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Abstract.The structure of the magnetotail is investigated in a laboratory simulated magnetosphere. This study builds upon our previous investigation of the magnetotail [Birn et al., 1992], which was explored magnetotail through models and magnetic field measurements in the simulated magnetosphere. In this paper the magnetic field measurements are complemented by measurements of ion and electron fluxes, plasma temperature and high-resolution optical images. Plasma fluxes are measured with a double-sided Faraday cup that measures the ion and electron fluxes of counterstreaming plasma simultaneously in both directions. The overall magnetotail structure is examined with high-resolution imaging using a gated optical imager and applying digital enhancement to the magnetotail region. These images confirm the structures inferred earlier from the magnetic field measurements, a Y-type magnetic neutral line for northward interplanetary magnetic field, and the expected X-type structure for southward IMF.

Iron polypyridyl complexes have recently been reported to electrocatalytically reduce protons to hydrogen gas at-1.57 V vs. Fc + /Fc. A new iron catalyst with a nitrofunctionalized polypyridyl ligand has been synthesized and found to be active for proton reduction. Interestingly, catalysis occurs at-1.18 V vs. Fc + /Fc for the nitro-functionalized complex, resulting in an overpotential of 300 mV. Additionally, the complex is active with a turnover frequency of 550 s-1. Catalysis is also observed in the presence of water with a 12% enhancement in activity.

We report the synthesis and stereospecific solid-state photodecarbonylation of a hexasubstituted ketone featuring six distinct α-substituents. The photoproduct of the solid-state transformation features vicinal all-carbon quaternary stereocenters. While reactions carried out in bulk powders and aqueous crystalline suspensions were complicated by secondary photochemistry of the primary photoproduct, optimal conditions provided good yields and recyclable starting material. Subsequent transformations of the α-substituents having orthogonal chemical reactivity illustrate the potential of this transformation toward constructing complex architectures.