EPR spectroscopy of site-directed spin labeled proteins is extremely informative in the studies of protein dynamics; however, it is difficult to interpret the spectra in terms of the conformational dynamics in atomic detail.In the present work we aimed to investigate the site-specific structural dynamics of proteins by using MD simulations upon analyzing and interpreting the EPR data. The major goal of this work is to know how far the computer simulations can meet the experiments. As a first step, MD simulations are performed to identify the location and orientation of the tyrosine radical in the R2 subunit of ribonucleotide reductase. The MD results show that the tyrosine is moving away from the diiron center in its radical state. This data is in agreement with EPR results and suggests reorientation of the tyrosine radical when compared to its neutral state. In further studies, the behavior of a methanethiosulfonate spin label, R1, in various environments of the protein is characterized by using MD simulations. RMSD analysis and angle ß distributions of the nitroxide show that R1 in buried sites in a protein helix is significantly immobile and in surface exposed sites it is highly mobile. Analyses of MD data suggest that internal rotations of x4 and x5 dihedrals of R1 are dominant in the R1 dynamics.Our studies also show that interaction with the surrounding residues show significant influence on the dynamics of R1. MD simulations data of the vinculin tail protein, both in water and in vacuo, are compared to the experimental results for further analysis of 12 different R1 sites in various environments.In a study on the photosynthetic reaction center(RC),MD is used to identify the location of the R1 binding site (H156)and thereby exploring the conformational dynamics in the RC protein upon light activation. The distance between the primary quinone, QA, and H156R1 determined from MD is in reasonable agreement with that measured by EPR.

Purpose - The purpose of this study is to examine how a warehouse of finished goods can be made more effective with warehouse design, warehouse control, new technologies and how the current way of work must be adjusted to the new technologies. In order to achieve the purpose of the study, the writers had two research questions connected to the purpose. Method - A case study has been conducted as research strategy in collaboration with Smurfit Kappa AB. The study began by researching possible theories that could be relevant to the study. This was followed by an empirical study where interviews and observations were carried out. Documents with floor plans have also been studied to understand the current state of the warehouse. The empirical findings have been compiled, discussed, and compared to the theoretical findings. Results - At the time of the study, the warehouse house of finished goods did not have a system for storing goods. They also do not have an ERP-system and therefore the communication possibilities are limited. The company will implement an ERP-system and barcode scanners in the future which makes it possible to improve the efficiency of the warehouse with design, control, layout, zones, scanners, and standardize movement. There is also new finding of wastage that can be controlled. Findings - Even though the case company of this study can achieve improved efficiency in the warehouse by using the management methods and tools presented in this study, the most important part is to provide the employees with the right information. Thereafter the management methods and tools such as zone sectioning, barcode scanners, and standardized create more effectiveness. In addition to previous findings, two new forms of waste that can occur in a warehouse has been identified. Research limitations - Because of the decisions made by the case company of future implementation of barcode scanners, the researcher felt that there were limitations to the possible improvement proposals. If the researchers could have proposed a different tool, the outcome of the work could have looked different. If there were more interviews or several business cases the generalization it would strengthened the case study. / Syfte - Syftet med detta examensarbete var att undersöka hur färdigvarulagret kan effektiviseras med hjälp av lagerutformning, lagerstyrning och ny teknik och hur arbetssättet måste anpassas till den nya tekniken. För att kunna uppnå syftet med studien har författarna två forskningsfrågor som stöd för att uppnå effektivitet. Metod - För att besvara studiens syfte samt frågeställningar har författarna utfört en fallstudie som undersökningsstrategi på Smurfit Kappa AB. Studien började med att undersöka vilka befintliga teorier som kan kopplas till arbetet. Därefter genomfördes observationer och intervjuer på fallföretaget. Författarna fick även ta del av ritningar för att få förståelse av det nuvarande flödet. Empirin har sedan sammanställts, diskuterats och jämförts mot det teoretiska ramverket. Nulägesbeskrivning - Fallföretagets färdigvarulager använder i dagsläget inget system för lagring av artiklar. De har heller inget affärssystem vilket gör att information inte kan kommuniceras ordentligt. Företaget ska införa ett affärssystem och streckkodsläsare. Detta gör att det finns möjligheter att effektivisera färdigvarulagret. Resultat - Företag kan öka sin effektivitet med hjälp av flera metoder, principer och verktyg. Författarna tror dock att det viktigaste är att medarbetarna får tillräckligt med information för vad som ska göras. Därefter kan olika utformningar och styrningar som layout, zonindelning, streckkodsläsare och standardiserade arbetssätt anpassas för att få ett effektivt färdigvarulager. Utöver detta har två nya slöserier som kan förekomma i ett färdigvarulager identifierats. Begränsningar - Då fallföretaget som undersöktes redan bestämt sig för vilket affärssystem och vilket verktyg som skulle användas i lagerverksamheten, i detta fall streckkodsläsare, upplevde författarna att det fanns begränsningar vid framtagning av förslag på förbättringsåtgärder. Om verktyg inte redan bestämts hade andra lösningar kunnat presenteras. Om studien hade fler intervjuer eller jämförts med fler fallföretag hade generaliseringen ökat.

Ce mémoire vise à montrer l’intérêt de nanoparticules (NPs) de TiO2 comme plateforme pour immobiliser dans un environnement proche des complexes de coordination pouvant interagir par transfert d’électron photoinduit. Nous nous sommes intéressés à l’étude de nanomatériaux hybrides associant le complexe [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine) comme photosensibilisateur aux complexes [Cr(ttpy)2]3+ ou [Mn(ttpy)(CO)3Br] (ttpy = 4'-(p-tolyl)-2,2':6',2''-terpyridine) comme accepteurs d'électrons. Pour immobiliser les différents complexes à la surface du TiO2, une fonction acide phosphonique a été introduite sur une des bipyridines du centre [Ru(bpy)3]2+ et sur la terpyridine des complexes [Cr(ttpy)2]3+. L’étude des processus de transferts de charges photo-induits sous irradiation en lumière visible sur le colloïde TiO2/RuII montre que l'état à charges séparées (e-)TiO2/ RuIII possède une longue durée de vie, ce qui rend possible l'utilisation des charges dans des réactions successives d’oxydation ou de réduction. Notamment l’irradiation du colloïde TiO2/RuII en présence de [Cr(ttpy)2]3+ et de triéthanolamine (TEOA) comme donneur d'électron sacrificiel permet la réduction à deux électrons du [Cr(ttpy)2]3+. Par la suite, le complexe [Cr(ttpy)2]3+ est immobilisé sur les NPs de TiO2/RuII pour former un assemblage RuII/TiO2/CrIII au sein duquel les processus de transfert d'électrons photo-induits sont étudiés. De manière à proposer un système pour la réduction photocatalytique du CO2, le complexe [Mn(ttpy)(CO)3Br] a été co-immobilisé avec le [Ru(bpy)3]2+ suivant une approche de chimie sur surface pour former le colloïde RuII/TiO2/MnI. Ce système présente une excellente sélectivité vis-à-vis du HCOOH comme seul produit de la photoréduction du CO2 en présence de 1-benzyl-1,4-dihydronicotinamide (BNAH) comme donneur d'électron sacrificiel. Un système hybride associant le [Ru(bpy)3]2+ portant des fonctions pyrroles et immobilisé sur TiO2 a également été synthétisé et étudié. Sous irradiation lumineuse, le transfert de charges (e-)TiO2/[Ru-pyr]3+ permet d’induire la polymérisation du pyrrole. Le nanocomposite TiO2/poly(Ru-pyr) obtenu et déposé sur une électrode génère, en présence de TEOA, un photocourant anodique stable de plus de 10 μA.cm-2. L’ensemble des résultats montre que les NPs de TiO2 peuvent être un moyen d’assembler des complexes dans un environnement proche en limitant les interactions à l’état fondamental, mais permettant des transferts d’électrons photoinduits entre eux. Suivant les potentiels redox des différents composants, les transferts d’électron ont lieu soit via la nanoparticule soit en surface de celle-ci. / This thesis aims to investigate the possibility of using TiO2 nanoparticles (NPs) as a platform to immobilize proximal coordination complexes that can interact with each other by photoinduced electron transfer. We have studied hybrid nanomaterials combining [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine) as a photosensitizer and [Cr(ttpy)2]3+ or [Mn(ttpy)(CO)3Br (ttpy = 4'-(p-tolyl)-2,2':6',2''-terpyridine) as electron acceptors. To immobilize the various complexes on the surface of TiO2, a phosphonic acid functional group was introduced on one of the bipyridines of the [Ru(bpy)3]2+ center and on the terpyridines of the [Cr(ttpy)2]3+ complex. Under visible light, the TiO2/RuII colloid undergoes a photo-induced charge transfer process leading to a long-lived charge separation state (e )TiO2/RuIII, which makes it possible to be engaged in successive oxidation or reduction reactions. In particular, the visible irradiation of the TiO2/RuII colloid in the presence of [Cr(ttpy)2]3+ and triethanolamine (TEOA) as a sacrificial electron donor allows the two-electron reduction of [Cr(ttpy)2]3+. Subsequently, the [Cr(ttpy)2]3+ complex has been immobilized on the TiO2/RuII NPs to form a RuII/TiO2/CrIII assembly in which the photoinduced electron transfer processes were investigated. In order to propose a system for the photocatalytic reduction of CO2, the [Mn(ttpy)(CO)3Br] and [Ru(bpy)3]2+ complexes were co-immobilized on TiO2 NPs following a chemistry on surface approach to form a RuII/TiO2/MnI triad. Under irradiation at 470 nm, this system exhibits excellent selectivity towards HCOOH as the only product of CO2 photoreduction in DMF/TEOA solvent mixture, in the presence of 1-benzyl-1,4-dihydronicotinamide (BNAH) as a sacrificial electron donor. Another hybrid system linking a [Ru(bpy)3]2+ unit to two pyrrole functions and being immobilized on TiO2 has also been synthesized and studied. Under visible light, the transient (e-)TiO2/[Ru-pyr]3+ species induce the polymerization of pyrrole to form a TiO2/poly(Ru-pyr) nanocomposite. The nanocomposite deposited on an electrode generates, in the presence of TEOA, a stable anodic photocurrent of more than 10 μA.cm-2. All the results show that TiO2 NPs can be used to associate different complexes in a close environment by limiting the interactions in the ground state but allow photoinduced electron transfer processes between them. Depending on the redox potentials of the different components, the electron transfer takes place either through the semiconducting NPs or on the surface.

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