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Artigos de revistas sobre o assunto "86Sr isotopic ratio"

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Gregorčič, Staša Hamzić, Nives Ogrinc, Russell Frew, Marijan Nečemer, Lidija Strojnik e Tea Zuliani. "The Provenance of Slovenian Milk Using 87Sr/86Sr Isotope Ratios". Foods 10, n.º 8 (27 de julho de 2021): 1729. http://dx.doi.org/10.3390/foods10081729.

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This work presents the first use of Sr isotope ratios for determining the provenance of bovine milk from different regions of Slovenia. The analytical protocol for the determination of 87Sr/86Sr isotope ratio was optimised and applied to authentic milk samples. Considerable variability of 87Sr/86Sr ratios found in Slovenian milk reflects the substantial heterogeneity of the geological background of its origin. The results, although promising, cannot discount possible inter-annual or annual variation of the Sr isotopic composition of milk. The 87Sr/86Sr ratios of groundwater and surface waters are in good correlation with milk, indicating that the Sr isotopic fingerprint in milk is reflective of cow drinking water. The 87Sr/86Sr ratio has the potential to distinguish between different milk production areas as long as these areas are characterised by geo-lithology. Discriminant analysis (DA) incorporating the elemental composition and stable isotopes of light elements showed that 87Sr/86Sr ratio together with δ13Ccas and δ15Ncas values have the main discrimination power to distinguish the Quaternary group (group 6) from the others. Group 1 (Cretaceous: Carbonate Rocks and Flysch) is associated with Br content, 1/Sr and δ18Ow values. The overall prediction ability was found to be 63.5%. Pairwise comparisons using OPLS-DA confirmed that diet and geologic parameters are important for the separation.
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Nguyen Thi Kim, Dung, e Thuy Thai Thi Thu. "Study on the removal of interferences for the determination of ⁸⁷Sr/⁸⁶Sr isotopic ratio in petroleum drill-hole water samples using isotope dilution – inductively coupled plasma mass spectrometry (ID – ICP-MS)". Nuclear Science and Technology 8, n.º 4 (1 de setembro de 2021): 34–43. http://dx.doi.org/10.53747/jnst.v8i4.65.

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87Sr/86Sr isotopic ratio is one of the useful tools that can authenticate the original source of the natural products from the earth-created and/or geological processes. However, the effect of interferences in petroleum drill-holes water sample such as thickness of sample matrix or isotopic signal of 87Rb might cause the low precision of 87Sr/86Sr determination using quadrupole inductively coupled plasma spectrometry (ICP-MS). The elimination of these mentioned effects was thus studied by using the ion - exchange chromatography. Calcium in sample matrix was separated on anionite column (Bio-Rad AG1-X8 resin) in methanol medium with the high efficiency while rubidium wasremoved from strontium on cation exchange resin (Bio-Rad AG50-X8) with strontium recovery over 99%. The isotope dilution technique with 86Sr - enriched isotopic standard solution was used for the control of separation process. The 87Sr/86Sr isotopic ratio was thus determined using ICP-MS with the signal correction by a strontium isotopic ratio standard reference material (NIST SRM 987).
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Wu, W. H., H. B. Zheng e J. D. Yang. "Sr isotopic characteristics in two small watersheds draining typical silicate and carbonate rocks: implication for the studies on seawater Sr isotopic evolution". Hydrology and Earth System Sciences Discussions 10, n.º 6 (21 de junho de 2013): 8031–69. http://dx.doi.org/10.5194/hessd-10-8031-2013.

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Abstract. We systematically investigated Sr isotopic characteristics of small silicate watershed – the tributary Xishui River of the Yangtze River, and small carbonate watershed – the tributary Guijiang River of the Pearl River. The results show that the Xishui River has relatively high Sr concentrations (0.468–1.70 μmol L−1 in summer and 1.30–3.17 μmol L−1 in winter, respectively) and low 87Sr/86Sr ratios (0.708686–0.709148 in summer and 0.708515–0.709305 in winter), which is similar to the characteristics of carbonate weathering. The Guijiang River has low Sr concentrations (0.124–1.098 μmol L−1) and high 87Sr/86Sr ratios (0.710558–0.724605), being characterized by silicate weathering. In the Xishui River catchment, chemical weathering rates in summer are far higher than those in winter, indicating significant influence of climate regime. However, slight differences of 87Sr/86Sr ratios between summer and winter show that influence of climate on Sr isotope is uncertainty owing to very similar Sr isotope values in silicate and carbonate bedrocks. As 87Sr/86Sr ratios in the Xishui River are lower than those in seawater, they will decrease 87Sr/86Sr ratio of seawater after transported into oceans. Previous studies also showed that some basaltic watersheds with extremely high chemical weathering rates reduced the seawater Sr isotope ratios. In other words, river catchments with high silicate weathering rates do not certainly transport highly radiogenic Sr into oceans. Therefore, it may be questionable that using the variations of seawater 87Sr/86Sr ratio to indicate the continental silicate weathering intensity. In the Guijiang River catchment, 87Sr/86Sr ratios of carbonate rocks and other sources (rainwater, domestic and industrial waste water, and agricultural fertilizer) are lower than 0.71. In comparison, some non-carbonate components, such as, sand rocks, mud rocks, shales, have relatively high Sr isotopic compositions. Moreover, granites accounted for only 5% of the drainage area have extremely high 87Sr/86Sr ratios with an average of over 0.8. Therefore, a few silicate components contained in carbonate rocks obviously increases the Sr isotopic compositions of the river water, and results in a positive effect on the rise of 87Sr/86Sr ratio of seawater. Therefore, the relation between Sr isotope evolution of seawater and continental weathering rate is complex, 87Sr/86Sr ratios of underlying bedrock in catchment could be an important controlling factors.
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Rossi, Mattia, Paola Iacumin e Gianpiero Venturelli. "87Sr/86Sr Isotope Ratio as a Tool in Archaeological Investigation: Limits and Risks". Quaternary 7, n.º 1 (11 de janeiro de 2024): 6. http://dx.doi.org/10.3390/quat7010006.

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During the last forty years, the use of strontium isotopes in archaeology and biogeochemical research has spread widely. These isotopes, alone or in combination with others, can contribute to trace past and present environmental conditions. However, the interpretation of the isotopic values of strontium is not always simple and requires good knowledge of geochemistry and geology. This short paper on the use of strontium isotopes is aimed at those who use this tool (archaeologists, but not only) but who do not have a thorough knowledge of mineralogy, geology, and geochemistry necessary for a good understanding of natural processes involving these isotopes. We report basic knowledge and suggestions for the correct use of these isotopes. The isotopic characteristics of bio-assimilable strontium depend not so much on the isotopic characteristics of the bulk rock as, rather, on those of its more soluble minerals. Before studying human, animal and plant remains, the state of conservation and any conditions of isotopic pollution should be carefully checked. Samples should be collected according to random sampling rules. The data should be treated by a statistical approach. To make comparisons between different areas, it should be borne in mind that the study of current soils can be misleading since the mineralogical modification of soil over time can be very rapid.
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Alekseeva, L. P., e S. V. Alekseev. "Strontium and 87Sr/86Sr isotopic ratio of ground brines in the northeastern Angara-Lena artesian basin". Earth sciences and subsoil use 44, n.º 2 (17 de junho de 2021): 98–105. http://dx.doi.org/10.21285/2686-9993-2021-44-2-98-105.

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The purpose of this study is to identify the major formation processes of the ionic and isotopic composition of chloride brines in the sedimentary basins of the Siberian platform. The object and subject of research are deep-seated strong, very strong and extremely saturated brines as well as their strontium content and the ratio of Sr stable isotopes. The groundwater ionic-salt composition was determined by traditional methods (titrimetric, gravimetric, flame photometry), the 87Sr/86Sr isotopic ratio was measured using mass-spectrometers (Irkutsk, Russia and Canada). The brines lying at the depth of 1500–3000 m were tapped and classified into saline and subsalt hydrogeological formations. Their feature is high salinity (385–530 g/L) and high content of strontium (2.3–7 g/L). The 87Sr/86Sr isotopic ratio ranges from 0.708 to 0.713062. By isotopic composition most of the brine samples are close to the waters of the Vendian-Cambrian paleoocean. However, some brine samples from the subsalt part of the sedimentary section of the basin are significantly enriched in the isotope 87Sr compared to the paleoocean waters and other samples. It could be due to the substantial input of 87Sr into the brines during the long-term interaction of groundwater with the host Lower Cambrian sandstones.
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Wu, W. H., H. B. Zheng, J. H. Cao e J. D. Yang. "Sr isotopic characteristics in two small watersheds draining silicate and carbonate rocks: implication for studies on seawater Sr isotopic evolution". Hydrology and Earth System Sciences 18, n.º 2 (13 de fevereiro de 2014): 559–73. http://dx.doi.org/10.5194/hess-18-559-2014.

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Abstract. We systematically investigated the Sr isotopic characteristics of a small silicate watershed, the Xishui River a tributary of the Yangtze River, and a small carbonate watershed, the Guijiang River a tributary of the Pearl River. The results show that the two rivers have uncommon Sr isotopic characteristics compared with most small watersheds. Specifically, the silicate watershed (Xishui River) has relatively high Sr concentrations (0.468 to 1.70 μmol L−1 in summer and 1.30 to 3.17 μmol L−1 in winter, respectively) and low 87Sr/86Sr ratios (0.708686 to 0.709148 in summer and 0.708515 to 0.709305 in winter). The carbonate watershed (Guijiang River) has low Sr concentrations (0.124 to 1.098 μmol L−1) and high 87Sr/86Sr ratios (0.710558 to 0.724605). As the 87Sr/86Sr ratios in the Xishui River are lower than those in seawater, the 87Sr/86Sr ratio of seawater will decrease after the river water is transported to the oceans. Previous studies have also shown that some basaltic watersheds with extremely high chemical weathering rates reduced the seawater Sr isotope ratios. In other words, river catchments with high silicate weathering rates do not certainly transport highly radiogenic Sr into oceans. Therefore, the use of the variations in the seawater 87Sr/86Sr ratio to indicate the continental silicate weathering intensity may be questionable. In the Guijiang River catchment, the 87Sr/86Sr ratios of carbonate rocks and other sources (rainwater, domestic and industrial waste water, and agricultural fertilizer) are lower than 0.71. In comparison, some non-carbonate components, such as sand rocks, mud rocks, and shales, have relatively high Sr isotopic compositions. Moreover, granites accounted for only 5% of the drainage area have extremely high 87Sr/86Sr ratios with an average of greater than 0.8. Therefore, a few silicate components in carbonate rocks obviously increase the Sr isotopic compositions of the river water.
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Cellier, Robin, Sylvain Bérail, Julien Barre, Ekaterina Epova, Anne-Laure Ronzani, Cornelis Van Leeuwen, Stanislas Milcent, Patrick Ors e Olivier F. X. F. X. Donard. "Specificity and Origin of the Stability of the Sr Isotopic Ratio in Champagne Wines". Molecules 26, n.º 16 (23 de agosto de 2021): 5104. http://dx.doi.org/10.3390/molecules26165104.

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The 87Sr/86Sr ratio of 39 Champagnes from six different brands, originating from the whole “Appellation d’Origine Contrôlée” (AOC) Champagne was analyzed to establish a possible relation with the geographical origin. Musts (i.e., grape juice) and base wines were also analyzed to study the evolution of the Sr isotopic ratio during the elaboration process of sparkling wine. The results demonstrate that there is a very homogeneous Sr isotopic ratio (87Sr/86Sr = 0.70812, n = 37) and a narrow span of variability (2σ = 0.00007, n = 37). Moreover, the Sr concentrations in Champagnes have also low variability, which can be in part explained by the homogeneity of the bedrock in the AOC Champagne. Measurements of the 87Sr/86Sr ratio from musts and base wines show that blending during Champagne production plays a major role in the limited variability observed. Further, the 87Sr/86Sr of the musts were closely linked to the 87Sr/86Sr ratio of the vineyard soil. It appears that the 87Sr/86Sr of the product does not change during the elaboration process, but its variability decreases throughout the process due to blending. Both the homogeneity of the soil composition in the Champagne AOC and the blending process during the wine making process with several blending steps at different stages account for the unique and stable Sr isotopic signature of the Champagne wines.
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Bujakaite, M. I., V. Yu Lavrushin e B. G. Pokrovsky. "Strontium isotopic composition in waters of mud volcanoes of Azerbaijan". Литология и полезные ископаемые, n.º 5 (20 de outubro de 2019): 391–403. http://dx.doi.org/10.31857/s0024-497x20195391-403.

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The isotopic composition of strontium was studied in the waters of 22 Azerbaijan mud volcanoes, in which the isotope composition of oxygen and hydrogen, as well as the concentration of macro and micro elements, was previously [Lavrushin et al., 2015] determined. 87Sr/86Sr ratios in the waters of Azerbaijan mud volcanoes are within 0.70670.7083. The minimum ratio was established in Neftechala Yuzhnaya volcano, located in the south of the territory ‒ in the Kura region, which is characterized by the lowest average values of 87Sr/86Sr = 0.70700.0003 and 18O = 2.01.8 compared to volcanoes situated northern ‒ in Shemakha ‒ Gobustan, Absheron and Caspian regions (87Sr/86Sr average = 0.70760.0005, 18O average = 4.82.5). The relation between the strontium isotopic composition and the isotopic composition of oxygen suggests that the formation of the isotopic characteristics of the mud volcanic waters of Azerbaijan involves two main sources, one of which is predominantly associated with sedimentary carbonates of Cretaceous-Paleogene age, and the second, prevailing in the Kura region, has traces of isotopic exchange with volcanic rocks. The role of strontium dissolved in the sea water, as well as strontium, which could be extracted from modern terrigenous sediments of the Caspian Sea and terrigenous clay rocks of the Maikop series in the mud volcanic waters of Azerbaijan is insignificant.
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Sighinolfi, Simona, Caterina Durante, Lancellotti Lisa, Lorenzo Tassi e Andrea Marchetti. "Influence of Chemical and Physical Variables on 87Sr/86Sr Isotope Ratios Determination for Geographical Traceability Studies in the Oenological Food Chain". Beverages 4, n.º 3 (1 de agosto de 2018): 55. http://dx.doi.org/10.3390/beverages4030055.

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This study summarizes the results obtained from a systematic and long-term project aimed at the development of tools to assess the provenance of food in the oenological sector. 87Sr/86Sr isotope ratios were measured on a representative set of soils, branches, and wines sampled from the Chianti Classico wine production area. In particular, owing to the high spatial resolution of the 87Sr/86Sr ratio in the topsoil, the effect of two mill techniques for soil pretreatment was investigated to verify the influence of the particle dimension on the measured isotopic ratios. Samples with particle sizes ranging from 250 to less than 50 µm were investigated, and the extraction was performed by means of the DIN 19730 procedure. For each sample, the Sr isotope ratio was determined as well. The obtained results showed that the 87Sr/86Sr ratio is not influenced by soil particle size and may represent an effective tool as a geographic provenance indicator for the investigated product.
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Baffi, C., e P. R. Trincherini. "Food traceability using the 87Sr/86Sr isotopic ratio mass spectrometry". European Food Research and Technology 242, n.º 9 (31 de maio de 2016): 1411–39. http://dx.doi.org/10.1007/s00217-016-2712-2.

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Teses / dissertações sobre o assunto "86Sr isotopic ratio"

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Kaya, Ayse Deniz. "Unveilling the role of technological processes on the strontium isotopic ratio, fingerprint of wines' geographical origin". Master's thesis, ISA-UL, 2016. http://hdl.handle.net/10400.5/13345.

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Mestrado Vinifera Euromaster - Instituto Superior de Agronomia - UL / Institut National d'Études Supérieurs Agronomiques, Montpellier
Based on the close relationship of strontium isotopic ratio 87Sr/86Sr between soil and plants, this isotopic ratio has been reported as fingerprint tool to verify wine geographical origin and its authenticity In the last decade, some studies suggested that winemaking applications do not alter the 87Sr/86Sr isotopic ratios from vineyard to the wine despite the variations of mineral concentration. However, information about wood impact on 87Sr/86Sr is lacking in the literature. In this study, we investigated the wood ageing effect on 87Sr/86Sr, and also on the multi-elemental compositon of wine, which to our best knowledge are novelties, thus representing important advances to this field of knowledge. A red wine from Castelão grape variety was aged in stainless steel vats (34,000 L) with oak wood staves, in triplicate. The wines were sampled after 30, 60 and 90 days of ageing and evaluated in terms of: 87Sr/86Sr, by Q-ICP-MS after Sr and Rb separation by ion exchange chromatography; multi-elemental analysis (Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, Pb) by Q-ICP-MS; Na, K, Ca, Fe by FAAS. Wood ageingWood ageing effect on total polysaccharides concentration , chromatic characteristics and phenolic composition was also evaluated. Statistical analysis showed that there was no significant difference of the 87Sr/86Sr between the control wine and wine aged with wood. The results show that strontium isotopic ratio of wines was not altered even after ageing with wood (0.710 at initial time and 0.709 after 90 days) despite having a significant increase in Sr concentration by wood stage. This suggests that 87Sr/86Sr might be used as a reliable geographical indicator. Time had significant impact on Al, V, Zn, Ni, Cs, Pb and also on Na, K, Ca and Fe while wood stage only altered concentrations of Mg, V, Co, Ni and Sr. Our study suggests that wood ageing does not impact the 87Sr/86Sr, accordingly it will shed some light for further studies.
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Nasr, Emna. "Signatures inorganiques et isotopiques combinées pour la discrimination de l'origine géographique de l'huile d'olive". Electronic Thesis or Diss., Pau, 2022. http://www.theses.fr/2022PAUU3004.

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La mondialisation de l'industrie alimentaire a suscité l'intérêt des consommateurs pour l'origine géographique et la qualité des produits alimentaires. L'augmentation de la production et de la consommation mondiale de denrées alimentaires a toutefois entraîné la propagation de pratiques frauduleuses. Celles-ci menacent à la fois la santé des consommateurs et l'équilibre économique de l'industrie alimentaire, qui subit chaque année d'énormes pertes financières. L'huile d'olive est l'un des produits alimentaires les plus fraudés. En conséquence, un large éventail de stratégies analytiques a été proposé pour l'authentification géographique de l'huile d'olive. Les approches les plus fiables qui ont démontré des résultats prometteurs pour la traçabilité géographique des produits alimentaires étaient basées sur l'empreinte multi-élémentaire et isotopique. Néanmoins, éléments traces, initialement présents à des concentrations faibles à très faibles dans l'huile d'olive, sont dissous dans une matrice lipidique complexe et donc l'introduction des échantillons dans les instruments basés sur le plasma et les mesures précises des composants chimiques sont difficiles. Cette étude présente une approche analytique fiable basée sur une information géographique tridimensionnelle : (1) la composition minérale du sol à travers l'analyse des éléments traces; (2) le contexte géologique par l'analyse de la composition isotopique du Sr; et (3) le contexte pédo-climatique à travers la détermination des isotopes stables du carbone dans les huiles d'olive. Tout d'abord, les éléments traces ont été quantifiés dans des huiles d'olive de Tunisie, d'Espagne et de France avec une grande précision et exactitude par ICP-MS quadripolaire suivant une procédure analytique optimisée. Les concentrations élémentaires combinées à la chimiométrie ont permis de classer les huiles d'olive en fonction de leur provenance géographique. Par la suite, une méthode innovante a été développée et appliquée avec succès pour l'extraction quantitative du Sr à partir de l'huile d'olive et la mesure précise du rapport isotopique 87Sr/86Sr par MC-ICP-MS. La conservation des rapports isotopiques 87Sr/86Sr pendant le transfert du Sr du sol à la plante et pendant l'extraction de l'huile d'olive a été démontrée. Les résultats ont été corrélés avec les caractéristiques géologiques des roches mères et ont ainsi mis en évidence que la composition isotopique Sr de l'huile d'olive peut être utilisée comme un outil fiable pour identifier la provenance géographique de l'huile d'olive. Dans la dernière partie du manuscrit, les isotopes stables du carbone ont été déterminés dans les huiles d'olive par IRMS et ont permis de retracer les processus physiologiques de l'olivier en fonction des caractéristiques environnementales spécifiques. Chacune des trois approches mono-paramètre étudiées a fourni des informations géographiques fiables mais limitées. C'est pourquoi elles ont été combinées avec la chimiométrie afin d'établir un outil d'authentification géographique avancé capable de faire face aux pratiques frauduleuses les plus sophistiquées
The globalization of the food industry has raised consumer interest in the geographical origin and the quality of food products. The global increase in food production and consumption, however, has led to fraudulent practices spreading. It threatens both the health of consumers and the economic balance of the food industry, which suffers huge financial loss every year. Olive oil is one of the most adulterated food products. As a result, a large array of analytical strategies was proposed for the geographical authentication of olive oil. The most reliable approaches that have demonstrated promising results for the geographical traceability of food products were based on the multi-elemental and isotopic fingerprinting. Nevertheless, trace elements, initially found at low to critically low concentrations in olive oil, are dissolved in a complex lipid matrix and thus the samples introduction in plasma-based instruments and the precise measurements of chemical components are challenging. This study presents a reliable analytical approach based on a three dimensional geographic information: (1) the mineral composition of the soil through the analysis of trace elements; (2) the geological background through the analysis of Sr isotopic composition; and (3) the pedo-climatic context through the determination of stable isotopes of carbon in olive oils. First, the trace elements were quantified in olive oils from Tunisia, Spain and France with high precision and accuracy by quadrupole ICP-MS following an optimized analytical procedure. The elemental concentrations combined with chemometrics allowed to classify olive oils according to their geographical provenance. Subsequently, an innovative method was developed and successfully applied for the quantitative extraction of Sr from olive oil matrix and accurate measurement of 87Sr/86Sr isotopic ratio by MC-ICP-MS. The conservation of 87Sr/86Sr isotopic ratios during the transfer of Sr from the soil to the plant and during olive oil extraction was demonstrated. The results were correlated with the geological characteristics of the bedrocks and thus highlighted that Sr isotopic composition of olive oil can be used as a reliable tool for fingerprinting olive oil geographic provenance. In last part of the manuscript, the stable isotopes of carbon were determined in olive oils by IRMS and allowed to trace the physiological processes of the olive tree to specific environmental characteristics. Each of the three studied single-parameter approaches provided reliable but limited geographic information. Therefore, they were combined together with chemometrics in order to establish an advanced geographical authentication tool able to overcome the most sophisticated fraudulent practices
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Drahotusky-Bruketa, Luka. "Strontium isotope ratio analysis (87Sr/86Sr) in the post-classical population of La Selvicciola (Viterbo, Italy, VI-VIII century CE)". Master's thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/29167.

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Abstract: The Longobard cemetery of La Selvicciola, located in the province of Viterbo, Italy, has been the subject of systematic excavations since 1982. The archaeological artefacts recovered from the cemetery suggest that it was used from the end of the VI century to the beginning of the VIII century CE. To date, the pattern of occupation of the cemetery by the Longobards and the relation between these invading peoples and the earlier roman population is still to be fully assessed. The thesis intends to offer a description of mobility patterns observed in the Longobard burials employing strontium isotope ratio (87Sr/86Sr) measured in human and animal bone and dental enamel. Data obtained are compared with bioarchaeological, geological and historical context. This study aims to understand the cultural identity of individuals, firstly by determining if reconstructed isotopic signatures support the existing historical, archaeological and anthropological information about these skeletons, and secondly by identifying any distinguishable trends between cultural groups which can be linked to status or behavior.
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Warham, Joseph O. "Mapping biosphere strontium isotope ratios across major lithological boundaries. A systematic investigation of the major influences on geographic variation in the 87Sr/86Sr composition of bioavailable strontium above the Cretaceous and Jurassic rocks of England". Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5500.

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Strontium isotope analysis has provided archaeologists with an unprecedented opportunity to study the mobility of humans and animals in the past. However, a lack of systematic environmental baseline data has seriously restricted the full potential of the analytical technique; there is little biosphere data available against which to compare measured skeletal data. This thesis examines the extent to which geographic variation in biosphere 87Sr/86Sr composition can be spatially resolved within the lowland terrain of England, in a geographically and geologically coherent study area. Systematically collected samples of vegetation, stream water and surface soils, including new and archived material have been used. The potential of these sample media to provide reliable estimates of the 87Sr/86Sr composition of bioavailable strontium are evaluated under both high-density and low-density sampling regimes, and against new analyses of local archaeological material. Areas lying south of the Anglian glacial limit, display a pattern of geographic 87Sr/86Sr biosphere variation (0.7080¿0.7105) controlled by solid geology, as demonstrated by high-density biosphere mapping. Data collected at a wider geographic scale, including above superficial deposits, indicate the dominant influence of re-worked local rocks on the biosphere. These methods have enabled a reclassification of the archaeologically important Cretaceous Chalk domain. Analysis of rainwater and other indicators of atmospheric deposition show that, in this setting, local biosphere variation is not significantly perturbed by atmospheric inputs. Time-related data from archaeological cattle and sheep/goat tooth enamel suggest that the modern biosphere data can be used to understand livestock management regimes and that these are more powerful than using an average value from the enamel. A more complete understanding of possible patterns of mobility in a group of humans has been achieved through analysis of material from Winchester and comparison with the Chalk biosphere domain.
British Geological Survey¿s British University Funding Initiative (BUFI) and the School of Life Sciences at the University of Bradford joint funding.
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Warham, Joseph Olav. "Mapping biosphere strontium isotope ratios across major lithological boundaries : a systematic investigation of the major influences on geographic variation in the 87Sr/86Sr composition of bioavailable strontium above the Cretaceous and Jurassic rocks of England". Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5500.

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Strontium isotope analysis has provided archaeologists with an unprecedented opportunity to study the mobility of humans and animals in the past. However, a lack of systematic environmental baseline data has seriously restricted the full potential of the analytical technique; there is little biosphere data available against which to compare measured skeletal data. This thesis examines the extent to which geographic variation in biosphere 87Sr/86Sr composition can be spatially resolved within the lowland terrain of England, in a geographically and geologically coherent study area. Systematically collected samples of vegetation, stream water and surface soils, including new and archived material have been used. The potential of these sample media to provide reliable estimates of the ⁸⁷Sr/⁸⁶Sr composition of bioavailable strontium are evaluated under both high-density and low-density sampling regimes, and against new analyses of local archaeological material. Areas lying south of the Anglian glacial limit, display a pattern of geographic ⁸⁷Sr/⁸⁶Sr biosphere variation (0.7080-0.7105) controlled by solid geology, as demonstrated by high-density biosphere mapping. Data collected at a wider geographic scale, including above superficial deposits, indicate the dominant influence of re-worked local rocks on the biosphere. These methods have enabled a reclassification of the archaeologically important Cretaceous Chalk domain. Analysis of rainwater and other indicators of atmospheric deposition show that, in this setting, local biosphere variation is not significantly perturbed by atmospheric inputs. Time-related data from archaeological cattle and sheep/goat tooth enamel suggest that the modern biosphere data can be used to understand livestock management regimes and that these are more powerful than using an average value from the enamel. A more complete understanding of possible patterns of mobility in a group of humans has been achieved through analysis of material from Winchester and comparison with the Chalk biosphere domain.
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Vorster, Clarisa. "Precise 87Sr/86Sr isotope ratio measurement by quadrupole based ICP-MS after ion exchange separation of Rb for provenance determination of agricultural products". Thesis, 2010. http://hdl.handle.net/10210/3158.

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M.Sc.
The strontium isotope ratio 87Sr/86Sr in the wine and soil of four wine-producing regions in South Africa has been determined using quadrupole ICP-MS. Isotope ratio measurements with fairly good precision had been obtained and 87Sr/86Sr ratio values in wine and soil samples were statistically evaluated to determine whether the regions investigated could be distinguished. Statistical interpretation of data revealed that the Robertson wine-producing region could be distinguished from Stellenbosch, Swartland and Walker Bay wine regions on the basis of their 87Sr/86Sr ratio. By using a combination of 87Sr/86Sr and multielement data, canonical discriminant functions with very good classification abilities could be obtained to correctly distinguish between wine and soil samples originating from a specific production region. Due to the isobaric overlap of strontium and rubidium at mass 87, a very good strontium-rubidium separation method had to be developed. The chelating properties of EDTA and DCTA in combination with ion exchange chromatography were explored in order to achieve such a separation. Due to the advanced rubidium separation ability of the developed DCTA elution method, it has been employed in all wine and soil sample preparations. Since chromatographic ion exchange procedures are not capable of removing all the rubidium from the sample matrices, 87Sr/86Sr ratio values were mathematically corrected for residual rubidium using an 88Sr correction. Since strontium isotope ratio measurements require very good precision, it is traditionally determined using TIMS. However, due to the ease of operation, shorter analysis time and widespread availability of quadrupole ICP-MS, the technique was evaluated for its merit for determining strontium isotope ratios. The optimization of acquisition parameters for the determination of the 87Sr/86Sr ratio in wine and soil samples with good precision of below 0.1% RSD has been conducted. Furthermore, selected sample matrix components were assessed as possible matrix interferences as well as for their ability to affect the precision of measurements. It was concluded that with adequate optimization of acquisition parameters, proper sample preparation and reliable mathematical correction of data, 87Sr/86Sr ratio measurements with reasonable precision could be obtained using quadrupole ICP-MS.
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Capítulos de livros sobre o assunto "86Sr isotopic ratio"

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Burton, James H., e Rachel Hahn. "Assessing the “Local” 87Sr/86Sr Ratio for Humans". In Isotopic Landscapes in Bioarchaeology, 113–21. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-48339-8_6.

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Söllner, Frank, Anita Toncala, Stefan Hölzl e Gisela Grupe. "Determination of Geo-dependent Bioavailable 87Sr/86Sr Isotopic Ratios for Archaeological Sites from the Inn Valley (Austria): A Model Calculation". In Isotopic Landscapes in Bioarchaeology, 123–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-48339-8_7.

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Graustein, W. C. "87Sr/86Sr Ratios Measure the Sources and Flow of Strontium in Terrestrial Ecosystems". In Stable Isotopes in Ecological Research, 491–512. New York, NY: Springer New York, 1989. http://dx.doi.org/10.1007/978-1-4612-3498-2_28.

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Bełka, Zdzisław. "Proweniencja ludności pochowanej na cmentarzysku oraz form odlewniczych z późnej epoki brązu na podstawie analizy izotopów strontu i neodymu / Provenance of the individuals buried at the Late Bronze Age cemetery and of the casting moulds in light of analyses of strontium and neodymium isotopes". In Gogolin-Strzebniów, stanowisko 12. Cmentarzysko kultury łużyckiej na Wyżynie Śląskiej, 125–30. Wydawnictwo i Pracownia Archeologiczna Profil-Archeo, 2021. http://dx.doi.org/10.33547/oda-sah.11.gog.10.

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Strontium isotope ratios (87Sr/86Sr) were applied to investigate provenance of the Bronze Age population buried at cemetery in Gogolin-Strzebniów. The study used 12 samples: two human enamel samples from inhumation graves and ten samples of petrous part of temporal bone from cremation burials. Baseline information on the local Sr isotope composition was established on geological data. The human samples of ten individuals yielded a quite narrow range of Sr isotope signatures, from 0.7112 to 0.7121 (Table 1; Fig. 1). The obtained results indicate that these individuals have 87Sr/86Sr values which fits well within the range of Sr isotope signatures established for the local area. Signatures of two individuals are outside this range. The bone remains from grave 59 have a lower value of 87Sr/86Sr (0.7107), and a molar tooth of an individual from grave 63 – has a higher value (0.7128). These two individuals have been recognized as non-local. Moreover, the isotopic composition of neodymium (143Nd/144Nd) was analysed for three casting moulds found in grave 24 (Fig. 2; Table 2). The isotopes of this element are the best indicators of the origin of rocks, sediments and related materials (e.g. ceramics) so they allow not only for estimation of the geographical origin of samples, but also for determining their geological age. Because of these advantages, neodymium isotopes are the most frequently used indicator of provenance in geological research. In this method, we obtain several parameters (ratio 143Nd/144Nd, neodymium epsilon eNd, ratio 147Sm/144Nd, value of the model age TDM) for each analysed sample, which together allow for a very precise identification of the raw material origin. Mould No. 8 is made of clay. This material is characterised by an epsilon value of -12.3 and the value of model age TDM = 1.77 Ga, indicating the possibility of the local origin of the material used for the production of this tool. Mould No. 1 is made of sandstone with a model age value TDM = 2.06 Ga. In Europe, such high TDM values are associated with rocks of the East European Platform, which covers the area of Scandinavia (without Denmark), Russia, Ukraine and north-eastern Poland. During the spread of the Scandinavian ice sheet during the Pleistocene period, erratic “Scandinavian” material was transported to Central Europe. In Poland, post-glacial sediments, often containing various erratics, are common in the area of nearly 90% of the territory. Therefore, it is very likely that the sandstone used to produce mould No. 1 was obtained from local Scandinavian materials. Mould No. 3 was made of sandstone, which has similar values of eNd and a similar 143Nd/144Nd ratio as mould No. 1. It cannot therefore be ruled out that this sandstone is also derived from the Scandinavian materials. However, a fully reliable interpretation of this artefact is impossible, because the rock has an unnaturally low of 147Sm/144Nd ratio and therefore its model age is also low (TDM = 1.25). Although rocks of this model age are known from other areas of the world, in Europe they are found only in Scotland. Therefore, it is very probable that the low ratio of 147Sm/144Nd is the result of the secondary removal of the samarium from this rock, most likely during the interaction with hot metal (bronze).
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Zheng, Y., P. N. Froelich, M. E. Torres e A. N. Dia. "Stable Isotopes (18O/16O) and 87Sr/86Sr Ratios in Pore Fluids of the Chile Triple Junction Accretionary Prism: Implications for Diagenesis and Fluid Migration". In Proceedings of the Ocean Drilling Program, 141 Scientific Results. Ocean Drilling Program, 1995. http://dx.doi.org/10.2973/odp.proc.sr.141.025.1995.

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Trabalhos de conferências sobre o assunto "86Sr isotopic ratio"

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Chernykh, A. V., A. N. Pyrayev e F. F. Dultsev. "NEW DATA ON THE ISOTOPIC COMPOSITION OF BRINES OF OIL AND GAS DEPOSITS OF THE SIBERIAN PLATFORM". In All-Russian Youth Scientific Conference with the Participation of Foreign Scientists Trofimuk Readings - 2021. Novosibirsk State University, 2021. http://dx.doi.org/10.25205/978-5-4437-1251-2-121-125.

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The new isotope-geochemical data on the Siberian platform supersaturated brines of a wide stratigraphic range (from Riphean to Ordovician) are presented. There is a wide range of oxygen and hydrogen stable isotope composition in the studied brines: from –133 to –17,5 % for δD and from –17,0 to –2,5 % for δ18O. The δD and δ18O values point on the sedimentation-metamorphic genesis of the brines. The carbon isotope composition of the DIC in brines range from –31 to +12,7 %. It is supposed that DIC has the biogenic (bacterial) origin. The youngest brine DIC has the heaviest carbon isotope composition whereas the oldest brine DIC has the biggest concentration of 12C. The strontium ratios of the studied brines divide them into two groups: with 87Sr/86Sr ratios, close to those of the modern ocean waters, and brines with 87Sr/86Sr values significantly exceeding modern ocean strontium ratios. It is assumed that the burial of the brines of the second group took place in the presence of clastic material of the continental crust, with a high content of radioactive 87Rb.
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Castro, Ian O., Brooke E. Crowley, Steven M. Goodman e Alaina C. Strand. "DOES VEGETATION REMOVAL INFLUENCE BIOAVAILABLE STRONTIUM ISOTOPE RATIOS (87SR/86SR)?" In 50th Annual GSA North-Central Section Meeting. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016nc-275124.

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Talovina, Irina. "ISOTOPE RATIO 87SR/86SR IN NICKEL ORE OF THE URALIAN SUPERGENE DEPOSITS AND THEIR GENESIS". In 17th International Multidisciplinary Scientific GeoConference SGEM2017. Stef92 Technology, 2017. http://dx.doi.org/10.5593/sgem2017/11/s01.035.

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Kasyanova, A. V., M. V. Streletskaya, M. V. Chervyakovskaya e D. V. Kiseleva. "A method for 87Sr/86Sr isotope ratio determination in biogenic apatite by MC-ICP-MS using the SSB technique". In PHYSICS, TECHNOLOGIES AND INNOVATION (PTI-2019): Proceedings of the VI International Young Researchers’ Conference. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5134179.

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Ma, Lin, Sandra Garcia, Pascale Louvat e Jerome Gaillardet. "COMBINING URANIUM, BORON, AND STRONTIUM ISOTOPE RATIOS (234U/238U, δ11B, 87SR/86SR) TO TRACE SALINITY SOURCES IN THE SEMI-ARID RIO GRANDE RIVER OF SOUTHWESTERN UNITED STATES". In GSA Annual Meeting in Phoenix, Arizona, USA - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019am-334320.

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