Polarisation of the 61S0 - 61P1 and 61S0 - 63P1 lines of mercury, excited by electron impact

The polarisation of the 61S0 – 61P1 (1850 A) and the 61S0 – 63P1 (2537 A) lines of mercury, excited by ow energy electron impact, have been measured. In both cases, the emitted radiation was observed in a direction perpendicular to the electron beam. In the first instance, the polarisation of the 2537 A line was measured with an energy resolution of 300 meV, in an experiment where the mercury was in the form of a vapour. The results from this gave a first indication that resonances in the excitation of the line are responsible for departures of the polarisation from the theory of McConnell and Moiseiwitsch. A crossed-beam apparatus was assembled, and the polarisation of the 1850 A line was measured, again under low resolution. Agreement with the theory in this case is reasonable, apart from in the region with a few eV of threshold, where the measured polarisation is rather lower than that predicted. To examine more carefully the resonances observed in the 2537 A line, an electron monochromator was built, and the polarisation of the line was measured under high resolution. Data are presented with an energy resolution of 140 meV and 100 meV. A total of six features are observed, of which resonances at 4.92 and 5.50 eV are particularly well marked. The observed polarisation of the resonance at 4.92 eV appears to be in agreement with the hypothesis that 4P3/2 negative ion state of mercury is being formed at that energy

Food-induced Emotional Resonance Improves Emotion Recognition

The effect of food substances on emotional states has been widely investigated, showing, for example, that eating chocolate is able to reduce negative mood. Here, for the first time, we have shown that the consumption of specific food substances is not only able to induce particular emotional states, but more importantly, to facilitate recognition of corresponding emotional facial expressions in others. Participants were asked to perform an emotion recognition task before and after eating either a piece of chocolate or a small amount of fish sauce – which we expected to induce happiness or disgust, respectively. Our results showed that being in a specific emotional state improves recognition of the corresponding emotional facial expression. Indeed, eating chocolate improved recognition of happy faces, while disgusted expressions were more readily recognized after eating fish sauce. In line with the embodied account of emotion understanding, we suggest that people are better at inferring the emotional state of others when their own emotional state resonates with the observed one

Abiotic ammonium formation in the presence of Ni-Fe metals and alloys and its implications for the Hadean nitrogen cycle

Experiments with dinitrogen-, nitrite-, nitrate-containing solutions were conducted without headspace in Ti reactors (200°C), borosilicate septum bottles (70°C) and HDPE tubes (22°C) in the presence of Fe and Ni metal, awaruite (Ni80Fe20) and tetrataenite (Ni50Fe50). In general, metals used in this investigation were more reactive than alloys toward all investigated nitrogen species. Nitrite and nitrate were converted to ammonium more rapidly than dinitrogen, and the reduction process had a strong temperature dependence. We concluded from our experimental observations that Hadean submarine hydrothermal systems could have supplied significant quantities of ammonium for reactions that are generally associated with prebiotic synthesis, especially in localized environments. Several natural meteorites (octahedrites) were found to contain up to 22 ppm Ntot. While the oxidation state of N in the octahedrites was not determined, XPS analysis of metals and alloys used in the study shows that N is likely present as nitride (N3-). This observation may have implications toward the Hadean environment, since, terrestrial (e.g., oceanic) ammonium production may have been supplemented by reduced nitrogen delivered by metal-rich meteorites. This notion is based on the fact that nitrogen dissolves into metallic melts

The geochemistry of Middle Jurassic dykes associated with the Straumsvola-Tvora alkaline plutons, Dronning Maud Land, Antarctica and their association with the Karoo large igneous province

Jurassic dykes of western Dronning Maud Land (Antarctica) form a minor component of the Karoo large igneous province. An extensive local dyke swarm intrudes Neoproterozoic gneisses and Jurassic syenite plutons on the margins of the Jutulstraumen palaeo rift in the Svedrupfjella region. The dykes were intruded in three distinct episodes (~204, ~176 and ~170 Ma). The 204 Ma dykes are overwhelmingly low-Ti, olivine tholeiites including some primitive (picritic) compositions (MgO >12 wt.%; Fe2O3 >12 wt.%; Cr >1000 ppm; Ni >600 ppm). This 204 Ma event precedes the main Karoo volcanic event by ~25 Ma, so any correlations to the wider province are difficult to make. However, it may record the earliest phase of rift activity along the Jutulstraumen. The 176 Ma dyke event is more intimately associated with the two syenite plutons. The dykes are alkaline (basanite/tephrite) and were small-degree melts from an enriched, locally derived source and underwent at least some degree of interaction with a syenitic contaminant. This ~176 Ma dyke event is widespread elsewhere in the Karoo (southern Africa and Dronning Maud Land). Later-stage (170 Ma) felsic (phonolite-comendite) dykes intrude the 176 Ma basanite-tephrite suite and represent the last phase of magmatic activity in the region

Determination by ICP-MS, of background and BBR 3464 induced levels of platinum bound to DNA isolated from blood cells: A comparison of the sensitivity of the Perkin Elmer Sciex Elan 6000 and the ThermoFinnigan Neptune Instruments.

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RCCC calculations for electron scattering on quasi-two electron targets

We report on the recent extension of the RCCC method to accommodate electron scattering from quasi-two electron targets. We present results for electron scattering from mercury (Z = 80) which serves as a testing ground for relativistic theories due to its high atomic number. Furthermore electron-mercury scattering plays an important practical role in the physics of fluorescent and high intensity discharge lamps