Preliminary geochemical analysis of asbestos minerals from geological and archaeological contexts in Finnmark, north Norway Evaluating the potential for sourcing tempers in asbestos ceramics

Source at http://www.sarks.fi/masf/masf_10/masf_10.html.This is a preliminary study of the potential for sourcing asbestos minerals used as temper in ceramics from Early Metal Age sites in Finnmark, northern Norway. Energy dispersive spectroscopy (EDS/EDX) is used to analyze samples from geological sources and archaeological sites. Although tempers were highly portable, the results of the analysis mostly indicate local procurement, however non-local sources are possible in some cases

Novel biomineralization strategy in calcareous foraminifera

This work shows that calcareous benthic foraminifera are capable of agglutinating sedimentary particles also. In particular, we focus on Melonis barleeanus. Traditionally considered a calcareous species, our data revealed the presence of minute (~3 μm) sedimentary particles (silicate grains) inside the chamber walls of the examined shells. These particles were arranged in a definitive and systematic pattern, and the similar grain chemical characterization and size suggested a relatively high degree of selectivity in both modern and fossil specimens. Based on these results, we propose that M. barleeanus is capable of agglutinating sedimentary particles during the formation of a new chamber. The analysis of other calcareous foraminiferal species (e.g., Cassidulina neoteretis, Lobatula lobatula, Nonionella stella) did not reveal the presence of silicate grains in the shell of the specimens analyzed confirming this to be a characteristic of M. barleeanus. Considering that the isotopic and chemical composition of this species is widely used in paleoclimatic and paleoceanographic reconstructions, we used a mixing model to better constrain the influence of sedimentary particles on M. barleeanus δ18O data. Our model showed that the calcite δ18O would increase by ~0.9–2‰ if 10 wt% of feldspars (i.e., anorthite, albite, orthoclase) and quartz, respectively, were included in the analyzed shell. Based on these results, we emphasize that it is of paramount importance to consider M. barleeanus unusual biomineralization strategy during the interpretation of geological records and to investigate the presence of similar processes in other calcareous foraminiferal species

Preliminary geochemical analysis of asbestos minerals from geological and archaeological contexts in Finnmark, north Norway Evaluating the potential for sourcing tempers in asbestos ceramics

This is a preliminary study of the potential for sourcing asbestos minerals used as temper in ceramics from Early Metal Age sites in Finnmark, northern Norway. Energy dispersive spectroscopy (EDS/EDX) is used to analyze samples from geological sources and archaeological sites. Although tempers were highly portable, the results of the analysis mostly indicate local procurement, however non-local sources are possible in some cases

Risk assessments of aspartame, acesulfame K, sucralose and benzoic acid from soft drinks, “saft”, nectar and flavoured water. Opinion of the Panel on Food Additives, Flavourings, Processing Aids, Materials in Contact with Food and Cosmetics of the Norwegian Scientific Committee for Food Safety

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Strong enhancement of level densities in the crossover from spherical to deformed neodymium isotopes

Understanding the evolution of level densities in the crossover from spherical to well-deformed nuclei has been a long-standing problem in nuclear physics. We measure nuclear level densities for a chain of neodymium isotopes 142,144−151Nd which exhibit such a crossover. These results represent the most complete data set of nuclear level densities to date for an isotopic chain between neutron shell-closure and towards mid-shell. We observe a strong increase of the level densities along the chain with an overall increase by a factor of ≈150 at an excitation energy of 6 MeV and saturation around mass 150. Level densities calculated by the shell model Monte Carlo (SMMC) are in excellent agreement with these experimental results. Based on our experimental and theoretical findings, we offer an explanation of the observed mass dependence of the level densities in terms of the intrinsic single-particle level density and the collective enhancement