159 research outputs found
INTERMOLECULAR POTENTIAL OF EXCITED ATOMS AND MOLECULES FROM MATRIX SHIFTS.
No full text J.-Y. Roncin, J. Mol. Spectry, 26, 105 (1968). J.-Y. Roncin, N. Damany and B. Vodar, Chem. Phys. Letters, March 1969.Author Institution: Laboratoire des Hautes, Pressions, C.N.R.S., Bellevue France and National Research Council of Canada Division of Pure PhysicsThe experimental shifts and broadening of far u.v. transitions of trapped species have so far permitted only qualitative conclusions concerning the dimensions of the excited In particular the matrix isolation technique has strikingly shown the profound difference in behavior of trapped molecules according to the nature of the transition; valence transitions are little affected whereas Rydberg transitions are strongly Enough experimental data are now available to attempt a quantitative estimation of the dimension of some excited states on the basis of a simple Lennard-Jones intermolecular potential . The values of and , computed for some excited states of Xe, Kr, Hg, CO, NO and , are given below: [FIGURE] During the year 1969, J.-Y. Roncin has been a Postdoctoral Fellow at the Division of Pure Physics, National Research Council of Canada, Ottawa, Canada
Dispersion insensitive, high-speed optical clock recovery based on a mode-locked laser diode
No full textAn investigation into the effects of varying levels of chromatic dispersion on a mode- locked laser diode optical clock recovery process is presented. Results demonstrate that this technique is invariant to input dispersion varying between +75 ps/nm
Validation of a simple aerodynamic model capable to predict the interaction effects occuring between two generic wind propulsion systems
No full textIn recent years wind-assisted propulsion for commercial ships has gained an increasing interest as valuable alternative to reduce fuel pollutant emissions. However, the development of feasible and commercially viable wind propulsion systems to partially (or fully) propel a ship is nowadays hindered by the difficulties of modelling the complicated aerodynamic and hydrodynamic aspects involved. From an aerodynamic point of view, it appears that one of the main challenges of predicting the performance of a wind-assisted ship, is to properly evaluate the interaction effects that occur between the various wind propulsion systems mounted on the deck of the ship. This research deals with the validation of a simple and quick-to-use aerodynamic model that is capable of evaluating such effects, i.e. upwash, downwash and wake, occurring between two generic propulsion systems placed at any given relative position on the ship's deck. The wind propulsion systems might assume any given angle of attack; the flow can be attached as well as separated. Such aerodynamic model, that was first presented in [1], consists of the horseshoe vortex method modified with semi-empirical formulas to take into account the effects of viscosity. First, the results provided by the aerodynamic model were compared with results obtained by using more sophisticated tools, i.e. a CFD body force model and RANS CFD. Then, experimental validation was carried out by means of dedicated wind-tunnel tests. It can be concluded that, despite the simplicity of the aerodynamic model employed, it proved to give reasonable results when compared to more sophisticated tools and to experimental data. REFERENCES [1] K. Roncin and J.M. Kobus, “Dynamic simulation of two sailing boats in match racing”, Sports Engineering , Vol. 7, pp. 139-152, (2004)
ULTRAVIOLET ABSORPTION SPECTRUM OF MERCURY IN Ne, Ar, Kr, AND Xe MATRICES
No full text J.-Y. Roncin and N. Damany-Astoin, Compt. Rend, 253, 835 (1961). b M. McCarty, Jr. and G. W. Robinson. J. Chem. Phys. 56, 723 (1959), and Mol. Phys. 3, 301 (1960).Author Institution: Inorganic Materials Research Division and Chemistry Department, University of CaliforniaThe absorption spectrum of mercury in Ne, Ar, Kr, and Xe matrices in the region from 2000 to has been studied as a function of temperature, deposition rate, and concentration. The fine structure of the main absorption, attributed to the transition, has been re-examined. The results are compared with those of other workers, and an apparently contradictory observation in the case of is discussed
HIGH RESOLUTION STUDY OF THE SYSTEM OF ISOTOPIC SPECTES OF CO
No full textAuthor Institution: Launay and Letzelter: Observatoire de Paris, D\'epartment d'Astrophysique Fondamentale (C.N.R.S. U.A. 812); Equipe de Spectroscopie (C.N.R.S. U.A. 171), Ecole des Mines; D\'epartement de Physique, Universit\'eA de ToursThe Vacuum Ultra-Violet Band Spectrum System of 12C160, 13C160, 12C180 and 13C180 have been extensively studied at High Resolution in both Absorption and Emission. In Absorption a band, observed in all isotopes, is shown to be with however anomalous vibrational spacing and rotational constants and a local perturbation. Some of the observed emission bands have not been reported before even at low resolution and none at high resolution. All of them exhibit sharp breaking off typical of predissociation of CO, giving directly an improved upper limit for the Dissociation Energy of the ground state of CO into C(3P)+O(3P)
The meaning of reconciliation and development in post-genocide Rwanda.
No full textWhen the characteristic of mass violence is primarily intrastate rather than interstate in nature, as was the case during the 1994 Rwandan genocide, geographical separation among conflicting groups is not always a viable solution. In such cases, reconciliation can present a way to recuperate and rebuild broken relationships amongst former adversaries. Reconciliation itself, however, is not a general concept or set of rules to be equally applied towards different groups or countries. This thesis is centered on a key question: what are the meanings of reconciliation and development in post-genocide Rwanda, and how are they related? To examine this relationship, three possible connections are conceptualized: social healing and community development, reparations and economic development, and shared views on history and political development. This research contends that in a post-conflict setting, development without reconciliation is an incomplete process. --P. i.The original print copy of this thesis may be available here: http://wizard.unbc.ca/record=b175496
High resolution emission spectra of H2 and D2 near 80 nm
No full textA few lines have been observed in the far ultraviolet emission spectrum of molecular hydrogen and deuterium. They are assigned to transitions from levels of the 3pπD 1Π u- state, lying above the dissociation limit into H(ls) + H(n = 2), near 84.5 nm, and, for some of them, above the first ionization limit near 80.4 nm, the lower state being X 1Σg+ (v" = 1). This is in fair agreement with measured predissociation and preionization yields. Accurate line position measurements lead to molecular constants in very good agreement with theoretical calculations.Quelques raies ont été observées dans le spectre d'émission ultraviolet lointain de l'hydrogène et du deutérium. Ces raies sont attribuées à des transitions partant de niveaux de l'état 3pπD 1Π u- situés au-delà de la limite de dissociation en H(ls) + H(n = 2) près de 84,5 nm et, pour certains, au-delà de la premiere limite d'ionisation près de 80,4 nm, l'état inférieur étant X 1 Σg+ (v" = 1). Les résultats sont en accord avec les mesures de taux de prédissociation et de préionisation. La mesure précise des positions de raies permet de déduire des constantes moléculaires en très bon accord avec les calculs théoriques
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