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1.
Proc Natl Acad Sci U S A ; 117(28): 16243-16249, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32571903

RESUMO

This study investigates glass finds from the Iberian Peninsula as a proxy for identifying the mechanisms underlying technological transformations and innovation in the wake of the Arab conquest in the seventh and eighth centuries CE. High-resolution laser ablation inductively coupled plasma mass spectrometry data combined with lead isotope analyses of a precisely dated (mid-eighth century to 818 CE) glass assemblage from the Rabad of Saqunda in Cordoba, capital of Umayyad Spain, enabled us to trace the origins of an Iberian glassmaking industry and to unambiguously link it to the exploitation of local raw materials. The analytical data reveal increased recycling, some isolated imports of Islamic plant ash glasses from Mesopotamia, and, most notably, the development of a new type of glassmaking technology that resorted to the use of lead slag from silver and lead mining and processing in the region around Cordoba. The production of this type of lead glass from Saqunda was short-lived and was subsequently refined by introducing additional fluxing agents. The technological innovation of Islamic glassmaking in Spain evidently drew inspiration from adjacent high-temperature technologies. The revival of glass and the development of a local glassmaking tradition was indirectly related to the wider processes of Islamization, such as the introduction of glazed ceramics that are compositionally related to the lead glasses from Saqunda.

2.
PLoS One ; 17(4): e0265242, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35413061

RESUMO

The identity of artists and localisation of workshops are rarely known with certainty before the mid-15th century. We investigated the material used by one of the most prolific and enigmatic medieval sculptors, the Master of the Rimini Altarpiece or Master of Rimini, active around 1420-40. The isotope fingerprints (Sr, S and O) of a representative corpus of masterpieces but also minor artworks, attributed to the Master of Rimini and his workshop, are virtually identical, demonstrating the unity of the corpus and a material evidence behind the stylistic and iconographic ascriptions. The material used is exclusively Franconian (N-Bavarian) alabaster, 600 km distant from the supposed zone of activity of the Master of Rimini workshop according to recent literature. The same material was later used by the prominent Late Medieval German carver Tilman Riemenschneider, active in Würzburg after 1483, whose small corpus of alabaster sculptures we have been able to characterize almost entirely. Based on these findings, we propose here an alternative to the prevailing hypothesis of a Flemish or N-French workshop being founded on similarities of the Rimini sculpture with motives in Flemish and French painting. Our scenario, returning to the initial proposal of a German localisation of the Master of Rimini workshop, assumes the migration of an artist, perhaps trained in the Low Countries or strongly inspired by the Flemish art, to Southern Germany where he founded a highly productive export workshop, well situated on the crossroads of medieval trade, with a pan-European radiance. This study sheds a spotlight on the on the trade networks of luxury goods, the raw material used for their production, and the high-end art market in Europe as well as on international migration of artists and styles, at the eve of the Renaissance.


Assuntos
Sulfato de Cálcio , Pinturas , Europa (Continente) , Alemanha , História do Século XV , Humanos , Masculino , Pessoa de Meia-Idade , Pinturas/história , Escultura/história
3.
Nat Commun ; 13(1): 4172, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35882851

RESUMO

Rechargeable lithium-ion batteries (LIB) play a key role in the energy transition towards clean energy, powering electric vehicles, storing energy on renewable grids, and helping to cut emissions from transportation and energy sectors. Lithium (Li) demand is estimated to increase considerably in the near future, due to the growing need for clean-energy technologies. The corollary is that consumer expectations will also grow in terms of guarantees on the origin of Li and the efforts made to reduce the environmental and social impact potentially associated with its extraction. Today, the LIB-industry supply chain is very complex, making it difficult for end users to ensure that Li comes from environmentally and responsible sources. Using an innovative geochemical approach based on the analysis of Li isotopes of raw and processed materials, we show that Li isotope 'fingerprints' are a useful tool for determining the origin of lithium in LIB. This sets the stage for a new method ensuring the certification of Li in LIB.

4.
Sci Total Environ ; 619-620: 272-280, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29149751

RESUMO

"Man-made" or unconventional freshwater, like desalinated seawater or reclaimed effluents, is increasingly introduced into regional water cycles in arid or semi-arid countries. We show that the breakthrough of reverse osmosis-derived freshwater in the largely engineered water cycle of the greater Tel Aviv region (Dan Region) has profoundly changed previous isotope fingerprints. This new component can be traced throughout the system, from the drinking water supply, through sewage, treated effluents, and artificially recharged groundwater at the largest Soil-Aquifer Treatment system in the Middle East (Shafdan) collecting all the Dan region sewage. The arrival of the new water type (desalinated seawater) in 2007 and its predominance since 2010 constitutes an unplanned, large-scale, long-term tracer test and the monitoring of the breakthrough of desalination-specific fingerprints in the aquifer system of Shafdan allowed to get new insights on the water and solute flow and behavior in engineered groundwater systems. Our approach provides an investigation tool for the urban water cycle, allowing estimating the contribution of diverse freshwater sources, and an environmental tracing method for better constraining the long-term behavior and confinement of aquifer systems with managed recharge.

5.
Isotopes Environ Health Stud ; 43(3): 179-96, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17786665

RESUMO

Strontium isotope ratios and Ca2+, Na+, K+, Mg2+, Cl-, SO4(2-), NO3- and Sr2+ concentrations were measured in rainwater samples collected in four stations in France (Brest, Dax, Orleans and Clermont-Ferrand) over a period of 1 year. Each sample represented a monthly series of rain events. The chemical composition and the 87Sr/86Sr ratios of the rainwater samples varied considerably. Using Na concentrations as an indicator of marine origin, the proportion of marine and crustal elements was estimated from elemental ratios. Strontium isotopes were used to characterize the different sources using data from the four stations and the literature. Such sources include sea salts, crustal sources (carbonates, silicates and volcanic rocks) and anthropogenic sources (fertilizers, automobile exhausts, incinerators and urban heating).


Assuntos
Chuva , Isótopos de Estrôncio/química , França
6.
Sci Total Environ ; 566-567: 398-415, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27232967

RESUMO

The Roussillon sedimentary Basin (South France) is a complex multi-layered aquifer, close to the Mediterranean Sea facing seasonally increases of water abstraction and salinization issues. We report geochemical and isotopic vertical variability in this aquifer using groundwater sampled with a Westbay System® at two coastal monitoring sites: Barcarès and Canet. The Westbay sampling allows pointing out and explaining the variation of water quality along vertical profiles, both in productive layers and in the less permeable ones where most of the chemical processes are susceptible to take place. The aquifer layers are not equally impacted by salinization, with electrical conductivity ranging from 460 to 43,000µS·cm(-1). The δ(2)H-δ(18)O signatures show mixing between seawater and freshwater components with long water residence time as evidenced by the lack of contribution from modern water using (3)H, (14)C and CFCs/SF6. S(SO4) isotopes also evidence seawater contribution but some signatures can be related to oxidation of pyrite and/or organically bounded S. In the upper layers (87)Sr/(86)Sr ratios are close to that of seawater and then increase with depth, reflecting water-rock interaction with argillaceous formations while punctual low values reflect interaction with carbonate. Boron isotopes highlight secondary processes such as adsorption/desorption onto clays in addition to mixings. At the Barcarès site (120m deep), the high salinity in some layers appear to be related neither to present day seawater intrusion, nor to Salses-Leucate lagoonwater intrusion. Groundwater chemical composition thus highlights binary mixing between fresh groundwater and inherited salty water together with cation exchange processes, water-rock interactions and, locally, sedimentary organic matter mineralisation probably enhanced by pyrite oxidation. Finally, combining the results of this study and those of Caballero and Ladouche (2015), we discuss the possible future evolution of this aquifer system under global change, as well as the potential management strategies needed to preserve quantitatively and qualitatively this water resource.

7.
Environ Sci Technol ; 42(13): 4723-31, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18677997

RESUMO

A systematic measurement of ions and 2H/1H, 7Li/6Li, 11B/10B, 18O/ 16O, and 87Sr/86Sr isotopes in feed-waters, permeates, and brines from commercial reverse osmosis (RO) desalination plants in Israel (Ashkelon, Eilat, and Nitzana) and Cyprus (Larnaca) reveals distinctive geochemical and isotopic fingerprints of fresh water generated from desalination of seawater (SWRO) and brackish water (BWRO). The degree of isotope fractionation during the passage of water and solutes through the RO membranes depends on the medium (solvent-water vs. solutes), chemical speciation of the solutes, their charge, and their mass difference. O, H, and Sr isotopes are not fractionated during the RO process. 7Li is preferentially rejected in low pH RO, and B isotope fractionation depends on the pH conditions. Under low pH conditions, B isotopes are not significantly fractionated, whereas at high pH, RO permeates are enriched by 20 per thousand in 11B due to selective rejection of borate ion and preferential permeation of 11B-enriched boric acid through the membrane. The specific geochemical and isotopic fingerprints of SWRO provide a unique tool for tracing "man-made" fresh water as an emerging recharge component of natural water resources.


Assuntos
Boro/análise , Deutério/análise , Água Doce/química , Íons/análise , Lítio/análise , Oxigênio/análise , Água do Mar/química , Estrôncio/análise , Chipre , Isótopos/análise , Israel , Osmose , Purificação da Água
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