Stony materials

The bulk of the Pu and Am is very tenaciously held by the stony materials studied (tuff, basalt, limestone). This is evidenced by ... 

Concrete is a composite material made from cement paste and aggregate (a coarse, stony material). The composition of concrete varies widely and depends on the intended application but always contains cement, water and aggregate. The mixture of cement, water and sand is called mortar, whereas cement and water alone constitute cement paste. 

Keywords Stony materials Alteration processes Decay assessment Intervention strategy Dating Materials treatment and replacanent SustainabiUty... 

The present review will focus on strategic and tactical aspects of the interventions in relation to the characteristics of the alteration processes. In a perspective of Environmental Chemistry for a Sustainable World it will be focused on the relevance of the understanding of the problem (diagnosis) including the characterisation of the materials and alteration agents, the substances used in the interventions and sustainability aspects related to these interventions. This review will be mostly focused on alteration processes that affect stony materials and the interventions in these materials and its surroundings (including atmosphere, terrain and structures) with a view towards the conservation of the stony materials. Interventions for stabil-... 

Another final reflection concerns the, perhaps expectable, trend in research for laboratory controlled essays of small clean specimens but the consequence is that there is poor information on the behaviour of the product on real-scale objects under field conditions, a feature that adds to the previous one on the need for long-term assessments. Additionally, a trend that must not be favoured, at least in stony materials, is the comparison of procedures based on one specimen by treatment given the variations of properties on these materials. 

Sanjurjo-Sanchez J, Alves C (2011) Decay effects of pollutants on stony materials in the built environment. Environ Chem Lett 10(2) 131-143. doi 10.1007/sl0311-011-0346-y Sanjurjo-Sanchez J, Alves C (2012) PoUutant-induced decay of building materials. In Lichtfouse E, Schwarzbauer J, Robert D (eds) Environmental chemistry for a sustainable world. Springer, Dordrecht, pp 47-120. doi 10.1007/978-94-007-2439-6 2 Sanjurjo-Sanchez J, Trindade MJ, Blanco-Rotea R, Benavides R, Fernandez Mosquera D, Burbridge Cl, Prudencio Ml, Dias Ml (2010) Chemical and mineralogical characterization of historic mortars from the Santa Eulalia de Boveda temple, NW Spain. J Archaeol Sci 37 2346-2351. doi 10.1016/j.jas.2010.04.008... 

Occurrence and Recovery. Rhenium is one of the least abundant of the naturally occurring elements. Various estimates of its abundance in Earth s cmst have been made. The most widely quoted figure is 0.027 atoms pet 10 atoms of silicon (0.05 ppm by wt) (3). However, this number, based on analyses for the most common rocks, ie, granites and basalts, has a high uncertainty. The abundance of rhenium in stony meteorites has been found to be approximately the same value. An average abundance in siderites is 0.5 ppm. In lunar materials, Re, when compared to Re, appears to be enriched by 1.4% to as much as 29%, relative to the terrestrial abundance. This may result from a nuclear reaction sequence beginning with neutron capture by tungsten-186, followed by p-decay of of a half-hfe of 24 h (4) (see Extraterrestrial materials). 

If the mineral matter in the coal exceeds about 40%, then the material is referred to as a coaly or carbonaceous shale. If the mineral matter is a finely divided clay, well dispersed in the coal, then the material may be described as a stony coal or bone coal. 

Nicolas Dupre was born in Chatillon-sous-Bagneux, France, in 1975. He received his Ph.D. (2001) degree from Universite Pierre et Marie Curie-Paris VI working under the direction of Professor Michel Quarton. He was appointed as a postdoctoral associate at SUNY Stony Brook in 2002, where he works with Professor Clare P. Grey. His current research interests are focused on the study of the behavior of materials for lithium batteries using solid-state NMR. 

As pointed out by Stephens and Goldman (State University of New York at Stony Brook). Quasicrystals are neither uniformly ordered like crystals nor amorphous like glasses. Many features of quasicrystals cun be explained, but their atomic structure remains to be described fully. See also Aluminum Alloys and Engineered Materials... 

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