Being able to keep track of ones assets is a very useful thing, from avoiding losing ones keys or phone to being able to find the needed equipment in a busy hospital or on a construction site. The area of localization is actively evolving to find the best ways to accurately track objects and devices in an energy efficient manner, at any range, and in any type of environment. This thesis focuses on the last aspect of maintaining accurate localization regardless of environment. For radio frequency based systems, challenging environments containing many obstacles, e.g., indoor or urban areas, have a detrimental effect on the measurements used for positioning, making them deceptive. In this work, a method for correcting range measurements is proposed for a narrowband sub-GHz radio frequency based localization system using Received Signal Strength Indicator (RSSI) and Time-of-Flight (ToF) measurements for positioning. Three different machine learning models were implemented: a linear regressor, a least squares support vector machine regressor and a gaussian process regressor. They were compared in their ability to predict the true range between devices based on raw range measurements. Achieved was a 69.96 % increase in accuracy compared to uncorrected ToF estimates and a 88.74 % increase in accuracy compared to RSSI estimates. When the corrected range estimates were used for positioning with a trilateration algorithm using least squares estimation, a 67.84 % increase in accuracy was attained compared to positioning with uncorrected range estimates. This shows that this is an effective method of improving range estimates to facilitate more accurate positioning. / Att kunna hålla reda på var ens tillgångar befinner sig kan vara mycket användbart, från att undvika att ens nycklar eller telefon tappas bort till att kunna hitta utrustningen man behöver i ett myllrande sjukhus eller på en byggarbetsplats. Området av lokalisering utvecklas aktivt för att hitta de bästa metoderna och teknologierna för att med precision kunna spåra fysiska objekt på ett energieffektivt sätt, på vilken räckvidd som helst, och i vilken miljö som helst. Detta arbete fokuserar på den sista aspekten av att uppnå precis positionering oavsett miljö. För radiofrekvensbaserade system har utmanande miljöer med många fysiska hinder som till exempel inomhus och stadsområden en negativ effekt på de mätningar som används för positionering, vilket gör dem vilseledande. I detta arbete föreslås en metod för att korrigera avståndsmätningar i ett narrowband sub-GHz radiofrekvensbaserat lokaliseringssystem som använder Received Signal Strength Indicator (RSSI)- och Time-of-Flight (ToF)-mätningar för positionering. Tre olika maskininlärningsmodeller har implementerats: en linear regressor, en least squares support vector machine regressor och en gaussian process regressor. Dessa jämfördes i sin förmåga att förutspå det sanna avståndet mellan enheter baserat på råa avståndsmätningar. De korrigerade avståndsmätningarna uppnådde 69.96 % högre nogrannhet jämfört med okorrigerade ToF-uppskattningar och 88.74 % högre nogrannhet jämfört med RSSI-uppskattningar. Avståndsuppskattningarna användes för positionering med trilateration och minsta kvadratmetoden. De korrigerade uppskattningarna gav 67.84 % mer precis positionering jämfört med de okorrigerde uppskattningarna. Detta visar att detta är en effektiv metod förbättra avståndsuppskattningarna för att i sin tur bidra till mer exakt positionering.

Zwischen 10 und 1000 s nach dem Urknall bildeten sich während der Big Bang Nukleosynthese (BBN) die ersten leichten Elemente aus Protonen und Neutronen. Die primordialen Häufigkeiten dieser Elemente hingen von denWirkungsquerschnitten der beteiligten Kernreaktionen ab. Vergleiche zwischen den Ergebnissen nuklearer Netzwerkrechnungen mit astronomischen Beobachtungen bieten eine einzigartige Möglichkeit, etwas über das Universum zu dieser Zeit zu erfahren. Da es für die p(n,g)d-Reaktion, die eine Schlüsselreaktion der BBN ist, kaum Messungen im relevanten Energiebereich gibt, beruht deren Reaktionsrate in Netzwerkrechnungen auf theoretischen Berechnungen. Darin fließen auch experimentelle Daten der Nukleon-Nukleon-Streuung, des Einfangquerschnitts für thermische Neutronen sowie (nach Anwendung des Prinzips des detaillierten Gleichgewichts) der d(g,n)p-Reaktion mit ein. Diese Reaktion, die Photodissoziation des Deuterons, ist bei BBN-Energien (Tcm = 20–200 keV) ebenfalls kaum vermessen. Die großen experimentelle Unsicherheiten machen Vergleiche mit den präzisen theoretischen Berechnungen schwierig. In den letzten Jahren wurde die d(g,n)p-Reaktion und insbesondere der M1-Anteil des Wirkungsquerschnitts mit quasi-monoenergetischen g-Strahlen aus Laser-Compton-Streuung oder durch Elektrodesintegration untersucht. Üblicherweise verwendete man für Messungen des d(g,n)p-Wirkungsquerschnitts entweder die auf wenige diskrete Energien beschränkte Strahlung des g-Zerfalls oder Bremsstrahlung, für die aber eine genaue Photonenflussbestimmung sowie der Nachweis von einem der Reaktionsprodukte und dessen Energie nötig ist. Da diese Energie im Bereich der BBN relativ gering ist, gab es bisher noch keine absoluten Messung des d(g,n)p-Wirkungsquerschnitts bei Tcm < 5 MeV mit Bremsstrahlung. Das Ziel dieser Dissertation ist eine solche Messung mit einer Unsicherheit von 5 % im für die BBN relevanten Energiebereich und darüber hinaus bis Tcm ~ 2,5 MeV unter Verwendung gepulster Bremsstrahlung an der Strahlungsquelle ELBE. Dieser supraleitende Elektronenbeschleuniger befindet sich am Helmholtz-Zentrum Dresden-Rossendorf und stellte einen Elektronenstrahl hoher Intensität bereit. Die kinetische Elektronenenergie von 5 MeV wurde mit einem Browne-Buechner-Spektrometer präzise gemessen. Die Energieverteilung der in einer Niob-Folie erzeugten Bremsstrahlungsphotonen wurde berechnet. Die Photonenflussbestimmung nutzte die Kernresonanzstreuung an 27Al, das sich mit deuteriertem Polyethylen in einem mehrschichtigen Target befand. Die 27Al-Abregungen wurden mit abgeschirmten, hochreinen Germanium-Detektoren nachgewiesen, deren Effektivität mit GEANT4 simuliert und durch Quellmessungen normiert wurde. Die Messung der Energie der Neutronen aus der d(g,n)p-Reaktion erfolgte mittels deren Flugzeit in Plastikszintillatoren, die an zwei Seiten von Photoelektronenvervielfachern mit hoher Verstärkung ausgelesen wurden. Die Nachweiseffektivität dieser Detektoren wurde in einem eigenen Experiment in den Referenz-Neutronenfeldern der PTB Braunschweig kalibriert. Die Nachweisschwelle lag bei etwa 10 keV kinetischer Neutronenenergie.Wegen der guten Zeitauflösung der Neutronendetektoren und des ELBE-Beschleunigers genügte eine Flugstrecke von nur 1 m. Die Energieauflösung betrug im d(g,n)p-Experiment 1–2 %. Leider gingen viele Neutronen bereits durch Streuung in dem großen Target verloren oder sie wurden erst durch Teile des kompakten Experimentaufbaus in die Detektoren gestreut. Beide Effekte wurden mit Hilfe von FLUKA simuliert um einen Korrekturfaktor zu bestimmen, der aber bei niedrigen Energien relativ groß war. Der d(g,n)p-Wirkungsquerschnitts wurde daher nur im Bereich 0.7 MeV < Tcm < 2.5 MeV bestimmt. Die Ergebnisse stimmen mit anderen Messungen, Daten-Evaluierungen sowie theoretischen Rechnungen überein. Die Gesamtunsicherheit beträgt circa 6.5 % und kommt zu fast gleichen Teilen von den statistischen und systematischen Unsicherheiten. Die statistische Unsicherheit könnte durch eine längere FLUKA Simulation noch von 3–5 % auf 1 % verringert werden. Die systematische Unsicherheit von 4.5 % ist vorrangig auf die Photonenflussbestimmung, die Neutronen-Nachweiseffektivität und die Target-Zusammensetzung zurückzuführen.

This thesis presents HELIOS, an in-house laboratory for time-resolved pump-probe spectroscopy with extreme-ultraviolet (XUV) probe radiation. A wide span of pump wavelengths can be generated using commercial laser equipment while XUV probe radiation is generated via a high harmonic generation process in a noble gas delivering probe photons with energies between 20 eV and 72 eV. The XUV beam path features a time-preserving monochromator and was constructed and built in-house. HELIOS features an overall time resolution of about 50 fs when using 800 nm pump and 41 eV probe photons. An energy resolution of 110 meV at 41 eV photon energy can be achieved. HELIOS features two beamlines. One µ-focus beamline with an XUV focal size of about 20 µm can be used with experiments that require such a small XUV focal size as well as with different end stations. The other beamline features a semi-permanently mounted end station for angle-resolved photoelectron spectroscopy under ultra-high vacuum conditions. Experiments demonstrating the usability of HELIOS and the two beamlines are presented. A pump-probe measurement on graphene demonstrates the capability of determining a large part of the k-space in only one measurement due to the use of an ARTOF angle-resolved time-of-flight electron spectrometer. A non-angle-resolved pump-probe measurement on the conducting polymer PCPDTBT demonstrates the high signal-to-noise ratio achievable at this beamline in non-angle-resolved photoelectron-spectroscopy pump-probe measurements. The usability of the µ-focus beamline is demonstrated with time-resolved measurements on magnetic samples employing an in-house-designed spectrometer. These experiments allow the retrieval of element-specific information on the magnetization within a sample employing the transversal magneto-optical Kerr effect (T-MOKE). Additionally, a Fourier transform spectrometer for the XUV is presented, the concept was tested at a synchrotron and it was used to determine the longitudinal coherence of the XUV radiation at HELIOS.

In this dissertation, different approaches have been employed to address the quest of understanding the formation and growth mechanisms of carbon-containing molecular ions with relevance to astrochemistry. Ion mobility mass spectrometry and DFT computations were used to investigate how a second nitrogen in the pyrimidine ring will affect the formation of a covalent bond between the benzene radical cation and the neutral pyrimidine molecule, after it was shown that a stable covalent adduct can be formed between benzene radical cation and the neutral pyridine. Evidence for the formation of a more stable covalent adduct between the benzene radical cation and the pyrimidine is reported here. The effect of substituents on substituted-benzene cations on their solvation by an HCN solvent was also investigated using ion mobility mass spectrometry and DFT computations were also investigated. We looked at the effect of the presence of electron-withdrawing substituents in fluorobenzene, 1,4 di- fluorobenzene, and benzonitrile on their solvation by up to four HCN ligands, and compared it to previous work done to determine the solvation chemistry of benzene and phenylacetylene by HCN. We report here the observed increase in the binding of the HCN molecule to the aromatic ring as the electronegativity of the substituent increased. We also show in this dissertation, DFT calculations that reveal the formation of both hydrogen-bonded and electrostatic isomers, of similar energies for each addition to the ions respectively. The catalytic activity of the 1st and 2nd row TM ions towards the polymerization of acetylene done using the reflectron time of flight mass spectrometry and DFT calculations is also reported in this dissertation. We explain the variation in the observed trend in C-H/C-C activity of these ions. We also report the formation of carbide complexes by Zr+, Nb+, and Mo+, with the acetylene ligands, and show the thermodynamic considerations that influence the formation of these dehydrogenated ion-ligand complexes. Finally, we show in this dissertation, a novel ionization technique that we employed to generate ions that could be relevant to the interstellar and circumstellar media using the reflectron time of flight mass spectrometry.

In this thesis, multiple ionisation processes of free atoms and molecules upon single photon absorption are studied by means of a versatile multi-electron-ion coincidence spectroscopy method based on a magnetic bottle, primarily in combination with synchrotron radiation. The latter offered the possibility to access not only valence but also core levels, revealing processes, which promote the target systems into different charge states. One study focuses on double and triple ionisation processes of acetaldehyde (ethanal) in the valence region as well as single and double Auger decay of initial 1s core vacancies. The latter are investigated site-selectively for the two chemically different carbon atoms of acetaldehyde, scrutinising theoretical predictions specifically made for that system. A related study concentrates on core-valence double ionisation spectra of acetaldehyde, which have been investigated in the light of a previously established empirical model, and which have been used as test cases for analysing this kind of spectra by means of quantum chemical electronic structure methods of increasing sophistication. A third study investigates site-specific fragmentation upon 1s photoionisation of acetaldehyde using a magnetic bottle augmented with an in-line ion time-of-flight mass spectrometer. Experimental evidence is presented that bond rupture occurs with highest probability in the vicinity of the initial charge localisation and possible mechanisms are discussed. A site-specificity parameter P∆ is introduced to show that differences in fragmentation behavior between initial ionisations at chemically different carbon atoms probably persist even for identical internal energy contents in the nascent dications. In another study where both electrons and ions from Auger decay of core-excited and core-ionised states of CO2 are detected in coincidence, it is confirmed that O2+ is formed specifically in Auger decay from the C1s → π* and O1s → π* resonances, suggesting a decisive role of the π* orbital in the molecular rearrangement. Also, the molecular rearrangement is found to occur by bending in the resonant states, and O2+ is produced by both single and double Auger decay. A new version of the multi-electron-ion coincidence method, where the ion time-of-flight spectrometer is mounted perpendicularly to the electron flight tube, which affects less the electron resolution and which allows for position sensitive detection of the ions, is employed in combination with tunable soft X-rays to reveal the branching ratios to final Xen+ states with 2 &lt; n &lt; 9 from pure 4d-1, 4p-1, 4s-1, 3d-1 and 3p-1 Xe+ hole states. The coincident electron spectra give information on the Auger cascade pathways. / <p>Byte av lokal vid disputation till Polhemssalen.</p>

[pt] Um espectrômetro de massa tipo tempo-de-vôo, montado no Laboratório Nacional de Luz Síncrotron (Campinas - SP), foi utilizado para analisar os íons dessorvidos de uma amostra de amônia condensada (temperaturas de análise: 25 a 150 K) ao ser impactada por fragmentos de fissão do 252Cf. O espectrômetro permite identificar e determinar as abundâncias das espécies iônicas dessorvidas. Quanto à parte teórica, foram feitos cálculos para determinar as estruturas mais estáveis dos agregados de NH3 e para determinar suas dinâmicas de emissão de íons secundários observados na parte experimental. A amônia foi escolhida por sua semelhança com a água, uma molécula muito bem estudada. Outra razão é o atual interesse em determinar a formação de compostos orgânicos nas superfícies de corpos interestelares, uma vez que está comprovada a presença da amônia naquelas superfícies. Nos espectros obtidos observa-se a formação de agregados de amônia que podem ser representados por (NH3)nNHm ± com n = 0-30 e m = 0-5, para íons positivos, e com n = 0- 3 para íons negativos. Uma forma de evidenciar a possibilidade de formação de novos compostos foi realizar experiências com a mistura NH3-CO, com a mesma montagem experimental utilizada para a amônia. Observa-se no espectro obtido (antes da sublimação do CO a 30 K) linhas de massa resultantes de reações primárias que correspondem a íons moleculares híbridos com estrutura CnOmHl+.Os cálculos teóricos referentes às estruturas dos agregados foram realizados través do programa Jaguar 5.5 e Jaguar 6.0. O objetivo é determinar as estruturas mais estáveis dos agregados iônicos da amônia através da teoria DFT (Teoria do Funcional de Densidade) por meio da minimização da energia. Encontrou-se uma relação direta entre as estabilidades determinadas e as abundâncias relativas no espectro de massa. Finalmente foram realizados cálculos com o modelo teórico de dessorção iônica induzida por elétrons. Os resultados de distribuição de velocidades e energias foram comparados com os dados experimentais dos agregados da amônia (n = 0, 4), apresentando uma concordância razoável em valor absoluto, mas moderada em forma. / [en] A time-of-flight mass spectrometer, mounted at the Laboratório National de Luz Síncrotron (Campinas - SP), was used to analyze desorbed ions of a condensed ammonia sample (analyzing temperatures: 25 - 150 K) being impacted by 252Cf fission fragments . The spectrometer allows identifying and determining the relative yields of ionic desorbed species. Besides, it had been made theoretical calculations to determine the most stable cluster structures as well as to determine the emission dynamics of NH3 clusters observed in the experimental part. The ammonia was chosen because of its similarity with the water molecule (very well studied). Another reason is the current interest in determining the organic compounds formation in the interstellar surfaces, now that it is proven the presence of ammonia in those surfaces. The measured spectra show the formation of ammonia clusters that can be represented by (NH3)nNHm ± with n = 0 - 30 and m = 0 - 5 for positive ions, and n = 0 - 3 for negative ones. One way to evidence the formation possibility of new compound is to perform experiments with CO-NH3 mixture samples, using the same experimental set up used for the ammonia. In the spectrum measured before CO sublimation (30 K), mass lines, product of primary reactions, corresponding to hybrid molecular ions having the CnOmHl + structure were observed. Theoretical calculations referring to cluster structures had been carried out using the programs Jaguar 5,5 and Jaguar 6.0. The objective is to determine the most stable structures of the ammonia clusters through the Density Functional Theory (DFT) by means of energy minimizations. A direct relation between the computed stabilities and the relative abundances in the mass spectra was found. Finally calculations with the Secondary Electron Induced Desorption (SEID) model had been carried out. Results of velocity and energy distributions had been compared with the experimental data of ammonia clusters (n = 0, 4), presenting a good agreement in absolute values but moderate agreement in shape.

A espectrometria de massas baseada na tecnologia MALDI-TOF (do inglês, matrix-assisted laser desorption ionization-time of flight) (MALDI-TOF MS) tem sido cada vez mais incorporada à rotina de identificações microbiológicas nos laboratórios farmacêuticos de controle de qualidade, principalmente para as atividades do Programa de Monitoramento Ambiental de Salas Limpas. Isso porque o longo tempo necessário para a obtenção dos resultados por meio de métodos convencionais tem incentivado a procura por técnicas que permitam métodos rápidos. O objetivo deste trabalho foi avaliar a adequação da técnica MALDI-TOF MS para a identificação de bactérias isoladas do ambiente de salas limpas utilizadas em algumas etapas da produção de uma vacina viral. Treze espécies bacterianas conhecidas, normalmente isoladas das salas limpas estudadas, e cinco cepas ATCC foram identificadas pela técnica MALDI-TOF MS e por uma técnica bioquímica (BBL Crystal®). O desempenho da técnica MALDI-TOF MS foi superior ao da técnica bioquímica na identificação correta das espécies bacterianas (88,89% e 38,89%, respectivamente) e produziu menos identificações não confiáveis (5,55% e 22,22%, respectivamente). Os resultados evidenciaram que a técnica MALDI-TOF MS pode ser implementada para identificação rotineira de bactérias em um laboratório de controle de qualidade farmacêutico. Entretanto, a dependência de bases de dados exige estudos adicionais de isolados não identificados e, se apropriado, a adição destes a uma base de dados interna. O aperfeiçoamento de métodos de identificação microbiana é muito relevante no contexto de salas limpas, pois permitem ações corretivas e proativas essenciais para garantir a segurança microbiológica do processamento asséptico. / Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been increasingly introduced in routine microbiological identifications of pharmaceutical quality control laboratories, mainly for the activities of the Environmental Monitoring Program of Clean Rooms. The long time needed to obtain the results through conventional methods has stimulated the search for techniques that allow rapid methods, as MALDI-TOF MS. Thus, the objective of this work was to evaluate the suitability of the MALDI-TOF MS technique for the identification of bacteria isolated from the environment of clean rooms used in some stages of the production of a viral vaccine. Thirteen bacterial species commonly isolated from clean rooms studied and five strains ATCC were identified by MALDI-TOF MS technique and by a biochemical technique (BBL Crystal® System). Performance of MALDI-TOF MS was better than biochemical technique for correct species identifications (88.89% and 38.89%, respectively) and produced fewer unreliable identifications (5.55% and 22.22%, respectively). MALDI-TOF MS can be implemented for routine identification of bacteria in a pharmaceutical quality control laboratory. However, as a database-dependent system, maybe some isolated not identified by this technique must be additionally studied and, if appropriate, added to an in-house database.

No presente trabalho é apresentado um conjunto de medidas de seção de choque do processo de fusão nuclear nos sistemas ANTPOT. 12 C + ANTPOT. 63, 65 CU, em um intervalo de energia correspondente à 0.91.8 vezes a barreira coulombiana. O método experimental utilizado foi a detecção dos resíduos de evaporação através da técnica de tempo de vôo, acoplado à um defletor eletrostático para separar as partículas provenientes do espalhamento elástico dos produtos de fusão. As vantagens e limitações do método são discutidas em detalhes. As funções de excitação de fusão dos sistemas citados foram analisadas via modelo de penetração de barreira unidimensional , utilizando vários potenciais nucleares. Dessa análise comprovou-se que a secção de choque de fusão é subestimada em energias em torno e abaixo da barreira coulombiana. Nesse sentido foi feito um cálculo, utilizando o código computacional CCFUS, que simula o acoplamento de canais, com a finalidade de descobrir quais canais contribuem para o processo de fusão nuclear em baixas energias. As seções de choque de fusão obtidas foram comparadas com outros sistemas - ANTPOT. 12 C + ANTPOT. 63, 65 CU.- que utilizam os mesmos núcleos-alvo. A comparação revelou que os sistemas ANTPOT. 12 C + ANTPOT. 63, 65 CU possuem o maior aumento de seção de choque de fusão subcoulombiana e esse fato pode estar relacionado à deformação estática do projétil. A comparação das distribuições da velocidade dos resíduos de evaporação para os dois de sistemas revelou um canal intenso para o sistema ANTPOT. 12 C + ANTPOT. 63 CU que não está presente para o outro sistema. / In this work we present cross-section measurements for nuclear fusion in the 12C+ 63,65 Cu system, at 12C energy range from 0.9 to 1.8 times the Coulomb barrier. In order to detect and to obtain the mass identification of the evaporation residues following the fusion process, the time of flight method was adopted in conjunction with an eletrostatic deflector capable of separating the evaporation residues from the beam particles. The limitation and advantadges of this method of measurement are discussed. The excitation functions for the above systems were analysed using the unidimensional barrier penetration model with different nuclear potentials. Theoretical fusion cross-section values obtained from this analysis were systematically smaller than our measured values, in the energy region below the Coulomb barrier. In order to discover which channel enhances the fusion cross-section in this region, a coupled channel calculation was performed, with the aid of CCFUS code. The experimental data for the above reactions were compared with the systems 12C+ 63,65 Cu, measured by our group. In this comparison, It was noted that the systems 12C+ 63,65 Cu have greater fusion cross section below the Coulomb barrier. This fact can be related to the static deformation of 12C. The comparison of velocity spectra of the evaporated residues for the two systems shows that 12C+63Cu has a strong reaction channel that was not present in the 12C+ 65Cu system.

No presente trabalho é apresentado um conjunto de medidas de seção de choque do processo de fusão nuclear nos sistemas ANTPOT. 12 C + ANTPOT. 63, 65 CU, em um intervalo de energia correspondente à 0.91.8 vezes a barreira coulombiana. O método experimental utilizado foi a detecção dos resíduos de evaporação através da técnica de tempo de vôo, acoplado à um defletor eletrostático para separar as partículas provenientes do espalhamento elástico dos produtos de fusão. As vantagens e limitações do método são discutidas em detalhes. As funções de excitação de fusão dos sistemas citados foram analisadas via modelo de penetração de barreira unidimensional , utilizando vários potenciais nucleares. Dessa análise comprovou-se que a secção de choque de fusão é subestimada em energias em torno e abaixo da barreira coulombiana. Nesse sentido foi feito um cálculo, utilizando o código computacional CCFUS, que simula o acoplamento de canais, com a finalidade de descobrir quais canais contribuem para o processo de fusão nuclear em baixas energias. As seções de choque de fusão obtidas foram comparadas com outros sistemas - ANTPOT. 12 C + ANTPOT. 63, 65 CU.- que utilizam os mesmos núcleos-alvo. A comparação revelou que os sistemas ANTPOT. 12 C + ANTPOT. 63, 65 CU possuem o maior aumento de seção de choque de fusão subcoulombiana e esse fato pode estar relacionado à deformação estática do projétil. A comparação das distribuições da velocidade dos resíduos de evaporação para os dois de sistemas revelou um canal intenso para o sistema ANTPOT. 12 C + ANTPOT. 63 CU que não está presente para o outro sistema. / In this work we present cross-section measurements for nuclear fusion in the 12C+ 63,65 Cu system, at 12C energy range from 0.9 to 1.8 times the Coulomb barrier. In order to detect and to obtain the mass identification of the evaporation residues following the fusion process, the time of flight method was adopted in conjunction with an eletrostatic deflector capable of separating the evaporation residues from the beam particles. The limitation and advantadges of this method of measurement are discussed. The excitation functions for the above systems were analysed using the unidimensional barrier penetration model with different nuclear potentials. Theoretical fusion cross-section values obtained from this analysis were systematically smaller than our measured values, in the energy region below the Coulomb barrier. In order to discover which channel enhances the fusion cross-section in this region, a coupled channel calculation was performed, with the aid of CCFUS code. The experimental data for the above reactions were compared with the systems 12C+ 63,65 Cu, measured by our group. In this comparison, It was noted that the systems 12C+ 63,65 Cu have greater fusion cross section below the Coulomb barrier. This fact can be related to the static deformation of 12C. The comparison of velocity spectra of the evaporated residues for the two systems shows that 12C+63Cu has a strong reaction channel that was not present in the 12C+ 65Cu system.

Les structures composites intégrant des transducteurs piézoélectriques au cœur de la matière sont utilisées pour leur capacité à modifier leurs propriétés mécaniques en fonction de l’environnement, à contrôler leur intégrité structurale et à interagir avec l’homme ou avec d’autres structures.Ce travail se concentre sur les phases de conception préliminaire des structures composites intelligentes. Ces phases ne représentent que 5% du coût total d’un projet, mais conditionnent 80% du coût final du produit. Les principaux problèmes rencontrés lors de ces phases de conception préliminaire portent sur la détermination des propriétés matériau des transducteurs piézoélectriques et des matériaux composites utilisés, de l'influence de l'emplacement des transducteurs dans la structure ainsi que de l’influence du processus de fabrication, de la température et des endommagements sur le comportement final des structures composites intelligentes.Dans le processus de fabrication développé à l’Université de Technologies Belfort-Montbéliard (UTBM), l’élément-clé est un produit semi-fini appelé “soft layer”. Cette couche permet d’intégrer le réseau de transducteurs piézoélectriques au cœur de la structure composite. Le processus de fabrication de la “soft layer” ainsi que celui des structures intelligentes sont abordés dans cette thèse.Afin de trouver des solutions aux problèmes décrits ci-dessus, deux méthodes de caractérisation de composites intelligents ou adaptatifs sont présentées et utilisées : la méthode dite Resonalyser et la méthode du temps de vol. Après des études expérimentales et une comparaison des résultats obtenus, la méthode du temps de vol a été choisie comme méthode principale en raison de son faible coût de mise en œuvre et du fait qu’il s’agit d’une méthode de caractérisation in-situ. De plus, une nouvelle méthode appelée méthode CMB, basée sur la méthode du temps de vol a été développée afin de pouvoir facilement et rapidement extraire les constantes élastiques, en particulier le coefficient de Poisson.Des analyses expérimentales de sensibilité appliquées aux composites adaptatifs ont été effectuées.Premièrement, l’étude de l’influence de l’emplacement des transducteurs démontre qu’il est nécessaire de tenir compte de la position de la “soft layer” dans la modélisation du comportement de produit final. La position de cette couche dans l’épaisseur du produit a une influence notable sur les fréquences propres ainsi que les amplitudes modales de la structure. Cependant, l’ajout de la “soft layer” n’accroît pas le taux d’amortissement de la structure finale; et sa position dans l’épaisseur n’a aucune influence sur ce taux d’amortissement. La propagation des ondes de Lamb à l’intérieur du composite n’est pas impactée par le “soft layer”.Deuxièmement, l’étude de l’impact du processus de la fabrication nous renseigne sur l’influence notable des divers paramètres de réglage du processus de fabrication sur le comportement final de la structure composite intelligente.Troisièmement, l’étude de l’influence de la température sur des structures constituées de différents matériaux composites montre que le module de Young du produit final décroît quand la température augmente. Mais la diminution du module de Young en fonction de la température est différente selon les et les types de matériaux et les directions des fibres, en particulier pour les structures composites unidirectionnelles. De plus, cette étude montre également la sensibilité de la méthode du temps de vol vis-à-vis de la température. Ce dernier point est par ailleurs consolidé par la comparaison avec des résultats obtenus par une méthode de caractérisation ex-situ standard : l'analyse dynamique de la mécanique (DMA).Enfin, l'étude de l'impact des dommages mécaniques fournit une assez bonne référence pour les recherches futures. De cette façon, il est clair qu’une méthode de temps de vol peut être utilisée dans la surveillance de la santé structurale. / The composite structures embedding piezoelectric implants are developed due to their abilities of modifying mechanical properties according to the environment, of keeping their integrity, of interacting with human beings or with other structures.This study is focused on the preliminary design stages of smart composite structures, which represent only 5% of the total costs of a project, whereas 80% of the life cycle cost are set during the preliminary study phases. The top few problems during the preliminary design of smart composite structures are addressed in this work such as the determination of the material properties of the piezoelectric transducers and composite material used, the influence of transducers location, manufacturing process, temperature and damage on the behavior of the smart composite structures.Due to the manufacturing process developed at the Université de Technologie de Belfort-Montbéliard (UTBM), the most important element is a semi-finished product called “soft layer”. This special layer is used to embed the transducers system into the composite structures. The manufacturing process of “soft layer” as well as the smart composite structures are compiled in this report.In order to solve the problems described above, two characterization methods of composite material (Resonalyser method and Time-of-Flight method (T-o-F method)), are introduced and discussed. After experimental studies and comparing the results of these two methods, the T-o-F method is chosen as the main method for the following studies due to the fact that it is a low-cost and in-situ characterization method. Furthermore, a new method based on the T-o-F method is developed to easily and quickly extract the elastic constants, in particular the Poisson’s ratio.Experimental sensitivity analyses applied to the smart composite structures are performed with respect to the problems describes above. First of all, the study of the influence of transducers location demonstrates that the "soft layer” cannot be neglected to model the behavior of the final product. In particular, the through-the-thickness position has an influence on the eigenfrequencies and the modal amplitudes. However, the "soft layer” does not increase the overall damping ratio of the final structures and the through-the-thickness position of the "soft layer” has no influence on the damping ratios. The Lamb wave propagation inside the composite material is not impacted by the "soft layer”. Secondly, the study of the impact of manufacturing process demonstrates that the impact of variability of parameters due to the manufacturing process is very important on the final response of the structure. Thirdly, the study of the influence of temperature on different kinds of smart composite structures proves that when temperature increases, the Young’s modulus of the smart composites decreases. But the attenuation of Young’s modulus according to temperature is different along different fiber directions, especially for the unidirectional composite structures. Furthermore, in this study, the sensitivity of Time-of-Flight method with respect to temperature is well proved by comparing the results with a traditional method like Dynamic-Mechanical Analysis (DMA). Last but not least, the study of the impact of the mechanical damage gives a quite good reference for the future investigations. Along this way, it is possible to use a Time-of-Flight method in Structural Health Monitoring. In addition, some smart composite structures manufactured by the research team are given and their potential applications are discussed.