26 research outputs found

    Overview of the techniques used for the study of non-terrestrial bodies: Proposition of novel non-destructive methodology

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    Meteorites and impact glasses have been largely analysed using different techniques, but most studies have been focused on their geologicalemineralogical characterization and isotopic ratios, mainly of a destructive nature. However, much more information can be gained by applying novel non-destructive analytical procedures and techniques that have been scarcely used to analyse these materials. This overview presents some new methodologies to study these materials and compares these new approaches with the commonly used ones. Techniques such as X-Ray Fluorescence (XRF) and Laser Induced Breakdown Spectroscopy (LIBS), for elemental characterization, the hyphenated Raman spectroscopy- SEM/EDS and the combination of them, allow extracting simultaneous information from elemental, molecular and structural data of the studied sample; furthermore, the spectroscopic image capabilities of such techniques allow a better understanding of the mineralogical distribution. © 2017 Elsevier B.V. All rights reserved.Ministerio de Economía, Industria y Competitividad (project ESP2014-56138-C3-2-R

    Are children playgrounds safe play areas? Inorganic analysis and lead isotope ratios for contamination assessment in recreational (Brazilian) parks

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    In city playgrounds, there is a potential risk of harming children’s health by contamination coming from anthropogenic activities. With the aim to determinate the sources and the risk of hazardous elements, soil samples were collected in 19 selected playgrounds of different urban and rural areas from the Rio Grande do Sul state (Brazil). The concentration of 23 metals and metalloids and lead isotopic ratios were determined by ICP-MS. The methodology proposed here, firstly, classified the parks according to the average metal content by means of the NWACs (Normalized-and-Weighted Average Concentrations) and assess the contamination risk determining the Contamination Factors (CFs). Finally, statistical tools (correlation analysis and principal component analysis) were used to identify the most important contamination sources. The statistical tools used, together with lead isotopic composition analysis of the samples, revealed that coal combustion is the main source of contamination in the area. Vegetation was identified as a barrier for the contamination coming from the city. Nonetheless, some of the soils present a possible toxicological risk for humans. In fact, Cr, Sb, and Pb concentrations were higher than the Residential Intervention Values (VIRs) defined by the Environmental Protection Agency of the State of São Paulo, also in Brazil

    A new semi-quantitative Surface-Enhanced Raman Spectroscopy (SERS) method for detection of maleimide (2,5-pyrroledione) with potential application to astrobiology

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    Nitrogen-containing heterocyclic compounds are fundamental biochemical components of all life on Earth and, presumably, life elsewhere in our solar system. Detection and characterization of these compounds by traditional solvent extraction, chromatographic separation, and GC–MS analysis require more sample mass than will be available from samples returned to Earth from Mars. With its small sample mass requirement, Surface Enhanced Raman Spectroscopy could be an appropriate technique for analysis of returned samples. We have developed a SERS method for the detection of maleimide (2,5-pyrroledione), an N-containing heterocycle with a structure that is widespread in biochemicals. This semi-quantitative methodology accurately determines maleimide concentration in the range from 60 ”g/mL to 120 ”g/mL. We present a maleimide SERS standard spectrum which will be useful as a reference for future works. The present work demonstrates an easy, accurate, and effective method for the non-destructive qualitative and semi-quantitative study of maleimide as a first step toward developing a method for analysis of related compounds

    The effect of calcium oxalates in the weathering steel surface

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    Bioimpact on weathering steel surfaces: Oxalates formation and the elucidation of their origin

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    International audienceThis study was carried out to elucidate the causes of irregularities and discolorations on the surface of parts of a weathering steel sculpture which had been in contact with wood pallets. Non-destructive analysis of the samples by Raman spectroscopy revealed the presence of iron oxalates and calcium oxalates. Thermodynamic modeling suggested that the detected oxalates were produced by the reaction of oxalic acid, a potential metabolite excreted by microorganisms, and elements present in the steel surface such as iron. Carotenoids including ÎČ-carotene and astaxanthin, biomarkers for a large number of prokaryotic and eukaryotic microorganisms, were also detected in samples

    A Proposed advertising plan for San Miguel packaging products

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    The proposed 1995 SMPP Advertising Plan primarily focuses on San Miguel Packaging Products as a company. SMPP experienced a negative growth in 1992 and a declining share in SMC\u27s Total Revenues. The advertising campaign serves to reinforce SMPP\u27s marketing efforts in stimulating the demand for SMPP products. The plan intends to reach 95 percent of the target market creating a top of mind awareness level and instilling the idea that SMPP symbolizes a long history of multi-packaging superiority. Popular mediums (Audio-Visual Presentation, brochures, print ads, direct mail) in industrial advertising and a non-traditional form (fax advertising) shall be used. All ads will revolve around a lion analogy theme and the SMPP (Strong Mark of Packaging Perfection) cronym. However, the company brochure will also include analogies between an animal and specific package. Print ads and new will be released in leading broadsheets and magazines. The campaign also incorporates public relations and promotional recommendations to complement advertising efforts. Public relations will involve sponsorship of various sports and social activities, participation in exhibits and socio-civic projects. Advertorials and press releases will run throughout the year. The campaign will run from January 1 to December 1995. The entire plan covers a P 9,778,176 advertising budget and a P 5,558,200 Public Relations & Promotions budget. This is inclusive of production costs, media placements and contingency cost

    Protective ability index measurement through Raman quantification imaging to diagnose the conservation state of weathering steel structures

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    International audienceWeathering steel was designed to resist against the atmospheric impact due to the development of a characteristic rust layer that protects the metal by reducing the corrosion rate. This rust layer is formed by different iron (oxy-hydr)oxides that acts as a barrier and provides the protective ability. In order to check the conservation state trough the protective capability, it is necessary to calculate the so-called protective ability index (PAI). It mainly takes into account the ratio (α/Îł) between the mass of goethite (α-FeOOH) and lepidocrocite (Îł-FeOOH), present in the rust layer of weathering steel. Raman spectroscopy, apart from a qualitative technique, is recently becoming a semi quantitative approach. Therefore, it is a valuable tool for the calculation of the mentioned index. This paper is a widening of a previous work in which it was uncovered a problem in different weathering steel sculptures which are exposed to a Cl− and SO2-rich urban atmosphere because they present different esthetical problems on their surfaces, such as detachments of steel chips, discolorations and irregularities. In order to relate these problems on the surface and the rust layer composition, PAI calculations were performed from the phase identification obtained from Raman imaging and using spectra decomposition to quantify each compounds. Although goethite and lepidocrocite were the most commonly detected compounds, hematite, akaganeite and magnetite were also identified. Hematite is a sub product formed in rich SO2 atmospheres; therefore, a PAI with its content is proposed. Protective indexes obtained for the different artworks exposed in different places provide quantitative clues for the conservation diagnosis of weathering steel structures
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