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Abstract  

A procedure is demonstrated, through a simulation study, for the determination of the origin of unknown spent nuclear fuel, an important and challenging task in nuclear forensics. The procedure is an isotopic fingerprinting method relying on the fission product content of the unknown. The ‘unknown’ nuclear material is represented by the spent nuclear fuel of known origin in order to demonstrate the method and verify its predictive capabilities. The method is based on the comparison of the fission product compositions of the ‘unknown’ material and simulated known spent fuels from a range of commercial nuclear power stations using the multivariate statistical technique of factor analysis. Then, the provenance of the ‘unknown’ spent fuel is the commercial fuel with which it exhibits the highest similarity with respect to the fission product content.

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Summary  

Sixteen pumice samples produced by the youngest eruption sequences of Mt. Pelato (Island of Lipari, Italy) were analyzed with instrumental neutron activation analysis (INAA) for their major and trace element contents, in particular Al, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sm, Ta, Tb, Th, Ti, U, V, Yb, Zn, and Zr. A pumice from the archaeological excavation in Tel Megadim, Israel, could be correlated to this volcanic source, using its chemical fingerprint. This result, together with the background information about the well dated eruption cycles of this volcano, lead to the assumption that trade connections existed between cultures in Palestine and the Tyrrhenian region during the Persian Period (approx. between the 6th and 3rd century B.C.), in spite of the long distance of over 2000 km.

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Jayarao, B. M., Gillespie, B. E. and Oliver, S. P. (1998): Application of randomly amplified polymorphic DNA fingerprinting for species identification of bacteria isolated from bovine milk. Journal of Food

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Abstract  

The TG, DTG and DSC methods were used for investigation of the thermo-oxidative degradation in static air atmosphere and oxygen flow of some sorts of lime tree wood (recent lime tree woods with different preparations, old lime tree woods extracted from some Romanian historical and/or cultural objects). At the progressive heating in the mentioned atmospheres, all the investigated materials exhibit three successive processes, associated with dehydration and two complex thermo-oxidative processes. Each analyzed material has a characteristic thermogram (TG, DTG and/or DSC curve) that can be considered a material “fingerprint”. It was pointed out that the following non-isothermal parameters can be used for distinction between a new and old lime tree wood: mass loss in the first process of thermo-oxidation, ratio between the mass losses in the first and the second processes of thermo-oxidation, the maximum rate of the first process of thermo-oxidation. Consequently, the certification of a patrimonial object manufactured from lime tree wood could be performed by applying the thermal analysis methods.

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Abstract  

The thermal analysis methods (TG, DTG and DTA) were used for the investigation of the thermal degradation of some recent manufactured tanned leathers, leathers that are supports of cultural or historical objects (leather from book covers (XVII-XIX centuries); leather from an Austrian belt (Franz Joseph period), Cordoba leather (XVII century), lining leathers), recent and patrimonial parchments and recent extracted collagen (sorts of collagen obtained from bovine leather at different pH-values, bovine collagen with different hydration degree). At progressive heating, all investigated materials exhibit two main successive processes, associated with the dehydration and thermo-oxidative degradation. Each analyzed material has a characteristic thermal analysis curve (TG, DTG and DTA) that can be considered a material 'fingerprint'. This result suggests the use of the thermal analysis methods to identify of leathers from which the patrimonial objects are manufactured. The rate of thermo-oxidation of recent manufactured tanned leathers is substantially higher than the rate of the same process corresponding to naturally aged leathers that exhibit values of the thermo-oxidation rate appropriate to those obtained for parchments and collagens. The rate of thermo-oxidation of leather can thus be used as a criterion to distinguish between recent manufactured leather and patrimonial one.

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Abstract  

Part of a research program on cultural heritage aimed to elucidate the production of ceramic artifacts in Roman Pavia is devoted to the localization of the possible sources of raw materials (claypits) as well as to the technological production processes. Clay samples were collected in two different areas nearby Pavia, Lomellina and Oltrepo. Some of these samples were also fired at 950 °C. Archaeological ceramic samples, mostly bricks and tiles of Roman age, were obtained from excavations of Roman settlings close to Pavia. All samples were submitted to instrumental neutron activation analysis for the determination of Ca, Fe and a number of trace elements. Results indicate (1) fired and raw clay samples keep the same elemental fingerprint so that only raw samples data can be used in archaeometric studies; (2) some parameters based on rare earth elements are useful to discriminate the clay samples from the two investigated areas; (3) clay discrimination is confirmed also by discriminant analysis; and (4) the insertion of the elemental composition data of the ceramic artifacts in the statistical treatment allows one to assign the artifacts to one of the investigated areas and confirms that, at Roman times, the production of ceramic building materials was mostly based on the use of local prime matter.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Yinsong Wang, Aiguo Li, Yuanxun Zhan, Lun Wei, Yan Li, Guilin Zhang, Yaning Xie, Jing Zhang, Yuanmao Zhang, and Zuci Shan

Abstract  

The atmospheric particulate matter samples were collected in Shanghai, China. The X-ray absorption near-edge structure (XANES) spectra of Cr, Mn, Cu and Zn were measured. The XANES spectroscopy was used as a fingerprint to compare with that of reference materials to obtain speciation information. The oxidation state of these elements and main chemical components in the samples were described using the method. The results show that in our samples the oxidation state of Cr is trivalent, Mn mainly exists in the divalent state, Cu also exists in the divalent state, and Zn mainly exists in the zinc sulfate. For the XANES spectra of samples with different particle size and from different sampling site, we did not find their obvious differences. When we compared the XANES spectra of our samples with those of standard reference material SRM 1648, we found that they are similar in regards to the determined elements. The elemental concentrations in the samples were determined by proton induced X-ray emission (PIXE). The difference of elemental concentrations was observed in the different samples.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Andreza Ribeiro, Ana Figueiredo, Regina Ticianelli, Georges Nammoura-Neto, Natália Silva, Mauricio Kakazu, and Guilherme Zahn

Abstract  

São Paulo is the largest city in Brazil and South America with about 20 million inhabitants in the metropolitan area, more than nine million motor vehicles and intense industrial activity, which are responsible for increasing pollution in the region. Nevertheless, little is known concerning metal and semi-metal content in the soils of this metropolitan region. This type of information could be extremely useful as a fingerprint of environmental pollution. The present study determined the elements As, Ba, Co, Cr, Sb, and Zn concentrations in soils adjacent to avenues of highly dense traffic in São Paulo city to assess their levels and possible sources. The analytical technique employed was Instrumental neutron activation analysis. The results showed, except for Co, concentration levels higher than the reference values for soils of São Paulo, according to the Environmental Protection Agency of the State of São Paulo guidelines. When compared to similar studies in other cities around the world, São Paulo soils presented higher levels, probably due to its high density traffic and industrial activity. The concentrations obtained for As and Cr indicate anthropogenic origin. The high levels of the traffic-related elements Ba, Sb, and Zn in soils nearby high density traffic avenues indicate they may originate from vehicular exhausts.

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The leaves of Hibiscus sabdariffa L. are one of the sources of food and traditional medicine. A combination of high-performance thin-layer chromatography (HPTLC) bioautographic assay with mass spectrometry (MS) has been performed to screen and identify the antioxidant compounds in the leaves of H. sabdariffa L. The crude extract of H. sabdariffa L. was separated on silica gel 60 HPTLC plates in an automatic developing chamber (ADC2) with toluene–ethyl acetate–formic acid–methanol (6:6:1.6:1, v/v) as the mobile phase. Antioxidant bands were visualized by dipping in 2,2-diphenyl-1-picrylhydrazyl (DPPH) reagent. Five antioxidant compounds were identified as neochlorogenic acid (1), chlorogenic acid (2), cryptochlorogenic acid (3), rutin (4), and isoquercitrin (5), which could be the predominant contributors to the antioxidant activity of the leaves of H. sabdariffa L. Furthermore, principal component analysis (PCA) was carried out to discriminate ten accessions of H. sabdariffa L. using an image-processing software. This simple HPTLC fingerprint assisted by PCA can be used as a reliable method for the discrimination of different accessions of H. sabdariffa L.

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Progress in plant molecular tools has been resulted in the development of gene-targeted and functional marker systems. CAAT box region is a different pattern of nucleotides with a consensus sequence, GGCCAATCT, which situated upstream of the start codon of eukaryote genes and plays an important role during transcription. In the present study, several CAAT box-derived polymorphism (CBDP) primers were used for fingerprinting in mini-core collection of durum wheat (including internationally developed breeding lines and Iranian landraces). Twelve selected primers amplified 98 loci, of which all were polymorphic. The average values of the polymorphism information content (PIC) and resolving power (Rp) were 0.31 and 9.16, respectively, indicating a high level of variability among studied genotypes. Analysis of molecular variance (AMOVA) indicated that 92% of the total variation resided among populations. The values of the percentage polymorphic bands (PPL), the observed (Na) and effective (Ne) number of alleles, Nei’s gene diversity (He) and Shannon’s information index (I) for Iranian landraces were higher than the breeding lines. The Fandendrogram obtained by cluster analysis grouped all individuals into three main clusters. Our results showed a remarkable level of genetic diversity among studied durum wheat, especially among Iranian landraces, which can be interest for future breeding programs. More importantly, the present study also revealed that CBDP technique was efficient and powerful tool to assess genetic diversity in wheat germplasm. Hence, this technique could be employed individually or in combination with other molecular markers to evaluate genetic diversity and relations among different species.

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