongens efter 63 dagar. Tryckhållfastheten hos injekteringsbetongen utan slagg uppvisade även en cirka 15 % lägre tryckhållfasthet än den konventionella betongens. Vibrering under gjutning visade sig höja tryckhållfastheten hos injekteringsbetongen samt förbättra gjutresultaten. En låg vattenseparation i kombination med en flödestid på cirka 45 sekunder för 1.7 liter bruk visade sig ge bästa gjutresultaten. Resultaten från laboratorieförsöken har visat på att injekteringsbetongen besitter stor potential. Dock bör ytterligare undersökningar genomföras för att bedöma huruvida en mindre ballastfraktion för sanden påverkar brukets förmåga att penetrera den grova ballasten. Vidare bör bruket pumpas in istället för att hällas över den grova ballasten, detta för att se huruvida gjutresultaten samt de mekaniska egenskaperna hos injekteringsbetongen skulle förbättras.

This thesis addresses electron spin phenomena in semi-conductor quantum dots/anti-dots from a computational perspective. In the first paper (paper I) we have studied spin-dependent transport through open quantum dots, i.e., dots strongly coupled to their leads, within the Hubbard model. Results in this model were found consistent with experimental data and suggest that spin-degeneracy is lifted inside the dot – even at zero magnetic field. Similar systems were also studied with electron-electron effects incorporated via Density Functional Theory (DFT) in paper III. Within DFT we found a significant spin-polarisation in the dot at low electron densities. As the electron density increases the spin polarisation in the dot gradually diminishes. These findings are consistent with available experimental observations. Notably, the polarisation is qualitatively different from the one found in the Hubbard model – this indicates that the simplified approach to electronelectron interaction in the Hubbard model might not always be reliable. In paper II we propose a spin-filter device based on resonant backscattering of edge states against a quantum anti-dot embedded in a quantum wire. A magnetic field is applied and the spin up/spin down states are separated through Zeeman splitting. Their respective resonant states may be tuned so that the device can be used to filter either spin in a controlled way. / <p>Report code: LIU-Tek-Lic 2005:65</p>

We derive the regularised evolution equations for the parton distribution functions that include tensorgluons.

Multi-User Multi-Input Multi-Output (MU-MIMO) systems are considered to be the sustainable technologies of the current and future of the upcoming wireless and mobile networks generations. The perspectives of these technologies under several scenarios is the focus of the present thesis. The initial system model covers the MU-MIMO, especially in the massive form that is considered to be the promising ideas and pillars of the 5G network. It is observed that the optimal number of users should be served in the time-frequency resource even though the maximum limitation of the MU-MIMO is governed by the total receiving antennas (K) is less than or equal to the base station antennas (M). The system capacity of the massive MIMO (mMIMO) under perfect channel state information (CSI) of uncorrelated channel is investigated and studied. Two types of precoders were applied, one is directly based on channel inversion, and the other uses the Eigen decomposition that is derived subject to the signal to a leakage maximization problem. The two precoders show a degree of equivalency under certain assumptions for the number of antennas at the user end. The convex optimization of multi-antenna networks to achieve the design model of optimum beamformer (BF) based on the uniform linear array (ULA) is studied. The ULA is selected for its simplicity to analyse many scenarios and its importance to match the future network applied millimetre wave (mmWave) spectrum. The maximum beams generated by the ULA are explored in terms of several physical system parameters. The duality between the MU-MIMO and ULA and how they are related based on beamformer operation are detailed and discussed. Finally, two approaches for overloaded systems are presented when the availability of massive array that is not guaranteed due to physical restrictions since the existence of a large number of devices will result in breaking the dimension rule (i.e., K ≤ M). As a solution, a low complexity users selection algorithm is proposed. The channel considered is uncorrelated with full and perfect knowledge at the BS. In particular, these two channel conditions may not be available in all scenarios. The CSI may be imperfect, and even the instantaneous form does not exist. A hybrid precoder between the mixed CSI (includes imperfect and statistical) and rate splitting approach is proposed to deal with an overloaded system under a low number of BS antennas. / Ministry of Higher Education and Scientific Research of Iraq