Palladium-catalyzed three-component transformation of homoallenols: a regio- and stereoselective route to 1,5-amino alcohols

A palladium-catalyzed three-component transformation of enantioenriched homoallenols with aryl halides and amines has been developed to selectively afford (Z)-configured 1,5-amino alcohols in good-to-excellent yields without any epimerization.     

Bacteria-based AND logic gate: a decision-making and self-powered biosensor

We developed a bacteria-based AND logic gate using a Pseudomonas aeruginosa lasI/rhlI double mutant with two quorum-sensing signaling molecules as the input signals. We showed a distinct electrical output signal, despite the complexity and continuous regulation of metabolic reactions of living cells.     

A facile surfactant critical micelle concentration determination

Liquid surface curvature variations in microplate wells due to different liquid surface tension cause significant signal change in spectroscopic measurement using a plate reader with a vertical detecting light beam. The signals have been quantitated and used to develop a method for facile surfactant critical micelle concentration determination.     

Synthesis of tungsten carbide nanopowder via submerged discharge method

Tungsten carbide nanopowder was prepared via pulsed discharge of bulk tungsten and graphite rods immersed in pure ethanol. The effect of discharge parameters on the characteristics of final products was investigated. Structural and morphological characterization of nanopowder was performed by means of X-ray diffraction analysis and transmission electron microscopy. In order to determine the feasibility of using synthesized material as an electrocatalyst, tungsten carbide nanopowder was tested for hydrogen evolution. A correlation was found between morphology of nanoparticles, their phase composition and electrocatalytic activity.     

1H Nmr stuctural analysis of N3′-dialkylaminoethyl derivatives from azabicyclospirohydantoins

Based on the data from ¹H nmr spectra, the structure and spatial conformation of the N₃′-β-dimethyl and diethylaminoethyl derivatives from 3-alkyl-3-azabicyclo[3.2.1]octane-8-spiro-5′-hydantoins and 3-alkyl-3-azabicyclo[3.3.1]nonane-9-spiro-5′-hydantoins are established. The monosubstitution on the imide nitrogen atom has also been confirmed.     

Imaging nonequilibrium atomic vibrations with x-ray diffuse scattering

We use picosecond x-ray diffuse scattering to image the nonequilibrium vibrations in the lattice following ultrafast laser excitation. We present images of nonequilibrium phonons in InP and InSb throughout the Brillouin zone which remain out of equilibrium up to nanoseconds. The results are analyzed using a Born model that helps identify the phonon branches contributing to the observed features in the time-resolved diffuse scattering. In InP this analysis shows a delayed increase in the transverse-acoustic (TA) phonon population along high-symmetry directions accompanied by a decrease in the longitudinal-acoustic phonons. In InSb the increase in TA phonon population is less directional.     

Symmetry-breaking substitutions of [Re(CN)8]3- into the centered, face-capped octahedral clusters (CH3OH)24M9M'6(CN)48 (M = Mn, Co; M = Mo, W)

The diamagnetic complex [Re(CN)8]3- is shown to react with Mn2+ ions in methanol to generate the centered, face-capped octahedral cluster (CH3OH)24Mn9Re6(CN)48, which is structurally analogous to (CH3OH)24Mn9Mo6(CN)48. Related reactions involving stoichiometric mixtures of octacyanometalate complexes generate the substituted species (CH3OH)24Mn9Mo5Re(CN)48, (CH3OH)24Co9Mo5Re(CN)48, (CH3OH)24Mn9Mo3Re3(CN)48, (CH3OH)24Mn9W5Re(CN)48 and (CH3OH)24Co9W5Re(CN)48, in which the O(h) symmetry of the cluster core is broken. Reassessment of the magnetic properties of the Mn9Mo6(CN)48 cluster confirm that it possesses a ground state spin of S = 39/2, but does not exhibit single-molecule-magnet behavior. Lowering the symmetry of the molecule by substitutions of ReV at one or three of the MoV sites does not lead to an overall increase in the magnetic anisotropy, as probed by ac magnetic susceptibility measurements. A similar result occurs for the other substituted species, with the important exception of the new single-molecule magnet (CH3OH)24Co9W5Re(CN)48, for which the spin reversal barrier is significantly reduced relative to that observed previously in (CH3OH)24Co9W6(CN)48.