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The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance. [ABSTRACT FROM AUTHOR]

The main difficulty in forecasting traffic volumes along a rural bypass is identifying the external traffic, both traffic entering the town from outside and traffic continuing through the town to an ultimate destination. Three methods exist for determining the percentage of external traffic destined for town, external-internal, or through town, external-external: A comprehensive origin-destination study, cordon line origin-destination study, or a regression equation. The objective of this paper is to examine the possibility of using different techniques, based on spatial economic models to determine the traffic percentages. This project will use three different models to determine the activity base for the city of Waverly, Iowa, and compare the models with the results given by the regression equation and a cordon line origin-destination study performed in the 1970s. This paper demonstrates that Huff's probability contour model performs well lot the case study and recommends that this model be used in the future to provide estimates that incorporate a community's economic relationship to neighboring towns.

Preparingnew ternary compounds via traditional high temperaturesynthesis techniques is essentially limited to ternary compounds thatare thermodynamically more stable than any mixture of binary compoundsbecause binary compounds typically form as reaction intermediates.By using a precursor having elemental layers thinner than a criticalthickness, it is possible to decrease diffusion times such that thelayers interdiffuse before nucleation of binary compounds occurs atreacting interfaces. To nucleate the ternary compounds CuInSe2and CuCr2Se4directly from amorphousreaction intermediates, however, it is shown to be necessary to usethe order of the elemental layers to control of the order of mixingof the elemental layers. Controlling layer thickness and layer sequenceis a general strategy for avoiding binary compounds as reaction intermediates,providing a general approach to preparing kinetically stable ternarycompounds. [ABSTRACT FROM AUTHOR]

The structures of three new misfit layer compounds, [(PbSe)0.99]1[WSe2]1, [(PbSe)1.00]1[MoSe2]1, and [(SnSe)1.03]1[MoSe2]1, prepared as thin films from designed elementally modulated reactant precursors, have been investigated by synchrotron X-ray diffraction and scanning transmission electron microscopy. This is the second report of a misfit layer compound based on tin selenide and the first structure determinations of tungsten- and molybdenum-containing misfit layer compounds. The compounds have mismatches in both the a- and b-axis (in-plane) lattice parameters of the component structural units, which result in misfit parameters, δ, both greater and smaller than zero. Pole figures of hk0-type reflections indicate that c-axis-oriented (basal plane) dichalcogenide-structured units are randomly oriented within the a- b plane. The widths of diffraction peaks of type hk0, 00 l, and hkl ( h, k ≠ 0; l ≠ 0) indicate coherence lengths of approximately (6 to 7) nm within the a- b plane, the full thickness of the film along the c-axis, and (1 to 2) nm in mixed-index directions, respectively, consistent with random rotational disorder between the constituents, commonly termed turbostratic disorder in the clay literature. The intensities of 00 l- and hk0-type diffraction peaks were modeled to determine the structure of atomic planes along the c axis and the projection of the constituent structures onto the a- b plane, respectively. [ABSTRACT FROM AUTHOR]

Recently there has been interest in developing imaging contrast media for magnetic resonance imaging (MRI) that contain biologically rare, magnetically active nuclei such as fluorine. In principle, fluorinated contrast agents can be used to generate highly selective 19F magnetic resonance images that can be superimposed over complimentary 1H magnetic resonance images to provide an anatomical context for the fluorinated contrast agent. Additionally, nanoparticles can be made to target various pathological sites via active and passive targeting mechanisms. In this study, fluorinated nanoparticles were produced using a free radical polymerization of vinyl formamide monomers with two different fluorinated monomers. The nanoparticles showed a clear, single 19F-NMR signal. Additionally, surface amide groups were hydrolyzed to primary amines to yield additional surface reactivity. Fluorinated nanoparticles produced using a free-radial polymerization method yield a new nanoparticle for 19F-MRI applications with potential for facile functionalization. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Abstract: Atomized silver spheres (≤53μm diameter) were coated with a 1μm thick layer of (La0.6Sr0.4)0.98Co0.2Fe0.8O3−δ via a mechanofusion dry processing method. The material was successfully utilized as an SOFC cathode on anode-supported YSZ electrolytes at 700°C, producing >500mWcm−2 (at 0.7V) and exhibiting relatively stable performance (∼3% power degradation per 1000h at 0.7V) during >2000h of operation. [Copyright &y& Elsevier]

(La0.8Sr0.2)0.98Fe0.98Cu0.02O3-δ can be sintered directly onto YSZ (without the need for a protective ceria interlayer). Though subject to an extended ‘burn-in’ period (∼200 h), anode-supported YSZ cells using the Cu-doped LSF achieve power densities ranging from 1.3 to 1.7 W/cm2 at 750°C and 0.7 V. These cells have also demonstrated 500 h of stable performance. The results are somewhat surprising given that XRD indicates an interaction between (La0.8Sr0.2)0.98Fe0.98-Cu0.02O3-δ and YSZ resulting in the formation of strontium zirconate and/or monoclinic zirconia. The amount and type of reaction product was found to be dependent on cathode and electrolyte powder precalcination temperatures. [ABSTRACT FROM AUTHOR]