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Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-28T14:15:00Z No. of bitstreams: 1 rafaelfelipecoelhoneves.pdf: 2969229 bytes, checksum: cff09b57af6263220760e29c729a1382 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-07T21:09:40Z (GMT) No. of bitstreams: 1 rafaelfelipecoelhoneves.pdf: 2969229 bytes, checksum: cff09b57af6263220760e29c729a1382 (MD5) / Made available in DSpace on 2017-08-07T21:09:40Z (GMT). No. of bitstreams: 1 rafaelfelipecoelhoneves.pdf: 2969229 bytes, checksum: cff09b57af6263220760e29c729a1382 (MD5) Previous issue date: 2011-07-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Em uma variedade de técnicas espectroscópicas de impacto de elétrons em amostras gasosas, é fundamental utilizar feixes de elétrons de baixas energias focalizados, colimados e monocromatizados. Sua intensidade deve ser tal que seja possível realizar a aquisição de dados em um tempo mínimo, apresentando boa estatística. O requisito da monocromatização é o que garante obter o máximo de informações espectroscópicas de dado espectro. É na região de baixas energias do elétron incidente que ocorrem importantes processos, tais como distorções na nuvem eletrônica do alvo, efeitos de polarização, efeitos de troca, captura eletrônica. Entretanto, é justamente nesta faixa de energia onde se observa maior dificuldade experimental de se trabalhar devido a alta sensibilidade do feixe eletrônico tanto incidente, como espalhado. Neste trabalho, desenvolvemos pela primeira vez no país um canhão de elétrons de baixas energias, produzindo feixes de elétrons monocromatizados. O canhão foi cuidadosamente caracterizado em termos da intensidade do feixe eletrônico incidente e sua monocromatização, atingindo-se valores de energia de 0,105 eV e intensidades de até 280 nA para feixes de 170 eV. / In a variety of spectroscopic techniques of electron impact on gaseous samples, it is essential to use electron beams of low energy focused, collimated and monochromatized. The electron beam intensity should be such that it is possible to perform data acquisition in minimal period time, with good statistics. The requirement of electron beam monochromatization ensures to get as much information of a spectrum. It is in the low-energy electron incident that important processes occur, such as distortions in the electron cloud of the target, polarization effects, exchange effects and electron capture. However, it is precisely in this energy range where the experiments are more difficult to run due to the high sensitivity of the incident and scattered electron beam. In this work, we developed first in this country an electron gun for low energies, producing monochromatized electron beams. The electron gun has been carefully characterized in terms of intensity of the incident electron beam and its capacity of monochromatization, reaching values of energy of 0.105 eV and beam intensities up to 280 nA of 170 eV.

There is limited research using small-scale simulation in applied behavior analysis. We used small-scale simulation to train firearm safety skills to 3 to 5-years-old children and assessed whether the skills generalized to the natural environment through in situ assessment. Three participants completed the training and all participants learned the safety skills from simulation training. Two of the participants acquired the safety skills after the first simulation training and the third participant required one booster training before demonstrating the safety skills in the natural environment.

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The presented diploma thesis informs about the origin, history, and benefits of technical snowmaking. It introduces what snow equipment consists of and what processes artificial snow is produced. It also shows the price of tons of snow produced from individual commercially available equipment. In the experimental part, the work deals with the calculation of droplet freezing for various input parameters of water, environment, and equipment. A sample calculation was performed for a falling water droplet from a snow lances. The droplet of discharged water was 0.3 mm in size and had a temperature of 2 ° C. The temperature of the environment was chosen to be -10 ° C. Furthermore, the trajectory of the droplet from a snow gun was determined. In the design, a specific snow pole was designed for the specified parameters, including the speed of the environment. The results were then compared with snow poles available on the market.

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Diploma thesis deals with problems about deep drilling of aeronautical part made of aluminum alloy EN AW 7075 T7351. This work is focused on the material properties component and current aluminum alloys processing. Further it contains a part delicated to various kinds of technologies of deep drilling, primarily is focused to gun drilling. Describes a tool, technology and conditions in gun drilling of deep holes with focused to analysis of the forces. Then it compares contemporary manufacturing technology of part drilling in cooperation and proposes an innovative technology of manufacturing. This project is accomplished with technical-economical evaluation.

This thesis deals with the influence of changes in cutting parameters and tool geometry on residual stress inside the material. I examine the influence by deep drilling. Changing the cutting parameters concerns the alteration of the tool feed and the pressure of the coolant during the process. The influence of tool geometry is studied by using two different single edge cannon drills. The research was realized in cooperation with Bosch Diesel Ltd. The theoretical part includes a description of the injection system, in which a high-pressure container is contained. The high-pressure container was used to evaluate the influence of the cutting parameters and tool geometry on residual stress. Furthermore, the theoretical part deals with the deep drilling technology used and the theory of residual stresses. The practical part shows the measurement parameters and the corresponding results. In the conclusion of this thesis, a technical-economic evaluation of the measurement is conducted.

In der vorliegenden Arbeit wird die Optimierung des REXEBIS-Ladungsbrüters an der ISOLDE präsentiert. Die REXEBIS in der aktuellen Konfiguration erzeugt eine Elektronenstromdichte in der Fallenregion bei 2 T von 200A/cm² und wird bis zu ihren physikalischen Grenzen optimiert. Um diese Begrenzung zu überwinden wurde eine neue Elektronenkanone, die HEC²-Elektronenkanone, in Kooperation mit BNL konstruiert und an der TestEBIS in Betrieb genommen. Diese Elektronenkanone verspricht eine Elektronenstromdichte von mehr als 10 kA/cm² bei 5T, welche die Ladungsbrütungszeit entscheidend verkürzt. In dieser Dissertation werden neuartige Simulationstechniken vorgestellt, welche die Inbetriebnahme durch Untersuchung der Mechaniken von auftretenden Verlustströmen beschreiben. Dazu wird der Elektronenkollektor der TestEBIS nach Kompatibilität bezüglich der HEC²-Elektronenkanone, die nahe derer Designwerte betrieben wird, evaluiert. Die gewonnenen Erfahrungen von der Inbetriebnahme der HEC²-Elektronenkanone und den etablierten, numerischen Techniken führen zur Entwicklung einer kleineren hochkomprimierenden Elektronenkanone für medizinische Anwedungen, die MEDeGUN. Diese Elektronenkanone sollte einen qualitativ hochwertigen Elektronenstrahl generieren, welcher eine Elektronenstromdichte von 7.5 kA/cm² in der Fallenregion bei 5 T axialen Magnetfeld erzeugt. Eine EBIS/T, ausgestattet mit einer MEDeGUN, wird bezüglich Pulsfrequenz und bereitgestellten Ionenstrom zu Hochfrequenz-Therapiezentren der zweiten Generation kompatibel sein. / In this thesis the optimization of the REXEBIS charge breeder at the ISOLDE facility is presented. REXEBIS in its current state provides a current density of 200A/cm² inside the trapping region at 2 T and will be optimized to the physical limit of its design. To overcome this limit a new electron gun, the HEC² gun, was designed in collaboration with the BNL and is in commission at TestEBIS. This electron gun promises a current density of >10 kA/cm², which decreases the charge breeding time significantly. This thesis presents novel simulation techniques supporting the commissioning phase by explaining the sources of occurring loss current and, in addition, evaluate the currently installed collector for compatibility with the HEC² gun operating at its design limit. The experience gained from the commission of the HEC2 gun and the established numerical techniques lead to the development of a smaller high-compression electron gun for medical purposes, the MEDeGUN. This electron gun should provide a high-quality beam, which generates a calculated current density of 7.5 kA/cm² inside the trapping region immersed in a 5 T axial magnetic field. An EBIS/T equipped with a MEDeGUN will be compatible regarding the pulse frequency and deliver the mandatory ion current required for second generation therapy centers.

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