Cathode-supported micro-tubular SOFCs based on Nd1.95NiO4 + δ: Fabrication and characterisation of dip-coated electrolyte layers

Fabrication conditions to obtain dense electrolyte double layers on a porous micro-tubular cathode substrate were investigated. Porous tubes of a nickelate material, Nd_1.95NiO_4 + δ, were fabricated by cold-isostatic pressing (CIP) and sintering. Thin films of electrolyte powders Ce_0.9Gd_0.1O_1.95 (GDC) and Zr_0.89Sc_0.1Ce_0.01O_1.95 (SSZ) were applied by dip-coating in aqueous suspensions. Electrolyte powders had been attrition-milled to decrease their particle size and densification temperature. The quantity of polyacrylic acid (PAA) as dispersant was optimised by ζ-potential measurements. The densification behaviour was studied by dilatometry and SEM-imaging. A sintering temperature of 1250 °C was found to densify GDC whereas SSZ-layers remained slightly porous.     

Proficiency test on incurred and spiked pesticide residues in cereals

A proficiency test on incurred and spiked pesticide residues in wheat was organised in 2008. The test material was grown in 2007 and treated in the field with 14 pesticides formulations containing the active substances, alpha-cypermethrin, bifentrin, carbendazim, chlormequat, chlorpyrifos-methyl, difenconazole, epoxiconazole, glyphosate, iprodione, malathion, pirimicarb, prochloraz, spiroxamin and trifloxystrobin. After harvest, the test material was additionally spiked in the laboratory with three pesticides, that where the residues were too low, and axozystrobin. In total, 72 laboratories submitted results and z-scores were calculated for all laboratories and pesticides, except for glyphosate where only five laboratories submitted results and summed weighted z-scores were calculated for the laboratories with a sufficient scope. For several pesticides, the submitted results were strongly depending on the extraction procedure and consequently the assigned values were calculated based on part of the results. Acceptable z-scores were obtained by 56–97% of the participants.     

6‐Aza‐2′‐deoxy‐2′‐arabino­fluoro­uridine,a 2′‐deoxy­ribonucleoside with an N‐sugar conformation in the solid state and in solution

In the title compound, 2‐(2‐deoxy‐2‐fluoro‐β‐d ‐arabino­fur­anosyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione, C₈H₁₀FN₃O₅, the torsion angle of the N‐gly­cosylic bond is anti [χ = −125.37 (13)°]. The furan­ose moiety adopts the N‐type sugar pucker (³T₂), with P = 359.2° and τ_m = 31.4°. The conformation around the C4′—C5′ bond is antiperiplanar (trans), with a torsion angle γ of 177.00 (11)°. A network is formed via hydrogen bonds from the nucleobases to the sugar residues, as well as through hydrogen bonds between the sugar moieties.     

EPR Study of the Kinetics of the Formation of Radicals from Dibenzoyl Peroxide on Porous Glass

The kinetics of the formation of radicals from dibenzoyl peroxide supported on porous glass have been determined with EPR techniques over the temperature range of 25-100°C. Values of the activation energy of 18.5 and 25 kcal/mole have been observed for two differently prepared porous glass support materials.     

A Numerical Study of Characteristic Slow-Transient Behavior of a Compressible 2D Gas-Liquid Two-Fluid Model

The purpose of this paper is to gain some insight into the characteristic behavior of a general compressible two-fluid gas-liquid model in 2D by using numerical computations. Main focus is on mass transport phenomena. Relatively few numerical results in higher dimensions can be found in the literature for this two-fluid model, in particular, for cases where mass transport dynamics are essential. We focus on natural extensions to 2D of known 1D benchmark test cases, like water faucet and gas-liquid separation, previously employed by many researchers for the purpose of testing various numerical schemes. For the numerical investigations, the WIMF discretization method introduced in [SIAM J. Sci. Comput. 26 (2005), 1449] is applied, in combination with a standard dimensional splitting approach. Highly complicated flow patterns are observed reflecting the balance between acceleration forces, gravity, interfacial forces, and pressure gradients. An essential ingredient in these results is the appearance of single-phase regions in combination with mixture regions (dispersed flow). Solutions are calculated and shown from early times until a steady state is reached. Grid refinement studies are included to demonstrate that the obtained solutions are not grid-sensitive.     

Endofiniteness in stable homotopy theory

We study endofinite objects in a compactly generated triangulated category in terms of ideals in the category of compact objects. Our results apply in particular to the stable homotopy category. This leads, for example, to a new interpretation of stable splittings for classifying spaces of finite groups.

     

Evolution of Elastic T-stresses of Growing Mixed-Mode Cracks

Finite element simulations of growing mixed-mode central line-cracks (2-D case) and internal penny-shaped cracks (3-D case) have been performed to address the evolution of the elastic T-stresses acting at the crack-tip (the non-singular stress terms in the stress expansion formula at the crack-front). (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)