154 research outputs found

    Quantification of UV stimulated ice chemistry: CO and CO2

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    Recent laboratory experiments are presented that show that during photolysis of the pure ices there is evidence of the interconversion of CO to CO2 and CO2 to CO using Lyman alpha (1216A) radiation. In addition, there is a substantial amount of another substance being produced. This substance is evident by its infrared absorption peak at 2235 cm(-1). It is believed that this new peak is due to carbon suboxide, C3O2. CO and CO2 have already been detected in comets, and C3O2 has been suggested as a cometary from radiation of CO. Comparisons are made between our results at 1215A and proton radiation experiments and radiation at other wavelengths. The suggestion is that the processing of ices is energy dependent, i.e., dependent on the type of radiation. Several difficult problems have to be solved before these radiation conversions can be quantified. The steps that we are taking to quantify the kinetics are discussed

    On the addition of degrees of freedom to force-balanced linkages

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    The design of shaking-force balanced linkages can be approached by deriving these linkages from balanced linkage architectures. When desired, a possible step is to add degrees-of-freedom (dof), for instance by substituting a link with a n-dof equivalent linkage for which the balanced design of the other links is not affected. This paper shows how the coupler link of a shaking-force balanced 4R four-bar linkage, applied as a 5R five-bar linkage, can be substituted with an equivalent 2-dof pantograph

    High temperature phase transition in the coupled atom-light system in the presence of optical collisions

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    The problem of photonic phase transition for the system of a two-level atomic ensemble interacting with a quantized single-mode electromagnetic field in the presence of optical collisions (OC) is considered. We have shown that for large and negative atom-field detuning a photonic field exhibits high temperature second order phase transition to superradiant state under thermalization condition for coupled atom-light states. Such a transition can be connected with superfluid (coherent) properties of photon-like low branch (LB) polaritons. We discuss the application of metallic cylindrical waveguide for observing predicted effects.Comment: 8 pages, 2 figure
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