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1.
An Iberian archaeological site located in the east of Spain is one of the most important cupellation centers found in the 4th century b.c. Different metallurgical materials were found in the archaeological site as minerals, cast slags, forged slags, metallic lead, cupella fragments and bronzes. Also was found reverbs remains used for cupper-based materials and cupellation procedure, and hearth forge remains for obtained iron material. The recuperated samples were studied by comparing samples of the same type of material by macroanalysis and microanalysis. The microanalysis and quantitation of the different archaeological materials was carried out by SEM/EDX. The information provides about the knowledge of a metallurgic process such as that of silver production by lead cupellation. The microanalysis results reflect the variety of elements that constitute the slags and other materials, and that come from the forge of the worked metallic materials. Also, the process cupellation was confirmed by the identification of lead and silver. The presence of forge slag corroborates the use of the great amount of recovered heart forges in the excavation like metallurgical structures for the iron work.  相似文献   

2.
Rungia congoensis, a traditional vegetable from Kongo Central area (DR. Congo) was studied for establishing microscopic characters and characterised by chromatographic techniques and their in vitro biochemical activities against ROS production were evaluated in cellular models and on an enzyme, myeloperoxidase (MPO), involved in inflammation. Microscopically leaf can be characterised by non-glandular and glandular trichomes, sinuous anticlinal epidermal cells, diacytic stomata and helical vessels. Methanolic extract displayed high cellular antioxidant activity at the concentrations range of 0.1–10 μg mL?1 and 1–20 μg mL?1 using lucigenin on neutrophils and DCFH-DA on HL 60, respectively. This extract also showed, more efficient effects on extracellular and intracellular ROS production and MPO activity. Antioxidant and anti-inflammatory activities of R. congoensis were significantly higher, positively correlated with their phytochemical constituents such as flavonoids, iridoids and phenolic acids; and could justify their use as traditional vegetable and potent local nutraceutical resource.  相似文献   

3.
This work reports results from a chemico-physical study of the stained glass window of the southern transept of St. Anthony's Basilica (Padova, Italy), dated to the late 19th century AD. Selected samples of glass with or without grisailles were characterised by means of various X-ray spectrometric techniques, such as wavelength dispersive X-ray fluorescence, electron microprobe, and scanning electron microscopy with energy dispersive X-ray microanalysis, coupled, in some cases, with X-ray powder diffraction. Integration of analytical results revealed many types of glass related to different phases of the “life” of stained glass, and the production technology of grisailles. In addition, the degree of damage undergone throughout the last century due to materials used in the production of windows was studied, to design and optimise a combined conservation and restoration strategy. Lastly, another important aim of the present study was to amplify the database on 19th-century stained glass windows, little documented in the literature.  相似文献   

4.
Inks and paper are the main materials and components of library and archive collections. Since the Third century B.C. there has been a continual succession of ink recipes from all over the world, with varying levels of documentation of the recipes used; however, it was only in the 19th century that Europe became the main producer and industrial leader in the discovery of new products. The aim of this study is to find out more about this last historical period, when new inks were created that had never been known or used in the past. In this study we chose four inks: they belong to documents preserved in the archive of the Superintendence Beni architettonici per il paesaggio e per il patrimonio storico artistico ed etnoantropologico (BAPPDAD) of Venice Lagoon, held in the Palazzo Ducale (Ducal Palace) of Venice.Fourier Transform Infrared Spectroscopy (ATR), Scanning Electron Microscopy (SEM-EDS) and pyrolysis coupled to a gas chromatograph with mass spectrometric detector (Py–GC–MS) allowed us to obtain a qualitative characterization of organic and inorganic elements in three different ink typologies.  相似文献   

5.
The present work is a continuation of a research study performed at our laboratory aiming at the multielement analysis of rock samples (basalts and shale) by inductively coupled plasma mass spectrometry in combination with laser ablation using borate glasses as analytical targets. Argon, nitrogen-argon mixtures and helium were evaluated as cell gases, the latter confirming its better performance. Different operational parameters of the laser, such as gas flow, energy, focus, scanning speed and sampling frequency were optimized. External calibration was made with standards prepared by fusion of geological reference materials (basalts 688 and BCR-2, obsidian SRM 278, and shale SGR-1) of different mass fractions in the meta-tetra borate matrix. Coefficients of determination (R2) were > 0.99 for 30 elements from o total of 40 determined. Method validation was then performed using additional certified reference materials (BHVO-2, BIR-1, SCo-1) produced as borate targets in a similar way. Accuracies were better than 10% for most of the elements studied and analytical precisions, calculated from the residual standard deviations of calibration curves were, typically, between 6% and 10%. Additionally, the semiquantitative TotalQuant® technique was applied, which gave, within the expected uncertainty for this calibration technique, concordant results when compared to the quantitative external calibration procedure. Both methods were then used for the analysis of marine shale samples, which are of great geological interest in petroleum prospecting.  相似文献   

6.
Analytical investigations using Scanning Electron Microscopy (SEM), with Energy Dispersive Spectrometry (EDS), X-ray Diffraction (XRD), Infrared Spectroscopy (FT-IR) and High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (CP-MAS NMR), were carried out on white, yellow and red overpaintings on Apulian red-figured pottery fragments (4th century BC) from Altamura, Monte Sannace and Canosa - among the most relevant archaeological sites in ancient Peucetia - in order to outline technological features and define the nature of pigments. The results obtained allow us to highlight that Apulian objects have an external appearance which is very similar to Attic objects, but that they are nevertheless different, as they were made using locally available raw materials employing similar but not identical production technology. Perhaps familiarity, rather than real and proper continuity with the Attic pottery tradition, would explain the analytical results.Moreover, this paper proves that solid state nuclear magnetic spectroscopy (CP-MAS NMR) is a useful analytical tool for the examination of ancient pottery, which is also suitable for the identification of its firing temperature.  相似文献   

7.
The reaction of copper(II) acetate or fluoride with classic dioximes in the presence of 1,2-bis(4-pyridyl)ethane resulted in four novel compounds with the compositions [Cu2(dmgH)4bpe] (1), [Cu2(NioxH)4bpe] (2), [Cu2(dpgH)4bpe] (3), and [Cu2(dpgH)4bpe][Cu(dpgH)2bpe]2·2DMF (4) (where dmgH2 = dimethylglyoxime, NioxH2 = 1,2-cyclohexanedionedioxime, dpgH2 = diphenylglyoxime, bpe = 1,2-bis(4-pyridyl)ethane, and DMF = N,N′-dimethylformamide), whose crystal structures were determined by single crystal X-ray diffraction. In the binuclear molecules 1-3, as well as in both binuclear and mononuclear molecules in 4 each Cu(II) atom has an identical N5-environment formulated by four oximic nitrogen atoms of two monodeprotonated ligands in a slightly distorted square planar mode, and the nitrogen atom of the bpe molecule being in the apical position. The new compounds were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Luminescence investigations for 1, 2 and 4 were carried out to clarify whether the guest inclusion in the crystal lattice is accompanied by changes in the emission spectra.  相似文献   

8.
An exceptional mineral specimen, particularly interesting for collectors and researchers, is “watermelon” tourmaline, mined in the Paprok region in Nuristan, Afghanistan. A pale pink core (zone III) is surrounded by a thin, colorless zone (zone II), and a green outer zone (zone I). Differences between zones are clearly seen in the SEM picture, i.e., diversity in the size of constituent forms, and also the presence of inclusions of alien mineral phases which range from a few dozen to a few μm. In the line mapping experiment the Raman spectra were collected from the inner core towards the outer rim. There are observed typical for tourmaline (elbaite) groups of bands: at ca. 3600, 1100, 700, 400 and 250 cm−1. Raman measurements determine the differences in the local chemical composition of particular zones. Interestingly, there is a new band emerging in the outer zone at ca. 840 cm−1, and it could be due to the SiO4 stretching vibrational modes predisposed by the Fe ion presence in the mineral. The organic inclusions are present in the whole volume of the investigated gem. Organic inclusion content appears to be versatile. Raman spectra confirm the presence of hydrogen sulphide (2610 cm−1), methane (2912 cm−1), ethane (2950 cm−1), and propane (2895 cm−1). In the corresponding bending vibrations region apart from CH2, CH3 vibrations and C–O stretching (CO2) at (1280, 1390 cm−1), characteristic bands are also observed at ca. 1340, 1600 and 1660 cm−1. The last ones possibly mark the evolution of graphitization process occurring from fluid saturated inclusions within condensed ring aromatics (1660 cm−1 band), towards slightly more organized, although still amorphous forms of carbonaceous matter (1340 and 1600 cm−1).  相似文献   

9.
Butyltin (tributyltin TBT; dibutyltin DBT and monobutyltin MBT) speciation was measured in the liver of beluga whales from the St Lawrence Estuary and Hudson Strait (northern Quebec). Using GC–MS, liver samples were analysed from 21 beluga whales found dead, stranded along the shores of the St Lawrence during the period 1995–1998. In all cases, including a neonate specimen, the liver was contaminated with butyltin compounds with concentrations in the range 0.04–2.1 mg Sn kg−1 on a dry weight basis. Liver samples of five beluga whales from Hudson Strait obtained in the summer of 1998 were also analysed. For these animals, hepatic butyltin concentrations were consistently below the detection limit (<0.5 ng Sn g−1 for MBT and <0.2 ng Sn g−1 for DBT and TBT). Compared with published data on the contamination by TBT of the marine mammals of the St Lawrence in 1988, these contemporary results clearly indicate that the level of contamination of the beluga whales in this coastal marine ecosystem has not decreased ten years after regulating the use of TBT‐based antifoulants on small craft. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

10.
Thirty-eight samples of pottery were analyzed for determining chemical composition in order to establish their provenance. The potteries tested in the present research come from Himera and Pestavecchia archaeological sites. After digestion in microwave oven, the samples have been analyzed for fourteen minor elements (Ba, Cd, Co, Cr, Cu, Ga, Li, Mn, Ni, Pb, Sr, Ti, Tl, and Zn) and six major elements (Al, Ca, Fe, K, Mg, and Na). Chemical analysis was carried out by Inductively Coupled Plasma–Optical Emission Spectroscopy (ICP–OES). The most abundant minor elements are Cr, Ba and Ni. Cr concentration ranged from 66 to 3635 mg kg− 1, Ba concentration ranged from 388 to 2677 mg kg− 1 and Ni concentration ranged from 35 to 1758 mg kg− 1. The relative standard deviation (RSD) of the replicates on the concentrations of analyzed metals ranged from 0.07% to 14%.The aim of this study is to assign the local or non-local provenance of the examined potteries, in particular validating and clarifying archaeological hypothesis based on the simple visual examination and stylistic characterization of ceramic objects. Principal component analysis performed on the dataset, together with the application of cluster technique and non statistical analysis, allowed the identification of three main groups of samples and a lonely one (R 97). In particular, sample R 97 shows high Cr concentration (3635 mg kg− 1) and high Ni concentration (1758 mg kg− 1), typical of Corinthian pottery. The results of chemical analysis show that the stylistic features are not always sufficient to correctly identify the origin of a ceramic object.  相似文献   

11.
The acid-base behaviour of adenine, adenosine 3′,5′-cyclic monophosphate and poly(adenylic) acid was studied at 37 °C by spectrometric titration in acetonitrile-water mixtures. Hard-modelling and soft-modelling approaches were used for this purpose. The first one, which requires the assumption of a previous chemical model, was used for the study of monomeric compounds and the second one, an alternating least-squares multivariate curve resolution procedure, was used for the study of poly(adenylic) acid, because it does not require any previous chemical model. The pKa values were correlated with either macroscopic or microscopic parameters, such as solvatochromic parameters. The influence of solvent composition on the intramolecular and solute/solvent interactions such as base stacking and hydrogen-bonding, affects the structure, solubility and the number of species detected.  相似文献   

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Bis(dimethylstibanyl)oxane ( 1 ) and ‐sulfane ( 2 ), the two simplest organoelement species with an Sb–E–Sb fragment (E = O, S), were prepared by alkaline hydrolysis of bromodimethylstibane and by oxidation of tetramethyldistibane with sulfur [18], respectively. As shown by an x‐ray structure analysis of compound 1 (m. p. < –20 °C; P212121, a = 675.9(2), b = 803.1(2), c = 1666.8(4) pm at –70 ± 2 °C; Z = 4; R1 = 0.042), the molecules (O–Sb 198.8 and 209.9 pm, Sb–O–Sb 123.0°) adopt a syn‐anti conformation in the solid state and are arranged in zigzag chains along [010] via weak intermolecular O‥Sb interactions (258.5 pm, Sb–O‥Sb 117.8°, O‥Sb–O 173.5°) making use, however, of only one Me2Sb moiety. Primary and secondary bond lengths and angles agree very well with corresponding values published for valentinite, the orthorhombic modification of antimony(III) oxide [3]. Bis(dimethylstibanyl)sulfane ( 2 ) (m. p. 29 to 31 °C) crystallizes in the uncommon space group P6522 (a = 927.8(3), c = 1940.9(7) pm at –100 ± 2 °C; Z = 6; R1 = 0.021). Owing to coordination numbers of (1 + 1) and (2 + 2) for both Me2Sb groups and the sulfur atom, respectively, molecules with an approximate syn‐syn conformation (S–Sb 249.8 pm, Sb–S–Sb 92.35°) build up a three‐dimensional net of double helices which are linked together by Sb‥S contacts (316.4 pm). These parameters shed more light onto the rather complicated structure and bonding situation in stibnite (antimony(III) sulfide [4]). The molecular packing of compound 2 is compared with the structures of relevant inorganic solids, especially with that of β‐quartz [37].  相似文献   

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