ABSTRACT. Seven radiocarbon laboratories: Åbo/Aarhus, CIRCE, CIRCe, ETHZ, Poznań, RICH, and Milano-Bicocca performed separation of carbonaceous fractions suitable for

A glass-ceramic composition was designed and tested for use as a sealant in solid oxide fuel cell (SOFC) planar stack design. The crystallization behaviour was investigated by calculating the Avrami parameter (n) and the activation energy for crystallization (E-c) was obtained. The calculated values for n and Ec were 3 and 413.5 kj/mol respectively. The results of thermal analyses indicate that this composition shows no overlap between the sintering and crystallization stages and thus an almost pore-free sealant can be deposited and sintered at 850 degrees C in air for 30 min. A gas tightness test has been carried out at 800 degrees C for 1100 h in dual atmosphere (Ar-H-2 and air) without recording any leakage. Morphological and crystalline phase analyses were conducted prior and following tests in dual atmospheres in order to assess the compatibility of the proposed sealant with the metallic interconnect

Absolute dating of mortars is crucial when trying to pin down construction phases of archaeological sites and historic stone buildings to a certain point in time or to confirm, but possibly also challenge, existing chronologies. To evaluate various sample preparation methods for radiocarbon (14C) dating of mortars as well as to compare different dating methods, i.e. 14C and optically stimulated luminescence (OSL), a mortar dating intercomparison study (MODIS) was set up, exploring existing limits and needs for further research. Four mortar samples were selected and distributed among the participating laboratories: one of which was expected not to present any problem related to the sample preparation methodologies for anthropogenic lime extraction, whereas all others addressed specific known sample preparation issues. Data obtained from the various mortar dating approaches are evaluated relative to the historical framework of the mortar samples and any deviation observed is contextualized to the composition and specific mineralogy of the sampled material.

A brief history of the nature, use and technology of binders in ancient constructions and buildings is outlined, including the apparent chronological discontinuities related to technological developments. The skilled and clever use of mineral resources is at the base of the technical achievements related to architectural activities, from simple adobe to high-performance modern concrete. It is argued that among pre-industrial binders the Roman pozzolanic mortars were highly optimized materials, skillfully prepared and very durable. Their innovative use in architecture is one of the keys of the successful expansion of the Roman Empire. The role of mineralogy and mineral reactions is emphasized in terms of: (1) the preparation and manufacturing of the binding materials; (2) the hardening process and the development of the physical properties of the binder; and (3) the archaeometric reconstruction of the ancient materials.

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In order to radiocarbon (14C) date a building, several components of the mortar could be used, such as the mortar binder, the lime lumps, the charcoal particles and shell fragments eventually present among the aggregates. In particular, the mortar binder requires a purification treatment in order to separate it from other sources of carbon, which could change the 14C signature of the binder invalidating the dating process. Here, we present the application of the Cryo2Sonic method to 14C dating of the ancient building structures unearthed during excavation at the Padua Cathedral complex. The dated samples were pretreated by using Cryo2Sonic method and the improved Cryo2Sonic version 2.0, recently developed by introducing additional steps such as centrifugation of the mortar suspension and gravimetric sedimentation of the binder fractions. The Cryo2Sonic version 2.0 relies heavily on the characterization of the mortar and of the purified binder fractions, allowing the isolation of a reliable 14C datable mortar fraction. Through this new method, the 14C dating of different ancient structures excavated next to the Padua Cathedral allow to identify the first religious complex of the city of Padua (3rd–4th centuries AD).

This work deals with the design, the characterization, and testing of a novel glass-ceramic to be used as sealant for planar solid oxide fuel cells and its compatibility with Mn1.5Co1.5O4-coated Crofer22APU. Thermal, sintering, and crystallization behavior and thermo mechanical properties of the sealant are reviewed and discussed, indicating therefore that these compositions can be deposited at 850C and provide an excellent compatibility with both the Mn1.5Co1.5O4-coated Crofer22APU and the anode-supported electrolyte. In particular, Mn1.5Co1.5O4-coated Crofer22APU/sealant/anode-supported-electrolyte joined samples have been submitted to thermal tests (in air atmosphere) from RT to 800C (SOFC operating temperature) up to 500 h. No interactions, cracks formation, or failure were observed at the Mn1.5Co1.5O4-coated Crofer22APU/sealant interface and between the glass-ceramic and the anode-supported-electrolyte after 500 h of thermal tests in air atmosphere

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