Sodium Atoms
Mostrando 1-12 de 53 artigos, teses e dissertações.
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1. Photoassociative ionization in situations with low dimensions / Investigação do processo de foto-ionização associativa em situações com baixa dimensão
Photoassociative ionization (PAI) in a cold sample of sodium atoms was the main subject of our studies as a way to understand the effects of repulsive states and collision dimensions. Two-color PAI experiment were preformed in a magneto-optical trap (MOT) trough the addition of a probe laser beam, the intensity, polarization and frequency of that probe laser
Publicado em: 2009
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2. Simulataneous temperature measurements of the upper mesosphere obtained lidar and airglow in the Brazilian low latitude sector / Medidas simultâneas de temperatura na mesosfera superior através de radar de laser e luminescência atmosférica em baixas latitudes no setor brasileiro
We present temperature measurements of the upper mesosphere obtained by lidar and airglow in the low latitude Brazilian sector over a period of two years. In the 80-110 km region, free sodium atoms are abundant enough to allow probing of the Doppler broadened hyperfine structure of the D2 resonance transition by ground-based lidar. The lidar technique consis
Publicado em: 2009
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3. Otimização da metodologia de determinação de molibdênio em solos e plantas por voltametria de onda quadrada com redissolução catódica adsortiva / Optimization of the molybdenum determination in soils and plant methodology by cathodic adsorptive stripping square- wave voltammetry
Molybdenum is an element essential to life that can be found practically in the whole biosphere. It is present in the nitrase enzyme cofactor and is responsible for the reduction of the N2 molecule and its fixation in the terrestrial crust. In other enzymes, molybdenum acts in reactions of transference of atoms of oxygen to a lot of sub-stratums. Molybdenum
Publicado em: 2008
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4. QuÃmica com quarks
Some properties of quark chemistry are obtained by performing accurate ab initio Hartree-Fock calculations on fractionally nuclear charged atoms and molecules formed by these atoms. Ground and first excited states of sodium, lithium, beryllium and magnesium atoms with quarks attached to the nucleus are obtained. It is suggested that the electronic transition
Publicado em: 2007
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5. Fotoionização de atomos relativisticos / Photoionization of relativistic atoms
In this work we present photoionization results for the valence s-electrons of Sodium, Potassium, Rubidium and Cesium atoms including relativistic effects. In our calculations we consider the photoionization of a non-polarized atom by linearly polarized light, using half occupation transition states, within the electric dipole approximation and the Local Den
Publicado em: 2007
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6. Obtenção da degenerescência quântica em sódio aprisionado / Achievement of quantum degeneracy in trapped sodium
Usando a técnica de resfriamento evaporativo para átomos comprimidos numa armadilha magnética tipo QUIC, implementamos experimentos para observar Condensação de Bose-Einstein de átomos de sódio. Nessa armadilha magnética temos átomos advindos de uma armadilha magneto-óptica, a qual é carregada por um feixe desacelerado como etapa de pré-resfriame
Publicado em: 2004
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7. Redução de amidas por boranos
Despite the fact that boranes are frequently used in amide reductions, the reaction mechanisms of the involved are note well known. This work presents the results of a bibliographic search on probable amide reduction mechanisms and an analysis of the existing literature. Steric and electronic effects were considered in light of reactivity since it could be c
Química Nova. Publicado em: 2002-05
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8. Experimental development to produce and study quantum gases: Bose-Einstein condensation / Desenvolvimento experimental para produção e estudo de gases quânticos: condensação de Bose-Einstein
We present here all the experimental development obtained in São Carlos to produce and study quantum degenerate gases, aiming specially the realization of Bose-Einstein Condensation (BEC) in sodium (Na-23) atoms. In order to do that we designed, built and completely integrated a complex experimental setup which conjugates most of the techniques developed al
Publicado em: 2002
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9. Studies on Optical Shielding of Cold Collisions / Estudo de Blindagem Óptica em Colisões Frias
In this work, we showed that is possible to suppress most of the inelastic processes that may cause losses of atoms in a magneto-optical trap. Our results reveal that the process of optical shielding (demonstrated by our group, for the first time to photoassociative ionization - Phys. Rev. Lett. 73, 1911 (1994)) is much more general than it was supposed. Eve
Publicado em: 1998
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10. Distribution of the marking with nitrogen 15 of protéicas fractions of beans-common (PHASEOLUS VULGARIS, L.) e isotópica dilution in the digestibilidade process in vitro. / Distribuição da marcação com nitrogenio 15 de frações proteicas de feijão-comum (Phaseolus vulgars L.) e diluição isotopica no processo de digestibilidade in vitro.
The aim of the present work was to verify if the isotope labelling with nitrogen 15 (15N) obtained in whole lyophilized beans, which had been labelled isotopically with 1.385% of 15N atoms of the total, was the same in the protein and protein fractions extracted from the beans. The aim was also to verify isotopic dilution of 15N, which occurs during in vitro
Publicado em: 1998
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11. Caracterização de uma armadilha magneto-optica para átomos de sódio em célula de vapor. / Characterization of a magneto-optical trap for sodium atoms in vapor cell.
Among the various atomic motion control techniques using radiation pressure magneto-optic trapping has been looked at with great enthusiasm because it produces samples of cold atoms (temperatures about μK), with high densities and confined in small regions of space. Due to these motivations the efforts for developing and characterizing these atoms traps
Publicado em: 1994
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12. Construção de um sistema experimental para desaceleração de átomos. / Construction of an experimental system for stopping atoms.
This work presents the development and test of an experimental set-up which allows to produce a very strong slow motion atomic beam. We discuss the calculation and construction of the solenoid to compensate the Doppler effect arising during the deceleration process, vacuum chambers, the oven which produces the atomic beam and the optical system used. We have
Publicado em: 1991