Search results for "EAD"

Effect of temperature on the growth of alfa-PbO2 nanostructures

2010

Abstract Ordered arrays of α-PbO 2 nanostructures were grown by galvanostatic anodic deposition into the channels of alumina templates. Electrodepositions were performed in an aqueous solution containing lead acetate and sodium acetate at pH 5.4. Bath temperature and electrodeposition time were varied to check their effect on the growth of nanostructures. It has been found that filling of alumina pores is independent of the time and electrodeposition temperature, whilst height and growth kinetics of nanostructures vary with both parameters. Temperature greatly influences morphology: wires grown at room temperature consisted of clusters of particles, leading to poorly compact structures, whi…

EUA and sCER Phase II Price Drivers: Unveiling the reasons for the existence of the EUA-sCER spread

2011

International audience; This article studies the price relationships between EU emissions allowances (EUAs) - valid under the EU Emissions Trading Scheme (EU ETS) - and secondary Certified Emissions Reductions (sCERs)--established from primary CERs generated through the Kyoto Protocol's Clean Development Mechanism (CDM). Given the price differences between EUAs and sCERs, financial and industrial operators may benefit from arbitrage strategies by buying sCERs and selling EUAs (i.e. selling the EUA-sCER spread) to cover their compliance position as industrial operators are allowed to use sCERs towards compliance with their emissions cap within the European system up to 13.4%. Our central res…

Application of Modified Tafel Analysis to the Identification of Corrosion Products on Archaeological Metals Using Voltammetry of Microparticles

2011

Voltammetry of microparticles is applied to the identification of lead corrosion products by means of an essentially non-invasive 'one-touch' technique based on the use of graphite pencil. This methodology permits the mechanical attachment of few nanograms of sample from the surface of lead archaeological artefacts to a paraffin-impregnated graphite electrode, which, upon immersion in aqueous electrolytes, provides distinctive voltammetric responses for litharge and cotunnite- anglesite-, cerusite-based corrosion products. The reported method is applied to the identification of corrosion products in archaeological lead pieces from different Iberian sites in Valencia (Spain). © 2011 WILEY-VC…

Comercio protohistórico: el registro del Nordeste peninsular y la circulación de mineral de plomo en Ibiza y el Bajo Priorato (Tarragona)

2012

[ES] Los estudios que hemos venido realizando indican que el plomo de la cuenca minera del Bajo Priorato (Tarragona) circula en el ámbito fenicio-tartesio. Sin embargo, los análisis realizados sobre un conjunto de muestras minerales y metálicas de la isla de Ibiza ponen de manifiesto la explotación de la galena argentífera local, cuyo uso coexiste en el yacimiento de sa Caleta con el mineral de Cartagena; no se documenta, en cambio, plomo de procedencia prioratina. Si sumamos a ello los datos relativos a las evidencias que aportan los registros cerámicos ibicencos y catalanes de los ss. VII a VI a.n.e., se va trazando un panorama que pone en evidencia la existencia de una pluralidad de rede…

Book Review of Where Are We Heading? The Evolution of Humans and Things, by Ian Hodder

2019

Tales of saviours and iconoclasts. On the provenance of "the Dead Sea Scrolls of Buddhism"

2021

Academic research on newly discovered ancient Buddhist manuscripts is largely based on objects that come from the antiquities market and to a much lesser degree on objects coming from documented and controlled archaeological excavations. Despite their being unprovenanced, collectors and scholars often present such objects with narratives mimicking provenance. The use of the label "Dead Sea Scrolls" attached to archaeological material without connections to Judaism or early Christianity is a prevalent example of this scholarly praxis. In this article, we deconstruct provenance narratives associated with the undocumented Buddhist manuscripts in the Schøyen Collection and discuss their implica…

Electrochemical Fingerprint of Archeological Lead Silicate Glasses Using the Voltammetry of Microparticles Approach

2016

9 págs.; 14 figs.; 1 tab.

Small anthropomorphic figurines in clay at Gipka neolithic settlements:

2005

Miniature Neolithic figurines in clay are a special topic of research. This especially concerns areas where their representation has so far been poor. While carrying out archaeological excavations in Northern Kurzeme, the north west coastal dune yone of Riga Bay, a ritual-like complex was recovered at Gipka A site belonging to the local Culture of Pit Ceramics. It consists of several large and smaller fireplaces and pits, with the finds of fragmentary clay figurines recovered under the palisade that surrounded the settlement. The head and body of the miniature anthropomorphic figurines in clay have original modelling. It is possible to single out two types of figurine: with rather broad che…

Newly discovered orichalcum ingots from Mediterranean sea: Further investigation

2021

Abstract In February 2016, 47 ingots were found in the seabed of Contrada Bulala (Gela, CL, Italy) near the site where 40 ingots had previously been recovered. The ingots composition was determined to be a Cu - Zn alloy, dated by the archaeologist to the VI century B.C. This specific alloy was then known as Orichalcum. From an archaeological point of view, the first question raised about the new discovery was whether the ingots of the first and the second excavations belonged to the same shipwreck. Following the previous study, an elemental analysis was performed on the ingots from the second finding by using ICP-OS and ICP-MS techniques. The chemometric treatment of the analytical results …

Lead provenance for medieval decorated tile glazes from Brittany and Anjou (13th-14th c.)

2021

International audience; Medieval pavements composed of lead-glazed tiles decorated with a variety of techniques continue to inspire questions about the organisation of glaze manufacture, and the supply and origin of lead materials. The tiles analysed in this study are from Suscinio I (a 13th-century pavement) and Suscinio II (a 14th-century pavement), at the Château of Suscinio in Brittany, and also from the 14th-century pavement at the fortified manor house in Brain-sur-Allonnes, Anjou. Lead isotope analysis (LIA) was used to examine samples from 44 lead-glazed tiles, 29 of which are transparent, while 15 are tin-opacified (an exogenous technique in these regions during this period). Five …