Effects of Dissimilar Metal Coupling, Potential Distribution, and Temper Condition on Galvanic Corrosion of 5086 Aluminum Alloy in Synthetic Seawater

The galvanic corrosion behavior of 5086 aluminum alloy in three tempers {Hll6, Hll7, H32) when coupled with more noble metals {1040 steel, naval brass, and Ti-150A titanium) and immersed in aerated synthetic seawater, was studied. Galvanic current density measurements, potentiodynamic polarization determinations, and optical and electron microscopic observations were made. Galvanic corrosion of 5086 aluminum was found to be independent of temper and to decrease in the order (of coupled metals) Ti > naval brass> 1040 steel. The effect of dissimilar metal coupling decreases with time due to the formation of corrosion or product deposits on both anodic and cathodic surfaces. Coverage of the surface of the aluminum (anodic) member of couples with corrosion products tends to promote the operation of local corrosion modes. Correlations have been made between corrosion product distribution and the distribution of dissolution attack by microscopic means, and the relation of these features to potential distribution is discussed.Naval Research, Metallurgy Program Office, Code 471N00014-77-WR-70215, NR-036-120Approved for public release; distribution is unlimited

Geology of the Parliament Buildings 5: Geology of the Manitoba Legislative Building

The Manitoba Legislative Building was designed by Frank Worthington Simon, assisted by Henry Boddington III, architects from Liverpool, England. The building style is neoclassical, incorporating Greek, Roman and Egyptian motifs and elements. Construction was completed early in 1920 and the building was dedicated July 15, 1920, on the fiftieth anniversary of the Province. The building is located in central Winnipeg, close to the north bank of the Assiniboine River and rests on 14 m of glacial Lake Agassiz clays over till and limestone bedrock. The mass of the building is supported by 421 concrete caissons that extend through the clays to indurated till or bedrock. Steel frames rest on the caissons and support bearing walls constructed of bricks manufactured from Manitoba shale and clay. Dimension stones decorate the bearing walls inside and outside, and the floors and stairways within. Each type of stone has its own decorative characteristics and each records geologic processes at different times in Earth history. The predominant dimension stone both outside and inside the building is Manitoba Tyndall Stone. Grey, pink and red Tennessee marbles are from the southern Appalachians. Botticino marble was quarried in the foothills of the Alps in northern Italy. Ordovician black marble and Verde Antique are from the Vermont-New York region in the northern Appalachians. Missisquoi marble is from quarries in southern Québec near Philipsburg, and also represents a northern Appalachian source. Bedford limestone, used for most of the statuary, is from south-central Indiana. Butler granite from Ignace, Ontario, was used for steps and floor surfaces of all four porticos. Red marble breccia, used to decorate most fireplaces, may have come from northern France. SUMMAIRE L'édifice du Palais législatif du Manitoba a été conçu par Frank Worthington Simon, assisté de Henry Boddington III, deux architectes de Liverpool en Angleterre. Il s'agit d'un édifice de style néoclassique comprenant des éléments et des motifs grecs, romains et égyptiens. Sa construction s'est achevé au début des années 1920 et son inauguration a eu lieu à l'occasion du cinquantième anniversaire de la Province, soit le 15 juillet 1920. L'édifice est situé au cœur de Winnipeg, non loin de la rive nord de la rivière Assiniboine, la géologie environnante consistant en une couche d'argile du lac Agassiz de 14 m d'épaisseur reposant sur du till et un socle calcaire. Le poids de l'édifice repose sur 421 caissons de béton qui s'enfoncent jusqu'au till consolidé ou jusqu'au socle. Des structures d'acier appuyées sur ces caissons supportent le poids des murs de briques fabriquées avec des schistes argileux et des argiles du Manitoba. Des pierres de taille parent les murs porteurs à l'extérieur comme à l'intérieur ainsi que les planchers et les escaliers intérieurs. Chaque type de pierre de taille présente des caractéristiques particulières, et chacun témoigne de processus géologique d'une époque particulière de l'histoire de la Terre. La pierre de Tyndall est celle qui prédomine tant à l'extérieur qu'à l'intérieur. Les marbres gris, roses et rouges du Tennessee proviennent du Sud de la chaîne des Appalaches. Les marbres de Botticino ont été extraits du piémont des Alpes dans le Nord de l'Italie. Les marbres noirs et les porphyres verts antiques proviennent des États du Vermont et de New York, au Nord des Appalaches. Les marbres de Missisquoi ont été extraits de carrières du Sud du Québec près de Phillipsburg proviennent aussi du Nord des Appalaches. Les calcaires de Bedford qui ont été principalement utilisés comme matériau statuaire proviennent du centre-sud de l'État d'Indiana. Les granites de Butler provenant de Ignace en Ontario ont été utilisés pour les marches et les planchers des quatre portiques. La brèche de marbre rouge qui a été utilisée pour la décoration de la plupart des foyers pourrait provenir du Nord de la France

Chemical and device degradation in PCPDTBT: PCBM solar cells using XPS and ToF-SIMS

Analysis of the degradation routes for PCPDTBT-based solar cells under illumination and in the presence of air have been conducted using a combination of X-ray Photoelectron Spectroscopy (XPS), Time-Of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and solar cell device data. After ageing, XPS studies show that PCPDTBT appears as an oxygen-containing polymer, with data indicating that a break-up in the aromatic rings, formation of sulphates at the thiophene ring, chain scission in the polymer backbone and also loss of side chains. XPS studies on active layers blends of PCPDTBT and PCBM also show significant changes in the vertical composition during ageing, with increased enrichment of PCPDTBT observed at the top surface and that the use of a processing additive (ODT) has a negative impact on the morphological stability. TOF-SIMS has been used to study electrode degradation during ageing experiments leads to migration of indium and tin ions into the active layer in non-inverted devices, but is eliminated for inverted devices.RAEng and EC financial support and Prof TJ Lewis (Bangor) for technical suppor