Applications of Laboratory-Based X-Ray Microfluorescence Analysis in Archaeometry

1998 ◽  
Vol 4 (S2) ◽  
pp. 368-369
Author(s):  
N.E. Pingitore ◽  
J.D. Leach ◽  
A. Iglesias ◽  
C.G. Sampson ◽  
D.L. Carmichael ◽  
...  
Keyword(s):  
Energy Dispersive Spectrometer ◽  
Optical Microscope ◽  
Beam Diameter ◽  
X Ray ◽  
Spatially Resolved ◽  
Price Range ◽  
Archaeological Materials ◽  
Potential Impact ◽  
Academic Laboratory ◽  
Non Destructive

X-ray microfluorescence (XRMF) is spatially resolved x-ray fluorescence (XRF) analysis of elemental composition. Formerly available only at synchrotron sources, recent development of commercial instruments has brought a tamer version of this technique into the size and price range of the academic laboratory. Our Kevex Omicron system features a primary beam diameter as small as 30 μm, with an energy dispersive spectrometer collecting the x-ray spectrum from Na to U. The micro-positioning stage and optical microscope permit selective spatially resolved analysis on the surfaces of objects as large as a desktop dictionary. The large sample stage, functional spatial resolution, and non-destructive analysis present significant opportunities for elemental analysis of a variety of archaeological materials. In particular, objects which for aesthetic, religious, regulatory, or economic reasons cannot be subjected to any alteration in sample preparation may still be analyzed by XRMF. Our laboratory has been conducting a number of investigations which illustrate the potential impact of XRMF technology on archaeometry.

scholarly journals Determining Chemically and Spatially Resolved Atomic Profile of Low Contrast Interface Structure with High Resolution

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Maheswar Nayak ◽  
P. C. Pradhan ◽  
G. S. Lodha ◽  
A. Sokolov ◽  
F. Schäfers
Keyword(s):  
High Resolution ◽  
Electron Density ◽  
Resonant Scattering ◽  
Interface Structure ◽  
Distribution Profile ◽  
Low Contrast ◽  
X Ray ◽  
Spatially Resolved ◽  
Quantitative Manner ◽  
Non Destructive

Abstract We present precise measurements of atomic distributions of low electron density contrast at a buried interface using soft x-ray resonant scattering. This approach allows one to construct chemically and spatially highly resolved atomic distribution profile upto several tens of nanometer in a non-destructive and quantitative manner. We demonstrate that the method is sensitive enough to resolve compositional differences of few atomic percent in nano-scaled layered structures of elements with poor electron density differences (0.05%). The present study near the edge of potential impurities in soft x-ray range for low-Z system will stimulate the activity in that field.

Analysis on Internal Defect of 319S Aluminum Alloy Impeller by Semi-Solid Thioxcasting

2016 ◽  
Vol 850 ◽  
pp. 219-225
Author(s):  
Yan Hong Jing ◽  
Hong Xing Lu ◽  
Da Quan Li ◽  
Qiang Zhu
Keyword(s):  
Aluminum Alloy ◽  
Energy Dispersive Spectrometer ◽  
Casting Process ◽  
Optical Microscope ◽  
Machined Surface ◽  
X Ray ◽  
Single Defect ◽  
Die Casting Process ◽  
Semi Solid ◽  
Eutectic Zone

In the present investigation a batch of impellers made of 319S aluminum alloy with about 300 pieces and produced by semi-solid thixocasting process were subjected the ultrasonic testing (UT). The experimental results revealed that the equivalent size of the defects in the impellers was not more than φ0.4mm FBH+12dB. And there were two main types of defects in 12 mm depth area from the machined surface, where defect was apt to form. One type was single defect and the other was intensive defect. Moreover, other nondestructive testing (NDT) was used to test some impellers containing typical defect, and the result suggests that UT was more sensitive than x-ray testing. The defects existed in the impellers were investigated by Optical Microscope (OM) and Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectrometer (EDS). The observation showed that the both types of defects existed in eutectic zone. The single defect derived from billet and the intensive defect came from die casting process.

scholarly journals Multi-Analytical Research on the Caisson Painting of Dayu Temple in Hancheng, Shaanxi, China

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1372
Author(s):  
Jiaxin Li ◽  
Bingjie Mai ◽  
Peng Fu ◽  
Gele Teri ◽  
Yanli Li ◽  
...  
Keyword(s):  
Energy Dispersive Spectrometer ◽  
Optical Microscope ◽  
Scientific Data ◽  
Depth Of Field ◽  
Confocal Laser ◽  
Animal Glue ◽  
Analytical Methodology ◽  
X Ray ◽  
Laser Raman ◽  
Corroborative Evidence

In this research, the caisson painting of Dayu Temple in Hancheng, Shaanxi, China, was analyzed via a multi-analytical methodology, using a pH meter, an ultra-depth-of-field optical microscope, a scanning electron microscope–energy dispersive spectrometer (SEM-EDS), a high-resolution X-ray diffractometer (XRD), a micro-confocal laser Raman spectrometer, a gas chromatography mass spectrometer (GC-MS), and X-ray fluorescence spectroscopy (XRF). With the corroborative evidence derived from the above analyses, it could be determined that the caisson painting of Dayu Temple was painted on bamboo paper and attached to hemlock wood substrate of the Pinaceae Tsuga genus using starch paste, with common colorants such as carbon black, cinnabar mixed with a small amount of red lead, ultramarine, and ultramarine mixed with Paris green, with animal glue having been adopted as a sizing agent. These results provide important scientific data for the production craft of precious caisson paintings, contributing to the revelation of their historic, artistic, and scientific value, and should enable conservators to make informed decisions in restoration.

Study on Atmospheric Corrosion Behaviour of Sicp/Al Composite

2010 ◽  
Vol 136 ◽  
pp. 275-278
Author(s):  
Xian Liang Zhou ◽  
Duo Sheng Li ◽  
Ai Hua Zou ◽  
Xiao Zhen Hua ◽  
G.Z. Ye ◽  
...  
Keyword(s):  
Atmospheric Corrosion ◽  
Corrosion Behaviour ◽  
Energy Dispersive Spectrometer ◽  
Optical Microscope ◽  
Atmospheric Environment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Composite ◽  
Amorphous Al2o3 ◽  
Scanning Electron

SiCp/Al composite was fabricated by the method of pressureless-infiltration. In atmospheric environment, the atmospheric corrosion behavior of SiCp/Al composites (ZL101+49%SiC+5%Mg) was studied by mass loss, optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and Fourier transform infrared spectroscopy (FTIR), respectivelhy.The results show that the corrosion rate of the SiCp/Al composites increases with increasing of time in atmospheric environment. Pitting corrosion is the main characteristic of SiCp/Al composite, and corrosion area gradually extends around with time increasing. At last, sheet like corrosion substrates distribute in the surface of n the SiCp/Al composites. Amorphous Al2O3 and amorphous AlxSO4yOHz are the main corrosion products.

scholarly journals Effect of Micro-Scale Er on the Microstructure and Fluidity of ZL205A Alloy

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1688 ◽  
Author(s):  
Tingbiao Guo ◽  
Bing Wang ◽  
Zhanfei Zhang ◽  
Quanzhen Sun ◽  
Yuhua Jin ◽  
...  
Keyword(s):  
Energy Dispersive Spectrometer ◽  
Fracture Morphology ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
Fracture Characteristics ◽  
X Ray ◽  
Micro Scale ◽  
Heat Treated ◽  
Zl205a Alloy ◽  
Increasing Precipitation

The effect of Er addition on the fluidity and microstructure transformation of the as-cast and T5 heat-treated ZL205A alloys was investigated by optical microscope (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The fluidity of the liquid metal after adding Er was tested and the fracture characteristics of the material were analyzed. The results indicated that Er was mainly dissolved into an α–Al matrix near the grain boundaries (GBs). It is easily segregated and enriched in the intersection of the GBs or the interface between the α and θ phase, which caused the intermetallic compounds to be distributed along the GBs to the neck and to fuse. Er could also inhibit the diffusion of Cu atoms in the process of solid solution, so that increased the residual eutectic structures in the crystal, while accelerating the precipitation progress of the Guinier–Preston (GP) zone and θ’ phase and increasing precipitation of the θ phase. A small amount of precipitation of θ phase and micro-scale Er (0.1–0.5 wt %) can significantly increase the fluidity and reduce the casting defects, which can effectively improve the castability of the ZL205A alloy. The interface between the (Al8Cu4Er) phase and matrix is the main area of microcracks, through analyzing the fracture morphology.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Energy Dispersive X-Ray Measurements of thin Metal Foils

1976 ◽  
Vol 34 ◽  
pp. 426-427
Author(s):  
J. Bentley ◽  
E. A. Kenik
Keyword(s):  
Materials Science ◽  
Energy Dispersive Spectrometer ◽  
Thin Foil ◽  
Thin Metal ◽  
Energy Dispersive ◽  
Thin Specimen ◽  
X Ray ◽  
Metal Foils ◽  
Small Probe ◽  
Scanning Transmission

Instruments combining a 100 kV transmission electron microscope (TEM) with scanning transmission (STEM), secondary electron (SEM) and x-ray energy dispersive spectrometer (EDS) attachments to give analytical capabilities are becoming increasingly available and useful. Some typical applications in the field of materials science which make use of the small probe size and thin specimen geometry are the chemical analysis of small precipitates contained within a thin foil and the measurement of chemical concentration profiles near microstructural features such as grain boundaries, point defect clusters, dislocations, or precipitates. Quantitative x-ray analysis of bulk samples using EDS on a conventional SEM is reasonably well established, but much less work has been performed on thin metal foils using the higher accelerating voltages available in TEM based instruments.

High spatial resolution x-ray microanalysis of interfaces

1995 ◽  
Vol 53 ◽  
pp. 284-285
Author(s):  
J. R. Michael
Keyword(s):  
Spatial Resolution ◽  
Electron Probe ◽  
Solid Angle ◽  
Collection Efficiency ◽  
Spatial Scales ◽  
Energy Dispersive Spectrometer ◽  
X Rays ◽  
X Ray ◽  
Probe Size ◽  
Brightness Field

X-ray microanalysis in the analytical electron microscope (AEM) refers to a technique by which chemical composition can be determined on spatial scales of less than 10 nm. There are many factors that influence the quality of x-ray microanalysis. The minimum probe size with sufficient current for microanalysis that can be generated determines the ultimate spatial resolution of each individual microanalysis. However, it is also necessary to collect efficiently the x-rays generated. Modern high brightness field emission gun equipped AEMs can now generate probes that are less than 1 nm in diameter with high probe currents. Improving the x-ray collection solid angle of the solid state energy dispersive spectrometer (EDS) results in more efficient collection of x-ray generated by the interaction of the electron probe with the specimen, thus reducing the minimum detectability limit. The combination of decreased interaction volume due to smaller electron probe size and the increased collection efficiency due to larger solid angle of x-ray collection should enhance our ability to study interfacial segregation.

Layered and ion implantation specimens as possible reference materials for the electron-probe microanalysis

1992 ◽  
Vol 50 (2) ◽  
pp. 1652-1653
Author(s):  
G. Remond ◽  
R.H. Packwood ◽  
C. Gilles ◽  
S. Chryssoulis
Keyword(s):  
Ion Implantation ◽  
Reference Materials ◽  
Analytical Techniques ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
X Ray ◽  
Spatially Resolved ◽  
Analytical Expressions ◽  
Original Approach ◽  
Depth Concentration

Merits and limitations of layered and ion implanted specimens as possible reference materials to calibrate spatially resolved analytical techniques are discussed and illustrated for the case of gold analysis in minerals by means of x-ray spectrometry with the EPMA. To overcome the random heterogeneities of minerals, thin film deposition and ion implantation may offer an original approach to the manufacture of controlled concentration/ distribution reference materials for quantification of trace elements with the same matrix as the unknown.In order to evaluate the accuracy of data obtained by EPMA we have compared measured and calculated x-ray intensities for homogeneous and heterogeneous specimens. Au Lα and Au Mα x-ray intensities were recorded at various electron beam energies, and hence at various sampling depths, for gold coated and gold implanted specimens. X-ray intensity calculations are based on the use of analytical expressions for both the depth ionization Φ (ρz) and the depth concentration C (ρz) distributions respectively.

Highlights in the history of X-ray topography1

1995 ◽  
Vol 210 (6) ◽  
Author(s):  
A. R. Lang
Keyword(s):  
Magnetic Domain ◽  
Diffraction Theory ◽  
Dislocation Loops ◽  
X Ray Diffraction ◽  
X Ray ◽  
Domain Structures ◽  
Structure Factors ◽  
History Of ◽  
Dislocation Sources ◽  
Non Destructive

AbstractX-ray topography provides a non-destructive method of mapping point-by-point variations in orientation and reflecting power within crystals. The discovery, made by several workers independently, that in nearly perfect crystals it was possible to detect individual dislocations by X-ray diffraction contrast started an epoch of rapid exploitation of X-ray topography as a new, general method for assessing crystal perfection. Another discovery, that of X-ray Pendellösung, led to important theoretical developments in X-ray diffraction theory and to a new and precise method for measuring structure factors on an absolute scale. Other highlights picked out for mention are studies of Frank-Read dislocation sources, the discovery of long dislocation helices and lines of coaxial dislocation loops in aluminium, of internal magnetic domain structures in Fe-3 wt.% Si, and of stacking faults in silicon and natural diamonds.

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