Study of fossil bones by synchrotron radiation micro-spectroscopic techniques and scanning electron microscopy

2013 ◽  
Vol 21 (1) ◽  
pp. 149-160 ◽  
Author(s):  
I. M. Zougrou ◽  
M. Katsikini ◽  
F. Pinakidou ◽  
E. C. Paloura ◽  
L. Papadopoulou ◽  
...  

Earlymost Villafranchian fossil bones of an artiodactyl and a perissodactyl from the Milia excavation site in Grevena, Greece, were studied in order to evaluate diagenetic effects. Optical microscopy revealed the different bone types (fibro-lamellar and Haversian, respectively) of the two fragments and their good preservation state. The spatial distribution of bone apatite and soil-originating elements was studied using micro-X-ray fluorescence (µ-XRF) mapping and scanning electron microscopy. The approximate value of the Ca/P ratio was 2.2, as determined from scanning electron microscopy measurements. Bacterial boring was detected close to the periosteal region and Fe bearing oxides were found to fill bone cavities,e.g.Haversian canals and osteocyte lacunae. In the perissodactyl bone considerable amounts of Mn were detected close to cracks (the Mn/Fe weight ratio takes values up to 3.5). Goethite and pyrite were detected in both samples by means of metallographic microscopy. The local Ca/P ratio determined with µ-XRF varied significantly in metal-poor spots indicating spatial inhomogeneities in the ionic substitutions. XRF line scans that span the bone cross sections revealed that Fe and Mn contaminate the bones from both the periosteum and medullar cavity and aggregate around local maxima. The formation of goethite, irrespective of the local Fe concentration, was verified by the FeK-edge X-ray absorption fine structure (XAFS) spectra. Finally, SrK-edge extended XAFS (EXAFS) revealed that Sr substitutes for Ca in bone apatite without obvious preference to the Ca1or Ca2unit-cell site occupation.

2018 ◽  
Vol 21 (7) ◽  
pp. 495-500 ◽  
Author(s):  
Hassan A. Almarshad ◽  
Sayed M. Badawy ◽  
Abdalkarem F. Alsharari

Aim and Objective: Formation of the gallbladder stones is a common disease and a major health problem. The present study aimed to identify the structures of the most common types of gallbladder stones using X-ray spectroscopic techniques, which provide information about the process of stone formation. Material and Method: Phase and elemental compositions of pure cholesterol and mixed gallstones removed from gallbladders of patients were studied using energy-dispersive X-ray spectroscopy combined with scanning electron microscopy analysis and X-ray diffraction. Results: The crystal structures of gallstones which coincide with standard patterns were confirmed by X-ray diffraction. Plate-like cholesterol crystals with laminar shaped and thin layered structures were clearly observed for gallstone of pure cholesterol by scanning electron microscopy; it also revealed different morphologies from mixed cholesterol stones. Elemental analysis of pure cholesterol and mixed gallstones using energy-dispersive X-ray spectroscopy confirmed the different formation processes of the different types of gallstones. Conclusion: The method of fast and reliable X-ray spectroscopic techniques has numerous advantages over the traditional chemical analysis and other analytical techniques. The results also revealed that the X-ray spectroscopy technique is a promising technique that can aid in understanding the pathogenesis of gallstone disease.


2014 ◽  
Vol 20 (5) ◽  
pp. 1534-1543 ◽  
Author(s):  
Annalaura Restivo ◽  
Ilaria Degano ◽  
Erika Ribechini ◽  
Josefina Pérez-Arantegui ◽  
Maria Perla Colombini

Abstract:An innovative approach, combining field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy (EDX) analysis, is presented to investigate the degradation mechanisms affecting tannin-dyed wool. In fact, tannin-dyed textiles are more sensitive to degradation then those dyed with other dyestuffs, even in the same conservation conditions.FESEM-EDX was first used to study a set of 48 wool specimens (artificially aged) dyed with several raw materials and mordants, and prepared according to historical dyeing recipes. EDX analysis was performed on the surface of wool threads and on their cross-sections. In addition, in order to validate the model formulated by the analysis of reference materials, several samples collected from historical and archaeological textiles were subjected to FESEM-EDX analysis.FESEM-EDX investigations enabled us to reveal the correlation between elemental composition and morphological changes. In addition, aging processes were clarified by studying changes in the elemental composition of wool from the protective cuticle to the fiber core in cross-sections. Morphological and elemental analysis of wool specimens and of archaeological and historical textiles showed that the presence of tannins increases wool damage, primarily by causing a sulfur decrease and fiber oxidation.


2003 ◽  
Vol 801 ◽  
Author(s):  
A. Bassetti ◽  
E. Bonetti ◽  
A. L. Fiorini ◽  
J. Grbovic ◽  
A. Montone ◽  
...  

ABSTRACTMagnesium carbon nanocomposites for hydrogen storage have been synthesized by ball milling with different amount of benzene, acting as a lubricant. Their microstructure has been studied by X-ray diffraction and scanning electron microscopy, while the hydrogen desorption temperature has been tested by differential scanning calorimetry. Experimental results show that the microstructure after milling, the hydrogenation capabilities of the material and the reactivity with the air are related to the amount of additives. In particular the carbon to benzene ratio seems to play a major role. In fact, with an optimum value of carbon to benzene weight ratio of 1/6, the amount of carbon being 15 wt% of the milled mixture, a decomposition heat equal to 57% of pure MgH2 was measured, even after air manipulation of the sample.


2019 ◽  
Vol 4 (4) ◽  
pp. 29-49 ◽  
Author(s):  
Andrea Pérez-Moreno ◽  
Cesar Roberto Sarabia-Castillo ◽  
Gabriela Medina-Pérez ◽  
Hermes Pérez-Hernández ◽  
Jorge Roque De La Puente ◽  
...  

Currently, some concerns regarding the potential toxicity of nanoparticles (NP) on the environment have emerged. The effect of ZnO, TiO2, and Fe2O3 NP on corn (Zea mays L.), common beans (Phaseolus vulgaris L.), nanobioremediation of polycyclic aromatic hydrocarbons (PAH), and soil organisms from agricultural or forest soils was studied at laboratory, greenhouse, and land level. The samples were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy with X-ray energy dispersion spectrometry (FESEM-EDS), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) gas chromatography (GC), ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS) and Fourier transform infrared spectrometry with attenuated total reflectance (FTIR-ATR). ZnO-NP did not harm the mycorrhizal root colonization but, the presence of ZnO-NP decreased the degradation of PAH. The synthesis of metabolites from corn was more affected by the PAH than by ZnONP. FTIR spectra showed that NP affected the synthesis of compounds from specific functional groups in common bean plants. Fe2O3-NP were attached to the body of forestsoil organisms and significantly increased the concentration of Fe in their body, while TiO2-NP changed the morphological tissue of roots and stems of common bean as witnessed by micrographs of longitudinal and cross-sections. The NP used in this research significantly changed some response variables on the experiments carried-out at laboratory, greenhouse, and land level.


2020 ◽  
Author(s):  
Denis Ilichev ◽  
Nikita Kulesh ◽  
Mikhail Mingaztdinov

We performed a technological investigation of Judith with the Head of Holofernes (a copy of Cristofano Allori’s work) from the Nizhny Tagil Museum of Fine Arts to clarify the painting’s attribution. According to the current attribution, the copy was created in the 17th century Italy. Pigment analysis using X-ray fluorescence spectroscopy and scanning electron microscopy with energy dispersive spectroscopy was undertaken in order to provide indicators of the approximate date of the Nizhny Tagil copy. The analysis results – supplemented with evidence from UV-imaging and micro-imaging, radiographic examination and studies of the paintings’ support, ground and paint layers – agree with the existing attribution but do not necessarily confirm it. Comparison of the technical characteristics of the Nizhny Tagil Judith with the techniques of Western and Russian painting allows us to extend the dating. In addition, certain fragments of the painting were examined to provide insight into specifics of differences between the copy and the original, which turned out to be mainly the results of previous restorations. Keywords: 17th century Italian painting, painting technique, canvas, pigments, ground, X-ray fluorescence, scanning electron microscopy, x-radiograph, cross-sections


2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Muriel Geldof ◽  
Inez Dorothé van der Werf ◽  
Ralph Haswell

AbstractIn this paper we present the results of quantitative measurements on the pigment chrome yellow (PbCr1−xSxO4 with 0 ≤ x ≤ 0.8) using scanning electron microscopy-wavelength dispersive X-ray analysis (SEM–WDX). Traditionally, Optical Microscopy (OM) in combination with scanning electron microscopy-energy dispersive X-ray analysis (SEM–EDX) is used for the identification of many pigments in paint cross-sections based on their particle characteristics and elemental composition. However, in the case of chrome yellow, the lead (Pb) and sulphur (S) peaks overlap, which makes quantitative analysis unreliable. SEM–WDX does not suffer from this problem and we have demonstrated that this technique can distinguish different types of chrome yellow based on the quantification of the sulphur-content of the pigment. This identification can be performed on paint cross-sections, allowing for distinction between chrome yellows in different paint layers. In addition, our study showed that the different types of chrome yellow can still be identified even in low concentrations. Van Gogh made wide use of different hues of chrome yellow. Using this method, we have identified the types of chrome yellow he used in Field with Irises near Arles, which we have been able to correlate with the information in his letters. Raman spectroscopy of the same samples confirmed the SEM–WDX results, but evidenced a higher sensitivity of the latter technique in revealing small amounts of sulphur-rich PbCr1−xSxO4 in mixtures with PbCrO4. SEM–WDX is also more accurate, because it allows the lead(II) sulphate fraction to be determined within 1 mol% absolute, whereas with Raman spectroscopy only relatively broad ranges can be defined. The on-going research of Van Gogh’s paintings as part of a cataloguing project—a collaboration between the Van Gogh Museum, the Cultural Heritage Agency of the Netherlands and Shell—opens the way for a comprehensive comparison of the chrome yellows used by Van Gogh using SEM–WDX.


2014 ◽  
Vol 804 ◽  
pp. 139-142
Author(s):  
Kyung Nam Kim ◽  
Sung Jin Kim

In this study, the characteristics of porcelain body, glaze and inlay were analyzed, using Koryo celadon shard of 10th-14thcentury. The characterization of celadon shard were investigated by Scanning electron microscopy, X-ray fluriscence, X-ray diffractometer, and Dilatometer. The characteristics of celadon shard is similar in color to gray-green with the naked eye, and the thickness of glaze layer and body is about 149.5-200μm and 4.2-8.8mm. The chemical compositions of body is SiO270.9-74.8wt%, Al2O319.4-20.5wt%, RO▪RO2(R=Ca, Mg, K) 4.0-7.0wt% and Fe2O31.3-2.7wt% in weight ratio. The high contents (12.5-24.6wt%) of calcium oxide in the glaze is considered lime type. In the chemical compositions of the white and black inlay Al2O3is 33.2-37.1wt% and 19.7wt%, and Fe2O3is 1.1wt% and 5.6wt% in weight ratio, respectively. The density of black inlay is higher than that of white inlay, and firing temperature for celadon may be about 1250°C.


Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.


Author(s):  
M. L. Zimny ◽  
A. C. Haller

During hibernation the ground squirrel is immobile, body temperature reduced and metabolism depressed. Hibernation has been shown to affect dental tissues varying degrees, although not much work has been done in this area. In limited studies, it has been shown that hibernation results in (1) mobilization of bone minerals; (2) deficient dentinogenesis and degeneration of alveolar bone; (3) presence of calculus and tears in the cementum; and (4) aggrevation of caries and pulpal and apical tooth abscesses. The purpose of this investigation was to study the effects of hibernation on dental tissues employing scanning electron microscopy (SEM) and related x-ray analyses.


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