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With ICT Standards playing a key role in support of research and development in many disciplines, the European Commission Institute for Energy and Transport is keen to promote the development and adoption of ICT Standards for engineering data. In this respect, its MatDB Online facility is a Standards-based system for preserving, managing, and exchanging engineering materials test data. While MatDB Online has evolved over more than 30 years to incorporate the latest innovations in data preservation and exchange, such as XML-based data transfer and data citation using digital object identifiers, it continues to rely on a robust data model developed more than 30 years ago through the joint efforts of the National Research Institute for Metals (the predecessor to NIMS, the National Institute for Materials Science), the European Commission Joint Research Centre, and the National Institute of Standards and Technology. While this data model has endured over many years, there is no corresponding Standard. Similarly, related efforts by the engineering materials community to deliver a Standard representation for engineering materials, such as MatML, have failed to be ratified. In consequence of the continued absence of a Standard representation for engineering materials data, there is no common mechanism for preserving and exchanging materials data and no formal means of maintaining a data model to support advances in materials technology, such as the emergence of nanomaterials. It is for these reasons that the European Commission Institute for Energy and Transport is supporting SERES, a CEN Workshop on Standards for Electronic Reporting in the Engineering Sector. As one of more than thirty organisations supporting the SERES Workshop, the Institute for Energy and Transport will make the MatDB XML schema available as one of several resources that will be taken into consideration when the prenormative Standard for representing engineering materials data is formulated. With the participation of the Institute for Energy and Transport in the SERES Workshop taking place in parallel with a related project with Oak Ridge National Laboratory, there is good reason to expect that a Standard representation for engineering materials, which has so far eluded the materials community, will be realised. This paper describes MatDB support for engineering materials Standards and related innovative features. [ABSTRACT FROM AUTHOR]

Abstract: Applying in situ surface X-ray diffraction (SXRD) together with on-line mass spectrometry during the CO oxidation over Ru(0001) allows a direct comparison of the reactivity of the non-oxidic state with that of the RuO2(110) covered surface. This comparison reveals that the RuO2(110) surface is a catalytically active phase at least as active as the non-oxidic phase. At high CO and O2 pressures of 200mbar and temperatures above 550K, the CO oxidation reaction does not proceed isothermally on the RuO2(110) surface. The released reaction heat leads rather to an increase of the sample temperature of up to 130K accompanied by a self-acceleration of the CO oxidation reaction. [Copyright &y& Elsevier]

We have reinvestigated the bond geometry of the surface by means of low-energy electron diffraction using a much larger experimental data set than that previously used. The surface consists of a lattice of atoms which replaces the topmost atoms, and forces the remaining atoms to form trimers. The bond length turned out to be 3.47±0.12 Å. The atoms are laterally displaced from the bulk positions of the atoms which they have replaced by 0.53 Å resulting in a bond length of 2.36±0.17 Å. The missing top layer and the formation of trimers lead to strong distortions in deeper layers, most notably a buckling in the third and fourth layer with a magnitude of about 0.35 Å and 0.2 Å, respectively. Applying the concept of 'split positions', the low Debye temperature of has been interpreted as being caused by strong in-plane (either static or dynamic) movements of the Ag atoms perpendicular to the bonding. [ABSTRACT FROM AUTHOR]

The structural properties of the ordered overlayers of , and on (0001) are summarized. The major result is that the adsorption site depends on the coverage while the hard-sphere radii of the alkali-metal atoms do not change (if corrected for different numbers of coordination). This comparison also emphasizes the singular behavior of for which adsorption takes place over single atoms at a coverage of 0.25. While on other close-packed substrate surfaces potassium and rubidium occupy ontop positions at low temperatures, this has not been found with (0001). This finding points towards the important role of the substrate. For the ontop adsorption to be favored, an inward displacement of the substrate atoms directly underneath the alkali-metal atoms by a substantial amount is necessary which results in the formation of a quasisevenfold-coordinated bond geometry in connection with a reduction of the dipole-dipole repulsion. The stiffness of the substrate determines the energy cost for this local reconstruction, and consequently ontop adsorption on the hard (0001) substrate has only been observed for the biggest alkali metal where the energy difference between various adsorption sites [on the unrelaxed (0001) surface] is assumed to be small. In order to force potassium to reside in the ontop position, the (0001) surface has to be 'softened' which task was accomplished by adding CO molecules to the K-(2×2) overlayer. [ABSTRACT FROM AUTHOR]

Samenvatting. De afstandsmethode voor het schatten van een dichtheid, bijv. het stamtal per ha in bossen, werd voorgesteld en uitgewerkt door F. E. Essed [1], Men zou deze ook kunnen interpreteren ah een 'wachttijdmethode' ter bepaling van de frequentie per tijdseenheid van een (in de tijd) poisson verdeelde gebeurtenis als het binnenkomen van gesprekken op een telefooncentrale. In dit artikel wordt de methode verder ontwikkeld, waarbij een toepassing, nl. het tellen van slakken (van de soort Galba trunculata, gastheer van de leverbot) in greppels -dit als onderdeel van een onderzoek naar de biologie van de leverbot -, nader wordt beschreven (par. 2). Na definities (par 1.0) (in bosbouwkundige termen) van achtereenvolgens: een bos, een toevallig bos, een (homogeen) poisson-bos een locaalpoisson-bos, worden enige nieuwe schatters gedefinieerd ((1) en (2) in par. 1.1.), en hun eigenschappen voor een homogeen poisson-bos besproken. Voor een locaal poisson-bos wordt een afzonderlijke schatter besproken (par. 1.2). In par. 1.3 wordt een homogeniteits-toets besproken, alsook een dichtheidsschatter, die al naar de omstandigheden een telling van bomen of een afstandsmeting is. In par. 1 worden de statistische technieken met enkele hulptabellen besproken. Par. 2 beschrijft het ontwikkelen van een veldmethode voor het tellen van slakken bij het leverbotonderzoek. Par. 3 geeft de wiskundige achtergrond voor de methoden beschreven in par. 1. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the structure of ruthenium oxide and the mechanism for catalytic carbon monoxide oxidation on its surface. How structural analysis was performed; Verification on the responsibility of coordinatively unsaturated metal ions for the high reactivity of the ruthenium oxide structure; Conclusion.