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1.
Westlake P Siozos P Philippidis A Apostolaki C Derham B Terlixi A Perdikatsis V Jones R Anglos D 《Analytical and bioanalytical chemistry》2012,402(4):1413-1432
Wall paintings spanning two millennia of Cretan painting history and technology were analysed in an effort to determine similarities
and evolutions of painting materials and technology. A multi-technique approach was employed that combined the use of (a)
laser-induced breakdown spectroscopy (LIBS) and Raman microspectroscopy, based on mobile instrumentation, appropriate for
rapid, routine-level object characterization, and (b) non-destructive X-ray diffractometry (XRD), performed directly on the
wall painting fragment, which provides detailed information on the minerals constituting the paint. Elemental analysis data
obtained through LIBS were compared with molecular and crystal structure information from Raman spectroscopy and XRD. Cross-sections
from selected samples were also investigated by means of optical microscopy and scanning electron microscopy coupled to micro-probe
analysis and X-ray mapping that enabled identification of several mineral components of the paint confirming the results of
the XRD analysis. In parallel, replica wall paintings, created with known pigments and binding media for reference purposes,
were examined with optical microscopy and stain tested for organic materials. The overall study shows that the LIBS and Raman
techniques offer key advantages, such as instrument mobility and speed of data collection and interpretation that are particularly
important when dealing with on-site investigations. Thus, they are capable of providing important compositional information
in an effective manner that enables quick surveying of wall paintings and permit targeted sample selection for further analysis
by advanced laboratory techniques. 相似文献
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3.
Irina Fierascu Sorin Marius Avramescu Radu Claudiu Fierascu Alina Ortan Gabriel Vasilievici Carmen Cimpeanu Lia-Mara Ditu 《Journal of Thermal Analysis and Calorimetry》2017,129(3):1377-1387
Books represent a very important part of the cultural heritage, due to their double characteristics: first, as a man-made material and secondly, due to the information they store. The characterization of book paper represents a very important step in developing solutions for better conservation procedures, as well as for fully understanding their provenance. The present paper describes the analytical and microbiological evaluation of a collection of books from the nineteenth century, belonging to the authors’ private collections. The samples consisted of four books printed in Romania and five printed in France. The analytical characterization was performed using optical microscopy, thermal analysis, spectroscopic methods (X-ray fluorescence, X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, Fourier transform infrared spectroscopy), as well as by the evaluation of the degree of polymerization and the color change. The analyses were chosen in order to be either non-destructive or, at least, micro-destructive. The fungal loading determination was performed by plating the samples on the potato dextrose agar and Sabouraud with chloramphenicol agar media, for 28 days, followed by macroscopically and microscopically identification of mold species. The present study offers a complex methodology regarding the use of non- or micro-invasive techniques for evaluating the composition, state of degradation and potential risks related to microorganism colonization of paper artifacts. 相似文献
4.
《Spectrochimica Acta Part B: Atomic Spectroscopy》2006,61(10-11):1224-1228
The analyses of pigments originating from well dated ancient boat models found in Egyptian graves were used for characterization and for dating tasks of unknown objects. A nearly destruction free sampling technique using cotton buds was applied for sampling these valuable artifacts for a subsequent Total Reflection X-Ray Fluorescence Spectrometry (TXRF) analysis. Two relevant collections of Egyptian object of art were at our disposal, one of the Ägyptisches Museum Berlin and the second of the British Museum London. Three groups of colors were studied, they originate from white, red and blue/green paints, respectively. The results of the analyses performed on micro-amounts of paints (< 1 μg) show that some artifacts were misclassified and belong to other epochs. Some others were retouched with modern colors. In general, it can be stated that results obtained by Total Reflection X-Ray Fluorescence Spectrometry may dissipate some uncertainties when applying classical archaeological dating methods. 相似文献
5.
J. W. Plaue G. L. Klunder I. D. Hutcheon K. R. Czerwinski 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):551-555
Near-infrared (NIR) reflectance spectroscopy was examined as a potential tool for the determination of forensic signatures indicative of the chemical process history of uranium oxides. The ability to determine the process history of nuclear materials is a desired, but underdeveloped, area of technical nuclear forensics. Application of the NIR technique potentially offers a quick and non-destructive tool to serve this need; however, few data have been published on the compounds of interest. The viability of NIR was investigated through the analysis of a combination of laboratory-derived and real-world uranium precipitates and oxides. A set of reference uranium materials was synthesized in the laboratory using the commonly encountered aqueous precipitation reactions for uranium ore concentration and chemical separation processes (ammonia, hydrogen peroxide, sodium hydroxide, ammonium carbonate, and magnesia). NIR spectra were taken on a range of samples heat treated in air between 85 and 750 °C. X-ray diffraction patterns were also obtained to complement the NIR analysis with crystal phase information. Similar analyses were performed using a set of real-world samples, with process information obtained from the literature, to provide a comparison between materials synthesized in the laboratory and samples representative of industrial processes. 相似文献
6.
Near edge x-ray absorption fine structure (NEXAFS) spectroscopy has evolved into a powerful characterization tool for polymeric materials and is increasingly being used to elucidate composition and orientation in thin films of relevance to organic electronic devices. For accurate quantitative compositional analysis, insight into the electronic structure and the ability to assess molecular orientation, reliable reference spectra with known energy resolution and calibrated energy scale are required. We report a set of such NEXAFS spectra from 23 semiconducting polymers and some related materials that are frequently used in organic device research. 相似文献
7.
Bardelli F Barone G Crupi V Longo F Majolino D Mazzoleni P Venuti V 《Analytical and bioanalytical chemistry》2011,399(9):3147-3153
We report on a non-destructive study of Sicilian ceramic fragments of cultural heritage interest, classified as “proto-majolica”
pottery and dating back to the twelfth to thirteen centuries AD. The analytical approach used is based on the employment of
two totally non-invasive spectroscopic techniques: X-ray fluorescence (XRF), using a portable energy-dispersive XRF analyser,
and X-ray absorption spectroscopy, using synchrotron radiation as a probe (SR-XAS). XRF measurements allowed us to collect
elemental and spatially resolved information on major and minor constituents of the decorated coating of archaeological pottery
fragments, so providing preliminary results on the main components characterizing the surface. In particular, we assigned
to Fe and Mn the role of key elements of the colouring agent. With the aim of obtaining more detailed information, we performed
SR-XAS measurements at the Fe and Mn K-edges at the Italian BM08 beamline at the European Synchrotron Radiation Facility (Grenoble,
France). The experimental data were analysed by applying principal component analysis and least-squares fitting to the near-edge
part of the spectra (X-ray absorption near-edge structure) to determine the samples’ speciation. From the overall results,
umber, a class of brownish pigments characterized by a mixture of hydrated iron and manganese oxides, has been ascribed as
a pigmenting agent. 相似文献
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9.
F. Grazzi L. Bartoli F. Civita M. Zoppi 《Analytical and bioanalytical chemistry》2009,395(7):1961-1968
Neutron time-of-flight diffraction technique has been used to characterize some Japanese historical artifacts. With this method,
metal samples can be analyzed in their bulk properties without need of sampling. Results shown here were obtained at the Italian
Neutron Experimental Station (INES@ISIS) located at the pulsed neutron source ISIS (UK). The parallel use of a scanning electron
microscope equipped with an energy-dispersive X-ray fluorescence device (SEM-EDX) permitted a full quantitative characterization
of the investigated samples, namely four hand-guards (Tsubas) of Japanese swords attributed to the Tokugawa age. In particular,
we were able to obtain, in a totally non-invasive non-destructive way, a full quantitative phase characterization of the samples,
a detailed Bragg peak broadening analysis, and a quantitative texture determination. These results, complemented with those
obtained via the traditional analysis method of SEM-EDX, allowed a full characterization of both the bulk and the surface
of the artifacts. 相似文献
10.
《Spectrochimica Acta Part B: Atomic Spectroscopy》1986,41(8):837-845
A new whole rock phosphorite has been prepared in the Nuclear Materials Corp. Egypt. This is a part of the Egyptian N. M. C. program to prepare a series of rock standards. This program began in 1983 to fulfil the continuous demand for such standards in all the research laboratories.Statistical analysis for silica, phosphorus, calcium, iron and strontium in selected fractions of this rock showed the homogeneity of the sample.Conventional methods, as well as rapid analysis, inductively coupled plasma spectrometry. X-ray fluorescence, activation analysis, i.r. spectroscopy, atomic absorption and laser induced fluorescence techniques have been used to give a complete chemical characterization of the sample. 相似文献
11.
The fundamentals of chemical derivatization techniques as applied to the quantitative analysis of ultrathin surface layers
of various organic compounds via functional groups were considered. Using X-ray photoelectron spectroscopy as an example of
the most informative and almost nondestructive technique for characterization of thin layers, the general requirements imposed
on the selective chemical reactions and possible artifacts were discussed. The validity of the technique was illustrated by
the examples of analyses of surface layers of organic polymers with known concentrations of surface functional groups, plasma-modified
polymers, and carbon fibers. It was noted that selective chemical reactions are successfully used in other techniques for
studying material surfaces. The surface analysis of organic materials via functional groups can be performed with a simultaneous
increase in the sensitivity of the corresponding spectral technique. 相似文献
12.
Sven Strübbe Dr. Michal Nowakowski Dr. Roland Schoch Prof. Dr. Matthias Bauer 《Chemphyschem》2023,24(23):e202300113
A new approach for the characterization of CO2 methanation catalysts prepared by thermal decomposition of a nickel MOF by hard X-ray photon-in/photon-out spectroscopy in form of high energy resolution fluorescence detected X-ray absorption near edge structure spectroscopy (HERFD-XANES) and valence-to-core X-ray emission (VtC-XES) is presented. In contrast to conventional X-ray absorption spectroscopy, the increased resolution of both methods allows a more precise phase determination of the final catalyst, which is influenced by the conditions during MOF decomposition. 相似文献
13.
Sarmiento A Pérez-Alonso M Olivares M Castro K Martínez-Arkarazo I Fernández LA Madariaga JM 《Analytical and bioanalytical chemistry》2011,399(10):3601-3611
Fourier transform infrared spectroscopy is a powerful analytical technique to study organic materials. However, in Cultural
Heritage, since the sample under analysis is always a complicated matrix of several materials, data analysis performed through
peak-by-peak comparisons of sample spectra with those of standard compounds is a tedious method that does not always provide
good results. To overcome this problem, a chemometric model based on principal component analysis was developed to classify
and identify organic binding media in artworks. The model allows the differentiation of five families of binders: drying oils,
waxes, proteins, gums, and resins, taking into account the absorption bands in two characteristic spectral windows: C–H stretching
and carbonyl band. This new methodology was applied in the characterization of binders in three kinds of artworks: papers
of historical, archeological, and artistic value, easel paintings, and polychromed stone-based sculptures. 相似文献
14.
Dou Y Zou T Liu T Qu N Ren Y 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,68(5):1201-1206
Near-infrared (NIR) spectroscopy was used in simultaneous, non-destructive analysis of antipyriine and caffeine citrate tablets. Principal component artificial neural networks (PC-ANNs) were used to construct models for the analytes, using the testing set for external validation. Four pretreated spectra, namely, first-derivative, second-derivative, standard normal variate (SNV) and multiplicative scatter correction (MSC) spectra led to simplified and more robust models than conventional spectra. In PC-ANNs models, the spectra data were analyzed by principal component analysis (PCA) firstly. Then the scores of the principal compounds (PCs) were chosen as input nodes for input layer instead of the spectra data. The artificial neural networks (ANNs) models using the spectra data as input nodes were also established, which were compared with the PC-ANNs models. The result shows the SNV model of PC-ANNs multivariate calibration has the lowest training error and predicting error. The concept of the degree of approximation was introduced and performed as the selective criterion of the optimum network parameters. 相似文献
15.
Characterization of metal threads on historical textile materials is important for preservation of valuable cultural heritage. Obtained results dictate decisions on cleaning, conservation and restoration steps. The most important part of characterization is chemical analysis of originally applied materials, since this enables understanding the nature of chemical and physical degradation and determines the cleaning methods. Methods applied should be non-destructive and sensitive enough to detect trace elements in small sample amounts. The goal of this research was to describe the most useful procedures for fast and simple determination of specific metals of interest. Therefore we propose application of scanning electron microscopy equipped with EDS detector (SEM-EDS) for sample surface analysis and inductively coupled plasma-optical emission spectroscopy (ICP-OES) for chemical analysis of metals threads. For quality insurance reasons, a comparative method applied for chemical analysis was atomic absorption spectrometry (AAS). This combination of methods has proven to be very useful in analysis of historical samples, since SEM-EDS was a simple and non-destructive method which provided information on chemical composition of sample surfaces, while ICP-OES and AAS enabled the full insight into the average chemical composition of samples. Nevertheless, both ICP-OES and AAS were destructive methods which demanded dissolving of samples prior to the analysis. In this work nine different metal fibers collected from historical textile materials were characterized. Proposed methods enabled obtaining information on sample constitution, morphology, topology and chemical composition. 相似文献
16.
Variable incidence angle X-ray absorption fine structure (VIAXAFS) spectroscopy offers a non-destructive ability to investigate film nano-structures. This technique was applied, spanning sample-beam angles from a grazing to normal incidence on a film obtained by zirconia sputtering on flat sample of stainless steel. X-ray absorption fine structure analysis on the Zr K edge identified chemical, defects and fractal structures through the film depth. VIAXAFS revealed occurrence of zirconium monoxide fractions at the surface a reduced state of zirconium oxide vs. the zirconium dioxide bulk. The discussion underlines that the technique may quantify the profile of various sub-layers, nano-pores, dislocations, vacancies or defect features. 相似文献
17.
《Progress in Surface Science》1986,22(2):101-179
Complete characterization of an adsorbate system requires that many physical and chemical properties be determined from experimental data. Important quantities include: (1) the structure of the adsorbate phases; (2) thermodynamic quantities such as heats and entropies of adsorption and desorption; and (3) kinetic parameters which describe adsorption, desorption and ordering processes in the adsorbate phase. No single experimental technique can provide all of the necessary data over the complete range of coverages and temperatures and several techniques are usually required to minimize experimental ambiguities and artifacts. This review demonstrates the utility of such a multitechnique approach by describing a complete study of the chemisorption of molecular nitrogen of the nickel (110) surface. The techniques used are low-energy electron diffraction (LEED), ion scattering spectroscopy (ISS), infrared reflection absorption spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), work function change measurements, and thermal desorption spectroscopy (TDS). The data from these experimental studies are correlated and used to test theoretical models. Extensive physical and chemical data for the N2/Ni(110) system are presented and compared with that of other molecular adsorption systems. 相似文献
18.
Brambilla L Riedo C Baraldi C Nevin A Gamberini MC D'Andrea C Chiantore O Goidanich S Toniolo L 《Analytical and bioanalytical chemistry》2011,401(6):1827-1837
Natural organic materials used to prepare pharmaceutical mixtures including ointments and balsams have been characterized
by a combined non-destructive spectroscopic analytical approach. Three classes of materials which include vegetable oils (olive,
almond and palm tree), gums (Arabic and Tragacanth) and beeswax are considered in this study according to their widespread
use reported in ancient recipes. Micro-FTIR, micro-Raman and fluorescence spectroscopies have been applied to fresh and mildly
thermally aged samples. Vibrational characterization of these organic compounds is reported together with tabulated frequencies,
highlighting all spectral features and changes in spectra which occur following artificial aging. Synchronous fluorescence
spectroscopy has been shown to be particularly useful for the assessment of changes in oils after aging; spectral difference
between Tragacanth and Arabic gum could be due to variations in origin and processing of raw materials. Analysis of these
materials using non-destructive spectroscopic techniques provided important analytical information which could be used to
guide further study. 相似文献
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20.
采用传统高温固相法合成了系列Fe掺杂钐镓石榴石Sm3Ga5-xFexO12(x=1,2,3,4)可逆热致变色材料, 并通过粉末X射线衍射(XRD)、 红外光谱(FTIR)、 拉曼光谱(Raman)、 扫描电子显微镜(SEM)、 X射线光电子能谱(XPS)及固体紫外光谱分析技术研究了物质的结构及性质. 在室温下, 随着铁掺杂量的增加, 样品的颜色从亮黄绿色逐渐变为深墨绿色, 且随着温度从室温升至500 ℃, 样品的颜色也逐渐变为相应的橘黄色和棕色. 样品在室温下所呈现的黄绿色是源于其在紫色光区域及橙红色光区域内有相应的吸收行为, 且随着温度的升高, 吸收行为持续红移, 样品颜色也随之发生变化. 相似文献