83 research outputs found
Magnetic properties and 57Fe Mössbauer spectroscopy of Mediterranean prehistoric obsidians for provenance studies
No full textSamples from the Mediterranean source-islands: Gyali, Lipari, Melos, Palmarola, Pantelleria and Sardinia (Monte Arci) had their 57Fe M€ossbauer spectra and magnetizations measured. The saturation magnetization (Ms) depends on the island of provenance and it reaches a maximum 0.3 emu/g for Palmarola obsidians, indicating a larger magnetic phase content. The coercive forces (Hc) range from 46 to 372 Oe for respectively samples from Pantelleria and
Palmarola islands. Our analyses show that in a Mr=Ms vs. Hc=Hm plot the data points accumulate in areas that depend on obsidian provenance (Mr, remanent magnetization; Hm, maximum applied field). The M€ossbauer spectra are mainly
composed of broad asymmetric doublets, which were fitted assuming two Fe2þ and one Fe3þ sites. In addition, the
obsidians of Melos and Palmarola present a magnetic component attributed to magnetite and/or hematite. Binary diagrams comparing different Mossbauer hyperfine parameters for the Fe3þ and Fe2þ species gave indications of similarities and differences between obsidians of different origins. Since this kind of plot does not give an unambiguous characterization of samples from each island, a detailed analysis of the M€ossbauer results is in progress using statistical method of clustering analysis as has been shown by Scorzelli et al. [Comptes Rendus Acad. Sci., Serie II, 332 (2001) 769] and Poupeau et al. [IAOS Bull. 28 (2001) 2] in previous studies
SEEA and Ecosystem Services Accounting: A Promising Framework for Territorial Governance Innovation
No full textES rapidly was adopted by quantitative geographers and urban planners as an effective tool to deliver reliable spatial analysis on natural capital and its interaction with citizens and economic ecosystem. Although several relevant applications of ES in planning have been realised, it is still difficult to find a common agreement on how to adopt ES as a standard planning support system. Through a literature review this research aims to highlight how monetizing ecosystem services could be effectively integrated in territorial management practices. The System of Environmental-Economic Accounting (SEEA) framework was identified as a promising tool for this purpose according to its analytical structure based on the integration of national budget, spatial analytics based on ES, and social information characterizing the groups of beneficiaries. It represents an international accounting tools for natural capital appraisal aimed at supporting a holistic decision-making process adopted by UN. In particular, SEEA aims to provide accounting over time to measure the health of the environment, the environment’s contribution to the economy, and the impacts of economic activities on the environment. The research aims to highlight the challenges and opportunities that arise from implementing SEEA in urban planning, providing a critical analysis of the value of ecosystem services with the goal of promoting sustainable practices and nature conservation
Spatial Multi-criteria Analysis for Identifying Suitable Locations for Green Hydrogen Infrastructure
No full textThe paper proposes a Spatial Multi-Criteria Analysis for identifying suitable locations for green hydrogen infrastructure. The production and use of hydrogen as a renewable energy carrier can play a critical role in reducing carbon footprint and increasing energy security in cities worldwide. The approach considers multiple criteria, such as demand, accessibility, environmental impact, and cost, to identify optimal locations for hydrogen production, storage, and distribution facilities. The GIS component enables spatial analysis, allowing visualization and analysis of spatial relationships between potential locations and other relevant factors. The research claims that green hydrogen can significantly improve energy resilience and transform energy systems. The method is applied to a case study, an energy-intensive industry in the city of Potenza (Italy). The result is the map identifying suitable areas where hydrogen production facilities can be located. The approach suggests that urban planners, decision-makers, and stakeholders develop and use green hydrogen as a sustainable energy source
Real time elastosonography in the diagnosis of prostate cancer
No full textTo assess the diagnostic gain of transrectal real time elastography(RTE) compared to transrectal B mode ultrasonography (US) in the detection of tumors in patients suspected of having prostate cancer. Eighty four patients suspected of having prostate cancer on the basis of clinical and biochemical evaluation underwent transrectal US, RRTE and transperineal prostate biopsiy.
RTE is a valid addition to B mode US, and RTE reached a higher accuracy than B mode US in the evaluation of the peripheral zone of the prostate gland and in the selection of appropriate biopsy site
Iron-nickel superstructure in metal particles of Alfianello meteorite
No full textWe report on Mössbauer spectroscopy in metal particles of the Alfianello meteorite. The FeNi 50-50 ordered phase (tetrataenite) was detected in coexistence with a high proportion of the corresponding disordered phase. The order-disorder process is discussed in terms of shock events. © 1994 J.C. Baltzer AG, Science Publishers
The New Peruvian Meteorite Carancas: Mössbauer Spectroscopy and X-Ray Diffraction Studies
No full textThe Carancas meteorite fell on 15 September 2007 approximately 10 km south of Desaguadero, near Lake Titicaca, Peru, producing bright lights, clouds of dust in the sky and intense detonations. The Carancas meteorite is classified as a H4–5 ordinary chondrite with shock stage S3 and a degree of weathering W0. The Carancas meteorite is characterized by well defined chondrules composed either of olivine or pyroxene. The Mössbauer spectra show an overlapping of paramagnetic and magnetic phases. The spectra show two quadrupole doublets associated to olivine and pyroxene; and two magnetic sextets, associated with the primary phases kamacite/taenite and Troilite (Fe2+). Metal particles were extracted from the bulk powdered samples exhibit only kamacite and small amounts of the intergrowth tetrataenite/antitaenite. X-Ray diffractogram shows the primary phases olivine, pyroxene, troilite, kamacite, diopside and albite. Iron oxides has not been detected by Mössbauer spectroscopy or XRD as can be expected for a meteorite immediately recovered after its fall.Fil: Munayco, P.. Centro Brasileiro de Pesquisas Fisicas; BrasilFil: Munayco, J.. Centro Brasileiro de Pesquisas Fisicas; BrasilFil: Varela, Maria Eugenia. Consejo Nacional de Investigaciones CientiÂficas y Tecnicas. Centro Cientifico Tecnologico San Juan. Instituto de Ciencias Astronomicas de la Tierra y del Espacio; ArgentinaFil: Scorzelli, R. B.. Centro Brasileiro de Pesquisas Fisicas; Brasi
Fe2+-Mg order–disorder study in orthopyroxenes from São João Nepomuceno (IVA) iron meteorite
No full textSão João Nepomuceno (SJN) is an iron meteorite belonging to IVA chemical group. It consists of Fe-Ni metal matrix and silicate inclusions made of a coarse-grained mixture of tridymite, orthopyroxene and clinopyroxene. In spite of the extensive work performed on the IVA group there is still no consensus about their origin and its thermal history is subject of ongoing debates. In this work, we report preliminary results on Fe2 + distribution in the non-equivalent octahedral sites in orthopyroxene crystals extracted from São João Nepomuceno in order to infer on the thermal history of this meteorite and therefore acquire more information related to the origin of the IVA iron meteorite group.Fil: Dos Santos, Eder Paulo. Centro Brasileiro de Pesquisas Fisicas; Brasil;Fil: Scorzelli, R. B.. Centro Brasileiro de Pesquisas Fisicas; Brasil;Fil: Varela, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnológico - Conicet - San Juan. Instituto de Ciencias Astronómicas de la Tierra y del Espacio; ArgentinaFil: Munayco, P.. Centro Brasileiro de Pesquisas Fisicas; Brasil
Varre-Sai: The Recent Brazilian Fall
No full textVarre-Sai, the most recent Brazilian meteorite fall, on June 19th, 2010 at Varre-Sai, in Rio de Janeiro State, Brazil (20°51′41″S; 41°44′. 80″W). At least eight masses (total ~3.5 kg) were recovered. Most are totally covered by fusion crust. The exposed interior is of light-grey colour with a few dark shock veins. Five thin polished and etched sections were prepared from a slice weighing 35 g on deposit at the National Museum/UFRJ. It consists mostly of chondrules ranging in size from 0.35 to ~2.2 mm, and chondrule fragments enclosed in a crystalline matrix. The matrix consists of tiny isolated subhedral and anhedral crystals and opaque minerals that are intergrown with broken chondrules. The chondritic texture is poorly defined with chondrule textures that vary from non-porphyritic to porphyritic ones. The essential minerals are olivine (Fa25±0.2) and low-Ca pyroxene (Fa21.66±0.2Wo1.4). Accessory minerals are plagioclase, apatite, Fe-Ni metal phases, troilite, chromite and magnetite. Mössbauer spectroscopy analysis confirms that the mineral phases are olivine, pyroxene, troilite and kamacite/taenite. Chemical data indicate that Varre-Sai is a member of the low iron L chondrite group. The observed texture and mineral phases led us to classify Varre-Sai as an equilibrated petrologic type 5. The shock features of the minerals (undulatory extinction, planar structure and numerous cracks), as well as plagioclase partial or totally transformed to maskelynite, suggest a shock stage S4. Also, some post-impact metamorphic processes could be inferred from the meta-sulfide conjoint grains that show complex mixtures of kamacite-taenite-tetrataenite and troilite. The occurrence of veins crosscutting the studied sections indicates that Varre-Sai was affected by a late fracturing event. Sealing of these fractures must have been a fast process, as shown by troilite globule textures pointing towards rapid solidification. The meteorite name was approved by the Nomenclature Committee of the Meteoritical Society (Meteoritic Bulletin, no 99).Fil: Zucolotto, M. E.. Universidade Federal Do Rio de Janeiro. Museu Nacional; BrasilFil: Antonello, L. L.. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Varela, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Scorzelli, R. B.. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Munayco, P.. Centro Brasileiro de Pesquisas Físicas; BrasilFil: dos Santos, E.. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Ludka, Isabel P.. Universidade Federal do Rio de Janeiro; Brasi
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