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Gurke, Johannes. "Protons and Photons". Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19747.
Pełny tekst źródłaTwo projects are implemented in this work, which share the goal to interconnect acid-base equilibria with the photoreactions of diarylethene (DAE) photoswitches. This task can be divided into two logic questions: How can photochemical equilibria be controlled or rather influenced via an acidic or basic stimulus and how can a photoreaction induce control over an acid-base equilibrium? In the first project, “Acid-Catalyzed Cycloreversion”, an externally tunable thermal back reaction was designed to influence a photochemical equilibrium. Upon addition of catalytic amounts of acid, a closed DAE carrying a fluorenol moiety undergoes facile thermal ring opening. The underlying thermodynamics and kinetics of the entire system have been analyzed experimentally as well as computationally. Appling an excess of acid leads to a complete inhibition of the photoreaction through the introduction of a charge-transfer. My work suggests that acid catalysis provides a useful tool to bypass thermal barriers, potentially usable to efficiently trigger the release of light energy stored in photoswitches. In the second project, entitled “Light-induced pKa Modulation”, a significant pKa change of 2.8 units in an aqueous medium was achieved by connecting two different acid-base equilibria. These thermodynamic equilibria are separated by a high activation barrier, overcome by a photoreaction. The developed system which is based on the incorporation of a 3 H thiazol 2 one moiety into a DAE, shows a strong dependency of the quantum yield and hence, of the photoconversion on the protonation state. Adjusting the pH within the range of the pKa change, a substantial enhancement of the photoconversion is achievable as well as a distinct alteration of the performance of the photoreaction. This effect does not originate from different reaction paths on the ground state potential energy surface (PES), but results presumably from a protonated state dependent difference in the excited PES.
JAFER, RASHIDA. "Laser plasma protons and applications in cancer therapy and proton radiography". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7457.
Pełny tekst źródłaPilcher, John Victor. "Coincident proton decay of the continuum induced by 200 MeV protons on 12C". Doctoral thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/17190.
Pełny tekst źródłaCoincident protons from the reaction ¹²C(p,2p) at an incident proton energy of 200 Me V, have been measured using conventional particle telescopes. Data were acquired at nine pairs of angles (θ₂=20°, 45°, 70°, 95°, 120° and 145° for θ₁ =-20°, and θ₂=35°, 85° and 135° for θ₁ =-45°). An improved model, based on previous theoretical and experimental work, has been proposed to describe the reaction mechanism leading to the observed coincident proton yield from the nuclear continuum. This model considers an initial quasifree nucleon-nucleon interaction - described by a distorted wave impulse approximation (DWIA) treatment - between the incident proton and a single target nucleon, followed by the rescattering of the struck nucleon, which behaves as an intranuclear projectile, from the spectator part of the target nucleus. The validity of the DWIA treatment used in the continuum study, has been tested by analysing the kinematic regions of the coincident proton energy spectra corresponding to the knockout of protons from the outer lp3/2 orbital of ¹²C which do not undergo further interactions with the residual nucleus. Good agreement in shape has been found between the calculated and measured cross sections in the kinematic region of interest to the continuum study. An average spectroscopic factor of 1.1±0.3 was extracted. Except in the -20°,20° case, the DWIA treatment was found to be insensitive to the choice of the initial or final energy prescriptions for the two-body scattering approximation. Nonlocality effects were found to be small, changing the absolute value of spectroscopic factors by a maximum of 20%. Coincident continuum cross sections were extracted from the experimental data corresponding to the detection of protons at the θ₁ angles with energies of 70±5 MeV, 100±5 MeV and 130±5 MeV. Comparisons were made with calculations which modelled the proposed reaction mechanism in terms of a convolution integral over the DWIA cross sections describing the initial quasifree knockout process and experimental inelastic scattering probabilities describing the further multiple scattering interactions undergone by the knocked out nucleons. Good agreement has been found between the normalized calculated and measured continuum cross sections (spectroscopic factors varying from 0.8 to 2.3 between sets of data, depending on the kinematic region sampled and the prescription used for the two-body scattering approximation). It has been shown that contributions from nucleons that are knocked out both in- and out-of-plane in the initial quasifree process should be considered, and that the contribution from neutron knockout in the initial interaction is significant, ranging from 0.13 to 0.62 that of the proton knockout contribution.
Roder, Ana Flávia Vidotti [UNESP]. "Estudo da interação de prótons com alvos não homogêneos, aplicados a tomografia com feixes de prótons". Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/108789.
Pełny tekst źródłaO tratamento do câncer através da irradiação com prótons tem se desenvolvido a amplamente, de maneira que a cada década o número de centros com essa tecnologia aumenta progressivamente. Entretanto, o planejamento da rotina de terapia ainda é realizado com imagens de raios-X, que pode causar incertezas quanto ao posicionamento preciso do feixe de prótons sobre o tumor devido à diferença de comportamento ao interagir com a matéria. Por isso, são necessários estudos que busquem o aprimoramento da tomografia computadorizada com prótons, que tem como principal função, determinar a posição do pico de Bragg com eficiência. Mas para se desenvolver essa técnica é preciso determinar a trajetória exata que a partícula percorre dentro do corpo do paciente, que é possível com simulações baseadas no método de Monte Carlo. Vários programas no mercado utilizam Monte Carlo para diferentes tipos de propósitos, dentre os que são voltados para o transporte do próton, estão: GEANT, FLUKA e MCNPX. Esse último foi o utilizado neste trabalho para avaliar a perturbação no feixe incidente de prótons em um meio heterogêneo, composto por água e material simulador de osso compacto (interfaces perpendiculares ao feixe). Além de um modelo formado por água e PMMA (interfases paralelas ao feixe) para avaliar o uso de fantomas desses materiais. Foram estudadas energia, posição e ângulo de saída dos prótons considerando somente partículas primárias e também para todas as partículas
Cancer treatment by irradiation with protons has been widely developed so that each decade the number of centers based on this technology increases progressively. However, the planning of routine therapy is performed with images of X- rays, which can cause uncertainties as to the precise positioning of the proton beam on the tumor due to the difference in behavior when interacting with matter. Therefore, it is necessary studying the improvement of computed tomography with protons, whose main function, determine the position of the Bragg peak efficiently. Nevertheless, to develop this technique it is necessary to determine the exact path that the particle travels through the patient's body, which is possible with simulations based on Monte Carlo method. There are several programs that use Monte Carlo for different types of purposes, among which are meant for the transport of the proton: GEANT, FLUKA and MCNPX. The third one was used in this work to evaluate the disturbance in the incident beam of protons in a heterogeneous medium composed of water and equipment simulator compact bone (beam direction perpendicular to the interface) and water-PMMA (beam parallel to the interface). The output energy, position and angle of the protons were studied considering only primary particles and for all particles
Tripp, Robert D. "Elastic scattering of high-energy polarized protons by complex nuclei". Berkeley, Ca. : Lawrence Radiation Laboratory, 2975. http://catalog.hathitrust.org/api/volumes/oclc/549450172.html.
Pełny tekst źródłaReinhardt, Sabine. "Detection of laser–accelerated protons". Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-155620.
Pełny tekst źródłaGaland, Marina. "Transport des protons dans l'ionosphère aurorale". Phd thesis, Université Joseph Fourier (Grenoble), 1996. http://tel.archives-ouvertes.fr/tel-00724355.
Pełny tekst źródłaKar, S. "Application of MeV laser-driven protons". Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426792.
Pełny tekst źródłaMooser, Andreas [Verfasser]. "Der g-Faktor des Protons / Andreas Mooser". Mainz : Universitätsbibliothek Mainz, 2014. http://d-nb.info/1051353440/34.
Pełny tekst źródłaJohnson, Samantha. "Optimizing the ion source for polarized protons". Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
Pełny tekst źródłaBezuidenhout, Jacques. "Pre-equilibrium helion emission induced by protons". Thesis, Link to the online version, 2006. http://hdl.handle.net/10019.1/1307.
Pełny tekst źródłaInocente, Guilherme Franco [UNESP]. "Estudo teórico da relação entre número de CT de raios-X e Stopping Power de prótons". Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/87806.
Pełny tekst źródłaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Um dos métodos mais utilizados para tratamento de câncer e o uso da radiação. Nesse contexto surge a terapia com feixes de prótons em frente a radioterapia convencional. Sabe-se que com a protonterapia há mais vantagens para o paciente tratado quando comparada com os métodos mais convencionais. A dose distribuída ao longo do caminho percorrido, principalmente nos tecidos sadios - região vizinha ao tumor, e menor e a acurácia do tratamento é muito melhor. Para a realização do tratamento, o paciente passa por alguns procedimentos e um deles é realizar uma imagem para visualização e localização do volume alvo. O principal método para obter essas imagens e a tomografia computadorizada de raios-X (XCT). Para o tratamento com feixes de prótons essa técnica de imagem pode gerar algumas incertezas. A proposta deste estudo é analisar a viabilidade de se reconstruir imagens geradas a partir da irradiação com feixes de prótons, e com isso diminuir algumas imprecisões, já que ser a o mesmo tipo de radiação para planejamento como tratamento, é também para diminuir drasticamente alguns erros de localização, uma vez que o planejamento poder a ser feito no mesmo local e em instantes antes onde o paciente ser a tratado. Este trabalho tem por finalidade, obter uma rela ção entre a propriedade intrínseca da interação de fótons e prótons com a matéria. Para isso utilizaremos de simulação computacional baseada no método de Monte Carlo, com os códigos SRIM 2008 e MCNPX v.2.5.0, para reconstruir imagens através da técnica utilizada na tomografia computadorizada convencional
The radiation method is one of the most used for cancer treatment. In this context arises therapy with proton beams in front of conventional radiotherapy. It is known that with protontherapy there are more advantages to the patient treatement when compared with more conventional methods. The dose distributed along the path, especially in healthy tissues neighbor the tumor, is smaller and the accuracy of treatment is much better. To carry out the treatment, the patient undergoes a plan through images for visualization and location of the target volume. The main method for obtaining these images is computed tomography X-ray (XCT). For treatment with proton beam this imaging technique can to generate some uncertainties. The purpose of this study is to analyse the feasibility of reconstructing images generated from the irradiation with proton beams, thereby reducing some inaccuracies, as it will be the same type of radiation as treatment planning, and also to drastically reduce some errors location, since the planning can be done at the same place and just before where the patient is treated. This study aims to obtain a relationship between the intrinsic property of the interaction of photons and protons with matter. For this we use computational simulation based on Monte Carlo method with the code SRIM 2008 and MCNPX v.2.5.0, to reconstruct images using the technique used in conventional computed tomography
Inocente, Guilherme Franco. "Estudo teórico da relação entre número de CT de raios-X e Stopping Power de prótons /". Botucatu, 2012. http://hdl.handle.net/11449/87806.
Pełny tekst źródłaBanca: Roberto Morato Fernandez
Banca: João Dias de Toledo Arruda Neto
Resumo: Um dos métodos mais utilizados para tratamento de câncer e o uso da radiação. Nesse contexto surge a terapia com feixes de prótons em frente a radioterapia convencional. Sabe-se que com a protonterapia há mais vantagens para o paciente tratado quando comparada com os métodos mais convencionais. A dose distribuída ao longo do caminho percorrido, principalmente nos tecidos sadios - região vizinha ao tumor, e menor e a acurácia do tratamento é muito melhor. Para a realização do tratamento, o paciente passa por alguns procedimentos e um deles é realizar uma imagem para visualização e localização do volume alvo. O principal método para obter essas imagens e a tomografia computadorizada de raios-X (XCT). Para o tratamento com feixes de prótons essa técnica de imagem pode gerar algumas incertezas. A proposta deste estudo é analisar a viabilidade de se reconstruir imagens geradas a partir da irradiação com feixes de prótons, e com isso diminuir algumas imprecisões, já que ser a o mesmo tipo de radiação para planejamento como tratamento, é também para diminuir drasticamente alguns erros de localização, uma vez que o planejamento poder a ser feito no mesmo local e em instantes antes onde o paciente ser a tratado. Este trabalho tem por finalidade, obter uma rela ção entre a propriedade intrínseca da interação de fótons e prótons com a matéria. Para isso utilizaremos de simulação computacional baseada no método de Monte Carlo, com os códigos SRIM 2008 e MCNPX v.2.5.0, para reconstruir imagens através da técnica utilizada na tomografia computadorizada convencional
Abstract: The radiation method is one of the most used for cancer treatment. In this context arises therapy with proton beams in front of conventional radiotherapy. It is known that with protontherapy there are more advantages to the patient treatement when compared with more conventional methods. The dose distributed along the path, especially in healthy tissues ���� neighbor the tumor, is smaller and the accuracy of treatment is much better. To carry out the treatment, the patient undergoes a plan through images for visualization and location of the target volume. The main method for obtaining these images is computed tomography X-ray (XCT). For treatment with proton beam this imaging technique can to generate some uncertainties. The purpose of this study is to analyse the feasibility of reconstructing images generated from the irradiation with proton beams, thereby reducing some inaccuracies, as it will be the same type of radiation as treatment planning, and also to drastically reduce some errors location, since the planning can be done at the same place and just before where the patient is treated. This study aims to obtain a relationship between the intrinsic property of the interaction of photons and protons with matter. For this we use computational simulation based on Monte Carlo method with the code SRIM 2008 and MCNPX v.2.5.0, to reconstruct images using the technique used in conventional computed tomography
Mestre
Driant, Thomas. "On the role of protons in the reactivation of acetylcholinesterase : quantum and molecular mechanics studies". Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066218/document.
Pełny tekst źródłaThe project of this PhD was to investigate the reactivation process and the active site of nerve agent inhibited AChE by computational methodologies to gain insight about the rational design of new reactivators. An initial truncated QM model study provided some insight in the necessary compensation of Glu334 by the enzyme. It also confirmed the role of the oxyanionic hole in the stabilization of the transition state of the reactivation. QM/MM simulations of the reactivation with classical reactivator 2-PAM, as well as two non-pyridinium reactivators, were performed. It was shown that Glu202, a residue near the catalytic triad of AChE, needs to be protonated for the reactivation to occur. Those simulations also showed that the reactivator can be deprotonated in the active site of AChE by His447. Non-pyridinium reactivator were found to have a greater nucleophilicity than 2-PAM and, for one of them, to be easily deprotonated in the active site. Our results indicate that the capacity of a reactivator to be deprotonated in the active site of the enzyme is more important than its nucleophilicity. Finally, a proton relay mechanism was identified through QM/MM and EVB simulations. It involves two glutamate residues, Glu450 and Glu452, positioned behind the active site. The potential for these two residues to be transiently protonated and thus involved in a proton relay was confirmed by CpHMD simulations. This proton relay mechanism relies on the N-protonation of an amide which is a novel mechanism
Audirac, Laurent. "Etude de la radioactivité 2-protons de 45Fe avec une chambre à projection temporelle". Phd thesis, Bordeaux 1, 2011. http://tel.archives-ouvertes.fr/tel-00659079.
Pełny tekst źródłaMussgiller, Andreas. "Identification and tracking of low energy spectator protons". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983453950.
Pełny tekst źródłaHarwin, Michael John. "Soft hadron photoproduction at 20 GeV from protons". Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38029.
Pełny tekst źródłaKRAUSER, SABINE. "L'omeprazole, un inhibiteur de la pompe a protons". Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR15073.
Pełny tekst źródłaBerthet, Patrick. "Étude de la production cohérente de mésons [pi et êta] à grand transfert dans les collisions protons-deutons". Paris 11, 1986. http://www.theses.fr/1986PA112071.
Pełny tekst źródłaThe production of [pi° and eta] mesons in the reactions [pd-> 3 Hepi° and pd-> 3 Heeta] has been studied at very backward angles for proton kinetic energies ranging from 0,92 to 2,6 GeV. The 3 He produced in these experiments were detected with the SPES 4 spectrometer at the labratoire national Saturne
Blaikley, Helen. "Measurement of the proton structure from 1996 and 1997 radiative ep scattering data using the ZEUS detector". Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301844.
Pełny tekst źródłaVanzella, Daniel Augusto Turolla [UNESP]. "Férmions em referenciais acelerados: desintegração de prótons e outras aplicações". Universidade Estadual Paulista (UNESP), 2001. http://hdl.handle.net/11449/102503.
Pełny tekst źródłaFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Ao longo desta tese, modelamos alguns processos de Física de Partículas governados pela interação fraca introduzindo, para isso, o conceito de correntes semi-clássicas e acoplando-as a campos quânticos fermiônicos. Dessa maneira, analisamos a influência que a aceleração exerce sobre as desinte- grações de prótons e nêutrons segundo os processos P'SETA'NEPOT.+'''nü'IND.E' e N'SETA'PEPOT.-'''nü'IND.E', respectivamente, assim como descritas por observadores inerciais. Entre outros resultados, obtemos o tempo próprio de vida média de prótons e nêutrons uniformemente acelerados. Embora possa ser desprezada sob condições terrestres, mostramos que a desintegração de prótons acelerados e potencialmente importante em algumas situações astrofísicas. Utilizando técnicas de Teoria Quântica de Campos em Espaços Curvos, analisamos a desintegração de prótons e nêutrons uniformemente acelerados também sob a ótica de observadores co-acelerados. Uma vez assumida a validade do efeito Fulling-Davies-Unruh, conseguimos reconciliar as descrições inercial e co-acelerada para as transições P'SETA'N e N'SETA'P, embora as interpretações em termos de partículas elementares sejam drasticamente distintas. Como veremos, um ingrediente crucial para se obter tal consistência é a existência de partículas massivas livres que violam a equação de energia de Einstein, i.e., partículas livres com massa de repouso m e energia total E< M'CPOT.2', que é um aspecto geral da quantização em espaços curvos e referenciais acelerados. Abordamos, então,a questão da detecção de tais partículas, utilizando, para isso, uma corrente escalar semi-clássica como detector. Por fim, consideramos, utilizando um modelo simplificado, a influência que o campo gravitacional de estrelas de nêutrons pode exercer sobre o processo de neutronização P'Epot.-''SETA''ETA''nüIND.E' que é um...
In the present thesis, we model some weak interaction processes of Particle Physics by defining the concept of semiclassical currents and coupling them to fermionic quantum fields. In this context, we analyze the influence of acceleration on proton and neutron decays due to processes P'SETA'NEPOT.+'''nü'IND.E'and N'SETA'PEPOT.-'''nü'IND.E, respectively, as described by inertial observers. Among other results, we obtain the mean proper lifetime of uniformly accelerated protons and neutrons. Although it can be neglected under Earth conditions, we show that the decay of accelerated protons is potentially important in some astrophysical situations. By using Quantum-Field-Theory-in-Curved-Spacetimes technics, we analyze also the decay of uniformly accelerated protons and neutrons according to coaccelerated observers. Assuming the validity of the Fulling-davies-Unruh effect, we are able to reconcile and coaccelerated descriptions of P'SETA'N e N'SETA'P transitions, even though their elementary particle interpretations are pretty distinct. As we shall see, a crucial ingredient to obtain such consistency is the exixtence of free massive particles which violate the Einstein energy euation, i.e., free particles with mass m E< M'CPOT.2', which is a general feature of quantization in curved spacetimes and accelerated frames. Thus, we analyze the detectability of such particles using a semiclassical sclar current as detectot device. Finally, we consider, using a toy model, the influence of the gravitational field of neutron stars on the neutronization process P'Epot.-''SETA''ETA''nüIND.E' which is an important cooling mechanism...(Complete abstract click electronic access below)
Cobigo, Yann. "Production de J/[psi] dans les collisions proton-proton et deuton-or à 200 GeV dans le centre de masse nucléon-nucléon". Lyon 1, 2004. http://www.theses.fr/2004LYO10156.
Pełny tekst źródłaLiu, Que. "The source and fate of protons in postischemic hearts". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0013/NQ59623.pdf.
Pełny tekst źródłaBenjaminsen, Bjørn Eirik. "Nanoflow of Protons and Water in Polymer Electrolyte Membranes". Thesis, Norges Teknisk-Naturvitenskaplige Universitet, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-20835.
Pełny tekst źródłaLantz, Mattias. "Investigations of Reaction Cross Sections for Protons and 3He". Doctoral thesis, Uppsala universitet, Institutionen för kärn- och partikelfysik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5813.
Pełny tekst źródłaHumières, Emmanuel d'. "Accélération de protons par interaction laser-plasma et applications". Paris 6, 2006. http://www.theses.fr/2006PA066047.
Pełny tekst źródłaGARDIC, FRANCK. "Etude de l'interaction des protons avec les composants microelectroniques". Paris 6, 1996. http://www.theses.fr/1996PA066155.
Pełny tekst źródłaEsteves, López Natalia. "Etude du transfert de protons dans les systèmes moléculaires". Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0178/document.
Pełny tekst źródłaA major challenge to generate green energy from sunlight would be to split water which is a ubiquitous molecule to produce H$_2$. However VUV light (6.66 eV) is needed to dissociate the H-OH covalent bond. In this work we will show that it is possible to dissociate water via photo-sensitisation with UVC light, using a simple organic catalyst.Recently, ab-initio calculations predict that pyridine (Py) can act as a photo-catalyst to split water by absorption of a UV photon, following the reaction:Py-H$_2$O + h$\nu_1 \to$ Py*-H$_2$O $\to$ PyH$\bullet$ + OH$\bullet$ To test this prediction, we studied the Py-H$_2$O complex in isolated cold molecular cluster and the system trapped in cryogenic matrices. We characterized the electronic spectroscopy of the PyH$\bullet$ in the gas phase and we evidenced the reaction through UV excitation of Py-(H$_2$O) $_n$ clusters. We have evidenced that the reaction leads PyH$\bullet$ as photoproduct of the reaction. We also evidenced that the surrounding conditions play an important role in the reaction.We have demonstrated that the UV excitation of Py-water clusters leads to the formation of PyH$\bullet$, thus we have evidenced the water splitting reaction. The last step of the process, that is the regeneration of the catalyst by absorption of a second UV photon (PyH$\bullet$ + h$\nu \to$ Py + H$\bullet$) has been studied and it seems that only hot PyH$\bullet$ molecules are able to follow this channel. In the present, we are studying other aromatic molecules which are expected to lead the photochemical dissociation of water
Esteves, López Natalia. "Etude du transfert de protons dans les systèmes moléculaires". Electronic Thesis or Diss., Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0178.
Pełny tekst źródłaA major challenge to generate green energy from sunlight would be to split water which is a ubiquitous molecule to produce H₂. However VUV light (6.66 eV) is needed to dissociate the H-OH covalent bond. In this work we will show that it is possible to dissociate water via photo-sensitisation with UVC light, using a simple organic catalyst.Recently, ab-initio calculations predict that pyridine (Py) can act as a photo-catalyst to split water by absorption of a UV photon, following the reaction: Py-H₂O + hν₁ → Py*-H₂O → PyH• + OH• To test this prediction, we studied the Py-H₂O complex in isolated cold molecular cluster and the system trapped in cryogenic matrices. We characterized the electronic spectroscopy of the PyH• in the gas phase and we evidenced the reaction through UV excitation of Py-(H₂O)n clusters. We have evidenced that the reaction leads PyH• as photoproduct of the reaction. We also evidenced that the surrounding conditions play an important role in the reaction.We have demonstrated that the UV excitation of Py-water clusters leads to the formation of PyH•, thus we have evidenced the water splitting reaction. The last step of the process, that is the regeneration of the catalyst by absorption of a second UV photon (PyH• + hν → Py + H•) has been studied and it seems that only hot PyH• molecules are able to follow this channel. In the present, we are studying other aromatic molecules which are expected to lead the photochemical dissociation of water
OLIVEIRA, HENRIQUE B. de. "Modelos analiticos para o desenvolvimento de alvos metalicos de alta performance irradiados nos ciclotrons cyclone 30 e cyclone 18 do IPEN-CNEN/SP". reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9494.
Pełny tekst źródłaMade available in DSpace on 2014-10-09T13:59:13Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Baccou, Claire. "Initiation de réactions nucléaires par des protons accélérés par laser". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX016/document.
Pełny tekst źródłaThe recent development of high-intensity laser beams has stimulated the advent of many schemes to produce nuclear reactions by laser. Laser pulses with intensity higher than 1018 W.cm-2 can particularly be used to accelerate proton and ion beams with interesting characteristics such as a broad spectrum, a short duration (~ 10ps), a large number of particles per picosecond and a high energy cut-off, up to tens MeV. Thus, nuclear reactions with resonances close to hundreds keV can be initiated, such as the p-11B fusion reaction which releases 8.7MeV and three alpha particles, or, such as threshold reactions with produce positron emitters, used in nuclear medicine. This thesis was dedicated to the development of an experimental platform at the ELFIE laser facility, at LULI (Ecole Polytechnique, France) to study the production of nuclear reactions using the following scheme: a proton beam is accelerated by the TNSA mechanism on a first target, and sent into a boron target to induce nuclear reactions. A second laser beam can be used to ionize and heat the boron target. A set of complementary diagnostics has been developed to measure and characterize the reaction products. Several parameters such as the proton flux, the proton spectrum, the boron target state (solid or plasma) and its composition were studied in order to identify the physics parameters that optimize the number of reactions. The understanding of the physics that govern the production of reactions in this scheme is necessary to consider applications in medicine or in fusion schemes, to produce energy
André, Philippe. "Étude et modélisation des effets des protons sur les photopiles Ga Al As (p) / Ga As (n)". Toulouse, ENSAE, 1985. http://www.theses.fr/1985ESAE0011.
Pełny tekst źródłaDesfontaines, Hervé. "Etude du transport de protons par modes collectifs dans les chaînes à liaisons hydrogènes". Dijon, 1989. http://www.theses.fr/1989DIJOS019.
Pełny tekst źródłaSteyn, Douw. "Radiative proton capture to second harmonic giant dipole states in ¹³N". Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/17288.
Pełny tekst źródłaAngular distributions have been measured for the radiative proton capture reaction ¹²C(p,ϒ)¹³N at beam energies from 40 to 54 MeV. Measurements were made with the new, large anticoincidence-shielded spectrometer HA GAR at angles from 30° to 150° to the beam direction. Differential and total cross-sections have been calculated from these data, and show evidence for resonant behaviour for the transitions to the ground state, the first excited state, and the unresolved second and third excited states. The total cross-sections for these transitions peak at a proton energy of about 46 MeV which is twice the centroid energy of the Giant Dipole Resonance (GDR) based on the ground state of ¹³N.
Marchlenski, Donald G. "Helium-three and proton radiative capture studies at intermediate energies /". The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487332636475414.
Pełny tekst źródłaSilva, Marcelo. "Carga superficial de agregados nanoestruturados". Florianópolis, SC, 2011. http://repositorio.ufsc.br/xmlui/handle/123456789/95447.
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A adição de sais em soluções de surfactantes dipolares iônicos promove incorporação específica de ânions nas superfícies das micelas. Essa incorporação gera um caráter aniônico nas micelas que atrai eletrostaticamente íons H3O+ para a superfície micelar. A ordem de incorporação segue a série de Hofmeister e é ClO4- > Br- > Cl- > OH-. Este efeito atualmente é chamado de efeito camaleão. No presente trabalho calculou-se e usou-se o equilíbrio de protonação do 1-naftol (1NOH, pKa* = 2,47 e pKa = 9,33) e 2-naftol (2NOH, pKa* = 2,26 e pKa = 9,71), para investigar mudanças de pH ocorridas em superfícies de agregados micelares nanoestruturados formados por surfactantes dipolares iônicos de 1-propanosulfonato-N-tetradecil-N,N-dimetilamonio (SB3-14). Observou-se mudanças de mais de uma unidade de pH na fase micelar da SB3-14 pela adição de 0,04 M de NaClO4 e, as mudanças foram comparadas com aquelas na presença do surfactante aniônico dodecilsulfato de sódio, SDS. Cálculos teóricos das sondas 1NOH e 2NOH mostram que essas sondas adquirem uma acidez elevada no estado excitado. A reação de transferência de próton entre a sonda 2NOH* (no estado excitado) e diferentes ânions orgânicos como acetato, propionato, formiato, trifluoracetato e perclorato, foi estudada em água. As constantes de velocidades encontradas foram de kPT = 3,8 x 108 M-1 s-1 para os íons acetato, propionato e formiato que são derivados de ácidos com pKa > 2,26 e não observou-se reação para os íons trifluoracetato e ClO4- que possuem pKa(s) < 2,26. Também, foi estudada a reação de transferência de próton no estado excitado entre a sonda 2NOH e o íon acetato em D2O (KPT 2,1 x108 M-1 s-1), mostrando que a reação ocorre com participação de molécula(s) de solvente. Em soluções micelares de SB3-14 obteve-se kPT = 0,99 x 108 M-1 s-1, mostrando que a microviscosidade da micela dificulta as reações de transferência de prótons. Nas reações de transferência de prótons entre o íon H2PO4- e os ácidos 1-naftóico (1COOH) e 2-naftóico (2COOH) obtiveram-se, especificamente para o 2COOH um valor de kPT = 1,77 x 10-8 M-1 s-1, e, para o 1COOH o valor de kPT não foi quantificado, já que a reação procede numa escala de tempo menor que 1-2 nanosegundos (ns).
The addition of salts in zwiterionic micellar solutions promotes specific anion incorporation in the micellar surface. The incorporation results in an anionic character in the micelles which in turn electrostatically attracts ions H3O+ to the micellar surface. The order of incorporation follows the Hofmeister series ClO4-> Br-> Cl-> OH- and this effect is called the chameleon effect. In the present work was calculated the acid dissociation constants of 1-naphthol (1NOH, pKa*= 2.47 and pKa = 9.33) and 2-naphthol (2NOH, pKa* = 2.26 and pKa = pKa 9.71), to investigate changes in pH at the surfaces of nanostructured micellar aggregates formed by the zwiterionic surfactant N-tetradecyl-N,N-dimethylammonio-1-propanesulfonate, SB3-14. Changes of more than one pH unit at the micellar surface of SB3-14 were promoted by addition of 0.04 M NaClO4 and the results were compared with those in the presence of the anionic sodium dodecyl sulfate surfactant (SDS). Theoretical calculations of the probes 1NOH and 2NOH, showed that these probes become highly acidic in the excited state. Proton transfer reaction between the probe 2NOH * (excited state) and various organic anions such as acetate, propionate, formiate, trifluoroacetate and ClO4- were studied in water. The rate constant kPT = 3.8 x 108 M-1 s-1 was found for acetate, propionate and formate anions, all of which have pKa > 2,26 and, no reaction was detected for both trifluoracetate and ClO4-, which have pKa < 2,26. The rate constant for the proton transfer reaction in the excited state between acetate ion and 2NOH in D2O (kPT = 2.1 x108 M-1 s-1) is slower than the rate constant observed in water, showing that this reaction occurs with participation of the solvent. In micellar solutions of SB3-14, kPT = 0.99 x 108 M-1 s-1, showing that the microscopic viscosity of the SB3-14 micelle decreases the rate of the reaction. The proton transfer reaction between 2-naphthoic acid (2COOH) and the H2PO4- ion proceeds with kPT = 1.77 x10-8 M-1 s-1, and that of the 1COOH probe is still faster. The value of kPT could not be quantified because the temporal resolution (1-2 ns) is not sufficient to follow the reaction.
Auduc, Stéphane. "Mesure de sections efficaces doublement différentielles de production de protons induites par un faisceau de protons de 62,9 MeV sur une cible de 208Pb". Nantes, 2001. http://www.theses.fr/2001NANT2089.
Pełny tekst źródłaIn the actual context of long life nuclear waste's future, three ways of research have been decided. One of them is about the separation-transmutation of wastes This process uses a sub-critical reactor feed in neutrons by a proton accelerator which irradiate a spallation target. The neutron flux entertains the reactor criticality and, in the same time, allows the transmutation of the wastes placed inside
DOLOC, CRISTIAN MIRCEA. "Etude trajectographique de protons thermonucleaires : application a l'interaction entre les protons de fusion et les ondes injectees a la frequence hybride sur tore-supra". Orléans, 1995. http://www.theses.fr/1995ORLE2011.
Pełny tekst źródłaDieval, Catherine. "The solar wind protons inside the induced magnetosphere of Mars". Licentiate thesis, Luleå tekniska universitet, Rymdteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25726.
Pełny tekst źródłaGodkänd; 2011; 20111101 (catdiv); LICENTIATSEMINARIUM Ämnesområde: Rymdteknik/Space Technology Examinator: Professor Stas Barabash, Institutet för rymdfysik, Kiruna Diskutant: Universitetslektor Maria Hamrin, Umeå universitet Tid: Fredag den 2 december 2011 kl 10.00 Plats: Sal C, Rymdcampus i Kiruna, Luleå tekniska universitet
Reinhardt, Sabine [Verfasser], i Jörg [Akademischer Betreuer] Schreiber. "Detection of laser–accelerated protons / Sabine Reinhardt. Betreuer: Jörg Schreiber". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1033059692/34.
Pełny tekst źródłaMahon, David Francis. "Deeply virtual compton scattering off longitudinally polarised protons at HERMES". Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1924/.
Pełny tekst źródłaHembrador, Sheena (Sheena Marie C. ). "Dosimetry of ¹²⁵Iodine protons for in vivo mouse irradiation study". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/41590.
Pełny tekst źródłaIncludes bibliographical references (leaf 47).
The biological effects of acute, high doses of radiation are well understood. However, the effects of chronic, low doses are not as clear. Mice irradiation experiments to study the correlation of biological effects with chronic low dose rates are underway in order to make conclusions about the effects of low doses. Yet, in order to do so, the level of dose provided to the animals must be determined. This paper examines methods of ascertaining the dose rate delivered to mice by photons from an 125Iodine filled flood phantom source. Two distinct methods were used. First, Optically Stimulated Luminescence (OSL) Dosimeters were placed in an array over an area slightly larger than the irradiation area. The dose equivalent they each reported was recorded weekly. Secondly, a series of simulations were performed using MCNP to calculate the expected dose equivalent reported by those dosimeters. Comparison of the dosimeters' recorded dose to MCNP's calculated dose showed agreement within experimental and statistical uncertainty for 82% of the measurements. This high level of agreement demonstrates that the MCNP simulation approach produces reliable results. After this was shown, other MCNP simulations were performed to determine the dose equivalent to the mice in cages placed above the 125I filled phantom. The simulation showed an average dose equivalent of 656 t 108 mrem per week, with a range of 866 t 33 mrem/week to 399 t 18 mrem/week. The dosimetry methods developed in this report are not unique to this dose level, and can be used in future mouse studies to determine dose rates at other orders of magnitude.
by Sheena Hembrador.
S.B.
Van, der Meulen N. P. (Nicolas Philip). "The cyclotron production of selected radionuclides using medium energy protons". Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/21914.
Pełny tekst źródłaENGLISH ABSTRACT: Radiochemical research involving ion exchange chromatography is of paramount importance to the future of radionuclide production at the Radionuclide Production Group (RPG) of iThemba LABS. It is required for the production of high-activity yields of radionuclides to effectively remove impurities and for the safety of the operators performing such productions. The radiochemical separations of some new products from their target material, as well as experiments to determine whether production is viable, are described. 67Ga is currently being produced at the RPG and makes use of zinc targets. With the production of ultra-pure 67Ga, it was necessary to remove any Fe(III) impurities from the final product, such that it may be possible to label peptides with this product. The use of Amberchrom CG161M for this purpose was found to be satisfactory. Interest was shown in 88Y by an overseas company for the manufacture of sources. While a method involving extraction of the radionuclide and the ion exchange thereof using Chelex 100 chelating resin had been published, problems with the production persisted. Three methods, using ion exchange chromatography, were devised to produce the radionuclide, with two of them being adopted for production purposes. Thick-target nuclear data have also recently been accumulated in collaboration with colleagues from ATOMKI, Debrecen, Hungary. There is a large demand for 82Sr for the manufacture of 82Sr/82Rb generators for medical use. A method was developed to manufacture this radionuclide with thicker (32 g) target material, bombarded in the Vertical Beam Target Station (VBTS), and to separate 82Sr from its target material with the use of Purolite S950 chelating resin. 68Ge/68Ga generators are becoming increasingly important in the world of radiopharmaceuticals. A project to develop a local generator was funded by the Innovation Fund and research was performed to produce 68Ge, such that the generator could be manufactured. This involved bombarding thicker Ga targets in the VBTS and performing the chemical separation using AG MP-1 anion exchange resin. The final product was loaded onto generators, although tests performed on different materials to the ones being marketed are also reported in this work. A project was initiated to study the cluster radioactive decay of 223Ac via 14C and 15N emission. To produce 223Ac for these observations, a Th target was bombarded. The 227Pa was separated from the target material using AG MP-1 macroporous anion exchange resin and used as a source, which decayed to 223Ac. The chemical separation and the drying of the final product onto a source plate were completed within approximately 70 minutes from the end of bombardment. The work was performed in collaboration with JINR, Russia, and University of Milan and INFN, Italy. 133Ba has a half-life of over 10 years and is an expensive radionuclide to produce. It has been used in medical and biological studies and there still appears to be a demand for it. A method was devised, utilizing AG50W-X4 cation exchange resin, to separate 133Ba from its CsCl target material. Agricultural specialists in the past have shown an interest in 28Mg, to determine the uptake of the element in fruit. It has long been regarded by some of the local researchers as an interesting project to investigate. It has been determined that the product can be produced in reasonable quantities using LiCl target material, with ten targets being bombarded in series using a 200 MeV proton beam delivered by the Separated Sector Cyclotron. A method, involving the use of Purolite S950 chelating resin, was devised to separate 28Mg from its target material.
AFRIKAANSE OPSOMMING: Radiochemiese navorsing, wat ioonuitruiling chromatografie behels, is van uiterste belang vir die toekoms van die produksie van radionukliede by die Radionukliedproduksiegroep (RPG) van iThemba LABS. Dit is nodig vir die hoë aktiwiteit opbrengs van radionuklied produkte om onsuiwerhede te verwyder en vir die veiligheid van die operateurs wat die produksies moet uitvoer. Die skeiding van nuwe produkte van hulle skyfmateriaal, sowel as eksperimente om vas te stel of ‘n produksie uitvoerbaar is, word in die werk beskryf. 67Ga word tans by RPG vervaardig en maak gebruik van sink as skyfmateriaal. Vir die produksie van “ultra-suiwer” 67Ga was dit belangrik om enige Fe(III) onsuiwerhede uit die finale produk te verwyder om sodoende peptiede merking te kan uitvoer. Die gebruik van Amberchrom CG161M hars was voldoende vir dié eksperiment. ‘n Oorsese maatskappy het belangstelling getoon in 88Y vir die vervaardiging van bronne. Alhoewel ‘n metode wat die ekstraksie van die radionuklied en die ioonuitruiling daarvan met die gebruik van Chelex 100 chelerende hars reeds gepubliseer was, het probleme met die produksie voortgeduur. Drie metodes is opgestel om 88Y te produseer, waarvan twee van die metodes tans gebruik word vir produksie doeleindes. Dik-skyf kerndata is ook versamel in samewerking met kollegas van ATOMKI, Debrecen, Hongarye. Daar is ‘n groot aanvraag vir 82Sr vir die vervaardiging van 82Sr/82Rb generators vir mediese doeleindes. ‘n Metode is ontwikkel om die radionuklied te vervaardig van dikker skyfmateriaal (32 g), in die Vertikale Bundelstasie gebombardeer, en om 82Sr van sy skyfmateriaal te skei met die gebruik van Purolite S950 chelerende hars. 68Ge/68Ga generators is besig om toenemend belangrik te word in die wêreld van radiofarmasie. iThemba LABS kry baie navrae om die produk te vervaardig. Die projek was ook deel van die voorlegging aan die “Innovation Fund” en ‘n manier is ondersoek om 68Ge te vervaardig, wat benodig word om so ‘n generator te laai. Dik Ga skyfmateriaal word in die Vertikale Bundelstasie gebombardeer en ‘n chemiese skeiding is uitgevoer deur gebruik te maak van AG MP-1 anioonuitruiling hars. Die finale produk is op die generators gelaai vir toetsdoeleindes. Toetse is ook op ‘n ander tipe generator uitgevoer en word in die werk beskryf. ‘n Projek is begin om “cluster” radioaktiewe verval van 223Ac, via 14C en 15N emissie, te bestudeer. ‘n Th-skyf is met protone gebombardeer om die 223Ac te produseer vir die eksperiment. 227Pa is vervaardig en geskei van die skyfmateriaal. Dit is gedoen met die gebruik van AG MP-1 makroporeuse anioonuitruiling hars en drooggemaak op ‘n bronplaat, waar dit verval het na 223Ac. Die chemiese skeiding en die droogmaak van die finale produk op ‘n bronplaat is uitgevoer binne 70 minute na Einde van Bombardering (EVB). Die werk is deel van ‘n samewerking met kollegas van JINR, Rusland, en die Universiteit van Milaan, sowel as INFN, Italië. 133Ba het ‘n halveertyd van oor die tien jaar en is ‘n duur produk om te vervaardig. Dit is al gebruik in mediese en biologiese studies en daar is deesdae ‘n redelike aanvraag daarvoor. ‘n Metode is uitgewerk om 133Ba te skei van die CsCl skyfmateriaal met die gebruik van AG50W-X4 katioonuitruiling hars. Spesialiste in landboustudies het in die verlede belangstelling getoon in 28Mg. Dit word gebruik om die absorpsie van dié element in vrugte te ondersoek. Die produk kan vervaardig word met die gebruik van LiCl skyfmateriaal: tot soveel as tien skywe (agter mekaar) word gebombardeer met ‘n 200 MeV protonbundel te iThemba LABS. ‘n Metode, wat Purolite S950 behels, is daargestel om 28Mg van die skyfmateriaal te skei.
Moison, Jean-Marie. "Contribution à l'étude des semiconducteurs par photoémission à deux protons". Paris 11, 1985. http://www.theses.fr/1985PA112130.
Pełny tekst źródłaWe present here a quantitative evaluation of two-photon photoemission as a probe for the conduction band of semiconductors and the dynamics of electrons in empty states. These states are populated optically, and the excited population is probed by photoemission along its return to equilibrium. The photoelectron flux is here proportional to the square of the photon flux, via a “two-photon yield”. Because of its very low value, the excitation must be provided by high-intensity pulsed lasers and many parasitic phenomena (optical damage, heating, band filling…) had to be evaluated and avoided. Because of its incidence on data interpretation, the electronic structure (Fermi level, vacuum level, surface states, etc) of the surfaces under study, (111)Si and (100)InP, has also been determined in-situ. The quadratic flux law is then clearly checked, and the yield, its variation with photon energy, and the related energy and angular distributions of the photoelectrons are obtained. The microscopic process is discussed on the basis of the “three-step-model” oh photoemission. It is concluded that the actual process is indeed a succession of two optical absorptions which excite then probe an electron population in the conduction band. This population is observed either just after its excitation (“ballistic” electrons) or after its relaxation in a lateral valley, which yields information on the structure of the conduction band and the related densities of states and lifetimes. The influence of the state of the surface on these data reveals processes involving relaxations out of the lateral valley localized at the surface. These processes are correlated to the surface-localized recombination processes which are determined by parallel photoluminescence studies
MEDDAHI, MALIKA. "Effets faisceau-faisceau dans le collisionneur protons-antiprotons du sps". Paris 7, 1991. http://www.theses.fr/1991PA077062.
Pełny tekst źródłaCadet, Ponce Laurette. "Diagnostic par rayonnement synchrotron des faisceaux de protons du LHC". Grenoble INPG, 2002. http://www.theses.fr/2002INPG0093.
Pełny tekst źródłaPoquet, Sandrine. "Un nouvel inhibiteur de la pompe à protons : le prantoprazole". Bordeaux 2, 1998. http://www.theses.fr/1998BOR2P047.
Pełny tekst źródłaKozarev, Kamen Asenov. "Coronal shock acceleration and heliospheric transport of solar energetic protons". Thesis, Boston University, 2013. https://hdl.handle.net/2144/12799.
Pełny tekst źródłaSolar flares and coronal mass ejections (CME) in the Sun's atmosphere produce highly energetic charged particles during violent bursts of activity. Protons, the most numerous and important species of these solar energetic particles (SEP), accelerate and propagate throughout the heliosphere, probing the interplanetary transport conditions. They also present a significant radiation hazard to space operations. Nevertheless, SEP acceleration in the low corona is currently not well constrained and poorly understood. In this dissertation, I examine off-limb extreme ultraviolet (EUV) wave dynamics between 1.3 and 2.0 solar radii in the corona, and I show that the EUV signatures are consistent with CME-driven shocks. Therefore, such shocks may form very low in the corona. I also develop a data-driven model for estimating the maximum energy to which protons may be accelerated in coronal shocks. I apply it to an observed shock and show that it may accelerate protons up to tens of MeV during its fast coronal passage, consistent with in-situ observations. To explore further coronal SEP acceleration by CME-driven shocks, I modify a global, 3D numerical model for interplanetary SEP transport for the coronal conditions, and adapt it to incorporate results from a realistic magnetohydrodynamic coronal and CME model. Furthermore, I apply a diffusive shock acceleration model, which explicitly treats proton energization at traveling shocks, to an MHD simulation of a real CME event. I find that the source population becomes strongly accelerated. In addition, I simulate the proton transport between the Sun and Earth, and find that the modeled fluxes are consistent with particle observations near Earth. Results suggest that CME-driven shocks in the corona may be the primary source of SEPs in solar storms. In addition, conditions along coronal shock fronts vary greatly, influencing the amount of acceleration. Finally, I model the global proton transport between Earth and 5 AU during a very large SEP event. I obtain radial gradients of peak fluxes and radiation doses for space weather applications, and I find that simulated and observed fluxes agree reasonably well. This suggests that most CME shocks are not efficient proton accelerators beyond 1 AU.
Zerguerras, Thomas. "Etude de l'emission proton et de deux protons dans les noyaux légers déficients en neutrons de la région A=20". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2001. http://tel.archives-ouvertes.fr/tel-00002692.
Pełny tekst źródłaLes événements de coïncidence double entre un proton et les noyaux 17F, 16O, 15O, 14O et 18Ne ont été étudiés pour reconstruire les spectres en énergie d'excitation de 18Ne, 17F, 16F, 15F et 19Na. Les masses mesurées sont généralement en bon accord avec les résultats obtenus lors de précédentes expériences. Pour le noyau 18Ne, les distributions angulaires et en énergie d'excitation sont en bon accord avec un modèle de break up. A partir des coïncidences entre un proton et 17Ne, une première mesure expérimentale de l'excès de masse de l'état fondamental de 18Na donne 24,19(0,15)MeV.
L'émission de deux protons depuis des états excités de 17Ne et 18Ne, ainsi que depuis l'état fondamental de 19Mg, a été étudiée à partir des événements de coïncidences entre deux protons et respectivement 15O, 16O et 17Ne. Dans le premier cas, la distribution en angle relatif des deux protons dans le centre de masse a été comparée aux résultats de simulation. L'émission séquentielle depuis un état excité de 17Ne, au-dessus du seuil d'émission proton, via 16F, domine mais une contribution d'émission 2He ne peut pas être exclue. Aucune émission 2He depuis l'état à 1,288MeV de 17Ne ni depuis celui à 6,15MeV dans 18Ne, n'a été observée. Un seul événement de coïncidence entre 17Ne et deux protons a pu être enregistré car la section efficace de la réaction de stripping d'un neutron de 20Mg est plus faible que prévu.
ZERGUERRAS, THOMAS. "Etude de l'emission proton et de deux protons dans les noyaux legers deficients en neutrons de la region a=20". Paris 6, 2001. http://www.theses.fr/2001PA066252.
Pełny tekst źródła